This review summarizes a selection of epidemiologic research assessing the associations between carbohydrate intake and cancer incidence and survival. Evidence for plausible biological mechanisms is also considered.The mechanistic paradigm explaining the relationship between carbohydrates and cancer risk has been contested by numerous observational studies.Carbohydrates have conventionally been ascribed a deleterious role in the field of cancer research due to previous preclinical findings. A breadth of studies suggests that complex carbohydrate intake is inversely associated with risk of a number of cancer types. Data from studies assessing simple carbohydrates and cancer risk are mixed. Furthermore, recommendations for subsequent studies are framed. An estimated 606,880 deaths in the USA will be attributable to cancer in 2019 ••. Diet Carbohydrate intake is one aspect of diet that has been hypothesized to modulate cancer risk depending on the amount and type consumed. Carbohydrates are a broad category of biomolecules, which, in their monosaccharide forms, function as preferred cellular energy substrates . Aside fEarly findings from experimental in vitro and in vivo models enhanced understanding of the acute physiological effects of carbohydrates. On the basis of these discoveries, a series of etiological frameworks tying their consumption to cancer risk were hypothesized. Owing to the work of Otto Warburg, a deleterious role, albeit a simplistic one, was ascribed to dietary carbohydrates; a hypothesis that, as we shall examine, has seemingly been only moderately supported by observational data. A more coherent framework, primarily implicating insulin-signaling networks, was born out of subsequent research. These hypotheses, detailed below, have provided a foundation that has motivated a vast collection of the observational studies we address in this review.Exploitation of glycolytic pathways and their corresponding machinery are appreciable metabolic adaptations that cancer cells use to enhance and perpetuate their survival and proliferative capabilities. Specifically, tumor cells transition from aerobic cellular respiration to aerobic glycolysis as the primary energy-harvesting mechanism . This hiThe insulin/IGF-1 signaling axis plays a critical role in glucose metabolism and subsequently modifies cellular proliferation and growth . InsulinMany anabolic functions of the IGF-1 axis, such as the activation of PI3K/Akt, parallel those of the insulin-IR signaling cascade , 20. DysConsumption of simple sugars, glycemic index (GI) and glycemic load (GL), has been hypothesized to increase cancer risk, although findings have been mixed. Makarem et al. analysis of the Framingham cohort reported no significant associations between GI or total carbohydrates and risk of several adiposity-related cancers . NonetheAn ecological analysis undertaken by Grasburger and his colleagues on observational data collected across 39 European countries reported weak and moderate positive associations between refined sugar consumption and CRC incidence in men and women, respectively . GiovannUsing GL as a predictor, Zelenskiy et al. case-control study reported significantly increased odds of CRC in the second through fourth upper quartiles of GL consumption . The effArguably, the most comprehensive set of meta-analyses conducted to date, by Reynolds et al., included 185 studies that examined several carbohydrate predictors  and their associations with a range of clinical outcomes, including incidence of many adiposity-related cancers  and total cancer mortality. Both randomized controlled trials (RCTs) and prospective cohort studies were considered. Results from the meta-analysis on GI and CRC incidence, which included 10 studies, reported a non-significant but 5% increased risk associated with greater consumption of higher GI foods . The onlStudies examining the relationship between high consumption of simple carbohydrate and the risk of PCa have been inconsistent. While some studies suggested a positive association between simple carbohydrate consumption and risk of PCa, others reported null associations. The two longitudinal studies cited by Makarem et al. in their systematic review come from Giovannucci et al. and Drake et al. who reported on the Health Professionals Follow-Up and Malmö Diet and Cancer cohorts, respectively. Notably, Giovannucci et al. found a significantly reduced risk of advanced PCa associated with higher fructose consumption . In contThe data on the risk of female reproductive cancers in relation to simple carbohydrate intake, primarily GL and GI, have been inconsistent. The ecological associations reported by Grasburger et al. indicated moderate positive linear relationships between the consumption of refined sugar and breast cancer . An earlMullie et al. were the first to conduct a meta-analysis that adjusted for ER status. However, they found that ER status did not change relative risk estimates and reported modest increases in risk between the highest versus lowest levels of GI and GL regardless of ER status . In contMakarem et al. 2018 systematic review identified 11 prospective cohort studies that examined the following carbohydrate variables in relation to risk of breast, endometrial, and ovarian cancers: total sugar, added sugar, fructose, sucrose, sugary foods, and sugar-sweetened beverages ••. The sCiting evidence of disparate CRC incidence among rural African and Western populations, Denis Burkitt postulated fiber intake as responsible for these observations given the ubiquitous and significantly higher consumptions exhibited by the former group . Since tInitial epidemiologic research examining fiber and primary prevention of CRC risk was mixed. A meta-analysis of 13 prospective cohort studies by Park et al. was unable to ascertain a significant inverse relationship between fiber intake and CRC risk . An analEvidence of a protective association with high fiber intake emerged from an analysis by Murphy et al. of EPIC data. Specifically, every 10-g increase in total fiber consumption was associated with a 13% reduction of risk . In a mePCa progression and risk have been previously correlated to the IGF-1 system. Its associations with increased concentrations of IGFBP and IGF-1 were demonstrated through several case-control studies –66. A stMore recent meta-analyses on epidemiologic data suggested a null association between fiber intake and PCa risk. Sheng et al. meta-analysis of 17 observational studies reported a significant protective association between fiber and PCa risk when considering only case-control studies . When exA pooled analysis of seven individual case-control studies participating in the International Head and Neck Cancer Epidemiology Consortium (INHANCE) characterized dietary patterns and assessed their associations with oropharyngeal and laryngeal cancers. Results of their analysis revealed that an “antioxidants and fiber” pattern was associated with a significant inverse association with these cancer types . In a siThe most comprehensive longitudinal cohort study of complex carbohydrates and head and neck cancer risk to date comes from Lam et al., whose analysis on the NIH-AARP Diet and Health Study cohort revealed a significant inverse association between fiber and whole grains with head and neck cancer risk over the 11-year follow-up period . Resultsn = 20) and included both pre- and post-menopausal cohorts.The systematic review and meta-analysis by Chen et al. included 24 individual observational studies and reported a significant inverse association between fiber intake and breast cancer risk •. NotablThe scope of evidence linking carbohydrate intake to cancer recurrence and survival is limited. However, a selection of studies addressing survival outcomes is summarized below.An analysis of the EPIC cohort that assessed pre-diagnosis associations between dietary fiber and survival of non-metastatic CRC cases reported null results . HoweverSong et al. demonstrated dose-response patterns and significant reductions in mortality risk with high fiber intake in CRC survivors pooled from the Nurses’ Health Study and the Health Professionals Follow-up Study cohorts. Fully adjusted post-diagnosis models suggested a 22% and 14% reduced risk of CRC-specific and all-cause mortality, respectively, for each 5-g increase in dietary fiber ••. With A prospective cohort study of head and neck cancer patients by Arthur et al. examined associations between pre- and post-treatment carbohydrate intake and recurrence, disease-specific, and all-cause mortality. Results indicated that high pre-treatment intake of total carbohydrate, total sugar, glycemic load, and simple carbohydrate foods  were significantly associated with increased risk of all-cause mortality ••. TotalA nested case-control study conducted by Emond et al. investigated the association between carbohydrate intake and breast cancer recurrence . Cases wA longitudinal study in ovarian cancer survivors suggested an inverse association between complex carbohydrate consumption and mortality . PlaydonThe majority of the research on carbohydrates and cancer risk reviewed herein was derived largely from case-control and cohort designs, which makes it impossible to draw definitive conclusions of causality. Moreover, the breadth and strength of the evidence were most convincing for associations between fiber and complex carbohydrate consumption with CRC risk, although a similar association is suggested in other cancer types. Consistent with the findings of this review, the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) now recognizes dietary fiber as a probable protective agent against colorectal carcinogenesis ••. The dThere is an urgent need for additional prospective cohort studies and RCTs, particularly for cancer types other than CRC and of tertiary cancer prevention. There was significant heterogeneity across the studies reviewed and thus adopting consistent methodologies for studying the associations between carbohydrate intake and cancer risk are needed. Doing so will lead to more consistent results that can be used to design rigorous RCTs that will ultimately inform public health and clinical recommendations. Specifically, consistent examination of various subtypes of carbohydrates should be considered in future research. Many studies considered carbohydrates as either an all-encompassing predictor or in stratified classifications , albeit at times confounded by inappropriate groupings . Moreover, it must be noted that obesity is an accepted etiologic factor implicated in several of the cancer types considered in this review ••. As suClinical recommendations based off this review need be tempered. The data do not support any conclusion regarding the feasibility or efficacy of extreme carbohydrate-restricting dietary protocols, such as the ketogenic diet, despite the fact that several experimental mouse models have highlighted its benefits when implemented concomitantly with pharmacological treatments. Several recent reviews on the topic of the ketogenic diet and cancer have been published, and thus, it was not considered in the current review , 83, 84.In sum, the body of evidence related to carbohydrates and cancer risk is strongest for the association between fiber and CRC, where increased consumption is associated with reduced risk of disease development and mortality after diagnosis. Results of studies examining complex carbohydrates and risk of cancer types other than CRC generally suggest a protective association, whereas results of studies examining simple carbohydrates and cancer risk are mixed. Future prospective studies and RCTs that include homogenous study populations and consistency in study design and methods of modeling carbohydrate intake are urgently needed. Lastly, given the rapidly growing population of adults living with a history of cancer worldwide, more research should be conducted to determine how varying amount and type of carbohydrates may impact outcomes after cancer diagnosis, including recurrence, survival, second primary cancers, and health-related quality of life .


Non-human primates (NHPs), particularly macaques, serve as critical and highly relevant pre-clinical models of human disease. The similarity in human and macaque natural disease susceptibility, along with parallel genetic risk alleles, underscores the value of macaques in the development of effective treatment strategies. Nonetheless, there are limited genomic resources available to support the exploration and discovery of macaque models of inherited disease. Notably, there are few public databases tailored to searching NHP sequence variants, and no other database making use of centralized variant calling, or providing genotype-level data and predicted pathogenic effects for each variant.The macaque Genotype And Phenotype (mGAP) resource is the first public website providing searchable, annotated macaque variant data. The mGAP resource includes a catalog of high confidence variants, derived from whole genome sequence (WGS). The current mGAP release at time of publication (1.7) contains 17,087,212 variants based on the sequence analysis of 293 rhesus macaques. A custom pipeline was developed to enable annotation of the macaque variants, leveraging human data sources that include regulatory elements , known disease- or phenotype-associated variants (GRASP), predicted impact , and sequence conservation . Currently mGAP includes 2767 variants that are identical to alleles listed in the human ClinVar database, of which 276 variants, spanning 258 genes, are identified as pathogenic. An additional 12,472 variants are predicted as high impact (SnpEff) and 13,129 are predicted as damaging (PolyPhen2). In total, these variants are predicted to be associated with more than 2000 human disease or phenotype entries reported in OMIM (Online Mendelian Inheritance in Man). Importantly, mGAP also provides genotype-level data for all subjects, allowing identification of specific individuals harboring alleles of interest.https://mgap.ohsu.edu). Together with the extensive variant annotations, mGAP presents unprecedented opportunity to investigate potential genetic associations with currently characterized disease models, and to uncover new macaque models based on parallels with human risk alleles.The mGAP resource provides variant and genotype data from hundreds of rhesus macaques, processed in a consistent manner across all subjects (The online version of this article (10.1186/s12864-019-5559-7) contains supplementary material, which is available to authorized users. One of the most exciting outcomes from the genomic era and the plunging costs of DNA sequencing is the increased efficiency to identify genetic variants associated with disease risk and progression. This leap forward portends the rapidly approaching era of predictive genetic medicine and personalized therapy. Translating insight into the clinic will require robust genomic models to test and advance gene-based therapeutic approaches. Non-human primates (NHPs), especially macaques, are well positioned to serve as a critical link, providing a highly relevant pre-clinical model. Due to their high level of genomic, physiological, anatomical, neurological and behavioral similarity to humans, macaques are often indispensable to the study of complex human disease.The close evolutionary history of macaques and humans is evident in their highly similar breadth of natural disease susceptibilities. Moreover, the parallel genetic associations already reported for a broad range of diseases Table  suggestsDespite the clear value of macaques as a human disease models, there are very limited genomic resources available to support the exploration and discovery of potential natural models of genetic disease. Notably, there is a paucity of public databases tailored to searching NHP sequence variant and phenotypic data. The major human variant databases, dbSNP  and dbVaA key feature of mGAP is a catalog of high confidence genomic variants, derived from high depth, whole genome data. The current mGAP release at the time of this publication 1.7) contains whole genome data from 293 Indian-origin rhesus macaques. These animals were selected from a multi-generational outbred cohort of macaques bred at the Oregon National Primate Research Center (average kinship 0.0016). Genomic DNA was isolated, used to generate Illumina libraries as previously described, followed by sequencing on an Illumina XTen sequencer . We obta.7 contaiThe mGAP 1.7 release contains 17,087,212 passing variants from this dataset . Of these, 276 are listed as pathogenic, spanning 258 distinct genes. This list includes variants linked to 160 distinct disorders/phenotypes, including cardiovascular phenotypes , immune disorders , and many additional rare diseases . Our annotation process also identified many variants predicted to severely impact protein coding, including 12,472 predicted as high impact by SnpEff and 13,129 predicted as damaging by PolyPhen2, encompassing 4091 genes with predicted frameshift mutations. A complete list of variants is available through the mGAP website.https://svn.mgt.labkey.host/stedi/trunk). The primary mode of data storage for each release is the annotated VCF file, which has the advantage of being easily exportable and capable of being processed with most standard variant-processing tools. Limited summary statistics on each release are stored in the database, such as the number of variants and a breakdown of variants by type. The site includes demographics data on all animals, which is also stored and implemented using the LabKey study framework [The mGAP website was developed as a module for LabKey Server , writtenramework .https://mgap.ohsu.edu/. The main page of the website contains a summary of the current release, and tabs for each of the main datatypes: the variant catalog, macaque phenotype and model information, cohort/demographics data and raw sequence data  represents a critical resource for genomic research that fills a major gap in the NHP research field. mGAP provides a unique combination of variant and genotype data from a large cohort of Indian-origin rhesus macaques, processed in a consistent manner across all subjects. While comparable datasets are common for most models, until now they have been lacking for macaques. These data serve basic yet essential functions to support modern genomic analyses, including a catalog of common and rare variants in macaques, coupled with allele frequency and genotype-level data. The mGAP website is designed to allow exploration of data, primarily though the genome browser, or complete export of the entire dataset into common formats for external analysis.The resources provided by mGAP are designed to advance genomic research in macaques, with the primary goal of identifying and developing new genetic disease models. In this regard, the resource has utility that extends beyond the initial set of sequenced animals. Investigators can explore potential associations between a macaque phenotype of interest and variants in candidate genes by using the mGAP browser to identify compelling candidate variants based on predicted translational effects, allele frequencies and cross species conservation. Prioritized variants can then be evaluated using targeted re-sequencing or genotype-specific assays in macaques lacking genome-wide sequence and tested for phenotype association.mGAP also presents new opportunities to reveal currently unrecognized macaque disease models, which is facilitated by the highlighted ‘Variants of Interest’ list on the website. This list includes variants that are either identical to those linked to disease in humans or have a predicted highly deleterious impact on protein coding. Supporting this ‘reverse genetic’ approach to model discovery, a comprehensive medical record is established for each of the rhesus macaques housed at the Oregon National Primate Research Center, including regularly updated clinical data, and as available, imaging, histology, and pathology notations. The identification of naturally occurring genetic macaque models provides several advantages over genetically-induced models, such as those produced using CRISPR-like approaches, since there is no danger of experimentally induced off-target effects, the phenotypic evaluation can be carried out in existing animals at considerably less cost than creation of transgenic animals, and the identification of multiple subjects with the desired genotype has the potential to support model expansion.The rapid expansion of ‘-omic’ level data produced by both NHP and human studies, affords exciting new opportunities for high-resolution data integration and analysis. In this regard, mGAP provides a missing link in the coordinated study of genomic variants in combination with macaque transcriptomic, metabolomic and proteomic findings –58. In pIn addition to model discovery and analysis, mGAP also provides a much-needed resource to improve the design of molecular research tools. For example, information on variant location and allele frequency is critical information to optimize the design of DNA primers for use in PCR amplification or peptide-based ligands for antibody generation. Similarly, SNP array designs for research use or colony management applications will benefit from the available information on allele frequencies and potential pathogenic effects, guiding the selection of appropriate variants to meet the goals of each tool.Interpretation of genome-wide data can be daunting. For human genomic data, tools continue to be developed to sift through variants and prioritize potentially damaging or relevant variants. The algorithms used in these tools are generally aided by the considerable body of human genome annotation, ranging from catalogs of disease-associated variants to functional annotation developed by experimental studies. Because these resources do not currently exist for macaques, we developed a process to annotate macaque variants using available human data. The annotation processes developed for mGAP can also serve as a template, adapted to enhance the interpretation of genomic variants associated with other model organisms. While lifting human annotation to macaque has value and can identify relevant variants, interpreting annotation across species must be viewed carefully and can have pitfalls, especially for non-coding and regulatory regions. It is therefore important to develop macaque-specific functional annotation, such as data linking genetic variation to changes in gene expression (i.e. eQTLs) or other functional genomic data. The rapid decrease in sequence costs, and rise of massively parallel single-cell analysis approaches, should enable these data to be generated much more rapidly and at a fraction of the cost of the analogous human studies.While the majority of mGAP data is centered on Indian-origin rhesus macaques from the ONPRC breeding colony, previous studies have found that these macaques are genetically representative of major research captive breeding populations at other US National Primate Research Centers . FurtherAdditional file 1:Table S1. Summary table of per-sample sequence data. (XLSX 27 kb)Additional file 2:Supplemental Methods. (DOCX 24 kb)Additional file 3:Figure S1. Derived allele frequency spectrum of macaque variants shared with the 1000Genomes Phase 3 dataset. The proportion of variants for each allele frequency is shown for the entire mGAP release 1.7 dataset (blue), and the subset of variants that intersect with sites reported in the 1000Genomes Phase 3 dataset (red). 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Workload and demands on hospital staff have been growing over recent years. To ensure patient and occupational safety, hospitals increasingly survey staff about perceived working conditions and safety culture. At the same time, routine data are used to manage resources and performance. This study aims to understand the relation between survey-derived measures of how staff perceive their work-related stress and strain and patient safety on the one hand, and routine data measures of workload and quality of care (patient safety) on the other.We administered a written questionnaire to all physicians and nurses in the inpatient units at a German university hospital. The questionnaire was an amalgam of the Copenhagen Psychosocial Questionnaire (COPSOQ), the Copenhagen Burnout Inventory (CBI) scale to assess patient-related burnout of and portions of the Hospital Survey on Patient Safety Culture (HSPSC). Indicators from administrative data used to assess workload and patient-related work-strain were: amount of overtime worked, work intensity recording of nurses, cost weight, occupancy rate and DRG-related length of stay. Quality of care was assessed using readmission rates and disease-related length of stay. Univariate associations were tested with Pearson correlations.quantitative demands , emotional demands , and perceived role conflicts . Nurses’ work-intensity measures were associated with decreasing physician job satisfaction and with less favorable perceptions of the appropriateness of staffing . Both professional groups showed medium to strong associations between the morbidity measure (cost weight) and role conflicts; between occupancy rates and role clarity  and predictability of work ; and between length of stay and internal team functioning . Higher readmission rates were associated with lower perceived patient safety , inadequate staffing , and worse team functioning . Shorter disease-related length of stay was associated with better teamwork within units  and a lower risk of physician burnout .Response rate were 37% (224) for physicians and 39% (351) for nurses. Physicians’ overtime correlated strongly with perceived objective measures of overtime work as well as objective measures of workload correlated clearly with subjective work-related stress and strain. This suggests that objective workload measures (such as overtime worked) could be used to indirectly monitor job-related psychosocial strain on employees and, thus, improve not only staff wellbeing but also patient outcomes. On the other hand, listening to their personnel could help hospitals to improve patient (and employee) safety.Perceptions of hospital personnel regarding sub-optimal workplace safety and teamwork issues correlated with worse patient outcome measures. Furthermore,  The working environment in German hospitals has seen significant changes over the last few years. Due to the introduction of a DRG-based reimbursement-system, economics have increasingly influenced organization of care. Between 2004 and 2016, whilst the number of hospital beds decreased from 531.3 thousand to 498.7 thousand, the number of inpatients increased from 16.8 million to 19.5 million, and the average length of stay diminished from 8.7 to 7.3 days. Nurse-to-patient ratios have decreased over time and care, currently to 17.9 per 1000 cases [Demands on hospital staff are growing for various other reasons too, such as increasing complexity of diseases due to demographic change –5, growiTo guarantee patient and occupational safety in this challenging environment, appropriate psychosocial working conditions and strong leadership by hospital management and supervisors play central roles in counterbalancing increasing work demands –13. The perceived work-related stress and strain. Evidence on the importance of safety culture on patient outcomes in hospitals is growing as well [Managers increasingly utilise questionnaire-studies or regular staff surveys on  as well , 22. In  as well , 24. To  as well .Questionnaires looking at perceived working conditions offer more insights in organizational and managerial deficits and strengths than do crude administrative data: e.g. demands as defined in the demand-control-model by Karasek and Theorell, which include—in addition to the crude amount of work—the perceived pressure , 26. SieObjective workload measures are based on administrative data such as nurse-patient ratio, occupancy levels  and turnAdministrative data might be more readily and regularly available but methodological shortcomings, such as completeness and validity, have been highlighted –41. Alsoobjective workload measures and perceived stress and strain. [Therefore, understanding the association between the two measures (perceived and objective) might enable better prioritization of improvements to working conditions and patient  safety. However, there is little evidence for the correlation between  strain. We aim to assess the relation between perceived stress and strain of physicians and nurses and their workload, as measured by routine data. In addition, we want to test if perceived patient safety corresponds with objective non-disease-specific patient-safety and quality-of-care measures available in routine data. By doing so, we add to the limited existing literature concerning performance quality has rarely been linked to staff perceptions , 43. Corworking conditions, safety culture and patient safety in hospitals–what predicts the safety of the medication process WorkSafeMed) performed within two German university medical centers. The aim is to investigate the relationship between working conditions, safety culture and patient safety [This study is part of a cross-sectional, multicenter, mixed-methods study ) , 47, oneFrom COPSOQ, HSPSC-D and CBI : quantitative demands, emotional demands, influence at work, degree of freedom at work, meaning of work, workplace commitment, predictability, role clarity, role conflicts, social support, social relations, sense of community, job satisfaction, quality of leadership, work-privacy-conflict, staffing, adapted scale to assess patient-related burnout.(HSPSC-D) : teamwork within units, teamwork across units, staffing, handoffs & transitions, safety grade in the medication process, overall perceptions of patient safety, patient safety grade, frequency of events reported.  from units with more than 500 inpatients per year  were actively invited to take part in the survey  . For workload of nurses we used work intensity, an administrative measure  established in Germany, Switzerland, Austria and Italy, that monitors the proportion of non-patient-related activities in relation to available staff on a daily bases [The following indicators were used to assess ly bases , 53. It ly bases , 55. Thipatient-related work strain routinely available and commonly used proxies are used: length of stay, occupancy rates and morbidity [“relative cost weight” was used, which takes length of stay and resource utilization related to the individual diagnosis related group (DRG) into account and reflects the adjusted DRG-based diagnosis. DRG-related length of stay (LOS), mainly collected for assessing quality of care, is also known to correlate with severity of disease, therefore we used it in this explorative approach as an additional proxy for work strain [occupancy rates [For orbidity . For thek strain . In addicy rates  were asscy rates .The following indicators were used to assess quality:average 30-day readmission rates for all causes [DRG-related length of stay (LOS) as a proxy for quality of care, as longer than average LOS may reflect complications and thus potential quality problems [As an established measure indicating complications, we used l causes –59. In aproblems , 36.Data availability: Routine data were collected during the first 6 months of 2015 from all clinical departments, where both data sources (questionnaire and routine data) were available. Data was collected either pseudonymously (patient related data) or aggregated . Analysis was performed on an aggregate level, using averaged data per organizational unit . PatientData was analyzed as averages per organizational unit. All variables were examined for normal distribution. In cases of right skewed distributions logarithmic transformation led to an acceptable fit to the normal distribution. Univariate association between questionnaire results and routine data were tested with Pearson correlations. Correlations were tested separately for nurses and physicians, as well as for both professional groups together.First, we built defined three groups of theoretical associations . Next to 11 predefined study questions relating individual questionnaire scales to individual routine data measures , trends were reported at a 10% level. Without correction of multiple testing, correlations of 0.67 (n = 15) / 0.64 (n = 17) and 0,45 (n = 38) could be identified (i.e. significance for null hypothesis “correlation = 0”) with 80% power. Using Bonferroni correction for the 11 predefined study questions   for WindIndependent Ethics Committee (IEC) of the University of Tübingen . (Written) informed consent was sought from questionnaire participants, who were informed that the study was voluntary and that they could withdraw at any time. The questionnaire was distributed in every organizational unit accompanied by an explanation of privacy, data handling and voluntary participation. These explanations were also attached in front of the questionnaire. By sending back the questionnaire, the employee demonstrated his willingness to participate. This was consented by the employee committee. The Ethics committee waived the need for further consent, as the data was collected anonymously . Questionnaire data was analyzed anonymously. Routine controlling data for hospital performance was collected on an aggregated level and was therefore anonymous. Routine data on patients was available on an individual level , however accessible only as pseudonymized data. For analysis, aggregated data on organizational unit was used. As these analyses were considered part of quality assurance  by the data-security officer, no additional individual consent of patients was sought. (Writing from 4-16-2015/SR).Ethics approval was obtained from the The questionnaire was completed by 224 (37%) physicians and 351 (39%) invited nurses . The aveWe were able to include patient related routine data from overall 11,095 cases in 23 departments. Based on data availability, correlations could be calculated for nurses from 38 units, for physicians from 15 departments. Included cases per correlation may vary slightly according to available data. For two departments, only nursing (survey) data was available which was then used for the average values used in the correlation for both professions .physicians’ overtime hours and their perceived quantitative demands ; emotional demands ; and physicians’ perceived role conflicts . In addition, we found that increasing levels of doctors’ overtime correlated with increasing work-privacy conflicts .The strongest (significant) correlations were found for work intensity) did not show statistically significant correlations with any of the questionnaire scales reflecting quantitative or emotional demands. There was, however, a tendency for nursing workload to correspond with higher subjective influence at work .The objective workload of the nursing staff  and their perceptions of appropriateness of staffing   .cost weight (morbidity) . In line with that, both professional groups also showed weak inverse correlations between the morbidity measure and teamwork within units, which indicates how well team functioning is perceived. On the other hand, physicians’ answers indicated increasing role clarity with increasing morbidity of patients.We hypothesized, that sicker patients (as reflected by cost weight) induce higher work strain and workload for physicians and nurses. For rbidity)  we couldpatient-related burnout (CBI) showed a tendency for burnout to increase with patient morbidity . Physicians also indicated subjectively higher quantitative demands when caring for sicker patients , while nurses did not.Physicians’ answers concerning social support and the morbidity measure   .occupancy rates and perceived psychosocial stress and strain were found for role clarity  and predictability  in both professional groups , physicians’ job satisfaction increased . While physicians’ job satisfaction increased in a fully occupied unit environment, physicians’ burnout-scale decreased  with higher occupancy rates.Opposing trends between the professional groups could be detected for We also tested the correlation between quality of care reflected in routine data and perceived patient safety and related scales .medication safety  correlated significantly with the frequency of readmissions, perceived patient safety grade  correlated with readmissions for all staff. The same trend is visible for the multi-item scale for overall perception of patient safety .While only nurses’ judgments of frequency of events reported correlated negatively with readmissions.Physicians’ answers to Length of stay did not show any correlation with staff perceptions of patient-safety culture.readmission rates and staffing by both professional groups : with higher readmission rates, the personnel situation was increasingly perceived as insufficient (The strongest (negative) correlation was found between fficient teamwork across units . Physicians’ answers indicated the same for teamwork within units .Both professional groups also showed a negative correlation between readmissions and the perceived teamwork within their unit was correlated with decreasing patients´ length of stay . In addition, when patients´ stays were shorter than expected, physicians showed a higher risk of patient-related burnout (CBI) .The main research question was to explore as to whether perceived work stress and strain correlated with workload measures of routine data. Secondly, we wanted to understand as to whether perceived patient safety culture and perceived patient safety are correlated with routine data reflecting patient outcomes. Our results suggest that objectively measured workload is associated with staff members´ perceived work-related psychosocial stress and strain; secondly, the results showed that perceived worse elements of safety culture (namely teamwork) as well as patient-related burnout are associated with worse patient-related outcomes as measured by readmissions and longer stays. Also, perceived overall patient safety correlates with patient outcome measures.This supports the hypothesis that an increased objective work load can lead to more job-related stress and strain, which in turn can affect not only staff wellbeing, but also patient outcomes. Thus, improving working conditions could directly improve patient outcomes. The findings underline the importance of strategies to focus on safety culture in hospitals. Objective workload itself could be monitored by using routine data.overtime corresponded strongly with perceived quantitative demands. Obviously, the perception of the required pace and the inability to complete work  as depicted by the scale workload, is paralleled by actual worked overtime. In addition, physicians’ worked overtime corresponded with role conflicts and emotional demands. Therefore: not being able to perform work the way it should be, perceived contradictory or unnecessary demands and emotionally stressful situations go along with more worked overtime by physicians. Organization and team functioning not only play a major role in perceived workload but problems stemming from disorganization and deficiencies in teamwork may trigger costly and potentially unnecessary overtime. The relationship between teamwork, staff well-being and quality of care is well established [work-privacy conflicts which might be explained by the fact that overtime decreases time for family responsibilities and private life in general.Firstly, physicians’ workload as measured in documented ablished , 63. Botablished  Ochsmannmonitoring overtime in relation to objective workload could alert management to potential organizational shortcomings and without the need to survey personnel. Managers might find they can reduce costs by offering support measures, such as supervision of staff, that alleviate emotional stress and support optimal team function [From a management perspective, increasing worked overtime in a given unit might therefore point to a suboptimal working environment, especially if objective workload does not tally. Our results support the notion that unclear or conflicting roles and tasks, a lack of clear standards, and inefficient team communication can constitute potential barriers to smooth work processes. As a result, staff may spend more time coping with their tasks. Therefore, simply function .workload (measured with cost-weight and occupancy rates) showed associations with perceived poorer team functioning, increasing role conflicts, and lack of role clarity and predictability of work. Perceived deficits included less clearly described tasks and professional roles, reduced ability to predict job tasks and changes and more tasks that staff perceived as unnecessary (such as documentation). Thus, higher work-load and increasing pressure seem to make process-related problems more noticeable for staff or, in turn process-related problems are more likely to occur when workload is high. The importance of the team is also underlined by the fact that physicians showed lower job satisfaction and indicated insufficient staffing, when nurses’ work-intensity scores were higher. Thus, in our study we could show a relation between objective and perceived workload-measures. Kalisch and colleagues also found correlations between nurse-reported staffing adequacy and workload, and empirically derived working hours [In both professional groups increasing objective ng hours  but concmorbidity-related demands correlated with better perceived social support, greater influence at work among nurses and increasing role clarity among physicians, indicating that higher demands require or induce better ways to cope, whether because of mutual support or because of clearer definitions of the scope of work.On the other hand, higher work-related strain correlated to patient and process related objective workload measures  can help to detect stressors early and prevent loss of productivity and performance. Our results support the notion that management can improve efficiency and outcomes, whilst reducing overtime, by focussing on the team, The use of clear standards, defined roles and tasks is paramount and strong leadership with a focus on a healthy working environment is a prerequisite.The significant association between (perceived) appropriateness of staffing and patient outcomes in our data is consistent with the robust evidence, that patient to nurse ratios influence hospital mortality rates (e.g. ). In a sshorter length of stay are stronger than its quality effects. There is evidence that better physician wellbeing improves both the physicians’ health and quality of care [However, investing in staffing might not be sufficient. We found the quality indicators (readmission rates as well as length of stay) to be moderated by teamwork as much as by staffing. This relationship is in line with the work of Mark et.al. who found that nurses’ perception of quality of care is determined (amongst others) by leadership, staffing, resources, effective communication/collaboration, environment/culture and simplicity . On the  of care . Wallace of care  suggeste of care , 86, 87  of care  in whichlength of stay does not capture patient safety or quality of care as well as readmission rates, because it also reflects workload. At the same time, these results show that staff perceptions of patient safety seem to accurately reflect patient safety in their working environment.All our questionnaire scales related to perceived patient safety turned out to correlate as expected with higher readmission rates but not with length of stay. This may indicate that This study was an exploratory approach, therefore hypothesis driven rather than confirmatory. We were therefore rather unselective in our correlations. For the same reason, no prior calculation of sample size was performed and results of correlation analyses are shown without corrections for multiple testing. Although we relied on analysis of available administrative parameters, the questionnaire data was derived with well-established instruments. In addition, whilst the study included a broad range of hospital units , the data is limited to a single German university hospital, thus representing a specific setting. This is particularly relevant because administrative variables, such as overtime, are dependent on local policy and the regulatory framework. This cross-sectional study only analyzed correlations and therefore causal relations cannot be assessed. However, the associations we noted are supported in large part by existing literature.Further research is required to understand how routine data can be effectively used to inform management of prevailing structural team-related problems.bjective worked overtime as well as objective work-load measures correlated clearly with subjective work-related stress and strain, which suggests that monitoring workload in relation to overtime may be a useful tool to detect problems in team and leadership dynamics that may impede smooth work processes. This study has provided proof of concept. Our indicators fall short as proven final indicators, but we suggest pursuing the use of routine data for monitoring work-related stress and strain. Routine data, in contrast to questionnaire data, are readily available and therefore monitoring is easier to implement. To further test the responsiveness of the indicators, longitudinal assessments and different settings should be analysed.We showed a link between (objective) workload measures and perceived stress and strain, which, in turn, is known to correlate with work and patient safety as well as safety culture. We highlighted that oIn addition, patient outcomes were related to perceived patient safety as well as to perceived team performance. Taken together, these findings suggest that objective increased workload can lead to more job-related stress and strain, which in turn can impact not only staff wellbeing but also patient outcomes. Thus, improving working conditions could directly improve patient outcomes. This adds further weight to the importance of strategies that focus on safety culture in hospitals.S1 Dataset(SAV)Click here for additional data file.S2 Dataset(SAV)Click here for additional data file.S3 Dataset(SAV)Click here for additional data file.


Proper control of the phosphotyrosine content in signal transduction proteins is essential for normal cell behavior and is lost in many pathologies. Attempts to normalize aberrant tyrosine phosphorylation levels in disease states currently involve either the application of small compounds that inhibit tyrosine kinases (TKs) or the addition of growth factors or their mimetics to boost receptor-type TK activity. Therapies that target the TK enzymatic counterparts, the multi-enzyme family of protein tyrosine phosphatases (PTPs), are still lacking despite their undisputed involvement in human diseases. Efforts to pharmacologically modulate PTP activity have been frustrated by the conserved structure of the PTP catalytic core, providing a daunting problem with respect to target specificity. Over the years, however, many different protein interaction-based regulatory mechanisms that control PTP activity have been uncovered, providing alternative possibilities to control PTPs individually. Here, we review these regulatory principles, discuss existing biologics and proteinaceous compounds that affect PTP activity, and mention future opportunities to drug PTPs via these regulatory concepts. Cells integrate internal and external signals into appropriate adaptive responses. This signal processing should be timely and efficient, both from an economic and logistic point of view. Cells cannot rely on time-consuming de novo synthesis of RNA and protein components when fast responses are needed. Rather, they make use of a plethora of—often reversible—ways to modify biomolecules. One of the most abundant and best studied posttranslational protein modifications in signal transduction is reversible phosphorylation of serine, threonine and tyrosine residues. Protein phosphorylation is key in virtually all cellular processes , and espThe specific phosphorylation status of proteins within cells is tightly controlled by opposing kinase and phosphatase activities. Protein tyrosine kinases (TKs) add phosphate groups to selected tyrosine residues on proteins. Vice versa, members of the highly conserved protein tyrosine phosphatase (PTP) family dephosphorylate these phosphotyrosine sites. One should not conclude, however, that PTPs merely oppose TK functions; multiple examples exist that demonstrate that TKs and PTPs may also act in concert. Most phosphorylation events do not just target a single signaling pathway in the cell but have modulating effects that spread across multiple interconnected networks, thereby changing signaling specificity and outcome. Generally speaking, kinases are thought to control the amplitude of a certain signaling response and phosphatases are rather determining the response rate and duration ,5. 5R) containing an essential cysteine residue, which is responsible for removing the phosphate group from phosphorylated tyrosine residues. PTPs can be classified into several classes. Class I PTPs represent the largest group in which a distinction can be made between cytosolic non-receptor PTPs, transmembrane receptor PTPs (RPTPs) and dual-specificity PTPs (DUSPs). The dual-specificity subgroup can be further subdivided into MAPK phosphatases (MKPs), PTEN-related phosphatases (PTENs), phosphatases of regenerating liver (PRLs), myotubularin-related phosphatases (MTMRs) and atypical PTPs. The remaining cysteine-based classes are much smaller and consist of low-molecular weight (lmw) PTP (class II) and cell division cycle (cdc25) (class III). There is molecular evolutionary and enzymatic evidence to also include the haloacid dehalogenase (HAD), phosphoglycerate mutase (PGM) and acid phosphatase (ACP) families as PTPs. Instead of cysteine, these enzymes exploit aspartate (HAD) or histidine (PGM and ACP) in their PTP active site. In total, this brings the human PTP superfamily to the level of 125 protein-encoding genes . . PTPRZ1–However, there are more PDZ-based interactions that hold promise of proteinaceous drug development to treat glioblastomas. Recently, a bidentate molecule (113B7) that prevents the syntenin PDZ domain from binding targets like mutant EGFR (EGFRvIII) was shown to increase radiosensitivity and decrease growth of glioma tumors in vivo . Then, tFor decades, PTP enzymes have been reluctant to attempts to specifically interfere with their functioning. Increased knowledge on their contributions to diseases and on the regulatory principles that govern their actions is now aiding the removal of their stigma of being undruggable. We argue that, apart from initiatives to specifically target the catalytic PTP domains, strategies that aim at protein interactions mediated by these enzymes, notably—but not solely—PDZ domain-based interactions, provide appealing routes to modify PTP functioning. Of course, there are many hurdles. Especially when dealing with PPIs, one should realize that any post-translational modification, including phosphorylation, may alter binding specificities of target proteins or their partners. Furthermore, PPI inhibitors are of the competitive type, meaning that bioavailability and the reaching of the required dosage in target tissues represent tremendous challenges. Finally, in view of the complex interaction networks built by the plethora of biomolecules in cells, the targeting of protein–protein interactions inevitably will mean that the displaced components may then associate with promiscuous other interacting partners, with potential novel complications. On the other hand, by drugging just a single specific interaction in a target protein’s complex social network, one may cut off negative effects attributed to that single interaction while leaving remaining, beneficial interactions untouched. The current, massive studies towards protein–protein interactions and protein regulatory mechanisms will fuel these attempts to expand the toolbox to regulate and correct protein behavior, including that of the protein tyrosine phosphatase enzyme family. High hopes are on antibody-type biologicals that bind to and act via the extracellular portion of receptor-type PTPs and on cell-penetrating peptide-like compounds that specifically interfere with intracellular PTP-protein interactions.


Oral squamous cell carcinoma (OSCC), which encompasses the oral cavity-derived malignancies, is a devastating disease causing substantial morbidity and mortality in both men and women. It is the most common subtype of the head and neck squamous cell carcinoma (HNSCC), which is ranked the sixth most common malignancy worldwide. Despite promising advancements in the conventional therapeutic approaches currently available for patients with oral cancer, many drawbacks are still to be addressed; surgical resection leads to permanent disfigurement, altered sense of self and debilitating physiological consequences, while chemo- and radio-therapies result in significant toxicities, all affecting patient wellbeing and quality of life. Thus, the development of novel therapeutic approaches or modifications of current strategies is paramount to improve individual health outcomes and survival, while early tumour detection remains a priority and significant challenge. In recent years, drug delivery systems and chronotherapy have been developed as alternative methods aiming to enhance the benefits of the current anticancer therapies, while minimizing their undesirable toxic effects on the healthy non-cancerous cells. Targeted drug delivery systems have the potential to increase drug bioavailability and bio-distribution at the site of the primary tumour. This review confers current knowledge on the diverse drug delivery methods, potential carriers  and anticancer targeted approaches for oral squamous cell carcinoma treatment, with an emphasis on their clinical relevance in the era of precision medicine, circadian chronobiology and patient-centred health care. Oral cancer refers to tumors developed in the lips, hard palate, upper and lower alveolar ridges, anterior two-thirds of the tongue, sublingual area, buccal mucosa, retromolar trigons, and floor of the mouth . The majNew trends have recently emerged in the OSCC patient profile including younger patients (younger than 50 years), particularly those with human papillomavirus (HPV)-positive tumors ,11; a stOSCC has traditionally been associated with risk factors such as tobacco and alcohol consumption; however, HPV, a well-known cause of cervical cancer, has emerged in recent years as an etiological cause for a subset of head and neck squamous cell carcinoma (HNSCC), particularly in patients who lack the traditional risk factors ,18. The The HPV diagnosis is critical in planning treatment for oropharyngeal cancer (OPC) patients ,24,25. WOral squamous cell carcinoma is the second most common cancer in transplant patients  . The conThe oral, head, and neck cancer is an immunosuppressive disease (characterized by a lower absolute lymphocyte count and poor antigen-presenting function) that interferes with the patient’s natural immune response, preventing tumor cell recognition and immune-mediated clearance . ImmunotBecause HNSCC tumors have been shown to poorly present tumor antigen (TA) on the cell surface, monoclonal antibodies facilitating better TA presentation are one avenue for targeted therapeutics . NivolumDDS have been developed as an alternative method aiming to enhance the benefits of the current anticancer therapies, while minimizing their undesirable toxic effects on the healthy cells. For instance, the chemotherapeutic agents have several limitations in terms of oral bioavailability, stability in natural conditions, and non-specific bio-distribution, that decrease their therapeutic efficiency ,45; theiConventional therapeutic approaches need improvement in bioavailability and targeted delivery to the tumor site (for a pre-determined period) to overcome and prevent the adverse side effects of the drugs . Our groAn innovative approach to improve the efficacy of chemotherapeutic agents is the administration of drugs in a time-specific manner (chrono-chemotherapy). It is becoming evident that administration timing is as vital as the dosing amount of chemotherapy . The timAnother approach that showed promise in overcoming the complications of conventional anticancer agents while enhancing their therapeutic efficacy is the targeted drug delivery system consisting of natural and/or synthetic polymers for delivery of chemotherapeutic agents to the tumor site. Targeted drug delivery systems have the potential to increase drug bioavailability and bio-distribution at the site of the primary tumor. DDS is capable of releasing a bioactive molecule at a specific site with a specific delivery rate. Targeted DDS for oral cancer could thus improve patient compliance, enhance drug efficiency while reducing treatment duration, and consequently decrease healthcare expenses. In vivo studies have shown that targeted DDS can also improve the half-time of otherwise rapidly degradable drugs such as peptides and proteins, thus prolonging their local effects .Our review of the most promising anticancer drug delivery approaches is structured in three sections as follows: first, the conventional anticancer drugs are reviewed in regard to their oral administration and potential for DDS formulation; second, a brief background of commonly used carriers in DDS for oral cancer treatment is provided; and third, the potential of different drug delivery methods for OSCC is discussed.While most of the oncological treatments are traditionally administered intravenously, several anticancer drugs have recently been developed and approved by the USA Federal Drug Administration (FDA) for oral administration . Administration of chemotherapeutic drugs in the form of pill or gel is an attractive approach to enhance patient compliance. This method of delivery is also desirable when the treatment requires drug exposure for prolonged periods . Unfortuco-glycolic acid) (PLGA) in order to synthesize nanoparticles for PTX delivery; the montmorillonite-PLGA nanoparticles allowed for an enhanced cellular uptake and efficiency of PTX as compared to the PLGA nanoparticles alone, suggesting that the montmorillonite-PLGA nanoparticle formulation can extend the residence time of PTX in the GI tract [Paclitaxel (Taxol) is an antineoplastic agent which functions by cellular growth inhibition. Oral administration of PTX is challenging because of its low solubility and reduced permeability across the intestinal epithelium/mucosa that limit its absorption. When PTX is administered intravenously, which is the most common delivery method in the clinic, its distribution throughout the body is very extensive, causing severe side effects such as liver dysfunction . To incrGI tract .3O4 to be used as a vehicle for site-specific cisplatin delivery; their system, based on the encapsulated cisplatin into porous hollow nanoparticles of Fe3O4, not only protected cisplatin from deactivation by plasma proteins and other biomolecules before reaching the target site, but also provided control of the release rate of cisplatin by varying the nanoparticle’s pore size and pH [co-methyl methacrylate) micro-particles for controlled release of cisplatin, and their system enabled cisplatin to maintain its activity for prolonged periods [Cisplatin is a chemotherapeutic agent with a recognized benefit in the treatment of various human cancers, including oral, head and neck squamous cell carcinoma, bladder, lung, ovarian, breast, and testicular cancers. Cisplatin causes apoptosis (cell death) of cancer cells due to its ability to crosslink with purine bases on DNA, interfering with DNA repair mechanism, and causing DNA damage ,65. Becae and pH . Yan and periods . A cispl periods .Doxorubicin (DOX) is one of the most potent anticancer agents used for the treatment of numerous cancer types, because of its ability to target rapidly dividing cells, both cancerous and non-cancerous. Its toxicity on non-cancerous cells limits its application because it can result in cell death in major organs such as heart, brain, liver, and kidney ,70,71. DDocetaxel (DTX), an effective anticancer drug, is most commonly administered intravenously in cancer patients because of its highly hydrophobic property, but it has low oral bioavailability due to the P-glycoprotein (P-gp)-mediated efflux and first passes effect. To address these drawbacks, Sohail et al. synthesized a chitosan scaffold in which folic acid and thiol groups were grafted to chitosan to target cancer cells and improve permeation through the gastrointestinal tract . They alMethotrexate (MTX), an antimetabolite agent used in anticancer chemotherapy, is a folate antagonist which inhibits the synthesis of purines and pyrimidines, thereby causing inhibition of the malignant cells’ proliferation. MTX is used for the treatment of a variety of cancers, including oral, head, and neck cancer, acute lymphocytic leukemia, non-Hodgkin’s lymphoma, choriocarcinoma, osteosarcoma, and breast cancer ,76. Whenco-poly(methacrylic acid) hydrogel loaded with 5-FU, which enabled the release of 5-FU at pH 7.4, with the potential for being used as an oral drug delivery vehicle for 5-FU in cancer treatment, particularly colorectal cancer [Fluoropyrimidine 5-fluorouracil (5-FU), another FDA approved anticancer drug, inhibits essential biosynthesis processes or interferes with DNA or RNA, limiting their normal function. This drug has been effective in treating various types of cancer, including oral, head and neck cancer, colorectal, and breast cancer . Li et al cancer .Carrier-based drug delivery systems are used for controlled release of drugs while providing improved selectivity and effectiveness, and reduced side effects compared to the chemotherapeutic agents alone. Different carrier systems based on nanoparticles, nanolipids, and hydrogels are discussed here, each with unique advantages and disadvantages . AdditioThe use of nanotechnology in drug delivery has allowed for selective and safe methodologies for OSCC treatment ,92. NanoFor targeted drug delivery with improved biocompatibility and drug controlled release, nanoparticles fabricated from natural and synthetic polymer have received much attention . Polymer−7 [Endo et al. have used polymeric nanoparticles based on poly(ethylene glycol)-poly(glutamic acid) block copolymer to increase the anti-tumor effects and reduce the toxicity of cisplatin , the mos−7 ,103. The treatment of oral cancer cells with cisplatin-loaded nanoparticles (NC-6004) leads to the activation of the caspase-3 and caspase-7 pathways, which induce apoptosis . In vivoAdditional agents  have been investigated for their therapeutic benefit in oral cancer based on their ability to induce apoptosis and inhibit tumor cell proliferation ,104. To Adsorption of chitosan on PCL formed a muco-adhesive nanoemulsion, which showed an interaction between glycoprotein mucin and PCL nanoparticles. This system was evaluated by surface plasmon resonance. Better muco-adhesive properties lead to an increase in the residence time of the drug. The cytotoxic effect of these nanoparticles was evaluated in an in vitro study using an OSCC-derived cell line, SCC-9 that showed induction of apoptosis in tumoral cells. Furthermore, these polymeric nanoparticles encapsulating curcumin showed improved bioavailability  and imprInterestingly, dietary substances containing bioactive compounds may also have some ability to suppress cancer. Studies indicated that ellagic acid (a polyphenolic chemopreventive agent) has anti-cancerous, antioxidant, and antiviral properties. However, its usage is limited due to low oral bioavailability and water solubility . Bio-polInorganic nanoparticles have been extensively used in treatments due to their lower toxicity, higher tolerance towards organic solvents, and better bioavailability compared with the free drug . Inorgan2) to increase tissue penetration using NIR; these nanoparticles were used for targeting EGFRs on the surface of cancer cells using anti-EGFR-antibody conjugated with PEGylated TiO2-UCNs to inhibit tumor proliferation, invasion, angiogenesis, and metastasis. Anti-EGFR-PEG-TiO2-UCNs nanoparticles were characterized by TEM and a well-defined core-shell structure was observed with approximately 50 nm in diameter. Further, the composition of nanoparticles was confirmed by Energy-dispersive X-ray (EDX) spectroscopy showing formation of Na (Sodium), Y (Yttrium), F (Fluorine), Yb (Ytterbium), and Tm (Thulium) from the core nanocrystals and Ti (Titanium), Si (Silicon) and O (Oxygen) from the shell [2-UCNs showed no toxic side effects, whereas in vitro studies showed enhanced apoptosis and tumor growth inhibition [Recently, other therapeutic techniques, including photodynamic therapy (PDT), have been employed to increase the penetration of drugs deeper into tissues, required for the treatment of advanced and recurrent oral cancer . Lucky ehe shell . In vivohibition ,112.N,N′-bis  ethylenediamine iron ) for targeted delivery of anticancer agents. Since these particles were difficult to solubilize, they were suspended in water or saline after sonication. Iron–salen particles were characterized using DLS and TEM, showing size ranged 1.2–3 µm for unsonicated particles and 60–800 nm for sonicated particles. The sonication for approximately 6 hours reduced particle size (confirmed by TEM) with smooth edges of the particles as compared to the unsonicated particles. The sonicated Fe particles showed zeta potential value of −24.1 mV, thus confirming the stability of the colloidal dispersion [Drug delivery using nanoparticles allowed for increased concentration of therapeutic agents at the tumor site, which resulted in cancer cell inhibition with reduced toxicity on the surrounding non-cancerous healthy cells. Nevertheless, there are still challenges linked to carriers stability and fate in the human body, and their limited effective delivery remains problematic. To overcome some of these drawbacks, Eguchi et al. prepared innovative magnetic nanoparticles consisting of μ-oxo spersion .Sato et al. used Fe nanoparticles with average size of 200 nm for targeted delivery of anticancer agents. These nanoparticles were sonicated for 30 min and were suspended in normal saline. Alternating magnetic field (AMF) combining chemotherapy and hyperthermia was used to heat Fe nanoparticles and resulted in increased induction of cancer cell apoptosis and better carrier stability, as compared to individual chemotherapy or magnetic guided delivery. Fe nanoparticles were useful for controlled drug delivery and hyperthermia therapy, with an increase in anti-cancer therapeutic efficacy and reduced toxicity .Other inorganic nanoparticles systems, such as mesoporous silica nanoparticles (MSNP), showed promise for cancer therapy. These nanoparticles’ advantages include high porosity, biocompatibility, and amenability for surface functionalization . The porCombinational drug treatment is recognized for its increased therapeutic benefits. Targeted drug delivery offers improved therapeutic efficacy with reduced toxicity. Quinacrine (QC) is an anticancer agent that is also used as an antimalarial drug; it has shown therapeutic benefits in breast, lung, colon, and renal cell carcinoma. Despite these positive outcomes, QC clinical applications are limited due to its poor bioavailability and various side effects, including skin rash and pigmentation, and immunological complications . InorganPolymeric nanoparticles’ cytotoxicity, due to low internalization into the tumor cells, restricts their therapeutic efficiency ,86. SoliOne limitation of nanoparticles prepared from solid lipids is their crystalline structure, which allows for only limited space to accommodate drugs. Nanostructured lipid carriers (NLCs) have been designed and tested in cancer therapy to overcome this limitation. These NLCs consist of both solid and liquid lipids in a core matrix, thereby distorting the crystal structure and providing space for drugs to be encapsulated in amorphous clusters ,121. ThuHydrogels are three-dimensional (3D) mesh structures of hydrophilic fibers that contain a large amount of water or biological fluids. Hydrogels resemble the soft body tissues and are capable of encapsulating drugs and biomolecules such as proteins and genetic materials . DependiHydrogels act as localized, targeted drug delivery systems and offer some advantages when juxtaposed with active and passive targeting by using nanocarriers . For insMoreover, hydrogels allow for co-administration of multiple drugs with synergistic anti-cancer effects and decreased drug resistance ,130. In Exosomes are membranous vesicles with sizes between 40–120 nm that are secreted by different cells, such as dendritic cells, macrophages, mesenchymal stem cells, endothelial, and epithelial cells, into the extracellular space ,140,141.The treatment options for advanced OSCC are limited and suboptimal. Conventional therapeutic approaches  significantly impact patient’ wellbeing and quality of life. Thus, there is an imperative requirement for new therapeutic methods with reduced side effects and systemic toxicity. Several controlled drug delivery and release strategies have been developed to overcome the current challenges associated with the parenteral  administration of chemotherapeutic agents. These strategies include: the administration of chemotherapeutics via intra-tumoral injection; local delivery; photo-thermal administration using drug-loaded nanoparticles; and ultra-sonoporation using microbubbles . These aOne approach is local intra-tumoral administration ,147. Li Local drug delivery is a tumor-targeted approach that delivers the drug to the proximity of the tumor. With this approach, the drugs enter the systemic circulation to a lesser extent compared with other administration routes, thus limiting the adverse side effects of the drugs on healthy cells . For exaLocal delivery of anticancer drugs to the oral cavity provides a convenient and safe local administration, with benefit of rapid turnover of the oral mucosa; this allows for a rapid self-repair after given damage and is a significant advantage that helps alleviate the adverse effects caused by long-term local drug delivery . The majPhototherapy is a minimally invasive method that is commonly used in the treatment of neoplastic disease. The first phototherapeutic technique is photodynamic therapy (PDT), consisting of administration of a photosensitizing agent followed by irradiation, which is absorbed by the agent at a specific wavelength. The photosensitizer generates reactive oxygen species (ROS) following the utilization of near-infrared (NIR) light, which results in the apoptosis of cancer cells. This process has proven to be efficient in killing the cancer cells, with the limitation that accumulation of the photosensitizer in the tumor is relatively low ,152. PhoDrug delivery systems (DDS) can improve the phototherapy techniques and address their limitations. Recent studies have focused on incorporating chemotherapeutic agents and photosensitizers or light absorbing agents into nanocarriers. After delivery of these agents at the tumor site, local irradiation has resulted in the killing of the cancerous cells and tumor shrinkage. Current research studies are focused on the use of magnetic nanoparticles for targeting or tracking cancer cells by magnetic resonance imaging (MRI) ,156,157.He et al. combined photodynamic therapy (PDT) with chemotherapy to simultaneously release anticancer and photosensitizer drugs at the tumor site for the treatment of resistant head and neck cancer. Coordination polymer (NCP)-based core-shell nanoparticles were prepared and loaded with cisplatin and the photosensitizer pyrolipid. They performed in vivo studies, where mice were treated with a combination of nanoparticles loaded with cisplatin and pyrolipid; a remarkable tumor reduction (83%) occurred in cisplatin-resistant SQ20B subcutaneous xenograft murine HNSCC model after the combined treatment of loaded nanoparticles and irradiation. This system of delivery allowed for high loadings of cisplatin and pyrolipid to be locally released after irradiation at the tumor site, with increased anticancer effects as compared to monotherapy .Microbubbles are micrometer-sized (1–2 µm) gas bubbles that are used as ultrasound contrast agents. The injection of microbubbles into blood circulation improves the contrast of ultrasound images. In addition to their diagnostic usage, the combination of microbubbles and ultrasound can be used in local drug delivery for the treatment of cancer. Microbubbles can be targeted to specific tumor sites by incorporation of ligands or monoclonal antibodies binding to receptors expressed on cancer cell membranes. The combination of chemotherapeutic agents with microbubble-mediated ultrasound therapy increases drug uptake in targeted tissues through so-called ‘sonoporation’, improves the drugs’ biodistribution and decreases their systemic toxicity ,160,161.One crucial strategy for the treatment of HNSCC is the inhibition of EGFR signaling, but current methods cannot suppress this signaling completely. EGFR inhibition can occur through RNA interference by using microbubbles as nucleic acid delivery vectors. Microbubbles delivered to the site get ruptured by ultrasound-targeted microbubble destruction (UTMD) resulting in drug release from the microbubbles’ shell to the insonified area .Recently, Hirabayashi et al. developed anti-EGFR antibody-conjugated microbubbles for colon squamous cell carcinoma treatment. In in vivo studies, anti-EGFR-microbubbles were injected directly into the tumor, while the anticancer drug bleomycin (BLM) was injected via the tail vein. The findings of this study showed that anti-EGFR-microbubbles bound to EGFR on Ca9-22 cells, and the BLM uptake was increased following anti-EGFR-microbubbles binding to cancerous cells. This system is promising to enable effective targeted delivery of anticancer drugs into oral cancer cells .Carson et al. highlighted the potential use of microbubbles as carriers of anti-EGFR siRNA along with ultrasound-targeted microbubble destruction (UTMD) in SCC-VII-induced murine squamous cell carcinoma model. Delivery of microbubbles to the tumor site, where they were ruptured by UTMD and resulted in drug release from the microbubbles to the insonified area, led to tumor growth suppression in mice with OSCC . Recent A novel immunotherapy strategy involves using small molecules as monotherapy or combined with other anticancer therapies . The maiThere is also promising burgeoning research on immunotherapy and gene therapy for oral cancer treatment, and these therapies can also benefit from DDS ,182,183.The major challenge in the management of HNSCC patients today is the development of the evasive cancer cell resistance to conventional therapies. Drug delivery systems employed for the administration of chemotherapeutic agents have shown promise in the abilities to overcome the limitations of the conventional anticancer therapeutic approaches. Drug delivery systems for oral cancer consist of three major components: the anticancer agents (single or multiple); carriers to encapsulate the agents; and the methods of delivering the agents to the tumor site. The carriers can be chosen among natural, synthetic, or a combination of materials. They can be prepared in the form of hydrogels or nanocarriers, including nanoparticles and nanolipids. New drug delivery approaches in oral cancer focused on intratumoral or local drug delivery, photothermal therapies combined with DDS, and delivery using ultrasound-mediated microbubbles. Even though controlled drug delivery systems have been around for more than 30 years, improving clinical efficiency and release profiles of anti-cancer drugs as well as lowering their side effects remains a challenge. One of the main hindrances for the commercialization of these systems is the low production reproducibility. Currently, most research investigations are still focused on in vitro or in vivo studies, whereas only a few systems have been implemented into the clinic . A nano-


Myelin sheaths in the central nervous system (CNS) insulate axons and thereby allow saltatory nerve conduction, which is a prerequisite for complex brain function. Multiple sclerosis (MS), the most common inflammatory autoimmune disease of the CNS, leads to the destruction of myelin sheaths and the myelin-producing oligodendrocytes, thus leaving behind demyelinated axons prone to injury and degeneration. Clinically, this process manifests itself in significant neurological symptoms and disability. Resident oligodendroglial precursor cells (OPCs) and neural stem cells (NSCs) are present in the adult brain, and can differentiate into mature oligodendrocytes which then remyelinate the demyelinated axons. However, for multiple reasons, in MS the regenerative capacity of these cell populations diminishes significantly over time, ultimately leading to neurodegeneration, which currently remains untreatable. In addition, microglial cells, the resident innate immune cells of the CNS, can contribute further to inflammatory and degenerative axonal damage. Here, we review the molecular factors contributing to remyelination failure in MS by inhibiting OPC and NSC differentiation or modulating microglial behavior. Aside from multifocal inflammation and demyelination, neurodegeneration is one of the hallmarks of multiple sclerosis (MS). It represents the key factor driving clinical disability and the diminished quality of life in this commonest autoimmune disease of the central nervous system (CNS). The relapsing subtypes of MS (RMS) have become rather well treatable with a range of drugs. By contrast, progressive MS (PMS), characterized by the steady accumulation of neurological deficits and disability, remains a therapeutic challenge. Demyelination resulting from the autoimmune damage of oligodendrocytes and a loss of myelin sheaths lies at the core of MS. Myelin sheaths, which insulate axons and guarantee safe and reliable impulse propagation, are critical for normal neural function. Their loss leads to reduced axonal integrity, which over time, results in neuronal fallout, and consequently to fixed functional deficits. Partial replacement of lost oligodendrocytes and the (re)establishment of myelin sheaths around denuded axons can occur as a result of the activation, recruitment and differentiation of resident oligodendroglial precursor cells (OPCs) and neural stem cells (NSCs). These cells can differentiate and mature into myelin-sheath forming oligodendrocytes— a repair process commonly referred to as remyelination . HoweverOne of the most important cell types involved in these mechanisms are microglia, the resident innate immune cells of the CNS which modulate particularly OPC homeostasis, but also directly contribute to axonal degeneration. In this review, we investigate which factors influence OPC and NSC differentiation, with particular attention to the role of microglia in these processes see .Representing 5–8% of the total cell population of the adult brain, resident OPCs are found widely distributed throughout gray and white matter, and provide a source for myelin repair following CNS injury ,7. HowevTechnically, one of the most effective approaches to neutralize potential inhibitors of OPC differentiation is targeted antibody therapy. An antibody that was already shown to have a good safety profile in phase 1 clinical trials for MS and amyotrophic lateral sclerosis (ALS) is ozanezumab . Ozanezumab is a humanized monoclonal antibody targeting the myelin-associated neurite outgrowth inhibitor NogoA. The histones of NogoA-expressing oligodendrocytes are highly acetylated, which is associated with an increased transcription of OPC differentiation inhibitors . ClinicaElezanumab is another humanized monoclonal antibody currently tested in phase 2 clinical trials for RMS (NCT03737851) and PMS (NCT03737812). This antibody is directed against the membrane-bound repulsive guidance molecule A (RGMa), which promotes inflammation and inhibits CNS regeneration and remyelination mainly via the multifunctional target receptor neogenin . Anti-RGOpicinumab, another monoclonal antibody, was also investigated in several clinical trials assessing its effectiveness and safety in MS patients. This antibody is directed against the Nogo-receptor interacting protein LINGO-1, which was found to negatively regulate OPC differentiation by activating RhoA and inhibiting the Akt signaling pathways . The phaFinally, the humanized anti-pHERV-W Env antibody temelimab yielded promising results in a recently completed phase 2b study in RMS (NCT02782858) after a previous phase 2a study had already yielded encouraging results . TemelimIn the past years, growing interest has focused on endogenous and transplanted neural stem cells (NSCs) and their potential to provide oligodendrocyte replacement and to mediate myelin repair. NSCs are multipotent cells which can self-renew and differentiate into neurons and glial cells ,51,52, m14C incorporation into genomic DNA (a result of nuclear tests during the Cold War) demonstrated that newly generated oligodendrocytes can still be detected around the lateral wall of the adult human SVZ [As already mentioned above, aging could play a role in failing remyelination. In this context it was shown that the aged SVZ suffers from a reduced number of ventricle-contacting astrocytes. These cells are the precursors for so-called transit-amplifying cells (TAPs), which are highly proliferative, and can give rise to newly differentiated oligodendrocytes. This is in line with the recent suggestion that human cellular senescence is responsible for a diminished remyelination potential in progressive MS patients . Moreoveuman SVZ , therebyIn the mouse MS model, EAE inflammation was demonstrated to modulate NSC differentiation ,76,77, aWhile several EAE studies provide evidence that NSCs can modulate chemokine levels, resulting in an impaired recruitment of immune cells to the CNS ,80, thesA number of different factors and signaling pathways which modulate NSC-derived oligodendrogenesis have been described (summarized in ). The maOPC and NSC homeostasis cannot be seen in isolation from other cell populations or physiological processes. In this regard, the innate immune system, i.e., resident microglia and peripherally-derived infiltrating macrophages, have been shown to be essential for remyelination. This includes axon regeneration, the clearance of myelin debris and the release of neurotrophic factors that promote OPC differentiation . MicroglPhagocytosis of myelin debris in the MS brain is essential for the initiation of neuro-repair as myelin debris inhibits OPC differentiation and, by doing so, remyelination . Among oBesides inefficient myelin debris clearance, failing paracrine stimulation of OPC differentiation by microglia is another key factor contributing to inefficient remyelination in MS. In this context, it was discovered that fibronectin aggregates accumulate in the extracellular matrix (EZM) during chronic demyelination processes and impede remyelination via inhibiting oligodendrocyte differentiation. Matrix metalloproteinases (MMPs) on the other hand, can modulate the EZM and are able to split fibronectin—as it is the case for MMP7. Microglia were identified as a major source of the MMP7 proenzyme proMMP7, which is reduced in chronic active and inactive MS lesions correlating with higher amounts of fibronectin aggregates disrupting OPC differentiation capacity . In geneWhile the past years have seen the approval of highly potent immunomodulatory drugs which led to a paradigm shift in the treatment of RMS, therapies that stimulate myelin repair and prevent neurodegeneration are still unavailable. However, even though ultimately rather ineffective, the brain’s own repair mechanisms provide us with helpful leads as to where to start the search for such therapies. Of course, in order to claim credible relevance for MS, pre-clinical studies which aim to identify promising molecules have to be conducted in a context as close as possible to the human paradigm, i.e., in human cells and/or in human tissue, which are, of course, difficult to procure. Nonetheless, the quest for myelin repair enhancement in MS has already prompted the initiation of several trials assessing the clinical effectiveness of molecules known to inhibit or stimulate OPC differentiation . Of note


Non-invasive brain stimulation (NIBS) has been widely used as a research tool to modulate cortical excitability of motor as well as non-motor areas, including auditory or language-related areas. NIBS, especially transcranial magnetic stimulation (TMS) and transcranial direct current stimulation, have also been used in clinical settings, with however variable therapeutic outcome, highlighting the need to better understand the mechanisms underlying NIBS techniques. TMS was initially used to address causality between specific brain areas and related behavior, such as language production, providing non-invasive alternatives to lesion studies. Recent literature however suggests that the relationship is not as straightforward as originally thought, and that TMS can show both linear and non-linear modulation of brain responses, highlighting complex network dynamics. In particular, in the last decade, NIBS studies have enabled further advances in our understanding of auditory processing and its underlying functional organization. For instance, NIBS studies showed that even when only one auditory cortex is stimulated unilaterally, bilateral modulation may result, thereby highlighting the influence of functional connectivity between auditory cortices. Additional neuromodulation techniques such as transcranial alternating current stimulation or transcranial random noise stimulation have been used to target frequency-specific neural oscillations of the auditory cortex, thereby providing further insight into modulation of auditory functions. All these NIBS techniques offer different perspectives into the function and organization of auditory cortex. However, further research should be carried out to assess the mode of action and long-term effects of NIBS to optimize their use in clinical settings. Non-invasive brain stimulation (NIBS) has recently seen a surge of interest to provide understanding about the functional properties and interactions of cortical systems. With their ability to either inhibit or enhance cortical excitability, NIBS techniques are a promising tool in both research and clinical settings. Various types of NIBS are available: transcranial direct current stimulation (tDCS), transcranial magnetic stimulation (TMS), transcranial alternating current stimulation (tACS), or transcranial random noise stimulation (tRNS), which differ in their mode of action.Here, we will review outcomes from NIBS studies in the context of their application to the auditory cortex and related systems. We will especially discuss how different NIBS techniques provide us with different perspectives in examining auditory processing, ranging from behavior to neural activity and structural organization. In addition, we will review how NIBS can be used to inform about the neural dynamics of auditory processing at basic processing levels, such as pitch, to higher order levels such as those involving speech. Finally, we discuss the potential of NIBS as a treatment tool for auditory-related disorders and highlight the need of basic research to increase our understanding of NIBS mechanisms.Some of the first NIBS studies to investigate auditory processing used tDCS and assessed its effects on behavior . tDCS isThe role of tDCS polarity was shown over the motor cortex, with positive stimulation  increasing neuronal excitability  and negaTranscranial direct current stimulation polarity-specific effects on auditory cortex are less clear. For instance, Changes in tDCS-induced cortical excitability depend also on the stimulation timing. In offline tDCS, stimulation is applied at rest, usually before the task is undertaken; whereas in online tDCS, stimulation is applied while a task is being executed. It is also common to use a combination of online and offline tDCS. The latter approach can have several variants, for example, tDCS and task stimuli start at the same time , or the In The different outcomes of the Matsushita and Tang’s vs. Mathys’ studies could be related to the stimulation timing  relative to the task being performed or to the use of different stimulation parameters . It has indeed been shown that 1-mA intensity caused conventional polarity-specific modulation of neural excitability , whereas 2 mA led to increased excitability from both stimulation polarities . This coAnother issue which is not well understood is the asymmetry of tDCS-related effects in the auditory cortex. Neuroimaging findings for functional asymmetries in auditory cortices have been frequently reported, but there is still debate about their nature and whether they are directly or indirectly related to structural specialization . For insRelatively few NIBS studies have examined asymmetries in the auditory cortex. As already mentioned above, several tDCS studies showed more impairment when stimulation was applied over the right compared to the left auditory cortex, in accordance with a prominent role for the right auditory cortex in pitch discrimination. In addition, These findings also highlight the need to use neuroimaging to guide NIBS applications. This consideration is especially relevant since variations in stimulus patterns  or the use of differently structured tonal patterns may differentially recruit primary and non-primary auditory cortical regions , affectiIn addition, the combination of NIBS and neuroimaging enables one to assess individual differences in structural and functional organization of auditory networks, and might help to reduce the relatively high inter-subject variability of NIBS-induced changes on behavior . Future studies should therefore systematically assess functional organization and connectivity in order to better understand changes induced by tDCS, or any other stimulation, at a whole-brain  and at individual levels.Transcranial magnetic stimulation uses magnetic fields to induce electrical current in spatially restricted cortical regions. Compared with tDCS, TMS provides a better spatial resolution; when used over the motor cortex, it also allows the quantification of motor-evoked potentials (MEPs), a measure of the excitability of the motor system, which tDCS does not. TMS has however some disadvantages, such as evoked facial muscle twitches and loud clicking noise which may introduce confounding effects when applied over the auditory cortex, especially at high stimulation frequencies, and therefore need to be accounted for.Similar to tDCS, TMS can have inhibitory or excitatory effects on cortical excitability, but different from tDCS, this feature is not polarity-related but rather frequency-related. Studies using TMS on the motor or visual cortices have shown that low-frequency TMS (1 Hz) decreases motor and visual cortical excitability  and highIn addition to the frequency of stimulation, TMS effects depend also on the duration and the pattern of stimulation. For instance, single-pulse TMS delivers a single magnetic pulse and its effect is transient, whereas repetitive TMS (rTMS) delivers repeated single magnetic pulses and is able to modulate cortical activity beyond the stimulation period . Paired-More recently, theta burst stimulation (TBS) methods have been developed based on experimental neurophysiology for inducing LTD- or LTP-like effects depending on the pattern of stimulation . TBS conThe effects of TMS parameters  on non-motor areas, such as language or auditory cortices are however still unclear. For example, Such facilitatory effects on language processing after rTMS applied over the temporoparietal cortex have been reproduced for other stimulation frequencies such as 10 or 20 Hz . DiffereTo date, only a few studies have used functional neuroimaging to map TMS-induced effects, especially in the auditory cortex. These studies showed that after TMS applied over the auditory cortex, functional interactions occur at a large-scale level, reaching brain areas in the contralateral hemisphere . For insSuch interhemispheric interaction mechanisms have also been shown for brain areas involved in language comprehension. vice versa .In order to dissociate task-related compensatory processes from TMS-induced effects, Although there is debate regarding structural linkage and resting-state functional connectivity , such fiFunctional asymmetries in the auditory cortex activity at rest were also previously reported using positron emission tomography. For instance, Knowledge about baseline connectivity dynamics is highly valuable since it has the potential to predict behavioral performance in perception and cognitive tasks  and has A recent development in the field of NIBS is the use of tACS  and tRNSSuch techniques seem particularly relevant considering that gamma band oscillations have been associated with the processing of auditory information at the level of the auditory cortex . Using fStimulation of auditory areas outside of the temporal cortex has recently been shown to be especially relevant for auditory working memory. The potential of NIBS techniques to boost sensory or cognitive functions such as auditory or language processing in a safe and non-invasive fashion motivated its use in the developing brain. The use of these neuro-enhancement techniques in pediatric populations raises however ethical concerns , particuAn additional point regarding NIBS applications, particularly relevant for therapy, concerns its after-effects. The physiological bases of NIBS after-effects have not yet been clearly identified. Many arguments support the idea that the mechanisms underlying NIBS after-effects could resemble LTD and LTP described in the human auditory cortex using fMRI  or EEG .Little is known however, because most studies have examined lasting effects only on the motor cortex, and focused on the immediate effects induced after the stimulation. For instance, using tDCS over the motor cortex, perturbation in neurophysiological measures was shown to substantially outlast the stimulation period by up to 90 min . Using cLong-lasting changes in cortical excitability were also shown with tRNS, such that 10-min tRNS lasted up to 60 min , and 5-mSimilarly, after-effects on cortical excitability have been reported with TMS and have been related to the frequency used. Using 50-Hz bursts of TMS , decreased cortical excitability was reported lasting up to 60 min . In addiEffects of NIBS on auditory or language functions might not be as long lasting as for the motor cortex or more complex to assess, possibly related to ongoing cognitive processes and deserve thorough investigation using neuroplasticity markers. For instance, 20-Hz rTMS applied over the left temporal cortex induced performance facilitation lasting up to 2 min . In AndoCurrent NIBS findings in basic research highlight inter-individual variability related to structure and function of the auditory cortex, thereby emphasizing the importance of assessing individual measures. This information is especially important for optimizing therapeutic outcome in clinical settings, e.g., tinnitus or auditory hallucinations in schizophrenia patients, since the lateralization and duration of the disorder, frequency of the occurrence of the symptoms, might affect functional organization in the auditory pathway and therefore after-effects of NIBS.Therapeutic use of NIBS for tinnitus suppression was investigated using TMS applied over the auditory cortex. Some studies compared various rTMS protocols  and showed greatest reduction of tinnitus loudness for both iTBS and 1-Hz rTMS . The posNon-invasive brain stimulation techniques such as tDCS have been a technique of choice in many clinical and research settings because it is portable, painless, and inexpensive compared with other NIBS techniques. tACS, tRNS, and tDCS have however a relatively low spatial precision, due to the large spatial distribution of the electrical current flow produced by the electrodes and is furthermore accentuated by the anatomical variability of the targeted brain structures . To overIt is however still unclear if modulation of auditory functions will benefit from higher spatial accuracy. Present knowledge using TMS show that even targeting “accurately” the auditory cortex within a 2-cm resolution has an effect at a large scale reaching remote interconnected areas. New directions for NIBS might be therefore oriented toward “guided cortical plasticity,” consisting in combining NIBS-induced unspecific neural noise with specific behavioral training. Such approach has been successfully used to improve various perceptual or cognitive abilities in both healthy participants and in patients .Other NIBS techniques have also been recently developed which also hold promise for advancement into our understanding of cognitive function. For instance, transcranial pulsed current stimulation tPCS; , which cWe highlighted the complexity of the cortical dynamics and functional interactions in the auditory cortex. We also emphasized the importance of NIBS approaches in basic science research, since they helped to better understand local and remote functional interactions in auditory areas, such as the asymmetric communications between auditory cortices. Such information is crucial and could help to optimize the application of NIBS in clinical settings. We support the combined use of NIBS with functional imaging techniques, such as fMRI or EEG/MEG to better understand the physiological consequences of stimulation of neural networks and to account for individual differences. Current findings also suggest that individual differences in structure and function could be predictive factors of NIBS outcome. Therefore, assessing functional organization and connectivity in auditory-related disorders should provide a better understanding of NIBS-induced propagation mechanisms in disease.All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.