Can the prophylactic human papillomavirus vaccine (Gardasil-9) reduce the risk of anal and vulvar high-grade squamous intraepithelial lesion (HSIL) recurrence after treatment of the prevalent lesion?This trial protocol describes a randomized clinical trial targeting enrollment of 345 HIV-positive and HIV-negative adults with history of anal or vulvar HSIL. The trial seeks to evaluate whether the human papillomavirus vaccine can reduce the risk of recurrence by 50% in previously unvaccinated individuals with a prior histologically confirmed anal or vulvar HSIL diagnosis.If successful, the licensed human papillomavirus vaccine could be incorporated with other treatment for patients with anal and vulvar HSIL to reduce the high rate of HSIL recurrence. This trial protocol describes a randomized clinical trial to assess the effectiveness of a human papillomavirus vaccine to reduce the risk of anal and vulvar high-grade squamous intraepithelial lesion recurrence after treatment. Human papillomavirus (HPV), particularly HPV type 16, causes most anal and vulvar high-grade squamous intraepithelial lesions (HSIL), which are precursors to cancer. After initial treatment of HSIL, more than 30% of patients will have disease recurrence, with even higher recurrence among HIV-positive individuals and men who have sex with men. Recurrences can be debilitating and lead to significant morbidity and medical expense. Observational studies suggest a possible therapeutic benefit of the licensed HPV vaccines in reducing recurrent lesions in previously infected persons.To test whether the licensed prophylactic HPV vaccine (Gardasil-9) can reduce the risk of HSIL recurrence by 50% in previously unvaccinated individuals recently treated for anal or vulvar HSIL.This is a trial protocol for a randomized, double-blind, placebo-controlled, proof-of-concept clinical trial. Eligible participants are aged 27 to 69 at study start and have not received prior HPV vaccination, have had anal or vulvar HSIL diagnosed on or after January 1, 2014, and have no evidence of HSIL recurrence at screening. Persons infected with HIV are eligible for the study provided they are receiving antiretroviral therapy. Target enrollment is 345 individuals. The primary outcome is time to histopathologically confirmed recurrence of HSIL. Differences in the risk for recurrence of HSIL will be evaluated using Cox proportional hazard models. Additional analyses include (1) frequency of HSIL recurrence; (2) role of HPV antibodies in deterring recurrence; (3) role of HPV persistence in recurrence, as measured by HPV genotype or HPV-16 variant lineage determined using swab samples collected at months 0, 18, and 36; and (4) incidence of adverse events. The study will be conducted at the University of Washington Virology Research Clinic from 2017 through 2022. Participants will be followed up for up to 36 months in the clinic, and up to 42 months by telephone.Management of persistent or rapidly recurring anogenital HSIL remains challenging. Results from this study will provide evidence on whether incorporating the nonavalent HPV vaccine into routine care can decrease recurrence of anal and vulvar HSIL.NCT03051516ClinicalTrials.gov identifier:  Treatment of anal and vulvar HSIL is variable across centers and includes ablation, excision, or topical therapies with immunomodulating agents. Following treatment for HSIL at either site, approximately 50% of lesions will recur within 5 years following treatment.2116Persistent HPV infection and high-grade squamous intraepithelial lesions (HSIL) are presumed to lead to HPV-related anal and vulvar cancer, analogous to the natural history of cervical HPV infections leading to cervical cancer.22 As demonstrated by studies using the 4vHPV vaccine among HIV-infected patients, the prophylactic vaccine (Gardasil-4) is also safe and immunogenic in this group of persons.24 Although HPV vaccination in persons older than 26 years is not routinely recommended by US guidelines, clinical trials27 demonstrated that the 2vHPV and 4vHPV vaccines are safe, immunogenic, and highly effective in women up to age 55 years. Safety, tolerability, and immunogenicity trials of the 9vHPV vaccine in adult immunocompromised participants are currently ongoing .The prophylactic bivalent (2vHPV), quadrivalent (4vHPV), and nonavalent (9vHPV) HPV vaccines are safe and effective in reducing HPV-driven cervical cancers by preventing HPV acquisition in HPV-naive persons.31 suggest that the vaccine may also reduce the risk of HSIL recurrence in previously infected patients. The exact protective mechanism in infected persons is not well understood. One hypothesis is that the vaccine will prevent new infections.30 The antibody response elicited with the HPV vaccine may prevent cell reinfection and subsequent neoplasia.33 In addition, the HPV vaccine stimulates cell-mediated immunity,36 which may also play a role in preventing recurrent infection.Several observational studiesThe VIVA  trial is a randomized, double-blind, placebo-controlled, proof-of-concept clinical trial . The objNCT03051516). Eligible participants include men and women who meet the following criteria: (1) age 27 to 69 years; (2) histologically confirmed anal or vulvar HSIL (AIN2/3 or VIN2/3) diagnosed on or after January 1, 2014, with p16Ink4 testing if needed to confirm HSIL as determined by the study pathologist; (3) 2 or more months since last therapy for HSIL; (4) no clinical or histological evidence of HSIL on screening examination, with patients whose screening visit reveals HSIL eligible to be rescreened 2 or more months after therapy; (5) residence in the area and willing to attend all visits; (6) for women of childbearing potential, agreement to use effective contraception through study month 7; (7) for HIV-positive persons, treatment with antiretroviral therapy for at least 6 months prior to enrollment; and (8) participant written informed consent and agreement to sign medical records release forms. Criteria for exclusion are the following: (1) pregnancy; (2) chemotherapy ; (3) history of invasive HPV-related cancer; (4) unstable medical conditions ; (5) prior HPV vaccination; (6) allergy or intolerance to lidocaine; (7) current participation in an HPV-related interventional research study ; and (8) any other condition that, in the opinion of the investigators, may compromise the participant's ability to follow study procedures and safely complete the study . Note that patients with immunosuppressive conditions, eg, solid-organ transplant, are not excluded if they otherwise meet the study inclusion criteria.Participants are evaluated at the University of Washington Virology Research Clinic. This trial was approved by the Fred Hutchinson Cancer Research Center institutional review board and registered at ClinicalTrials.gov , participants return for follow-up evaluation, blood draw, and optional oral sample. At study months 18 and 36, anal or vulvar swabs are obtained, and HRA or vulvoscopy is performed as surveillance for HSIL recurrence. If a lesion suspicious for HSIL is identified during the month 18 visit, a biopsy is taken. All participants receive a biopsy of any visible suspicious lesion at month 36, or at the site of the qualifying lesion if no lesion is identified. If HSIL is identified, the participants are asked to follow up with their health care clinician. Those who have a recurrence identified continue on the protocol to complete data collection for a secondary end point.Telephone interviews are conducted at months 12, 24, and 42; they include questions about general health and anogenital pathology. Pathology and treatment information for any anogenital biopsies conducted outside the study are retrieved and abstracted for the study .37 designed to be balanced by the following strata, in order of importance: anatomic site of lesion (vulva or anus), HIV status (positive or negative), and time since HSIL diagnosis (<1 year or ≥1 year) . Both participants and study staff involved in evaluation of participants are blinded to vaccine or placebo allocation.Enrolled participants are assigned at random to the 9vHPV vaccine group or the placebo group in a 1:1 ratio on the day of study enrollment. We conduct dynamic randomization≥1 year) . In brieThe sample size was determined by assuming 30% incidence of HSIL recurrence over 36 months among unvaccinated participants. We also assumed that vaccination with 9vHPV vaccine reduces the hazard of recurrence by 50%, for a cumulative incidence rate of 16% over 36 months among those who receive the active vaccine. Approximately 310 participants are needed to achieve 80% power given 1:1 randomization to vaccine and placebo. In prior studies conducted by our group, the loss to follow-up over 1 year is less than 3%. Because this study involves 36 months of follow-up, we will enroll 345 participants to allow for approximately 10% loss to follow-up.38 Other violations, such as failure to complete all vaccine doses, will be handled by comparison of the intention-to-treat (ITT) and per-protocol (PP) analyses.We anticipate some participants will miss visits, which adds uncertainty to the timing of events. For those who have a recurrence detected following 1 or more missed visits, a sensitivity analysis will be performed setting the timing of the recurrence first to its detection date and second to the date of the missed visit prior to detection. Similar to interval-censored methods, and in the setting of moderately stable hazards, we expect that exact timing is not critical to determine a difference in hazard of event by group.The ITT population will be all participants who have been randomized and received a dose of the vaccine. The PP population will be those who received 3 doses of the vaccine and did not have a subsequent HSIL within 1 month of the last dose. These persons in the PP population will also be required to have an HPV DNA type detected in the qualifying lesion that corresponds to HPV types included in the vaccine. Efficacy analyses will be conducted on both the ITT and PP populations.40 As this is a randomized trial, the primary analysis will include no other potential predictors of recurrence except for the treatment group: vaccine vs placebo. However, additional known risk factors will be included in secondary analyses of the primary aim, to confirm findings and to adjust for potential imbalances during randomization.We will evaluate differences in the hazard of recurrence using Cox proportional hazards in the ITT population and the PP population if the assumption of proportional hazards is not violated; otherwise, we will use log-rank methods for crossing hazards.42 We will also assess balance with regard to smoking status and include it in secondary models. We will assess whether to include time-varying smoking as a binary covariate using current consumption levels among smokers. Graphical depictions of end point rates by levels of smoking can help determine appropriate parameterization.In secondary analyses, we will adjust for the stratification factors of anatomic site, HIV status, and time since diagnosis of the qualifying lesion, as their inclusion may increase power.We will evaluate whether HSIL recurrence is more frequent among those with HPV persistence, defined as the detection of the same HPV DNA type or sequence variant in swab samples collected at months 0, 18, and 36. A Cox proportional hazards approach will include a time-dependent covariate for HPV persistence. Here, we will include vaccination status in the model and include HPV persistence as both a main effect and an interaction term. This will allow us to determine whether the presence of HPV genotype or HPV-16 sequence variant impacts the risk of HSIL recurrence differently depending on vaccination receipt.We will assess whether presence and amount of HPV antibody, detected at baseline in the placebo group, is protective against HSIL recurrence, separately among vaccine and placebo recipients. Subsequent graphical analysis examining incidence of recurrence by quartiles and deciles of antibody level will allow visual assessment of the relationship between levels of antibody and risk of recurrence. In further exploratory analyses, for the vaccine group, we will assess whether magnitude of vaccine-induced antibody levels a month following the third vaccination in the vaccine group is higher among those with detectable natural antibody at month 0 vs those without and whether prior antibody additionally reduces risk of recurrence. Should a threshold be observed, we may be able to determine the level of antibody associated with protection.We will compare the frequency of HSIL recurrence among those vaccinated vs those who received the placebo during follow-up for up to 36 months. In contrast to other aims, this analysis will include all recurrences, not just first recurrences. Thus, the time following first recurrence (primary end point) will be included as time at risk for additional recurrences. We will use Poisson regression with a robust variance estimate, comparing the total number of recurrences in each group with the total follow-up per group. This analysis is included in part to mitigate the potential influence of early recurrences, which may occur prior to the full benefit of the vaccine being achieved.The VIVA trial will address the proof-of-concept question for the therapeutic use of the 9vHPV vaccine among persons with HPV-associated anal or vulvar HSIL. If successful, this trial could lead to changes in the management of HSIL. The administration of the licensed HPV vaccine would be a low-cost adjunctive treatment for anal and vulvar HSIL that may reduce the frequency of surveillance and retreatment. Trial results may also clarify the role of natural antibodies in patients with recurrent HSIL.30 For example, in a pooled analysis28 of findings from the 4vHPV vaccine licensure trials, 587 4vHPV vaccine and 763 placebo recipients who underwent surgical treatment of squamous intraepithelial neoplasia of the cervix had 50% reduction  in recurrence of cervical disease among vaccinated women. In a retrospective study30 of 88 men with anal HSIL, those who received the 4vHPV vaccine after treatment had a 50% reduction of HSIL recurrence compared with unvaccinated men. Another retrospective study21 of 65 women with VIN3 examined the recurrence of vulvar HSIL and found that women who mounted natural antibodies to HPV-16 had a 30% decreased risk of recurrent lesions. These nonrandomized studies suggest that the immune response after natural infection and 4vHPV vaccination reduce the risk of HSIL recurrence. In contrast, a randomized trial43 conducted to assess whether 4vHPV vaccine prevents new HPV infections or decreases anal HSIL recurrence that enrolled 472 HIV-infected men and 103 HIV-infected women in the United States was stopped early for futility. After a median follow-up of 3.4 years, vaccine efficacy was 22%  for prevention of persistent infection. That study also failed to find evidence supporting an adjunctive role for HPV vaccination to improve outcomes following treatment of anal HSIL. Early study termination and lower than expected anal HPV infection affected the study’s ability to show efficacy.Observational studies suggest that the HPV vaccine may provide a partial therapeutic effect in already infected patients.NCT01928225) among 180 HIV-infected women followed up for 1 year; the relatively short follow-up duration and lower recurrence of cervical HSIL after treatment may limit the number of events detected. Another randomized trial (NCT02087384) in the Netherlands will assess the cumulative recurrence of anal lesions among HIV-infected MSM receiving the 4vHPV vaccine. Unlike the VIVA trial, these complementary trials are conducted exclusively in HIV-infected persons. Our target population is primarily identified from a population-based cancer registry and includes HIV-negative and HIV-positive persons with anal or vulvar HSIL.Additional clinical trials to address the use of the HPV vaccine among infected persons are ongoing. In South Africa, a randomized trial will assess the impact of the 4vHPV vaccine against recurrence of cervical HSIL , and dysplasia progression may vary between these groups. Additional studies may be necessary to determine vaccine efficacy between individual strata. Because the ultimate goal in the treatment of HSIL is to prevent the development of invasive cancer, the direct effect of the 9vHPV vaccine on cancer incidence will not be evaluated. However, we have defined a target population with sufficiently high recurrence burden to definitively assess the primary end point, which is an accepted surrogate for anal and vulvar cancer. Additional pragmatic trials may be needed to evaluate vaccine timing and implementation as an adjuvant therapy in clinical practice, particularly in low-resource areas. Integration of vaccine implementation will face several obstacles, especially in finding and treating patients who are treated for HSIL. Currently, there is a lack of screening and treatment guidelines for patients with noncervical HSIL disease, and health professionals need to be trained to appropriately evaluate these patients.47 Recurrences have been associated with decreased quality of life and significant morbidity due to disfiguring tissue removal and loss of function.48 In addition, follow-up and treatment of HSIL can be anxiety provoking and expensive. We estimated the potential cost of this intervention based on preliminary data assumptions and current vaccine cost: anal and vulvar recurrence rate of 30%, reduction of recurrences of 50% in vaccinated persons, and vaccine series cost of $375. The number needed to treat is 6.7; thus, anal or vulvar HSIL recurrence can be prevented for $2513. If this therapeutic approach is proven successful, immunization with 9vHPV vaccine may be a cost-effective approach to reducing the burden of recurrent HPV-related lesions.Secondary prevention of HPV-related anal and vulvar HSIL following treatment represents a medical need, particularly for at-risk populations such as MSM, HIV-infected persons, and solid-organ transplant recipients.We designed this clinical trial to evaluate the ability of a highly effective and safe prophylactic HPV vaccine in the prevention of secondary anal and vulvar HSIL. The study targets adults aged 27 to 69 years with a relatively uncommon precancerous lesion but with high rates of recurrence after primary treatment. Trial findings have the potential to provide critical knowledge in the possible use of the 9vHPV vaccine as an adjuvant therapy to current treatment regimens for vulvar and anal HSIL. If this study finds that this low-cost intervention is safe and successful, further research could be extended to other anatomical sites and populations in addition to evaluating the duration of protection against recurrent HSIL.


Odontogenic keratocysts (OKCs) are developmental odontogenic cysts affecting the maxillofacial region and their association with a syndrome especially Naevoid basal cell carcinoma syndrome (NBCCS) is a common occurrence in comparison to non syndromic multiple OKCs. In a first, we present a series of four non syndromic cases with multiple OKCs in western Indian population. The presence of multiple OKC in our present case series may be because of the multifocal nature of the lesion rather than its association with any syndrome. Thus, a comprehensive evaluation of any patients reporting with multiple cysts/OKCs always has to be undertaken and the dental practitioner may be the play a key role in early detection and subsequent follow-up. Key words:Abnormalities, multiple; basal cell nevus syndrome, India, odontogenic cysts. The authors have also stated that ‘further research is needed, but at the present time there appears to be insufficient evidence to support a neoplastic origin of OKC. It was therefore felt that OKC remains the most appropriate name for this lesion’ (Odontogenic Keratocysts (OKC) has been in past synonymously known as primordial cysts, keratocystic odontogenic tumour (KCOT)  is an odOKCs account for 10-20% of odontogenic cysts and are the third most common cyst of the jaws , Ehler-Det al., noted that only 23 cases of NBCCS have been reported in Indian patients, it is evident that the frequency of clinical and radiological features in NBCCS in Indian patients differs from other ethnic groups. Either NBCCS is rare in the Indian population or may be under-reported owing to lack of awareness about the clinical and radiological manifestations of NBCCS. The absence of family history and other features of the syndrome can be due to variation in penetration and expression of different mutations within the Patched (PTCH) gene or the effects of modifier genes and environmental factors in different ethnic groups , Computed tomography (CT) and radiological evaluation of skull bones, chest, hands, feet, long bones, pelvis, and spine were carried out for all patients. The patients were referred to dermatology , neurology , ophthalmology , cardiology, surgery and ear, nose, and throat departments for a multisystem evaluation. The processing and histopathological examination of the biopsy specimen was done in the Department of Oral Pathology.-Case 1A 15 year old male patient with a history of swelling in right and left back region of mouth since last 18 months visited the OPD. Intra-oral examination showed approximately 3 x 2.5 cm swelling in the right lower side and 3 x 3 cm swelling in the left lower side. Patient was not aware of any maxillary lesions as the radiographical examinations revealed multiple radiolucent (05) lesions: i) multilocular radiolucent lesion distal to roots of 46 up to ramus involving impacted 48, ii) multilocular radiolucent lesion distal to roots of 37 upto ramus involving impacted 38, iii) unilocular radiolucent lesion distal to roots of 17, iv) unilocular radiolucent between displaced roots of 22, 23, v) unilocular radiolucent lesion distal to roots of 27  radiolucent lesions: i) multilocular radiolucency in the mandibular angle with scalloped margins in 44, 45, 46 & 48 region, root resorption of 44, 45, 46 & 48 seen and missing 47. ii) unilocular radiolucency extending from 42 to 38 with impacted 33 and missing 41, 35, 36 and transposed tooth 34 along with root resorption. iii) unilocular radiolucency in left mandibular ramus, iv) multilocular radiolucency along roots of 21 to 27 / calcifying odontogenic cyst (COC) and persisted in the time-honored terms of OKC and COC as the editors felt that most cases of KCOT and CCOT behave clinically as non-neoplastic lesions and are treated as cysts (The multifocal nature of OKC may the source of occurrence of multiple cysts as discussed by Boyne in their study of resected mandibular specimens with OKCs . This pa


We performed the analysis along environmental and ecological gradients of pine forests in Southern Europe. Models suggested that, naturalization strategies, in this case defined by the replacement of planted pine forests and eucalyptus forests by natural pine forests, could help to mitigate the expected loss of bird diversity due to climate change, but that mitigation efficiency will vary along environmental and ecological gradients. Maximum levels of diversity mitigation were predicted at intermediate levels of naturalization, with lower bird richness in areas where all pine forests were either planted or naturalized. Efficiency also varied spatially, given that both cold- and hot-spots of climate-driven bird diversity loss were identified. Transforming planted forest into natural forest is not a mitigation panacea, and additional regionally-adapted strategies may be identified to mitigate the expected biodiversity loss in forest ecosystems.There are many possible strategies to promote naturalization in anthropogenic landscapes to mitigate global change effects. We combined large-scale databases available for continental Spain on: (1) distribution of breeding birds, (2) forest inventory stands, (3) land-use cover, (4) 18 global climate models recently developed at local scales, and (5) historical and genetically-based information on the distribution of natural  Climate change is a serious threat to the well-being of humans, and it is considered one of the greatest challenges currently being faced by the world. Climate change is eroding the natural resources and the biodiversity of ecological systems, which will lead to unprecedented consequences unless ambitious mitigation policies are implemented ,2. SpeciHow forests and tree plantations should be managed to make them more complex and thus preserve biodiversity has been largely debated ,12, mainWe explore how bird diversity would change during the process of forest naturalization in continental Spain, a region located in a Mediterranean hotspot  where clMediterranean ecosystems are expected to be impacted by climate change due to their position at the trailing edge of species distributions ) and to ® software by Esri. The sources used to collect the data were diverse: (1) digital elevation models to calculate orographic variables (25x25 m); (2) the Third Spanish Forest Inventory to characterize forest composition and structure  UTM-grid .Pinus spp. occupied more than 50% of the cell using the Spanish Forest Map , as well as on the information of bird habitat requirements compiled in the bird atlas  into pine forests, assuming that such exotic plantations do not provide adequate habitat for native birds [The naturalization of forests within the context of this study is defined as a two-step management action. First, current pine plantations, defined as such on the basis of the well-known genetic and historical regions of provenance of pine forests , were cove birds .et al. [Pinus spp. by taking into account additional interactions between plantation origin, geographical coordinates, and climate variables. All variables used in the model to explain bird diversity were previously inspected to determine linear or curvilinear relationships with respect to the explanatory variable using generalized additive models (“mgcv” library in R 3.3.1), fitting a second-order polynomial transformation when necessary  and different naturalization efforts . We added a further set of scenarios where the entire surface area occupied by vs planted pine forest, as well as some interactions between the origin of the forest, geographical coordinates and climatic conditions are important to explain the distribution of bird diversity in the Iberian Peninsula . Further, the efficiency of naturalization would be highly heterogeneous spatially, with well-delimited regions where winners and losers can be identified. Fortunately, local losses would not imply regional extinctions, given that bird distributions will likely expand northwards as bioclimatic conditions change towards conditions now typical from the southwestern Mediterranean region ,43. StraTherefore, naturalization strategies are useful for mitigating biodiversity loss under climate change scenarios, although non-linear effectiveness and spatial variability should be taken into account before applying such strategies at regional scales. Our analysis was focused on overall pine forest dwelling bird biodiversity rather than considering focal species, and therefore we did not account for the likely roles played by species-specific responses to climate change in terms of demography, dispersal, contemporary evolution, or species interactions . NaturalS1 TableTotal number of 10x10-km UTM grids with presence of Pinus spp and the percentage of pine plantations and natural forest occupied by each species are also shown.(DOCX)Click here for additional data file.


Cell surface carbohydrates (known as glycans) are often aberrantly expressed or found at atypical levels in cancer. Glycans can impact all steps in tumour progression, from malignant transformation to metastasis, and have roles in all the cancer hallmarks. An increased understanding of glycans in the metastatic cascade offers exciting new therapeutic opportunities. Glycan-based targeting strategies are currently being tested in clinical trials and are a rich and untapped frontier for development. As we learn more about cancer glycobiology, new targets will continue to emerge for drug design. One key change in tumour glycosylation is the upregulation of cancer-associated sialylated glycans. Abnormal sialylation is integral to tumour growth, metastasis and immune evasion; therefore, targeting sialic acid moieties in cancer could be of high therapeutic value. Here, we summarise the changes to sialic acid biology in cancer and discuss recent advances and technologies bringing sialic-acid targeting treatments to the forefront of cancer therapeutics. All cells are coated with carbohydrates, known as glycans, which form a layer on the cell surface known as the glycocalyx . GlycansOne key change in tumour glycosylation is the upregulation of cancer-associated sialylated glycans, known as tumour sialoglycans . Sialic Aberrant sialylation contributes to tumour growth and metastasis at multiple levels and has been described as a key player in cancer progression ,12,13. S53FaxNeu5Ac can block sialic acid expression and suppress tumour growth in multiple in vivo tumour models [New tools to target sialic acids are being developed and have shown promise in preventing/inhibiting cancer metastasis. The sialic acid glycomimetic (P-3Fax-Neu5Ac) delays tumour growth in vivo and can be delivered to cancer cells using nanoparticles to prevent the metastatic spread of melanoma cells to the lung in a murine model ,26. Intrr models . These fThe tumour glyco-code is generated through the cooperative action of multiple glycosylation enzymes that catalyse the addition or removal of specific glycans onto proteins and lipids. These changes are often driven by the altered expression of genes involved in glycan synthesis . AbnormaX) in gastric carcinoma [X and the generation of E-selectin ligands [Key examples of sialyltransferases important in cancer include ST6GAL1; ST3GAL4 ST3GAL6 and ST6GalNAc1/2 , an increase in the truncated O-glycan sialyl-Tn (STn) and an increase in the sialylated ganglioside GM2 [A and sLex are recognised as migrating leucocytes, enabling them to escape the bloodstream and colonise other organs and tissues [A and sLeX, and thus targeting selectins and sLeA/X is attractive therapeutically [Changes to sialylated glycans in cancer include an upregulation of the Sialyl Lewis antigens  are important regulators of cell signalling in cancer . The comThe aberrant glycosylation of tumour cells can lead to new connections with immune cells resulting in an immunosuppressive phenotype. This can be through the induction of self-glycan structures to limit immune self-reactive responses or by the expression of glycans that can reduce the function of effector T cells . The denTargeting sialic acid moieties has become an upcoming strategy for cancer immunotherapy ,52. StudPrecision glycocalyx editing with antibody-sialidase conjugates has also been reported and is a promising avenue for cancer immune therapy. Here, an antibody directs sialidase to selectively remove sialic acid from tumour cells and enable immune cells to kill the desialylated cancer cells . The EAGIn the era of personalised medicine, there is a huge potential to develop new glycan-based therapies to treat cancer. A key change in cancer glycosylation is an upregulation in the levels of sialylation, as well as the expression of cancer-associated sialoglycans. Aberrant sialylation is integral to tumour growth, survival, metastasis and immune evasion, and targeting abnormal sialylation will likely be of high therapeutic value. New technologies to study glycosylation are bringing glycan targeting strategies to the forefront of cancer therapeutics, particularly in the area of cancer immunology. Moving forward, drugs targeting tumour glycans will likely be used synergistically with existing chemotherapy and/or radiotherapy approaches to impact disease outcomes. As well as themselves being drug targets, changes to glycans can likely also be exploited to predict sensitivity and resistance to other treatment strategies and, ultimately, improve clinical outcome.


Modern birds  are toothless; however, the extinct neornithine Odontopterygiformes possessed bone excrescences (pseudoteeth) which resembled teeth, distributed sequentially by size along jaws. The origin of pseudoteeth is enigmatic, but based on recent evidence, including microanatomical and histological analyses, we propose that conserved odontogenetic pathways most probably regulated the development of pseudodentition. The delayed pseudoteeth growth and epithelium keratinization allowed for the existence of a temporal window during which competent osteoblasts could respond to oral epithelial signaling, in place of the no longer present odontoblasts; thus, bony pseudoteeth developed instead of true teeth. Dynamic morphogenetic fields can explain the particular, sequential size distribution of pseudoteeth along the jaws of these birds. Hence, this appears as a new kind of deep homology, by which ancient odontogenetic developmental processes would have controlled the evolution of pseudodentition, structurally different from a true dentition, but morphologically and functionally similar. However, members of an extinct Neornithine clade known from almost 60 Ma to ca. 2.5 Ma, the order Odontopterygiformes, large pelagic birds, grew a series of pseudoteeth along their jaw tomia, the cores of which were made of bone5 , and are not inserted in alveoli (sockets) -or grooves. Moreover, the occurrence of numerous neurovascular foramina openings at the surface of the pseudoteeth bony cores , location on jaw tomia, and regular, serial (meristic) distribution. In addition, pseudodentition is characterized by a very peculiar, serial distribution of the pseudoteeth  with documented jaw elements indicate that tooth loss occurred between 125 and 66 million years ago (Ma)5, as well as new, original lines of evidence, we propose an integrative developmental model which suggests that a diverted odontogenetic potential was probably active  in the developmental control of pseudodentition .Until now, the evolutionary and developmental origins of pseudoteeth have been challenging. Nevertheless, by considering the unique characteristics of the pseudodentition, the growth pattern of individual pseudoteeth in one speciesPelagornis mauretanicus indicate that their growth on the jaw tomia started during, or shortly after, completion of the circumferential  growth of the supporting jaw bones 5 . Such a late pseudotooth growth would have been associated with delayed keratinization of the overlying epithelial layers long after hatching5 and just prior to independence from the parents, presumably approaching 18 months after hatching in large pseudotoothed bird species (SText 4). Therefore, until this late keratinization, the whole epithelium would have remained alive and continued odontogenetic signaling until late development. In contrast, early epithelium keratinization  implies the death of epithelial cells across most of the epithelial depth, rendering interaction with the underlying mesenchyme impossible. Such delayed rhamphothecal keratinization might be paralleled by the existence of a soft rhamphotheca, at least locally, in adult representatives of three extant bird taxa: Anseriformes, Apterygidae and some Charadriidae, lineages that have been toothless for a long time5. In the hypothesis of a sister relationship between the orders Odontopterygiformes and Anseriformes (superorder Odontoanserae)12, a shared phylogenetic background might have favoured the effects of a mutation which caused delayed epithelial keratinization in pseudotoothed birds. Late epithelial keratinization would be viable for young birds if the latter did not use their fragile, acute, growing pseudoteeth with soft epithelium, but were fed by adults during a prolonged period, at least until the end of pseudodentition growth and full rhamphothecal keratinization5.The micro-anatomical and histological characteristics of pseudotooth bony cores in the odontopterygiform 14; however, altriciality in Odontopterygiformes − be it sister to the Neognathae, the Galloanserae or the Anseriformes − would have been the most basally derived altriciality, given that all basal Neornithes  are precocial to superprecocial14. Delayed epithelial keratinization, a condition of prolonged epithelial signaling in pseudotoothed birds, would have been a non-counter-selected by-product of their derived altriciality.Comparable altriciality is a derived condition in several lineages15 the osteoblasts of the jaw bone periosteum did respond; enabling oral epithelium-osteoblast interactions to ensue, which induced the differentiation, growth, and shaping of the pseudoteeth. This scenario raises two issues: (i) the effective continuation of epithelial signaling, and (ii) the possibility for periosteal osteoblasts to interact with the signaling basal epithelial cells.In addition to this potential role for prolonged epithelial signaling, the exclusive location of pseudoteeth on the tomial edges of the jaws, their individualization, and regular spacing that constituted a serial meristic trait, and, to a lesser extent, their simple, almost conical tooth-like shape, suggest that some developmental bases were shared with typical odontogenesis . We propose that, near the end of the circumferential growth of supporting jaw bones, delayed oral epithelial keratinization allowed basal epithelial cells to continue expressing odontogenetic signaling molecules, to which competent ectomesenchymal cells, such as in extant toothed vertebrates, would have been able to respond. Additionally, we postulate that in the absence of such odontogenetic ectomesenchymal competent cells – a situation which occurs in extant birdsBMP4 by the oral epithelium is a good candidate16, (ii) lack of competent ectomesenchymal cells which normally migrate from the neural crests into the oral mesenchyme and differentiate into odontoblasts17, (iii) lateral shift of the boundary between the epithelium and the mesenchyme15, (iv) diversion of gene function toward the formation of a rhamphotheca and subsequent impossibility for the keratinized epithelium to interact with the mesenchyme2 these possible causes are not mutually exclusive2. Nevertheless, the earliest steps of odontogenesis still occur in the chick embryo but the sequence of development stops at embryonic day E5, before the tooth bud stage has been reached. In the talpid2 (ta2) mutant chicken embryo, dental development continues further with the production of tooth rudiments; however, as this mutation is lethal, this development cannot continue later than E1715. These data indicate that odontogenetic epithelial signaling is maintained and can be reactivated in the chicken upon interaction with competent odontoblasts to form tooth rudiments, as demonstrated by using experimental recombination of chick oral epithelial cells and mouse neural crest-derived cells17. We postulate that, in the earliest derived toothless odontopterygiforms 17. Indeed, if these cells had been present, pseudoteeth would have displayed most of the characteristics of true teeth − such as a dentin-like tissue surrounding a pulp cavity and other features − which is not the case. The only alternative hypothesis is that osteoblasts from the jaw periosteum facing the oral epithelium did respond to signaling molecules expressed by the basal oral epithelial cells. This means that periosteal osteoblasts were competent to start such an interaction, and continued until the formation of odontoid excrescences. Indeed, osteoblasts are known to have close evolutionary relationships with odontoblasts20. Osteoblasts − cells of mesenchymal origin − have strong developmental affinities with odontoblasts of ectomesenchymal origin, as evidenced by numerous examples of toothed vertebrates blurring the limit between bone and dentine with a histological continuum19. Alveolar bone first appeared at least in basal amniotes21, being identified in a close relative of the last common ancestor of mammals and sauropsids. Hence, both alveolar bone and dentin were present in the Ichthyornithiformes and the Hesperornithiformes, which are the nearest toothed relatives of the Neornithes22, and pseudotoothed birds. Both alveolar bone and dentin arise from the same cell population that differentiates into odontoblasts and osteoblasts, respectively; a differentiation process regulated by various genes including Runx220. Therefore, we postulate that the periosteal osteoblasts that formed pseudoteeth were capable of responding, with their own potential, to oral epithelial cell signaling.The possible causes of the loss of capability to form teeth in the neornithine basal lineage are as follows: (i) absence of odontogenetic gene expression, among which the expression of 24.Another necessary condition for pseudotooth formation in Odontopterygiformes (see SText 6) is that the oral epithelium signaling, and its subsequent interactions with the mesenchyme, continued sufficiently late during ontogeny, ending only when the delayed keratinization of the basal epithelial cells occurred. Indeed, during this period, the jaw bones increased in circumference, which allowed periosteal osteoblasts to interact with the basal epithelial cells due to their close proximity. This necessary time window was made possible relatively late in ontogeny, but nevertheless early enough thanks to prolonged oral epithelium signaling. Based on the known distance of diffusion of the oral epithelial odontogenetic signaling through the mesenchyme in extant toothed taxa, the optimal distance favouring interactions between the basal epithelial cells and the periosteum should be as small as a few tens of micrometers (max. ~100 µm)25. Osteoblasts proliferated as meristically individualized populations developing at regularly spaced intervals along the tomial surface of the jaw bones 26. It is noteworthy that the “ameloblasts”, although controlling the pseudotooth shape, were unable to deposit enamel matrix proteins on the bone surface. Indeed, all the specific genes encoding these proteins were already invalidated in the earliest Odontopterygiformes, about 50 myrs after the common ancestor of modern birds lost the capability to develop teeth – as they are invalidated in extant birds28.Once periosteal osteoblasts had responded to the signaling molecules secreted by the basal cells of the oral epithelium, the genetical cascade controlling epithelial-mesenchymal interactions was initiated, as for normal odontogenesisnes Figs  and 4. Ones Figs  and 4. TThe growth of pseudodentition ended after it expressed its unique, alternate distribution of unequally-sized pseudoteeth. The setting of this particular and regular size distributional pattern implies further characterization of our model.31, the setting up of a serial distribution of the invaginations, where interaction developed, was presumably induced by equally dimensioned and equally-spaced inhibition zones. These morphogenetic fields inhibited the development of another pseudotooth within the radius of a sphere-like zone of influence  are situated between PT3s and PT2s and between PT3s and PT1s -(4)-(5)-3-(5)-(4)-(5)-2-(5)-(4)-(5)-3-(5)-(4)-(5)-1  of the invaginating basal epithelial layer. These putatively sphere-like zones of inhibition prevented the development of adjacent pseudoteeth within their field of influence. While the first series of pseudoteeth were developing (future PT1s), their respective inhibition zones were progressively decreasing in radius. As a consequence, spaces became free from inhibition at locations equidistant from two consecutive PT1s. The PT2 series could then start developing through epithelial-osteoblast interactions, which in turn produced their own smaller inhibition zone  (SText Most differences in the size distribution of pseudoteeth across various odontopterygiform species (or unnamed specimens) can be interpreted in terms of the species-specific characteristics of inhibition zones, and their modifications during development . Nevertheless, a consistent correlation emerges and adds support to our model. In species with a larger interval between PT1s , the PT3s show an attenuated size decrease relative to PT2s, compared with the size decrease of PT2s vs PT1s (SText 8). This is what would be expected if the inhibitory action of the larger pseudoteeth actually delayed the growth of the last emerging  pseudoteeth − the latter reaching a size limited by the duration of inhibition by the larger pseudoteeth through pseudodentition growth. This duration of inhibition, in our model, is greater with larger PT1s and/or with a smaller interval between them. Another characteristic, common to all taxa, is that the lower-ranked pseudoteeth are increasingly more constricted rostro-caudally. This strongly suggests that increasingly constraining inhibition zones during the development of the lower-ranked pseudoteeth, with a smaller intervening space, imposed narrower spaces for rostro-caudal development. This can be clearly seen in the t) SText ; SFig. 4Pristiophorus; SFigs Pristiophorus (though not during its subsequent tooth replacements)38. In the longnose sawshark, P. cirratus, the largest teeth grow first, followed by the medium-sized ones, and finally the smaller ones39, which is similar to the growth sequence considered in our model for pseudodentition. These observations add further support to our hypothesis, since they attest to a possible common underlying mechanism operating on true teeth as well as on pseudoteeth.The particular sequential size distribution of pseudoteeth is paralleled by that of teeth in the dentition of several fish lineages  between chick embryo oral epithelial and mesenchymal tissues.Pseudoteeth differ from true teeth, not only in the tissues involved (bone and keratinizing epithelium vs dentin and enamel) and the lack of pulp cavity, but also in their growth and mineralization dynamics, and in relation to the jaw bone. In true teeth, dental tissues develop and mineralize centripetally before attachment to the jaw bone, and once their final shape is achieved the covering tissue deposited by the ameloblasts (enamel) is highly mineralized prior to eruption. In contrast, the bony cores of pseudoteeth were already part of the jaw bone, and they developed and mineralized centrifugally, through a combined process of external accretion and internal resorption of the cortex. The epithelium covering the bony cores of the pseudoteeth became hardened by means of keratinization (like the rest of the rhamphotheca) after ‘eruption’ (emergence) and completed growth. Therefore, in the model we propose, the only common process when comparing pseudotooth and true tooth formation consists of the epithelial-mesenchymal interactions modeling the final shape, and the capability of osteoblasts to respond to epithelial signaling, as odontoblasts do for teeth. This behaviour is made possible by (i) the common evolutionary origin of osteoblasts and odontoblasts, and (ii) the close vicinity of the interacting cells, osteoblasts, and basal layer epithelial cells. This genetic cascade regulates relatively simple shape, differential growth, and seriality along the tomia. Such an opportunistic diversion of available epithelial odontogenetic signaling making the regulation of bone growth possible is unique among vertebrates. This attests to the considerable plasticity of a developmental program, which is capable in forming highly derived structures similar to dentition, despite the loss of ability to develop true teeth, in crown group birds. As such, this evolutionary innovation not only produced organs that were functionally convergent with dentitions, but is also a new illustration of a kind of deep homology43. This conformation weakened grasping strength43 and, in the absence of teeth in odontopterygiforms, pseudodentition could have acted as a counterbalancing grasping enhancer. The conformation of the mandible would have evolved in co-adaptation with the pseudodentition. This evolutionary resourcefulness produced structures possibly less resistant than teeth44. Nevertheless, pseudotoothed birds were extremely successful, wandering the world’s oceans for more than 55 million years7.Once the process of pseudodentition growth was acquired by an ancestral odontopterygiform, it was maintained in derived lineages presumably for adaptive reasons . Among Ornithurae, the combination of streptognathism and absence of mandibular symphysis only occurs in the Odontopterygiformes and the Cretaceous toothed avian taxa Ichthyornithiformes and Hesperornithiformes, the respective sister taxa of crown group birdsDasornis 6 and Pelagornis 5 were examined for comparison, as well as specimens of Hesperornis regalis 22. The Dasornis and Pelagornis fossils were imaged using conventional X-ray microtomography, performed at the Ecole Normale Supérieure de Lyon and at General Electrics (Lyon) using Phoenix Nanotom. The Hesperornis fossil was imaged using synchrotron X-ray microtomography at the European Synchrotron Radiation Facility (Grenoble). The 3D volumes obtained were analyzed using VGStudio MAX 2, as previously described22.Specimens of Supplementary Information


Insofar, a biomarker axis may provide a higher accuracy in the diagnosis of the disorder with benefits for prediction in PTSD treatment response and relapse  and major depressive disorder , major depression, PTSD, perceived social isolation, post-partum depression, premenstrual syndrome, and anorexia nervosa or obesity complicated by anxiety and depression symptoms in women , stimulation of neurotropic factors , and/or crosstalk with the endocannabinoid system  may provide a valuable biomarker axis with a higher disorder-selectivity. This analysis includes both neurosteroids that are positive allosteric modulators of GABAA receptors  that act as potent positive allosteric modulators of the action of GABA at GABAA receptors. One is located at the interface of the α/β subunits, and the other is within the cavity of α subunits , the role and action of sulfated pregnanolone, pregnenolone, allopregnanolone, and the expression of NMDA receptor subunits in PTSD patients and in rodent stress models, still warrants elucidation.Sulfated or unconjugated neuroactive steroids modulate ionotropic amino acid neurotransmitter receptors, including GABAbiomarker axis uniquely altered in specific stress-induced mood disorders.Intriguingly, studies conducted in cell cultures, brainstem and spinal cord showed the endocannabinoid, PEA binding at the ligand-activated nuclear receptor, PPAR-α stimulates allopregnanolone biosynthesis and potentiates pentobarbital-induced sedation . If successfully developed, SAGE-217 will be the first durable, rapid-acting, oral, short-course treatment for mood disorders with potential application for PTSD treatment. Stress tremendously affects the expression of GABAA receptor subunits  downregulated neurosteroidogenesis; and (iii) lack of response to benzodiazepines, which may provide a unique biomarker axis for PTSD  assessing novel biomarkers to predict, diagnose, and treat PTSD at the interface of the PPAR-α-allopregnanolone axis; and (ii) repurposing FDA-approved PPAR-α agonists for the treatment of PTSD after positive clinical trials. Very few drugs are direct agonists of PPAR-α, and none have been tested for their potential effects in fear responses. However, one class of drugs, the fibrates are fibric acid derivatives that are prescribed to lower plasma lipids and triglyceride levels and are synthetic PPAR-α agonists that may be exploited in rodent models of PTSD to improve behavioral deficits.Progress in assessing biomarkers to predict PTSD and its treatment response will guide the future of novel PTSD medications that may be designed to improve neurotransmission , and neuroendocrinologic  and anti-inflammatory (PPAR-α) responses. Research supports precision medicine for PTSD designed to stimulate neurosteroidogenesis after assessing in subpopulations of PTSD patients a downregulation of allopregnanolone biosynthesis. This can be achieved by acting at neurosteroidogenic targets or by mimicking allopregnanolone's function . Several neuronal targets to enhance steroidogenesis have recently been discovered and these include the endocannabinoid target PPAR-α. The crosstalk between the endocannabinoid system and the biosynthesis of neurosteroids, involving their targeted receptors or the biosynthetic enzymes promises to provide unique bio-signatures for stress-induced disorders.Collectively, advances in the field suggest biomarker-based diagnosis and treatments for PTSD that encompass the neurosteroid and endocannabinoid systems may not be a far reach and these may provide a pivotal complement to the current practice of assessing the disorder based on self-reported symptoms and psychiatrist assessments.The author confirms being the sole contributor of this work and approved it for publication.The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


This review contrasts the neuromodulatory influences of acetylcholine (ACh) on the relatively conserved primary visual cortex (V1), compared to the newly evolved dorsolateral prefrontal association cortex (dlPFC). ACh is critical both for proper circuit development and organization, and for optimal functioning of mature systems in both cortical regions. ACh acts through both nicotinic and muscarinic receptors, which show very different expression profiles in V1 vs. dlPFC, and differing effects on neuronal firing. Cholinergic effects mediate attentional influences in V1, enhancing representation of incoming sensory stimuli. In dlPFC ACh plays a permissive role for network communication. ACh receptor expression and ACh actions in higher visual areas have an intermediate profile between V1 and dlPFC. This changing role of ACh modulation across association cortices may help to illuminate the particular susceptibility of PFC in cognitive disorders, and provide therapeutic targets to strengthen cognition. Acetylcholine (ACh) plays many neuromodulatory roles in the developing and mature brain, including guiding neuronal development, determining arousal state, and modifying cortical responses to environmental events. This review will provide a brief summary of cholinergic anatomy and development, and contrast the roles of ACh in the mature primary visual cortex (V1) with those in visual association cortices, and in the newly evolved dorsolateral prefrontal cortex (dlPFC), the site of working memory circuits. Finally, we will discuss evidence for disruptions in normal cholinergic processing contributing to cognitive disorders, and how the organization and signaling mechanisms of dlPFC circuits may increase their sensitivity to cholinergic disruption.In primates, ACh is synthesized by neurons in eight primary nuclei in the brainstem and basal forebrain. Four of these nuclei in the brainstem and midbrain (Ch5-8) innervate the thalamus, dopaminergic nuclei in the midbrain, interpeduncular brain stem nuclei, superior colliculus, and are implicated in arousal and sleep Figure . The othEvidence suggests these cholinergic nuclei show significant differences between rodents and primates, most prominently in the specificity of afferent and efferent connections and in the proportions of GABAergic and other noncholinergic neurons to cholinergic cells  into inositol triphosphate (IP3) and diacetylglycerol (DAG), which release calcium from intracellular stores and activate PKC. The M2 and M4 receptors are coupled to Gαi/o, which inhibits adenylyl cyclase and reduces cAMP levels.ACh acts through both ionotropic nicotinic receptors and metabotropic muscarinic receptors expressed throughout the central nervous system. Nicotinic receptors are ion channels comprised of α (α2-α10) and β (β2-β4) subunits, forming a non-selective cation channel. Muscarinic receptors are metabotropic receptors, of which five functional subtypes have been identified, M1–M5. The M1, M3, and M5 receptors are coupled to GαThe cholinergic nuclei first appear and extend projections during embryonic stages of brain development, and may contribute to neural differentiation, migration, axon guidance, and local circuit formation and maturation across the cortex, as described in the following section.Studies examining receptor expression, ACh synthesis markers, alterations with genetic knock-down of receptor types, and physiological recordings all support a critical role for ACh throughout cortical and subcortical brain development to promote neuronal maturation, guide circuit formation, and refine synaptic connections.There is evidence from both rodents and humans that nicotinic and muscarinic receptors are expressed in early embryonic development in cortical stem cells and progenitor cells, as early as E10 in mice and during the first trimester (4–12 weeks) in human embryonic development , the enzyme which rapidly catalyzes the breakdown of ACh, is expressed in the developing primate brain during developmental windows where connections are being wired. During late embryonic development and the first few postnatal weeks in rhesus macaque development, AChE is transiently expressed in thalamic neuron axon terminals projecting to specific cortical areas, suggesting a potential contribution to guiding thalamic afferents to cortex    when a distracting stimulus is presented during the delay. This reduction in activity can be blocked by iontophoretic application of a nicotinic α4β2 receptor agonist  have found associations within the gene locus for the nicotinic α7 subunit , since the finding that basal forebrain nuclei degenerate in AD (Whitehouse et al., While there is still much we do not understand about the precise function of ACh and its receptors in development and mature brain processing, it is evident ACh plays a critical role in cortical development and in higher cortical processing. ACh signaling plays a key role in amplifying incoming sensory signals, and is critical for higher order cognitive processes, permitting critical activation of PFC circuits underlying working memory. It appears to be particularly important for providing neural excitation under conditions when there is no or little sensory stimulation, e.g., during development of the visual system prior to eye opening, or in mature dlPFC microcircuits that need to maintain representations of events in the absence of sensory stimulation. The differences in cholinergic actions across primary sensory to high order association cortices is correlated with strength of attentional modulation, is tailored to the different functions of each cortical area, and exerts influence via actions at nicotinic and muscarinic receptors which show highly different expression patterns across cortical regions. The heaviest cholinergic innervation of limbic cortical areas is reminiscent of the pattern of degeneration in neuropsychiatric diseases with altered ACh levels or receptor function. The differences in PFC and V1 for ACh function may be useful in guiding development of future therapeutics for such disorders, using low-dose therapies to improve PFC circuit function without altering other brain regions and systems.AA and VG contributed to formation of review topic. AA and MW supported and guided VG in writing of review.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.


Although many chaperones require constitutive self-interaction (dimerization and oligomerization) to function, Hsp70 has been thought to exist as a monomer, especially in eukaryotic cells. Recent studies have demonstrated that both bacterial and mammalian Hsp70 can exist as a dynamic pool of monomers, dimer, and oligomers. In this mini-review, we discuss the mechanisms and roles of Hsp70 oligomerization in Hsp70 function, as well as thoughts on how this integrates into well-established ideas of Hsp70 regulation.The Hsp70 molecular chaperone in conjunction with Hsp90 and a suite of helper co-chaperones are required for the folding and subsequent refolding of a large proportion of the proteome. These proteins are critical for cell viability and play major roles in diseases of proteostasis which include neurodegenerative diseases and cancer. As a consequence, a large scientific effort has gone into understanding how chaperones such as Hsp70 function at the  Saccharomyces cerevisiae possess a total of 11 Hsp70 paralogs; 4 semi-redundant cytosolic forms (Ssa1-4), 3 located in the mitochondria and 1 ER-specific form (Kar2) , a 44-KDa structure that is involved in the binding of Hsp70 and hydrolysis of ATP, a 28 kDa Substrate binding domain (SBD) that binds unfolded and misfolded clients, and a C-terminal region containing leucine rich EEVD motif, essential for client refolding. The NBD and SBD are connected via a flexible linker domain that transmits structural re-arrangements brought about by the hydrolysis of ATP to the SBD, allowing client folding  on Hsp70 that include acetylation, phosphorylation, ubiquitination, oxidation, and AMPylation  varied in both PTM content and monomer-dimer population  such as phosphorylation, acetylation, methylation, ubiquitination, and SUMOylation all play a role in the activity, and specificity of chaperones and co-chaperones  is controlled by BiP  produces BiP that is primarily monomeric with no evidence of oligomers, while BiP purified from bovine extracts exists as an array of monomers, dimers, trimers, and oligomers  or in human Hsp70  does not significantly impact the Co-chaperone proteins are critical for regulating the activity and specificity of Hsp70 (Kampinga and Craig, Few studies have analyzed the impact of Hsp70 dimer formation on client binding. Early work on Hsc70 demonstrated a capability to oligomerize during the removal of clathrin from coated vesicles during receptor-mediated endocytosis (Schmid and Rothman, Molecular chaperones play an important role in tumor initiation and progression (Goloudina et al., in vitro and in vivo (Mollapour et al., Growing evidence from numerous studies on Hsp70 suggests that dimerization and higher-state oligomerization have important functional implications, affecting interactions with co-chaperones and client binding complexes. In contrast to other chaperone proteins such as Hsp90 and Hsp40 whose constitutive dimerization is essential for their cellular function, Hsp70 self-association is clearly required for only a subset specific set of chaperone functions and is dispensable for cell viability. If a subset of Hsp70 needs to exist in a self-associated state, what then is the initiating signal that regulates the monomer to oligomer transition? It is clear that PTMs on can alter propensity for dimerization (Morgner et al., Although the research on Hsp70 oligomerization is in its infancy, oligomerization may serve several purposes in protein quality control. Hsp70 oligomers may function as storage oligomers, dissociating, and becoming active upon cellular stress. Although feasible, this would imply that the dimer and oligomer forms are completely inactive, which is clearly not the case. A more reasonable model is a chaperone assembly line, where cell stress alters the chaperone code, leading to oligomerization. This in turn would promote association of co-chaperones and client to allow client folding . This moThe sequence similarity between Hsp70 isoforms raises an interesting question: can Hsp70 isoforms heterodimerize and if so, what does this mean for functionality? A precedent already exists with yeast Ssa1 forming a heterodimer with the co-chaperone Sse1 (Shaner et al., JT, and N wrote the initial drafts of the manuscript. LK created 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.


While recent increases in our understanding of the biology of neuroblastoma have allowed for more precise risk stratification and improved outcomes for many patients, children with high-risk neuroblastoma continue to suffer from frequent disease relapse, and despite recent advances in our understanding of neuroblastoma pathogenesis, the outcomes for children with relapsed neuroblastoma remain poor. These children with relapsed neuroblastoma, therefore, continue to need novel treatment strategies based on a better understanding of neuroblastoma biology to improve outcomes. The discovery of new tumor targets and the development of novel antibody- and cell-mediated immunotherapy agents have led to a large number of clinical trials for children with relapsed neuroblastoma, and additional clinical trials using molecular and genetic tumor profiling to target tumor-specific aberrations are ongoing. Combinations of these new therapeutic modalities with current treatment regimens will likely be needed to improve the outcomes of children with relapsed and refractory neuroblastoma. With new treatment strategies, including immunotherapy and therapies directed against tumor-specific molecular aberrations, the outcomes of children with high-risk neuroblastoma have significantly improved over the past two decades. Despite these recent successes, however, many of these children continue to suffer from refractory or relapsed disease, and to date, there are no established curative treatment options for many of these patients. Relapsed neuroblastoma has been considered invariably fatal in the past , with a Recent data presented by Modak and colleagues and Manole and colleagues indicate that patients with isolated local recurrence can be treated successfully with surgical tumor resection and/or radiation therapy at sites of active disease ,7. TheseInitial treatment regimens for patients with relapsed or refractory neuroblastoma typically include chemotherapy combinations distinct from those previously used. Topotecan and irinotecan have both demonstrated activity as single agents in preclinical and clinical studies of neuroblastoma via inhibition of the topoisomerase I enzyme ,14,15,16Combinations of irinotecan with the alkylating agent temozolomide have also demonstrated efficacy in children with relapsed neuroblastoma. A single-institution study reported 2 complete responses to the combination of irinotecan and temozolomide among 19 patients with refractory disease, with 7 patients with mixed responses and 10 with stable disease (SD) . ChildreCombinations of ifosfamide, carboplatin, and etoposide (ICE) have also been routinely employed for children with relapsed neuroblastoma. In a single institution study, ICE was well tolerated and led to disease regression in 14 of 17 patients (82%) who were treated after their first neuroblastoma relapse. Disease regression was also seen in 13 of 26 patients (50%) with refractory neuroblastoma and in 12 of 34 patients (35%) who developed progressive disease during frontline treatment . In a sePrior studies have also suggested that some patients with relapsed or refractory neuroblastoma might benefit from more aggressive treatment consisting of myeloablative chemotherapy followed by autologous stem cell rescue (ASCR). One recent study demonstrated that children with relapsed neuroblastoma who received myeloablative therapy followed by ASCR had improved survival rates compared to those who received chemotherapy alone (43.5% vs. 9.6%), with 7 of 23 patients achieving either CR or PR after ASCR. However, 2 of the 23 patients experienced transplant-related mortality, suggesting that further studies to identify which patients would receive the most benefit from this approach are needed . Additio131I-MIBG used therapeutically in children with recurrent neuroblastoma showed overall response rates of 21–47% [131I-MIBG had either complete or partial responses, while another 34% of patients demonstrated stable disease with a median time to progression of 6 months [131I-MIBG therapy at a single institution demonstrated a 27% overall response rate. However, 24% of relapsed patients had progressive disease compared to only 9% of refractory patients, and 39% of relapsed patients had stable disease compared to 59% of refractory patients [131I-MIBG therapy. The efficacy of 131I-MIBG therapy against neuroblastoma has led to subsequent clinical trials incorporating 131I-MIBG therapy as a component of frontline treatment for children with high-risk neuroblastoma, and ongoing clinical trials through the New Approaches to Neuroblastoma Therapy (NANT) consortium are evaluating the efficacy of additional anticancer agents combined with 131I-MIBG therapy (NCT02035137) in children with relapsed and refractory neuroblastoma. Despite the established efficacy of 131I-MIBG therapy in children with relapsed neuroblastoma, however, only a limited number of institutions have the resources to support the administration of radioactive iodine to pediatric patients, and the limited availability and accompanying need for available stem cells for ASCR remain major challenges to the more widespread use of 131I-MIBG therapy.Additional forms of therapy for children with relapsed and refractory neuroblastoma have directly targeted markers expressed on the surfaces of neuroblastoma tumor cells. The vast majority of neuroblastoma tumors demonstrate tumor cell surface expression of the norepinephrine transporter (NET), suggesting that the use of benzylguanidine analogues, such as meta-iodobenzylguanidine (MIBG), that bind to this transporter would selectively target these neuroblastoma tumor cells . Approxif 21–47% ,35,36. Af 21–47% . Subsequf 21–47% . In a la6 months . A subsepatients , suggest111In-, 177Lu-, and 90Y-labeled somatostatin analogues has been successfully used [111In-DOTATATE, 177Lu-DOTATATE, or 90Y-DOTATATE. All four had objective responses, with two long-term survivors [Prior studies have also shown that 77–89% of neuroblastoma cells express the somatostatin receptor (SSTR) ,42,43, slly used ,45. In aurvivors , support131I-MIBG have demonstrated efficacy in the treatment of children with relapsed and refractory neuroblastoma, treatment options for children who suffer from subsequent disease relapses and progression remain limited. However, ongoing investigations exploring the molecular mechanisms underlying the etiology and pathogenesis of neuroblastoma have identified a number of novel therapeutic targets, and several novel targeted agents have been shown to be highly active in preclinical models of neuroblastoma. Many of these agents have been tested or are currently being evaluated in early phase clinical trials for children with relapsed and refractory neuroblastoma (While regimens incorporating chemotherapy and radiotherapy with blastoma . AlthougALK) gene [ALK gene mutations or gene amplifications in up to 15% of sporadic high-risk neuroblastoma tumors [ALK gene expression when compared to low-risk tumors [ALK mutations [ALK mutations, only 1 of 11 children with neuroblastoma with ALK mutations (9%) demonstrated an objective response, suggesting that ALK inhibitors will likely need to be combined with other therapies for maximal benefit. Initial studies have identified synergistic combinations of ALK inhibitors with mTOR inhibitors [F1174L mutant [ALK gene aberrations. To date, one patient with relapsed neuroblastoma with an ALKF1174L mutation had shrinkage of a retroperitoneal mass but concurrently experienced central nervous system (CNS) disease progression [Early efforts to identify gene mutations and other genetic aberrations in neuroblastoma tumors that could serve as therapeutic targets focused on familial neuroblastoma, which accounts for approximately 2% of all patients with neuroblastoma. Initial efforts determined that the majority of these cases are associated with activating germline mutations in the anaplastic lymphoma kinase (LK) gene ,50,51,52a tumors ,53. Highk tumors , furtherutations . Despitehibitors  and withhibitors , and theL mutant ,59 are cgression , suggestAdditional efforts to identify novel targets in neuroblastoma tumors have identified a critical role for mitotic spindle regulation in neuroblastoma pathogenesis, suggesting that regulators of the mitotic spindle represent potential therapeutic targets. Aurora A kinase represents one such potential target and is essential for appropriate completion of mitosis through regulation of the mitotic checkpoint complex . AberranOrnithine decarboxylase (ODC1), the rate-limiting enzyme in polyamine synthesis, is frequently deregulated in neuroblastoma tumors ,69 and rFurther studies in neuroblastoma preclinical models have confirmed a role for the PI-3 kinase/AKT/mTOR pathway in neuroblastoma pathogenesis. SF1126 is a pan-PI-3 kinase inhibitor that has been demonstrated to be effective against neuroblastoma in preclinical models , suggestEpigenetic modifications to DNA involve heritable genomic modifications that are not due to changes in the DNA sequence, including DNA and histone methylation and histone acetylation. These modifications influence chromatin structure and play a key role in regulating gene expression . EpigeneMYCN gene expression [Modulation of the epigenetic readers—proteins that recognize and bind to epigenetic chromatin modifications to modulate gene transcription—has recently emerged as a therapeutic strategy for anticancer treatment. Bromodomain and extraterminal domain (BET) proteins are epigenetic readers that regulate gene transcription, and BET inhibitors preferentially bind to super-enhancers—regions of DNA comprising multiple enhancers occupied by transcription factors and regulators of gene transcription that control the expression of genes critical for cell identity, growth, and survival . Furtherpression ,94. A nupression . BET inhTrypanosoma cruzi [in vitro and in vivo in preclinical studies, most likely via inhibition of ROS production [Reactive oxygen species (ROS) have been shown to impact a variety of critical intracellular signaling pathways, and prior studies have identified a role for ROS in cancer pathogenesis . Howeverma cruzi ,98. Nifuoduction ,100, andoduction , leadingoduction , and thecis-retinoic acid had one patient with neuroblastoma who had a CR following treatment [cis-retinoic acid for children with relapsed neuroblastoma found no objective responses, but 11 of 29 evaluable patients had SD, with 7 of the 11 receiving at least 11 cycles of therapy [in vitro and in vivo preclinical models of neuroblastoma [Retinoid therapy has been shown to increase EFS rates when used as a component of maintenance therapy for high-risk neuroblastoma , and stureatment , and a m therapy . Additio therapy . RET inhblastoma ,110,111,With the rapid advances in our understanding of the biology of cancer, the use of molecular tumor profiling to develop individualized treatment plans is increasingly employed for many adults with a variety of cancers . Althougcis-retinoic acid [Although a number of recent studies have demonstrated the efficacy of various forms of immunotherapy against neuroblastoma and other pediatric solid tumors, the role of immunotherapy in the treatment of patients with relapsed or refractory neuroblastoma is the focus of numerous prior and ongoing studies. Early studies demonstrated promising results for anti-GD2 antibody therapy in children with relapsed neuroblastoma ,119,120,oic acid .Further studies have attempted to expand the use of anti-GD2 antibody therapy in children with relapsed neuroblastoma by employing combinations with other therapies, in addition to the development and evaluation of modified forms of the antibodies themselves. A recent trial combining irinotecan and temozolomide with the anti-GD2 antibody dinutuximab demonstrated promising results, with 9 objective responses (including 5 with CR) among 17 patients receiving the combination . PrelimiOne of the drawbacks to antibody therapy for neuroblastoma is that neuroblastoma tumors use a variety of strategies to evade the host immune response, including downregulation or weak immunogenicity of target antigens and creation of an immune-suppressive tumor environment. With the significant side effects experienced by patients receiving anti-GD2 antibody immunotherapy and with the challenges of antibody administration to patients, a number of alternative immunotherapy strategies are currently under investigation. Immunomodulatory checkpoint inhibitors, such as ipilimumab and nivolumab, have been employed in adult cancers to overcome the immune-suppressive tumor microenvironment. Although ipilimumab was well tolerated in a phase I study for children with relapsed solid tumors, only one patient enrolled in the study had neuroblastoma, and no objective tumor regressions were observed . OngoingAnticancer vaccines have been tested in clinical trials for a number of different tumor types, and an early clinical trial of anti-neuroblastoma vaccine therapy showed the ability to induce an antitumor immune response, although the immune response was insufficient to induce tumor responses or prevent disease progression . A subseCD8+ T lymphocytes play a key role in cell-mediated immunity and, when infused as a form of immunotherapy, offer the advantage of direct tumor targeting that can avoid or overcome the tumor cell strategies to evade the host’s own immune system. Cell therapy with CD8+ T cells has been employed in early phase clinical trials for children with relapsed neuroblastoma, with some notable successes. EBV-specific T lymphocytes engineered to express a chimeric antigen receptor (CAR) directed against GD2 resulted in 3 patients with complete responses out of 11 total treated patients with active disease ,133. CARex vivo expanded haploidentical NK cells infused after haploidentical allogeneic stem cell transplants for children with solid tumors, including neuroblastoma (NCT02100891), and a recently opened clinical trial will explore the efficacy of expanded autologous natural killer T (NKT) cells engineered to express the GD2-specific CAR and IL-15 (NCT03294954). A trial using the hu14.18K322A anti-GD2 antibody combined with chemotherapy, cytokines, and haploidentical NK cells demonstrated a 61% response rate in 13 heavily pretreated patients, with 4 complete responses, 1 very good partial response, and 3 partial responses, in addition to 5 patients with stable disease and 10 of the 13 patients (77%) surviving for at least 1 year [Natural killer (NK) cells are another type of cytotoxic lymphocyte that can act in an MHC-unrestricted fashion to target cancer cells. Cell-based immunotherapy using NK cells for children with relapsed neuroblastoma has also been explored, particularly after the report of a child with relapsed neuroblastoma who received haploidentical donor NK cells combined with temozolomide, topotecan, and IL-2 and had a complete response . Ongoingt 1 year , demonstThe treatment of children with relapsed and refractory neuroblastoma remains a challenge, and the outcomes for these children remain poor despite decades of effort by clinicians and scientists. Recent advances in our understanding of the biology of neuroblastoma and of novel strategies to target tumor-specific pathways and antigens have led to a dramatic increase in the number of available treatment options for these patients and give hope that, in the future, novel treatment regimens will increase the responses of tumors to upfront therapy, limit the overall chances of relapse, and, in those hopefully rare cases of relapse, provide safe and effective therapies to eradicate neuroblastoma tumors. Continued development of novel therapies and therapeutic regimens directed against biologically relevant pathways and of novel approaches to harness the therapeutic potential of the innate immune system will provide new treatment strategies to improve the outcomes for these children.The relative paucity of therapeutically actionable gene mutations has limited the development of individualized treatment regimens for children with neuroblastoma, but as we obtain increased knowledge of other mechanisms of altered gene and protein expression and aberrant function in neuroblastoma tumors, we are likely to identify additional relevant therapeutic targets. Studies to further delineate the critical genetic and proteomic aberrations that either contribute to neuroblastoma pathogenesis or influence neuroblastoma tumor responses to treatment are ongoing, and these aberrations will hopefully lead to the development of individualized patient treatment regimens and also hopefully serve as targets for future drug development. A number of novel therapies directed against recently identified molecular targets are currently being evaluated both in preclinical models and in early phase clinical trials, and established national and international collaborations and cooperative groups will provide opportunities to evaluate these new treatments in carefully controlled clinical trials, leading to more precise and effective therapeutic regimens.The future holds promise for making considerable advances in our treatment of relapsed neuroblastoma, although continued difficulties in the management of metastatic, widespread relapse and in specific cases of isolated relapses, such as relapse in the CNS, represent ongoing challenges for the future. Although recent results need to be validated in future trials, these results do suggest that we should reconsider our treatment goals for many patients, particularly with the successes of treatments using extended maintenance therapy and immunotherapy for those patients who can achieve disease remission after relapse. Future treatment decisions need to be made based on not only the underlying diagnosis and clinical features of the patient, but also on the molecular features of the tumor itself and the feasibility and availability of tumor-specific treatment. The goals of future clinical and translational research should include identification and validation of the most effective treatment combinations, determination of the most appropriate patients and situations for use of effective therapies, and further delineation of the molecular subgroups of recurrent and refractory neuroblastoma to tailor treatment regimens to the patient populations most likely to benefit. Continued attempts to both develop novel therapeutic agents with efficacy against neuroblastoma tumors and to identify critical intracellular signaling pathways relevant for neuroblastoma pathogenesis and treatment resistance are underway, potentially leading to both individualized and improved treatment and to improved outcomes for children with relapsed and refractory neuroblastoma.


In general, no increases of maximal oxygen uptake (VO2max) were described. Ventilatory function improvements  achieved by using RMT fostered the capacity to adapt to hypoxia and minimized the impact of respiratory stress during the acclimatization stage in comparison with placebo/sham. In conclusion, RMT was found to elicit general positive effects mainly on respiratory efficiency and breathing patterns, lower dyspneic perceptions and improved physical performance in conditions of hypoxia. Thus, this method is recommended to be used as a pre-exposure tool for strengthening respiratory muscles and minimizing the adverse effects caused by hypoxia related hyperventilation. Future studies will assess these effects in elite athletes.Respiratory/inspiratory muscle training (RMT/IMT) has been proposed to improve the endurance performance of athletes in normoxia. In recent years, due to the increased use of hypoxic training method among athletes, the RMT applicability has also been tested as a method to minimize adverse effects since hyperventilation may cause respiratory muscle fatigue during prolonged exercise in hypoxia. We performed a review in order to determine factors potentially affecting the change in endurance performance in hypoxia after RMT in healthy subjects. A comprehensive search was done in the electronic databases MEDLINE and Google Scholar including keywords: “RMT/IMT,” and/or “endurance performance,” and/or “altitude” and/or “hypoxia.” Seven appropriate studies were found until April 2018. Analysis of the studies showed that two RMT methods were used in the protocols: respiratory muscle endurance (RME)  in three of the seven studies, and respiratory muscle strength (RMS) , 5–7 d/week) in the remaining four studies. The duration of the protocols ranged from 4 to 8 weeks, and it was found in synthesis that during exercise in hypoxia, RMT promoted (1) reduced respiratory muscle fatigue, (2) delayed respiratory muscle metaboreflex activation, (3) better maintenance of SaO Early studies on the influence of specific respiratory muscle training (RMT) upon exercise in healthy adults in normoxia provide convincing evidence supporting the ergogenic effect on endurance performance  ventilatory, between the environment and the alveoli; (2) pulmonary, between the alveoli and the blood; (3) circulatory, between arterial blood and muscle capillaries; and (4) peripherally, between muscle capillaries and mitochondria. In conditions of hypoxia, the physiological adjustments triggered in stages 1 and 2 cannot be compensated by equivalent changes in stages 3 and 4, as they can in conditions of normoxia. Therefore, although ventilatory function could be relatively well-preserved, this is not able to fully compensate the PaO2/SaO2 decrease with an existing impairment of the alveolar-capillary oxygen diffusion capacity   a brief description of the respiratory function during hypoxic exposure, (2) a brief description of the techniques of RMT, (3) an overview of the published literature pertaining to the effect of RMT upon exercise performance in hypoxia, (4) an insight into putative mechanisms underlying the ergogenic effects, and (5) suggestion for future investigations.A literature search was done in the electronic databases PubMed and Google Scholar using the keywords: “Respiratory/Inspiratory muscle training” AND “endurance performance” AND “hypoxia” OR “altitude”. Articles were selected according to the following criteria: published at any time before 18 April 2018; interventions in healthy active or sedentary people with hypoxic exposure; protocols including a control group (sham or placebo) or not; studies assessing exercise performance (pre- vs. post-intervention); and protocols based on specific respiratory muscle strengthening exercises. The following items were excluded: literature reviews; conference presentations; short communications and papers; references of book chapters or whole books; and articles not written in English. Due to the small number of studies published in the field, some criteria such as age, gender, residence altitude, or weight were not considered. All the data and methodological variables of the selected articles were initially recorded and analyzed by the first author and further discussed with co-authors.All of the cross-sectional studies discussed here  and gender/age may be relevant for the comparability of published results. Supplementary Table Two RMT protocols have been described in the studies included in this review: (1) Respiratory muscle strength (RMS) training (resistive load on inspiration); and (2) Respiratory muscle endurance (RME) training (resistive load on both expiration and inspiration at the same time) (ventilatory isocapnic hyperpnea). RMS includes high-force and low-velocity contractions, generating maximal muscle pressure capacity on inspiration and expiration against resistance . It is to highlight that such changes in MIP were only observed in the RMT groups but not in the control groups. Conversely, Esposito et al.  falls and hypoxemia develops within minutes of arrival. To limit the drop in the arterial oxygen content, cardiac output is elevated through sympathetic activation and alveolar ventilation is increased due to stimulation of peripheral chemoreceptors  together with a decrease in pulmonary artery pressure (PAP) was reported after the intake of medication as sildenafil or dexamethasone in hypoxic healthy volunteers  and maximal power (Watts) (−20%) compared to normoxia. Although two studies found improved VO2max in hypoxia after RMT, it remains uncertain whether RMT does really provide direct benefits on aerobic capacity and maximal performance in hypoxia/at altitude.When ascending to high altitude, the partial pressure of oxygen   during exercise in hypoxia, indicating less ventilatory needs to maintain a certain SaO2 level. Downey et al. found a post-RMT increase in pulmonary diffusion capacity (23%) as the cause for improved SaO2 . In response to this metabolic acidosis, the fall of arterial pH is constrained by the magnitude of the compensatory hyperventilation  increased during exercise in hypoxia without affecting high intensity endurance performance. However, the increased exercise ventilation did not result in a significant alteration of the regional cerebral and muscle oxygenation pattern or regional blood volume redistribution from the working leg to the respiratory muscles during hypoxic exercise.The connection between muscle contraction and cardiorespiratory responses is evident from the known activation in the discharge frequency of metabosensitive group III/IV, muscle afferents projecting to the cardiorespiratory control centers in the CNS , which were significantly decreased in the RMT group.Loading and unloading of the respiratory muscles during intense exercise have substantial effects on the perception of both respiratory and limb effort  more favorable blood redistribution to the locomotor muscles. Both normal trained persons and elite athletes may benefit from RMT. Particularly in some diseases as obesity, the main pathophysiological mechanisms involved in the impairment of the uptake and management of oxygen include a heightened demand for ventilation, increased work related to breathing, respiratory muscle inefficiency, and diminished respiratory compliance  when compared to the control group. The delayed onset of fatigue was partly attributed to the attenuation of reflex vasoconstriction of the locomotor muscles and a decrease in metabolite accumulation  is associated with increased energy costs (20–30%) when compared to normoxia . Hyperventilation is one of the factors contributing to the more pronounced perception of fatigue and dyspnea .In conclusion, RMT potentially represents an appropriate method to improve respiratory and exercise performance in hypoxia/altitude. RMT effects may include (1) reduced respiratory muscle fatigue, (2) delayed respiratory muscle metaboreflex activation, (3) better maintenance of SaOAll 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.


An association between periodontal disease and cancer has been established in recent studies, but no common etiology has been identified in the hopes of reducing the global burden of these non-communicable diseases. This perspective article hypothesizes that the determinant mediating the association of periodontal disease with cancer is dysregulated phosphate metabolism. Phosphate, an essential dietary micronutrient, is dysregulated in chronic kidney disease, and both cancer and periodontal disease are associated with chronic kidney disease. Reviewed evidence includes the association between phosphate toxicity and cancer development, and the association between periodontal disease and chronic kidney disease-mineral and bone disorder includes conditions such as ectopic calcification and bone resorption, which may be indirectly related to periodontal disease. Dental calculus in periodontal disease contains calcium phosphate crystals that are deposited from excess calcium and phosphate in saliva. Alveolar bone resorption may be linked systemically to release of parathyroid hormone in response to hypocalcemia induced by hyperphosphatemia. More research is needed to examine the role of dysregulated phosphate metabolism in periodontal disease. The global burden of periodontal disease, which accounts for the majority of the 442 billion USD spent on oral disease costs, share risk factors, and social determinants with other non-communicable diseases such as diabetes, heart disease, and cancer . Recent Despite consistent findings supporting a positive association between periodontal disease and cancer, replete with hypotheses implicating oral microorganisms and systemic inflammation, a common causal mechanism has not been identified in the etiology of these two non-communicable diseases. It is not clear if periodontal disease causes cancer, or cancer causes periodontal disease, or some other common pathophysiological determinant causes both diseases. This perspective article reviews evidence supporting a novel hypothesis that the association of periodontal disease with cancer may be mediated by the pathophysiological determinant of dysregulated phosphate metabolism. The reader should bear in mind that statements related to the proposed hypothesis in this article are hypothetical, and further research is required for acceptance or rejection of this hypothesis. The discovery of a common cause linking periodontal disease and cancer has possible global health implications, suggesting a reduction in the global burden of these non-communicable diseases by modifying their common lifestyle risk factors and determinants.2D3, increases intestinal absorption of dietary phosphate, mainly through enhanced expression of sodium-phosphate 2b cotransporters. Fibroblast growth factor 23 (FGF23) is produced within osteocytes and osteoblasts of bone. Working in conjunction with its co-factor, Klotho, FGF23 lowers serum phosphate levels, and increases urinary phosphate excretion by suppressing reabsorption through action of sodium-phosphate cotransporters in the kidneys. Phosphorus renal reabsorption is also decreased by parathyroid hormone (PTH). If phosphate is dysregulated due to kidney burden and excessive dietary phosphate intake, serum phosphate levels may rise (hyperphosphatemia) and excessive phosphate may be sequestered in cellular tissue producing a pathological condition called phosphate toxicity. Phosphorus, an essential dietary micronutrient, is ingested as phosphate in food and food additives. The highest amount of phosphate within the body is stored in bone as calcium phosphate. Levels of serum phosphate are regulated through a hormonal network, involving the kidneys, parathyroid glands, intestines, and the skeletal system . BioactiPhosphate toxicity is emerging as a global health concern as average amounts of dietary phosphate intake increase to approximately double the Recommended Dietary Allowance of 700 mg per day for an adult . An exceEvidence supporting the role of dysregulated phosphate metabolism and phosphate toxicity in tumorigenesis has been detailed elsewhere ,27; a veWhile serum phosphorus levels are not always a reliable indicator of phosphate stored in the body, a study of cancer patients found that they had abnormally higher serum phosphate levels compared to control patients . The Hea4H(PO4)3 · 2H2O, brushite = CaH(PO4) · 2H2O, hydroxyapatite = Ca5(PO4)3(OH), and whitlockite that contains a small amount of magnesium and other elements = β-Ca3(PO4)2 [The periodontium functions to connect teeth to bone; its structures consist of the cementum, periodontal ligament, gingiva, and alveolar bone. Periodontal disease is the most common cause of adult tooth loss . Many mea3(PO4)2 . While ga3(PO4)2 . As an alternative explanation for the development of periodontal disease and its association with cancer, Phosphate metabolism is often dysregulated in chronic kidney disease (CKD), and hyperphosphatemia contributes to patient morbidity and mortality . CKD is While severity of periodontal disease was found to increase with stages of CKD, serum albumin levels declined as periodontal disease severity increased . Of releHyperphosphatemia is a common condition in dialysis patients , and diaRecent studies confirm an association of systemic osteoporosis with periodontal disease ,70,71,72Explaining a common cause linking periodontal disease with cancer has possible global health implications, suggesting that a reduction in the global burden of these non-communicable diseases may be possible by modifying their common lifestyle risk factors and determinants. This perspective article hypothesizes that the association of cancer with periodontal disease may be mediated by the pathophysiological determinant of dysregulated phosphate metabolism related to high dietary phosphate intake and kidney burden. Evidence supports the role of phosphate toxicity in cancer development, and periodontal disease is an associated comorbidity with chronic kidney disease, in which systemic CKD-mineral and bone disorder is common. More research is needed to establish the role of dysregulated phosphate metabolism in periodontal disease.