The ability of horse chestnut extract (HCE) to induce contraction force in fibroblasts, a process with remarkable significance in skin repair, motivated us to evaluate its wound healing potential in a series of experiments. In the in vitro study of the ability of human dermal fibroblasts to form myofibroblast-like cells was evaluated at the protein level (Western blot and immunofluorescence). The in vivo study was conducted on male Sprague-Dawley rats with inflicted wounds (one open circular and one sutured incision) on their backs. Rats were topically treated with two tested HCE concentrations (0.1% and 1%) or sterile water. The control group remained untreated. The incisions were processed for wound tensile strength (TS) measurement whereas the open wounds were subjected to histological examination. On the in vitro level the HCE extract induced fibronectin-rich extracellular matrix formation, but did not induced α-smooth muscle actin (SMA) expression in dermal fibroblasts. The animal study revealed that HCE increased wound TS and improved collagen organization. In conclusion, the direct comparison of both basic wound models demonstrated that the healing was significantly increased following HCE, thus this extract may be found useful to improve healing of acute wounds. Nevertheless, the use of an experimental rat model warrants a direct extrapolation to the human clinical situation. Skin wound healing involves four basic steps: hemostasis, inflammation, proliferation, and maturation . EspeciaAesculus hippocastanum L. extracts (horse chestnut extract–HCE) improve the repair of venous ulcers ) and expressed in g/mm2.The measurement technique was described previously . BrieflyWound specimens were routinely processed for light microscopy , and staining with hematoxylin-eosin (HE)).Used semi-quantitative method was described previously . We evalp < 0.05 was considered to be statistically significant. The wound tensile strengths are expressed as mean ± standard deviation (SD) and were compared by one-way ANOVA, followed by Tukey–Kramer multiple comparison test. The non-parametric data from the semi-quantitative analysis are expressed as median and were compared by Kruskal–Wallis test. Level of In conclusion, the direct comparison of both basic wound models demonstrated that the healing was significantly increased following HCE, thus this extract may be found useful in improving acute skin wound healing. However, we did not observe a direct effect of HCE on fibroblasts to myofibroblast transition, and thus it is essential to perform further experiments aimed at finding the exact underlying mechanism of action and optimal therapeutic protocol. Finally, a direct extrapolation from this experimental model to the human clinical situation presents the third limitation of our study due to inter-species variability. However, general molecular regulation of wound healing should be similar, and thus the present data encourages further respective investigations in other animal models physiologically and evolutionary closer to humans.


While there is currently no specific treatment for COVID-19, several off label drugs approved for other indications are being investigated in clinical trials across the globe.On the 30In the last decade, theranostic nanoparticles were reported as promising tool for efficiently and selectively deliver therapeutic moieties  to target sites of infection. In addition, they allow monitoring infectious sides and treatment responses using noninvasive imaging modalities. While intranasal delivery was proposed as the preferred administration route for therapeutic agents against viral pulmonary diseases, NP-based delivery systems offer numerous benefits to overcome challenges associated with mucosal administration, and ensure that these agents achieve a concentration that is many times higher than expected in the targeted sites of infection while limiting side effects on normal cells.In this article, we have shed light on the promising role of nanoparticles as effective carriers for therapeutics or immune modulators to help in fighting against COVID-19. Figure . On 30 January 2020, the World Health Organization (WHO) Emergency Committee announced a global health emergency based on significant number of confirmed cases and on 11 February 2020 gave the disease an official name: COVID-19 (which stands for COrona Virus Infectious Disease - 2019). The virus has raised world concern because of its high transmission rate as well as high mobility and mortality Coronaviruses are a large group of viruses that belong to the Coronaviridae family. They were named for the crown-like spikes on their surface, and were reported to cause diseases in humans and few animal species with wide spectrum of severity. To date, four main sub-groupings of coronaviruses have been identified named alpha, beta, gamma, and delta Person-to-person transmission of SARS-CoV-2 is expected to occur mainly via respiratory droplets produced during coughing, sneezing and talking, and largely resembles the spread of influenza Studies have shown that patients with underlying diseases such as hypertension, lung disease, and cardiovascular disease may have higher mortality risk than other patients This article will first review the proposed conventional treatments that are currently under extensive research and clinical trials. Then, the advantages of theranostic nanoparticles with a special focus on the optimal formulations for intranasal administration of the various therapeutic agents will be discussed. Finally, a special focus will be devoted to the development of nanoparticles-based treatment modalities that are projected to considerably improve COVID-19 therapy.Currently, there are no validated vaccines or specific antiviral treatments for COVID-19. Most treatments currently used including cardiovascular/ hemodynamic or respiratory are supportive, that is, they support patients suffering from the virus. Unfortunately, these treatments are given to relieve complications and side effects, but do not efficiently kill the virus. Therefore, extensive research and clinical trials evaluating potential therapy are still imminently necessary.To develop a successful treatment for COVID-19, one must understand well the mechanism of action of the virus. Resembling SARS and MERS coronaviruses, this novel SARS-CoV-2 uses a “Lock and Key” mechanism in which the angiotensin converting enzyme II (ACE2) acts as a “key” to enter specialized cells holding its “lock” What is common about all target cells for SARS-CoV-2 is the AP2-associated protein kinase 1 (AAK1), a key regulator of endocytosis. Richardson P. et al. proposed, using a machine learning software BenevolentAI, that drugs associated with AAK1 may suppress viral access into the target cells Other potential inhibitors to fight COVID-19 include the complementary use of human immunodeficiency virus (HIV) protease inhibitors such as Lopinavir and Ritonavirin that have been shown to suppress the 3-chymotrypsin-like protease of SARS and MERS Other suggested alternative treatments under extensive investigation include virally targeted agents, mainly Remdesivir, a nucleoside analogue that targets the RNA-dependent polymerase and suppresses viral RNA synthesis in a broad spectrum of RNA viruses, including human coronaviruses. Remdesivir is an approved HIV reverse transcriptase inhibitor that has shown broad-spectrum activities against RNA coronaviruses in cell cultures and animal models A very promising treatment option that started to be applied in several countries involved the use of Chloroquine or Hydroxy-Chloroquine, antiviral and wide spread drugs previously used against malaria and autoimmune diseases However, despite these proposed treatment options currently under extensive research and clinical trials, the death toll of patients infected with this novel coronavirus is still increasing. Therefore, efforts should in parallel focus on alternative approaches in order to achieve an effective treatment while minimizing side effects. Although mucosal vaccination, mostly intranasal, is the preferred route of vaccination against infectious diseases, treatment modalities currently under investigation use the systemic route. This is mainly because intranasal treatment needs to overcome many hurdles, such as low intrinsic permeability for some drugs, limited volume of administration, rapid mucociliary clearance, and enzymatic degradation, before they reach the targeting site due to the unique characteristics of the mucosal environment. Therefore, the delivery of most proposed therapies to specific sites of the body by means of nanoparticles (NP) ensures that these agents achieve a concentration several times higher than those obtained via conventional methods in the targeted sites of infection while limiting any side effects on normal cells.In the last decade, theranostic nanoparticles have emerged as a new field of medicine combining specific targeted therapy based on diagnostic tools for the next generation treatment of several diseases. The low toxicity, added to the size, charge, and chemical modification capabilities of these nanoparticles, allow them to overcome the multiple barriers that impede their way following various administration routes. More specifically, extensive efforts have focused on the development of a NP-based intranasal delivery system as an effective and safe tool to deliver several therapeutic moieties  Mucosal treatment is highly desired for infectious diseases since most pathogens initiate their infections at the human mucosal surface. Intranasal delivery allows for noninvasive, practical, simple, and inexpensive administration of therapeutic agents. The large surface area and rich capillary plexuses also allow for their quick absorption While the nanoparticles' pharmacokinetic properties are mainly governed by their characteristics, the shape, size and surface charge of the designed nanocarriers are considered as crucial factors that should be taken into consideration when optimized for intranasal delivery and thus play a crucial role in the success of the treatment. Several studies were performed to identify the optimal characteristics of the theranostic nanoparticles for pulmonary intranasal administration and were recently reviewed It is worth noting that majority of studies performed to assess the use of nanoparticles as delivery system following intranasal pulmonary administration are mostly based on preclinical data performed on small animal and cannot be readily generalized to humans. However, the investigations provide some promising forecasts for prospective clinical applications with theranostic nanoparticles.Figure .Several types of theranostic nanoparticles were proposed as promising for intranasal administration. They can be divided into 3 broad categories: organic, inorganic, and virus-like or self-assembling protein nanoparticles Nanoparticles made from lipids are particularly attractive for biomedical applications owing to their enhanced biocompatibility imparted by the lipid material. Among the various lipid-based formulations adapted for intranasal delivery are liposomes, which are spherical capsules having an outer phospholipid bilayer and an inner hydrophilic core designed to hold aqueous therapeutic agents in vivo, capability to open up tight junctions between epithelial cells Polymer-based nanoparticles were reported as an attractive delivery system mainly due to the possibility of tailoring their properties and functions to a specific application. They can be synthesized by the addition of several monomers into various configurations including linear, branched, and 3D networks (i.e. highly branched) Dendrimer are radially symmetric molecules with well defined, homogeneous, and monodisperse structure. Similar to Polymer, Dendrimer NP can be synthetized in highly branched 3D networks with greater ability of attaching many functional groups on their surface, and encapsulating non-water soluble, hydrophobic therapeutic agents in their core With the strong interactions that they make with viruses, dendrimers showed enhanced antiviral activities, preventing the infection of the host. Consequently, they became an important tool in the treatment of viral infections such as HIV and influenza virus infections Nandy B. et al. reported the development of Poly-L-lysine (PLL)-based dendrimeric nanoparticles with anionic naphthalene disulphonate surface that can block the entry of HIV viruses by binding to the viral envelope protein gp120 and preventing the formation of the CD4-gp120 complex in vivo administration to human body using noninvasive medical imaging Engineered inorganic nanoparticles are attracting special interests due to their ability to not only act as conventional delivery systems to efficiently deliver loaded cargo to target sites, but also to allow stimuli-responsive characteristics and intrinsic capability of some types (i.e. Magnetic or Gold Nanoparticles) to be monitored following Gold nanoparticles have shown special interest in vaccine development as they can easily trigger the immune system via internalization by antigen presenting cells. The synthesis methodologies, significant progress, and future prospects of the use of Gold NP for new mucosal vaccines were reviewed Virus-like NP (VLNP) are sphere-shaped nanoparticles composed of several molecules with sizes ranging between 20 and 200 nm. These nanoparticles result from the self-assembly of proteins derived from viral capsids. They were introduced as attractive nanomaterials as they do not contain genetic material but have the ability for accurately mimicking the real virus or antigen in terms of structure and antigenic determinant(s). This makes these nanomaterials highly attractive to antigen presenting cells that can be readily identified and consequently can trigger an immune response Self-assembling protein nanoparticles (SAPN) are novel type of NP obtained from the oligomerization of monomeric proteins with a dimeter ranging from 20 to 100 nm. Self-assembly is defined as the autonomous organization of molecules into a more stable structure by using non-covalent bonding mechanisms to achieve equilibrium Kanekiyo M. et al. reported the synthesis of SAPN that elicit broader and more effective immunity (i.e. tenfold higher haemagglutination inhibition antibody titres) than traditional influenza vaccines following intranasal inoculation, and thus provide a promising platform for developing broader vaccine protection against emerging viruses and other pathogens The use of NP in the medical field holds great promise in developing novel theranostic and diagnostic solutions for treating COVID-19. It is out of the scope of this review to discuss the innovative solutions that NP can offer in fighting against coronavirus such as the development of disinfecting spray that have the ability to kill the virus on the surface, or detection tools (i.e. rapid screening test).Figure .As SARS-CoV-2 has a diameter of around 125 nm fitting in the nanoscale size range, biocompatible theranostic NP can thus be very promising to simultaneously detect and neutralize this novel coronavirus by several approaches as previously investigated against various viral infections including SARS or MERS coronaviruses As previously mentioned, drugs associated with AAK1 may suppress virus access into the cells. However, high doses of these suppressors such as oncology drugs (Sunitinib and Erlotinib) will be required but could unfortunately lead to serious side effects. Therefore, the use of NP as smart nanocarriers that can selectively enhance the delivery of such drugs to target cells will certainly reduce the required doses and arising side effects while providing a more efficient treatment.in vivo administration in the body (i.e. 3 months stability), and significantly increase the relative bioavailability of the drug (i.e. fast and sustained release within the first 4 hours) Drug Delivery System (DDS) conjugated with either Sunitinib Since coronaviruses are positive ssRNA viruses that use ORF1a and ORF1b replicases, RNA interference (RNAi) could be an efficient approach to control the virus by silencing the viral mRNA at particular stages in human cells siRNA were reported as a very successful candidate to fight against viruses as they can be identified, designed, and synthesized to attack every possible viral mutation Sohrab S. et al. recently reviewed the design and delivery of therapeutic siRNAs for treating MERS-Coronavirus The effective delivery of siRNA via lipid nanoparticles revealed promising results against several viral diseases Inorganic nanoparticles such as gold, magnetic iron oxide, and silica nanoparticles, in addition to quantum dots (QDs) and carbon nanotubes (CNTs) were evaluated as potential carriers for siRNA Polymeric nanoparticles, either natural (i.e. chitosan) or synthetic (i.e. polyethyleneimine (PEI)), have been also assessed as drug or gene carriers and can be potentially used to specifically deliver siRNA in COVID-19 cases. Chitosan-based NP have proven efficient in inducing protective immunity against various infectious diseases As previously discussed, knowing SARS-CoV-2 infection mechanism will help developing a successful treatment. Luckily, MERS-CoV and SARS-CoV-2 share the same membrane protein (the “key”) which is the Spike Protein (S protein). Therefore, both viruses infect host cells using the S protein mediated fusion between their membranes Huang X. et al. proposed the use of Pregnancy Induced Hypertension (PIH) as powerful heptad repeat 1 (HR1) peptide inhibitor that suppresses HR1/HR2-mediated membrane fusion between MERS coronavirus and host cells as the key pathway of MERS-induced host infections. They showed that this peptide inhibitor when delivered via gold nanorods revealed 10 times enhanced inhibitory activity when compared to free PIH With the continuous evolution of new and mutated strands of viruses, the development of effective and safe antiviral treatments to that specific strain becomes more challenging due to the variation in their genetic compositions and the need for specific antiviral agents. Theranostic nanoparticles can also play a major role in, not only killing the virus inside the body, but also preventing the virus entry into the cells. Owing to their high specific surface area and the ability to adhere to multiple antigens and/or compounds on their surface, nanomaterials such as gold NP and Carbon Quantum Dots (CQDs) were reported as promising tools for interacting with viruses and preventing their entry into cells A study carried on Boronic acid conjugated Carbon dots NP demonstrated efficiency and success in inhibiting HIV entry by suppressing syncytium formation With the significant advances in vaccine development, great interest and huge efforts have focused on developing vaccines that mimic the virus using virus-like nanoparticles (VLNP). NP were reported to enhance transport in the lymphatic system compared to smaller subunit antigens NP are known for their high surface energy that leads to strong adhesion of biomolecules In a study combining 100 nm gold NP with the S protein of Infectious Bronchitis Virus (IBV), Chen H. et al. reported increased stability when using the developed VLNP, as well as significant retention of these S proteins (about 900 S proteins per particle) compared to viral antigens in vivo in mice. These studies proved the promising advantage of NP conjugated with S protein as a potential and successful vaccine, to not only stimulate the immune system, but also to protect humans from MERS-CoV, and thus can be applied to SARS-CoV-2 as both coronaviruses have the same key (i.e. Spike protein).In another study, Coleman C. et al. reported protection induced by vaccination with a recombinant MERS-CoV S NP vaccine and Matrix-M1 adjuvant combination that were able to efficiently and completely block MERS-CoV replication in the lungs of mice The highly contagious novel coronavirus SARS-CoV-2 that has infected so far more than 2 million people in 210 countries triggered an unprecedented economic crisis as a consequence of forced lockdown to limit the transmission, and put the life of many infected people at high risk around the world. COVID-19 patients are mainly managed with supportive care that includes cardiovascular/ hemodynamic or respiratory procedures. While there is currently no specific treatment for COVID-19, several drugs approved for other indications are being investigated in clinical trials. These treatments are based on the administration of agents that either block the virus entry inside the host cells stopping virus replication and infection of other cells, or potentially inhibit protease activity . Other potential treatments under clinical investigations use either nucleoside analogues that target the RNA-dependent polymerase suppressing viral RNA synthesis (i.e. Remdesivir), or directly act on the virion assembly and budding and alter the molecular crosstalk of SARS-CoV-2 while indirectly reducing the production of pro-inflammatory cytokines and/or activating anti-SARS-CoV-2 CD8+ T-cells (i.e. (Hydroxy)-Chloroquine). However, despite some promising results, the death toll of infected patients is still increasing.Although the administration of proposed conventional treatment is mainly performed via intravenous route, as intranasal administration faces several challenges associated with mucosal environment, the use of Nanoparticle-based delivery system ensures effective treatment while minimizing side effects of therapeutic agents. The theranostic nanoparticles ensure that therapeutic moieties such as drugs, vaccines, siRNA and peptide achieve a concentration that is many times higher than expected in the targeted sites while protecting the therapeutic agents from enzyme degradation. Several types of theranostic nanoparticles that can be divided in 3 broad categories organic , inorganic (i.e. gold), and virus-like or self-assembling protein nanoparticles, were investigated for intranasal administration. The shape, size and surface charge of the designed nanocarriers are considered as crucial factors that should be taken into consideration when optimized for intranasal delivery and thus play a crucial role in the success of the treatment.Delivered via intranasal route, biocompatible theranostic nanoparticles can thus be a very promising approach to fight against this novel SARS- CoV-2 as previously investigated against various viral infections including SARS or MERS coronaviruses using several approaches. Theranostic nanoparticles can enhance the delivery of therapeutic drugs, ensure selective and specific delivery of siRNA, efficiently delivery peptide inhibitors, prevent coronavirus entry into cells, and stimulate cells' immune system.Investigating the various promising therapeutic agents currently under development against SARS-CoV-2, delivered via biocompatible theranostic nanoparticles via intranasal route is expected to be far more efficient than any other treatment for COVID-19 treatment.


This Special issue contains 48 contributions highlighting novel findings and current concepts in basic and clinical liver fibrosis research. These articles emphasize issues on pathogenesis, cellular mediators, modulators, molecular pathways, disease-specific therapies, scoring systems, as well as novel preclinical animal models for the study of liver fibrogenesis. This editorial aims to briefly summarize the content of these papers. Liver fibrosis and associated complications bring substantial medical and economic burdens worldwide . This prWorldwide, liver research aims to increase basic knowledge, improve diagnostics, and try to translate experimental findings into new treatment modalities. However, based on the overall complexity of molecular and cellular events changing during initiation and progression of hepatic fibrosis, research of scientists and healthcare professionals covers a wide array of different and complex issues. Nevertheless, there is great hope that basic and translational research in this area will lead to new therapies in the near future.In this Special Issue, leading experts from the field share new findings and concepts of the current state in experimental and clinical liver fibrosis research. In total 319 scientists from 25 countries  contributed original or review articles about current perspectives and findings in hepatic fibrosis . These aGeneral mechanistic concepts of liver fibrosis and therapeutic consequences and perspectives resulting thereof are summarized by Roehlen and colleagues . They inAtp8b1G308V/G308V) promoted liver fibrosis [iPla2β) show exaggerated liver fibrosis when fed a methionine-choline-deficient diet. Ming and colleagues have now demonstrated that respective mice show severely disturbed endoplasmic reticulum phospholipid composition, increased unfolded protein response, suppression of farnesoid X-activated receptor (Fxr) expression, and exacerbated bile acids in the liver and blood combined with ductular proliferation [Five contributions address aspects of bile acid functions in hepatic health and disease. There is ample evidence that alterations in bile acid metabolism are closely linked to NAFLD and NASH. The review by Gottlieb and Canbay focusses on the complexity of the liver-bile-intestinal axis, promising clinical targets to tackle bile acid dysbalances in NAFLD/NASH, and pharmaceutical strategies evolving positive effects on bile acid composition . Klindt fibrosis . Since tferation . TherefoPin1 in the pathogenesis of NAFLD/NASH [Pin1 inhibitor counteracting these activities would be of fundamental therapeutic use in the treatment of NAFLD/NASH. Mahli et al. showed that micellar solubilized Xanthohumol is more effective in improving metabolic syndrome and NAFLD symptoms than native Xanthohumol in a mouse model fed with a Western diet for 3 weeks [Currently, there are no efficient strategies for the treatment of NAFLD/NASH. However, there are some potential targets and early drug candidates in the pipeline of researchers. Inoue and co-workers present a comprehensive review of the function of FLD/NASH . This pe 3 weeks . As discNowadays, the knowledge on molecular mechanisms by which individual genes modulate hepatic steatosis and fibrosis is growing steadily. Wang et al. report new findings about the role of vimentin in regulating HSC proliferation and migration during hepatic fibrogenesis in dimethylnitrosamine-exposed rat livers . The autAnother critical mediator involved in control of HSC migration is Oncostatin M (OSM). This is documented by experiments performed by Foglia and colleagues . They foInflammation is one important driver and promoter of liver fibrosis. As outlined by Ignat et al., there are many different pathways and cells stimulating the release of pro-inflammatory cytokines during hepatic fibrogenesis . In theiDuring alcoholic liver disease, inflammation, cell proliferation, migration and fibrogenesis are further triggered by Akt serine/threonine kinase isoforms . The autThe impact of oxaliplatin on the pathogenesis of porto-sinusoidal vascular disease (PSVD) is discussed by Puente et al. This cancer drug is commonly used for treatment of colorectal cancer. Like other platinum compounds, it evolves non-targeted cytotoxic defects that might rarely result in PSVD. In their review, the authors discuss the three underlying mechanisms  through which oxaliplatin causes sinusoidal damage and increase portal pressure during PSVD .Schmidt-Arras and Rose-John discuss fibrosis-associated pathways regulated by members of the ‘A Disintegrin And Metalloprotease’ (ADAM) family . These aHintermann and Christen review the literature on selectins, cadherins, integrins and members of the immunoglobulin superfamily of adhesion molecules in the context of hepatic fibrosis . ParticuFhl2-deficient mice develop significantly more hepatic damage and inflammation when subjected to bile-duct ligation than normal control mice. In HepG2 cells, the depletion of Fhl2 affected expression of key enzymes of bile acid metabolisms and hepatocellular injury. These finding suggest that FHL2 is important for liver homeostasis and more than just a simple scaffolding protein.Similarly, novel important functions were shown for the four-and-a-half LIM-domain protein 2 (FHL2) supposed to act as a scaffolding protein. Sommer and colleagues now provide novel insights in the role of FHL2 in cholestatic liver injury with a special focus on hepatocellular damage and fibrosis . The autIn another contribution, Seo et al. found that clusterin reduces hepatic fibrosis. They could demonstrate that this multifunctional glycoprotein inhibits activation of HSC in a thioacetamide-induced liver fibrosis model and TGF-β signaling pathway and collagen expression in primary mouse HSC or immortalized human HSC cell line LX-2 . Many prIn hepatic fibrosis, the endocannabinoid and apelin systems are two of the multiple cell signaling pathways involved in the transformation of quiescent HSC into MFB. Both systems are upregulated during liver diseases and contribute to the development of hepatic fibrosis. The review of Melgar-Lesmes and colleagues summarizes the recent advances in understanding pathophysiologically relevant roles and their potential clinical relevance of both systems. Interestingly, the endocannabinoid and apelin pathways have marked dissimilarities and collaborate with each other in hepatic fibrogenesis .Actually, a large number of studies use ‘omics’ or ‘multi-omics’ approaches to depict the complex sequence of events during hepatic fibrosis. The recent findings of metabolic alterations relevant to hepatic fibrosis obtained in selected studies were summarized by Chang and Yang . The autSchistosoma japonicum [+ T cells, which mediate important immunopathogenic roles in Schistosomiasis.In the Special Issue, several novel antifibrotic-acting drugs are discussed. Zhou and colleagues report that the selective RhoA/Rho-kinase (ROCK) inhibitor fasudil reduced the granuloma size, effectively promoted HSC apoptosis and inhibited expression of hepatic fibrogenic genes in mice infected with aponicum . ImportaKöse-Vogel et al. report novel findings about tissue-resident macrophages in promoting development of fibrosis in sterile tissue injury . In theiMilito et al. provide a reference collection on experimentally tested natural sulfur-containing antifibrotic compounds . Most ofTwo contributions in this Special Issue deal with aspects of microRNAs (miRNA) in liver fibrosis. These are non-coding, approximately 22 nucleotides long, single stranded RNA structures acting as posttranscriptional gene regulators. Lambrecht and coworkers performed miRNA-profiling in extracellular vesicles obtained from the conditioned medium of in vitro activated primary murine HSC. They produce a list of four miRNAs  that were significantly upregulated during HSC activation and in murine livers treated with carbon tetrachloride. Importantly, these molecules were also upregulated in serum obtained from patients with chronic alcohol abuse, chronic viral hepatitis infection, and NAFLD . Based oSimilar to miRNAs, posttranslational modification (PTMs) of proteins, and more specifically NEDDylation and SUMOylation ubiquitin-like (Ubls) modification have been shown to contribute to the progression of hepatic fibrosis . AlthougThe finding that men and postmenopausal women have a higher risk of NAFLD/NASH than premenopausal women is not well explained. The review by Lee and colleagues summarizes recent studies in which estradiol was supposed as the critical compound for developing these gender- and reproductive state-dependent differences in NAFLD/NASH . They diMahli and colleagues investigated aspects of the bone morphogenetic protein-8B (BMP-8B) in NAFLD. This cytokine belongs to the TGF-β superfamily and is expressed in brown adipose tissues and the hypothalamus modulating thermogenesis and susceptibility to diet-induced obesity. Mahli et al. now show that BMP-8B expression is induced in hepatocytes when cultured in the presence of fatty acids, in a murine NAFLD model, and in NAFLD patients . MoreoveMalik et al. postulated altered liver mitochondrial DNA (mtDNA) content is an early event preceding mitochondrial dysfunction and irreversible liver damage in NAFLD . In theiPresently, a main research focus in fibrosis research is the development of targeted therapies with high liver specificity that are tolerated and promote the removal of excess interstitial matrix. In this Special issue, two reviews discuss the most recent advances in using viable cells, magnetic particles, or controlled magnetic forces in therapy of hepatic fibrosis ,41. In tHFE) or transgenic for the PiZ variant of α1-antitrypsin, which in humans predispose for pulmonary emphysema and liver disease. The authors could show that the loss of HFE had no impact on PiZ variant accumulation, iron accumulation, or development of hepatic fibrosis [HFE mutations are not associated with increased liver injury in patients carrying the homozygous PiZ variant.In biomedical research, there is an urgent need to improve animal models to better reproduce and mimic the disease patterns of human inflammatory disease . This isfibrosis . AlthougRecent work from many laboratories has shown that HSC/MFB in healthy and diseased liver is not just a unique cell fraction, but rather, a heterogenous population made up of a number of different cell subsets . The repDuring liver damage, various immune cells are triggered to produce high quantities of cytokines, chemokines, and enzymes that further provoke liver damage. Presently, mast cell involvement in the pathogenesis of hepatic fibrosis is becoming more accepted as reviewed in a contribution of this Special Issue . They ar2-adrenergic receptor signaling [2A, α2B, α2C) and has important roles in catecholamine signaling in different structures of the central nervous system. Interestingly, the different subtypes showed differential expression in carbon tetrachloride or bile duct-ligated mice, while the α2-adrenoblocker mesedin reduced profibrogenic markers and α2A expression in culture murine HSC [2-adrenergic receptor system to contribute to liver fibrosis by alleviating HSC activation and increasing the permeability of liver sinusoids during liver injury [2-adrenergic receptor system will have potential therapeutic implications.Increasing evidence suggests alterations in mutual biological communication between distant organs as additional factors negatively impacting organ homeostasis, systemic inflammatory response, and fibrosis. The ‘heart-liver axis’ for example mediates the bidirectional communication between heart and liver and affects many aspects of inter-cellular and inter-organ communication related to inflammation and systemic energy metabolism. El Hadi and colleagues explain how acute and chronic heart failure can lead to acute hepatic injury and chronic congestive hepatopathy and vice versa, how liver disease can provoke the development of heart systolic and diastolic dysfunctions . As the ignaling . This rerine HSC . Moreover injury . It is nMdr2−/−) mouse model to investigate how liver fibrosis influences lobular zonation [The Special Issue includes novel findings of important anatomic aspects of liver fibrosis. Ghallab et al. used a toxic  a surgical (bile duct ligation for 21 days) and a genetic (zonation . The autzonation . SignifiCells commissioned me to edit a second Special Issue on that discipline. The Special Issue “Cellular and Molecular Mechanisms Underlying the Pathogenesis of Hepatic Fibrosis 2020” is now open for submission. Research articles, reviews, or shorter perspective articles from experts on all aspects related to this topic are highly welcomed.This Special issue received a high number of submissions showing that liver fibrosis is still a hot topic in Hepatology research. Therefore,


The COVID-19 pandemic has recently been the cause of a global public health emergency. Frequently, elderly patients experience a marked loss of muscle mass and strength during hospitalization, resulting in a significant functional decline. This paper describes the impact of prolonged immobilization and current pharmacological treatments on muscular metabolism. In addition, the scientific evidence for an early strength intervention, neuromuscular electrical stimulation or the application of heat therapy during hospitalization to help prevent COVID-19 functional sequels is analyzed. This review remarks the need to: (1) determine which potential pharmacological interventions have a negative impact on muscle quality and quantity; (2) define a feasible and reliable pharmacological protocol to achieve a balance between desired and undesired medication effects in the treatment of this novel disease; (3) implement practical strategies to reduce muscle weakness during bed rest hospitalization and (4) develop a specific, early and safe protocol-based care of functional interventions for older adults affected by COVID-19 during and after hospitalization. The World Health Organization (WHO) has declared the novel coronavirus SARS-CoV-2 (hereinafter COVID-19) disease a global pandemic. It menaces current lifestyle and is prompting irreversible consequences in health, economic and social stability. This novel coronavirus can produce severe disease symptoms among people of all ages; however, it has been evidenced that older adults with multi-morbidity are at the highest risk of poor prognosis due to COVID-19 .Common complications from COVID-19 infection are acute viral pneumonitis evolving to acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), proinflammatory hypercoagulable state with thromboembolic events, sepsis and cardiac injury. Complications are believed to derive from a pro-inflammatory state with cytokine release ,5. It is noteworthy that COVID-19 infected patients tend to experience a prolonged hospitalization or intensive care unit (ICU) stay, with an average of three weeks in the ICU . CommonlThe sequelae of prolonged immobility on SARS patients’ musculoskeletal system has been previously documented ; howeverIt seems important to keep in mind that the aging process is accompanied by an inherent sarcopenic process, characterized by an accelerated loss of muscle mass. Hence, the risk of suffering sarcopenia and fragility increases with age . UnfortuThus, the purpose of this paper was to (1) determine which potential pharmacological interventions have a negative impact on muscle quality and quantity; (2) define a feasible and reliable pharmacological protocol to achieve a balance between desired and undesired medication effects in the treatment of this novel disease; (3) implement practical strategies to reduce muscle weakness during bed rest hospitalization and (4) develop a specific, early and safe protocol-based care of functional interventions for older adults affected by COVID-19 during and after hospitalization.Empirical therapies including glucocorticosteroids as immune-modulatory agents are being prescribed . MoreoveThe delicate clinical condition due to the risk of respiratory failure warrants its use. However, as they usually induce a wide range of side effects, adverse outcomes derived from their use are observed and should be managed accordingly.Past studies have suggested that the use of systemic corticoids for treating acute lung injury during the 2003 SARS-CoV emergency contributed to muscular weakness and decreased functional capacity observed in survivors at follow-up visits . It is iSteroid-induced myopathy is most frequently observed in patients treated with >10mg/day of prednisone or its equivalent for a few weeks . GeneralFinally, it seems important to remark that certain pharmacological interventions used in the ICU environment may further exacerbate muscular damage. For example, the use of B-adrenergic vasoactive agents such as norepinephrine to treat circulatory failure has been independently associated with ICU-acquired weakness . The usep = 0.004, knee flexion p = 0.003 and stair ascent power p = 0.01) after 10 days of bed rest in healthy elderly people (60–85 years old).It has been evidenced that the hospitalization rates for COVID-19 increase with age and that older adults are at the highest risk of hospital admission . For manIt should be noted that older patients are especially vulnerable to these changes, with a higher risk of functional dependence loss and cognitive decline after discharge . In factAgeing is accompanied by an inherent sarcopenic process characterized by an accelerated loss of muscle mass and function; however, prolonged bed rest with muscular disuse can precipitate this “catabolic crisis” causing skeletal muscle atrophy (low muscle mass and low muscle function) . Thus, aStudies have shown how absolute rest can lead to various adverse effects such as changes in total muscle mass, metabolic activity, muscle denervation and a loss of contractile force with increasing fatigue and reduced muscle strength ,32 Figu.The aetiology of the coronavirus-related muscle weakness in hospitalized older patients seems to involve several interdependent processes. Firstly, a long period of bed rest seems to be predominant in COVID-19 patients. It is known that becoming temporarily bedridden with a lack of muscular weight-bearing activities is usually followed by an alteration in muscular protein homeostasis. This imbalance may occur quickly and be secondary to an accelerated muscle protein breakdown and a suppression of muscle protein synthesis . This ca2 is only one part (and not the most important one) of the story. The main cause of the acute reduction of VO2max during bed rest is a marked reduction of cardiac output, i.e., of the capacity to deliver O2 to the working muscles. Cardiac output is markedly reduced because of a reduction in pre-load  and contractility of the heart. While muscle deterioration takes weeks to happen, at least in healthy individuals, the loss of VO2max resulting from a drop in cardiac output is very rapid (1% loss per day from day one of bed rest) [Other factors such as cellular bioenergetics are also involved. It is believed that mitochondrial dysfunction may play an important role in the physical function impairment observed in COVID-19 patients. Muscle mitochondria deterioration and therefore the muscle’s capacity to utilize Oed rest) .Absolute bed rest, mechanical ventilation and the hyperinflammation status in elder patients can trigger a reduction in muscular mitochondrial content and a decrease in phosphorylation enzyme activity. Patients’ fatigue resistance and endurance capacity reduction after recovery is attributed to these processes ,37,38.Remarkably, clinical practice and research articles point out that the virus itself can cause myopathic changes unrelated to pharmacological treatment or a critical illness state. Leung et al. reported muscle atrophy and focal necrosis in infected patients based on muscular tissue samples, suggesting that a few of these changes may be the consequence of the activation of local cytokine-mediated pathways alone . There iThe evaluation of muscle weakness is recommended to tailor the intervention strategies and to assess their effect. Muscle weakness covers both muscle function and muscle structure. Muscle function is underlined by the three concepts of muscle strength, muscle power and muscle endurance. Muscle strength is measured routinely in clinical settings especially for the diagnosis of sarcopenia and frailty. Handgrip strength is the most used choice for the assessment of overall muscle strength . It is aThis scenario highlights the necessity of awareness of the harmful effects of prolonged rest and the factors aforementioned in order to prevent the functional decline in frail and non-frail ICU-admitted or hospitalized patients who are infected by COVID-19.Two phases have been identified in hospitalized patients. The first acute phase is characterized by a respiratory syndrome and the second, more prolonged phase, prevailing the neuromotor sequelae and impaired functional status. Muscular structure and neuromuscular function decrease exponentially with a combination of pharmacological treatment, extended bed rest and mechanical ventilation, as previously mentioned. Preventative non-pharmacological actions have been proven to positively impact long-stay patients; however, early intervention is frequently underutilized. The negative consequences in health of this scenario highlight the importance of an early health intervention in elderly people hospitalized with COVID-19.Before implementing any interventions requiring close patient contact, a protocol must be established and adhered to in order to prevent virus transmission. For instance, all masks and materials, namely, machines, elastic bands and dumbbells, must be sterilized before and after use. Both the patient and the healthcare professional must follow general hygiene measures including using disposable tissues when coughing or sneezing, washing and disinfecting hands thoroughly and maintaining physical distance when possible. It is also imperative that the healthcare professionals use single use disposable gloves, wear a disposable fluid-resistant coverall/gown, a face mask respirator (FFP2/FFP3), eye/face protection, overshoes and protective headgear. In addition, cleaning and disinfection procedures should be applied in hospital rooms regularly in order to prevent and control the spread of pathogens. Specifically, health services should implement environment restructuring measures , provide hand sanitizers or washbasins thoroughly inside facilities, schedule specific cleaning times, schedule training times, encourage the use of individual bottles and observe air conditioning specification with respect to air exchange ,47.The following section provides scientific evidence of early functional beneficial interventions among hospitalized older adults. Physical function reduction in patients hospitalized with chronic diseases is preventable; advanced age, acute and chronic disease and illness, functional limitations and deconditioning all contribute to older adults’ vulnerability to functional decline during hospitalization . As a reAmong the elderly, despite there not being a standardized exercise strength protocol, an intervention of low to moderate resistance training appears to be the most effective to fight against the loss of muscle mass, strength and functional capacity . CourtneThe positive effects of an early intervention in patients hospitalized with pneumonia have been also been reported . TherefoIdeally, it should be implemented as soon as possible to obtain the maximum benefit. However, during the COVID-19 acute phase, the risk of rapid desaturation lies with changes in position that can potentially alter the ventilation/perfusion ratio and hemodynamic stability. Consequently, much consideration has been given to when to start these interventions, i.e., medical boards in various countries generally advise against these measures in the acute phase especially in critical patients . Neverth2/FiO2 < 300 or a low Glasgow Coma Scale level, a progressive introduction of passive mobilization exercises and frequent position changes against gravity should be attempted to prevent deconditioning. Clinical parameters  should be thoroughly monitored. Criteria for interrupting the therapy include a respiratory rate >40 or <5 breaths/min, SpO2 < 88%, systolic blood pressure >200 or <90, diastolic blood pressure >110 or <60, heart rate >110 or <40, instauration of arrhythmias or angor pectoris, peripheral circulation deficits, agitation and neurological impairment [A recent scientific statement emphasized the importance of gradually starting rehabilitation therapy for patients affected by COVID-19 to avoid acute hypoxemia . In patipairment . Routines including limb mobilization are essential to avoid side effects on the musculoskeletal system  especially for those patients after a prolonged pronation passive mobilization therapy following ARDS . A few iWhen clinical improvement is attained, a progressive resistance training  performed with resistance bands and free weights of body weight in the post-acute phase can be considered as a safe intervention for the elderly. Active mobilization , accompanied by progressive muscular strengthening should be considered whenever the clinical situation allows it .The use of electrical stimulation is an emerging strategy of intervention with positive effects in seriously ill hospitalized patients who are unable to perform resistance exercises. The effectiveness of this therapy has been evidenced in immobilized patients after a spinal cord injury, congestive heart failure and chronic obstructive lung disease . In a reDespite the apparent safety of electrical stimulations in the initial stages of treatment, it is highly important to develop effective protocols of interventions for hospitalized elders that can be combined with either dynamic mobilization or functional strength exercises.The benefits of thermotherapy interventions have been previously evidenced in animal, in vitro and human studies. The application of heat on the whole body contributes to muscle recovery attenuating cellular damage and protein degradation . MoreoveThe novel scenario of COVID-19 and the constellation of the explained features should alert healthcare professionals to the possibility of an accelerated decline on physical function among the elderly. The use of concomitant interventions might be one of the major challenges for healthcare providers in order to ameliorate the functional decline of elderly patients, enhancing their recovery process and improving global survival rates. The long-term consequences and sequelae of COVID-19 are still unclear. The interest in long-term outcomes after recovery from SARS-CoV and MERS-CoV global epidemics has increased over the last years. Clinical investigations have reported that in the following months after SARS-CoV discharge, elderly patients experienced a significant functional decline, reduced musculoskeletal fitness, poor cardiorespiratory fitness and a lower quality of life than control subjects (shortly after discharge and at 24 months follow-up) ,69. WhilInterestingly, it has been observed in clinical practice that after overcoming COVID-19 disease, both in ambulatory care and hospital settings, a vast number of elderly patients have reported prolonged general weakness and muscular fatigue for several days and weeks. This is especially noticeable in ICU survivors as they encounter a significant loss of muscle thickness and appreciable motor incoordination . SpecialSurvivors after prolonged hospitalization and ICU stays generally sustain some degree of functional disability even years after the initial insult . Motor dUsually, a longer period of immobilization comes with a greater functional loss and slower rehabilitation after discharge. Moreover, the length of stay has been shown to have a positive correlation with a risk of falls and injuries . FurtherThese long-term consequences are expected to come at a significant additional cost with increased nursing home admission and hospital readmissions. Costs derived from pharmacotherapy, medical complications management and neuropsychological outcomes should be considered . In relaOlder people diagnosed with a COVID-19 infection are at a higher risk of severe muscle weakness and atrophy that may have negative consequences on functional disability.Therefore, it is extremely important to: (1) determine which potential pharmacological interventions have a negative impact on muscle quality and quantity; (2) define a feasible and reliable pharmacological protocol to achieve a balance between desired and undesired medication effects in the treatment of this novel disease; (3) implement practical strategies to reduce muscle weakness during bed rest hospitalization and (4) develop a specific, early and safe protocol-based care of functional interventions for older adults affected by COVID-19 during and after hospitalization.


The biofabrication of biomimetic scaffolds for tissue engineering applications is a field in continuous expansion. Of particular interest, nanofibrous scaffolds can mimic the mechanical and structural properties  of the natural extracellular matrix (ECM) and have shown high potential in tissue engineering and regenerative medicine. This review presents a general overview on nanofiber fabrication, with a specific focus on the design and application of electrospun nanofibrous scaffolds for vascular regeneration. The main nanofiber fabrication approaches, including self-assembly, thermally induced phase separation, and electrospinning are described. We also address nanofibrous scaffold design, including nanofiber structuring and surface functionalization, to improve scaffolds’ properties. Scaffolds for vascular regeneration with enhanced functional properties, given by providing cells with structural or bioactive cues, are discussed. Finally, current in vivo evaluation strategies of these nanofibrous scaffolds are introduced as the final step, before their potential application in clinical vascular tissue engineering can be further assessed.  Tissue engineering, which combines the principles and methods of the life sciences with those of engineering to create tissue replacements to direct tissue regeneration, has attracted many researchers with the hope of regenerating a patient’s own tissues and organs without the need for tissue/organ transplantation ,2. The mThe field of regenerative medicine has achieved significant progress in the past decade  4]. A f. A f4]. However, significant challenges remain before the widespread adoption of tissue engineering approaches in the clinic. Several important aspects should be considered for successful regeneration, such as (i) scaffold design with desired mechanical, chemical, and biological properties that better mimic a tissue’s native microenvironment and better support cell activity; (ii) maintenance and regulation of growth factors to steer cellular behavior; and (iii) vascularization, allowing integration of the engineered tissues into the host system for fully functional regeneration ,18. Tissue engineering approaches typically start with scaffold design. An engineered scaffold should provide favorable biochemical  and bioSelf-assembly is a method by which simple molecular and macromolecular building blocks are engineered to organize themselves through non-covalent forces, such as hydrogen bonding, hydrophobic forces, and electrostatic interactions ,42. The Supramolecular nanofibers can also be created by other self-assembling motifs. An early example of supramolecular polymers forming nanofibers is ureido-pyrimidone (Upy). Sijbesma and coworkers prepared the self-assembled UPy nanofibers through self-complementary four-hydrogen bonding between self-complimentary Upy moieties . The fibThe nanofibers produced by molecular self-assembly usually are much smaller than those produced by electrospinning, clearly due to the molecular design character of self-assembly . While fThermally induced phase separation (TIPS) has been used to produce three-dimensional (3D) porous scaffolds since the 1980s. Nanofibrous materials have also been made by this technique . When phL-lactic acid) (PLLA) nanofibrous matrices by using TIPS with a low polymer concentration from 1% to 7.5% in tetrahydrofuran . B. B91]. BThe shapes and morphologies of beads and fibers can be controlled by adjusting electrospinning parameters. For example, Lee et al. illustrated that changing polymer concentration during electrospinning could result in different bead dimensions and morphology. Bead structures were largely produced when electrospinning with a PS solution below 15%, while only fibers were formed after increasing the concentration above 15% . As PS iAligned nanofibers provide specific physical cues able to directly influence cell activity, especially by guiding cell distribution and elongation in the direction of the fibers . SeveralMoreover, aligned fibers also showed a positive effect on vascular regeneration. Zhu et al. fabricated PCL aligned fibers by using a rotating mandrel to collect fibers . Human uThe most common and effective way to fabricate aligned electrospun nanofibers is the use of a rotating collector B. A geneA honeycomb is composed of hexagonal wax cells constructed by honeybees in their nests . The natTo fabricate honeycomb patterns by electrospinning, two methods have proven successful: (1) self-assembly  and (2) In addition to honeycomb patterns, other studies reported achieving fiber patterns through directed fiber deposition, such as in the case of the direct writing approach ,121. LeeA conventional electrospun membrane only produces one type of (micro or nano) fiber. An improvement of recent electrospinning approaches is creating complex electrospun scaffolds with both micro and nanofibers at the same time. Electrospun fibers in the nano scale could mimic native ECM fibers (a diameter in the range of 10–50 nm), while microfibers create highly porous scaffolds which benefit cell infiltration and migration. The fabrication of electrospun scaffolds that contain spider-web-like nano-nets with two types of (micro or nano) fibers could enhance scaffolds properties for tissue engineering applications  and coulNylon-6 and poly (acrylic acid) nano-nets were first reported, which were fabricated by tuning electrospun parameters . Four yeDual air jet spinning (AJS) is another strategy with which to fabricate composite electrospun fibers with different diameters. The use of dual AJS could simultaneously control the mixing of two different polymers fibers from two AJS nozzles. This platform could afford the possibility of mixing two polymers together to produce web-like fibers with different diameters. Abdal-hay et al. reported that composite fibrous scaffolds composed of PCL and polyamide-6 (PA-6) fibers were successfully fabricated by using the dual AJS technique. Fiber diameter distribution showed that the diameters of PA-6 fibers were 278 ± 54 nm, while pure PCL had thick fibers with diameters of 2345 ± 152 nm. The composite fibrous scaffolds had better tensile properties than pure fibrous scaffolds. In vitro study demonstrated the PCL/PA-6 composite fibrous scaffolds provide a favorable microenvironment that supports attachment and proliferation of endothelial cells, so they could be promising scaffolds for vascular tissue engineering. Other studies have also shown spider-web-like structures in different electrospun polymeric membranes can better mimic the ECM and displayed enhanced mechanical properties, as in the cases here discussed. These scaffolds could be especially beneficial for cell attachment and migration in comparison to membranes without nano-webs ,128,129.D-threonine (Thr) and sodium hydroxide (NaOH) could self-assemble into helical nanofibers [2 nanofibers using that technique, with diameters of the fabricated nanofibers from 80 to 140 nm [4 flow in the carrier gas resulted in a helical structure of the formed nanofibers, the actual mechanism with which a helical structure was formed was not reported. The researchers hypothesized that CH4 helped with moderating the highly oxidizing environment and retained the activity of iron-catalyzed particles. Inspired by the structures of proteins in different tissues of our body, nanofibers with curved morphologies display many specific features, including large porosity, elasticity, and toughness, which make it attractive in biomedical tissue engineering. Three techniques has been reported to produce waved nanofibers: (1) self-assembly ,131, (2)nofibers . Peptideo 140 nm . AlthougElectrospinning has been regarded as the most common and efficient technique with which to fabricate helical nanofibers. Researchers produced helical nanofibers by electrospinning and studied the potential factors that could guide the fibers to be helical and curly. Zhou et al. created wavy nanofibers through an airflow-electrospinning process . Airflow2⋅HCl) could form nanotubes at physiological pH via self-assembly methods. To test the delivery of these cationic dipeptide nanotubes in cells, fluorescein labeled single stranded DNA (ssDNA) was bound to the nanotubes by electrostatic interactions. After incubation with HeLa cells, the fluorescence showed that these nanotubes could enter cells and accumulate in the cytoplasm. Nanotubes are also promising for potential applications of gene and drug delivery. However, low yield is a significant limitation to produce nanotubes in a large scale. The template-directed approach has also been used to build nanotubes, since it is more direct and controllable compared to the self-assembly approach [Tubular nanostructures are widely used in tissue engineering, especially for drug delivery . Many apapproach ,144. HouCompared with self-assembly and template-directed approaches, coaxial electrospinning was proved to be the optimal approach for creating continuous nanotubes, with controllable conditions and large-scale production. In co-electrospinning, a coaxial nozzle is the key device that is comprised of a central tube and a concentric circular corona. This coaxial nozzle allows two different solutions to produce a core-shell composite structure ,146. In Currently, nanofibers with different patterns have been successfully fabricated by adjusting the processing parameters of electrospinning. Nanofibers could be designed as specific structures depending on the biomedical applications, due to every structure having its own advantages. For example, aligned fibers were used to better mimic the collagen fibers in bone matrix . HoneycoTo explore more applications of nanofibrous scaffolds in tissue engineering, researchers investigated the functionalization of nanofibrous scaffolds by many different approaches, such as physical blends, core-shell electrospinning, and post functionalization . PhysicaUsing polymer blends is an easy and direct method to introduce bioactive components into nanofibrous scaffolds for tissue-engineering applications. Nanostructure polymer blends could result in the production of low-cost scaffolds with specific functionality. Biopolymers can be blended into a synthetic polymer for electrospinning to obtain better mechanical properties, good biodegradability, and good biocompatibility of nanofibers. For example, to improve the biodegradability and biocompatibility, gelatin was mixed into a PCL electrospun solution and then incorporated into PCL nanofibrous scaffolds during electrospinning . The obtThe combination of natural and synthetic polymers could effectively improve the mechanical properties and biocompatibility of nanofibrous scaffolds, which could support cell growth and favor tissue regeneration. More importantly, the simple physical blending process for the introduction of functional components to polymeric nanofibers usually resulted in converting the nanofibers into highly effective delivery systems. Many biofunctional components  . They fa2, O2, and NH3 have been used during plasma treatment to change the chemical composition or introduce functional groups on the surfaces of scaffolds for further applications. For example, polymer nanofibers were exposed with oxygen plasma in order to obtain carboxyl groups on the surface of nanofibers [2, –OH, and –COOH) on the surfaces of nanofibers, these surfaces could be largely used as substrates for biomolecule immobilization. Simple plasma treatment is a widely used method to improve nanofiber biocompatibility. Different gases such as Ar, Nnofibers . Plasma nofibers . After gA study demonstrated the functionalization of PLLA nanofibers with RGD (Arg–Gly–Asp) peptides by plasma treatments and covalent coupling. The plasma treatment of PLLA nanofibers is a key step to producing carboxyl groups for RGD coupling. RGD peptides could immobilize on the functionalized nanofibers by 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxy succinimide (EDC/NHS) chemistry. In vitro results showed that RGD functionalized scaffolds promoted the proliferation and osteogenic differentiation of hMSCs . AnotherThe surface modification of nanofibrous scaffolds could also be achieved by wet chemical treatments. Wet chemical approaches, such as hydrolysis, and soaking in NaOH or KOH, often lead to the degradation of nanofiber properties and morphology. Chen et al. reported that PCL nanofibrous membranes treated with NaOH etching led to enhanced roughness and surface area . 3T3 fibClick chemistry is an attractive alternative for facile immobilization of bioactive components onto electrospun nanofiber surface, because of its simple reaction conditions, high reaction rate, high yields, and functional group tolerance ,192,193.The surface graft approach has been also developed to introduce functional groups on scaffolds for the subsequent coupling of bioactive components. Plasma treatment is usually required to introduce free radicals for polymerization during graft polymerization. For example, the surface of poly(vinylidene) fluoride nanofibers was successfully grafted with poly(methyl methacrylate) by plasma-induced graft copolymerization . By procVascular regeneration is one of the most challenging issues in tissue engineering ,206. DurNanotopography has been noted as an important factor with which to affect cell growth and differentiation. ECs could interact with their physical environments and be guided by a scaffold’s topography. Xu et al. reported that the alignment of nanofibers plays a positive role in the regulation of endothelial cellular behavior . Cell elApart from electrospun scaffolds, a few other studies showed that EC morphogenesis into capillary-like structures was regulated by micropatterned stripe substrates ,223. DikMany researchers have reported that the controlled release of angiogenic factors could promote vascular formation in vitro and in vivo. Electrospun nanofibrous scaffolds show potential to incorporate or functionalize bioactive components onto the scaffolds, and scaffolds designed for drug release have shown controlled delivery. VEGF is the most important growth factor to stimulate early vascular formation and promote angiogenesis. Jia and his colleagues loaded VEGF into the inner of core/shell fibrous scaffold by coaxial electrospinning with PLGA as the shell . VEGF reMany studies have also reported the immobilization of VEGF-mimetic peptides on scaffolds as a potential solution for vascular regeneration. D’Andrea et al. designed a VEGF-mimetic peptide, QK (domain: KLTWQELYQLKYKGI), and showed the ability to activate VEGF receptors and similar bioactivity to VEGF . QK pept2 to generate electrospun scaffolds with a functionalizable amine [Apart from VEGF-memetic peptides, RGD peptide was also reported to immobilize into electrospun scaffolds for vascular tissue engineering. For example, Kim et al electrospun a mixture of PLGA and PLGA-b-PEG-NHle amine . RGD was2S), a unique gasotransmitter that has been recognized as an important physiological and pathological signaling molecule, can mediate and promote the effects on angiogenesis [2S promotes EC proliferation and migration has been reported by different groups [2S has been reported to simulate angiogenesis in vitro and in vivo [2S has been recognized to be beneficial for angiogenesis, researchers started to focus on the development of H2S releasing scaffolds for vascular regeneration [2S donor, with PCL solution to form H2S release fibrous scaffolds [2S fibrous scaffolds could facilitate (H9c2 and 3T3) cell proliferation. Moreover, these scaffolds were also reported to increase the expression of collagen type I and collagen type III, and wound healing related genes. Kang and his colleagues synthesized a pH-controlled H2S donor (JK-1) from phenylphosphonothioic dichloride [2S releasing electrospun nanofibers [2S release. JK1 doped PCL fibers were nontoxic to fibroblasts and in vivo experiments proved that PCL-JK1 could significantly improve wound healing. Although previous studies showed promising results in vitro and in vivo, many aspects still need to be improved for the fabrication of H2S releasing nanofibrous scaffolds: (1) a slow H2S-releasing donor needs to be included; (2) in addition to physical doping, other surface functionalization approaches should be considered. Hydrogen sulfide  assay and rabbit or rat corneas are the most widely used animal models for studying the process of angiogenesis in vivo. CAM is an extraembryonic membrane mediating gas and nutrient exchanges until hatching . Since tin vitro. For a more thorough review on the several angiogenesis available assays, the reader is referred elsewhere [CAM assay has been used by many researchers as an in vivo model in vascular tissue engineering for more than 40 years. A number of studies have evaluated electrospun nanofibrous scaffolds on the CAM to examine their angiogenic response and biocompatibility. The general procedure of CAM assay is shown in lsewhere . Scaffolds for tissue engineering have become more and more important in regenerative medicine, which is crucial for the development of advanced clinical therapy for those critical tissue injuries that do not heal correctly by themselves . The key(1) Structure design.Most tissue regeneration, such as that of bone, muscle, and cartilage, necessitates 3D scaffolds, but nanofibrous scaffolds with high thickness are difficult to obtain by electrospinning. Electrospinning normally produces 2D random nanofibrous scaffolds with high porosity in the height of few microns . Honeyco(2) Nanofiber functionalizationTraditional nanofiber functionalization approaches lack of selective control. Ideally, functionalization could also be provided in specific locations in 3D scaffolds through the presence of selective reactive groups. For example, this could be reached by photopatterning and would allow for achieving spatial control of the fiber functionalization. The ability to use a photopatterning approach to create any spatial functionalization of fibrous scaffolds is a significant advantage, which could be used for the partial functionalization of bioactive molecules on fibrous scaffolds for vascular tissue regeneration. (3) Vascular tissue regenerationAn ideal scaffold should not only provide an appropriate physical environment ,253, whi


Cardiac rhythm disorders are common in many patients with cancer. The management of synchronous long-standing persistent atrial fibrillation and pulmonary lesions remains a serious surgical dilemma due to the lack of clinical data and surgical guidelines. To the best of our knowledge, this is the first described case of simultaneous thoracoscopic pulmonary segmentectomy and left atrial posterior wall and pulmonary vein isolation combined with left atrial appendage resection in a patient with early-stage primary lung cancer and long-standing persistent atrial fibrillation. Coexisting malignancies and long-standing persistent atrial fibrillation (LSPAF) requiring treatment with radiofrequency ablation are not rare in clinical practice. We herein report a minimally invasive approach involving a combination of thoracoscopic left atrial posterior wall and pulmonary vein isolation with left atrial appendage resection and thoracoscopic segmental resection of right S6 for simultaneous treatment of atrial fibrillation and lung cancer. As far as we know, this is the first described case of simultaneous thoracoscopic approach to treat a patient with LSPAF and primary lung cancer.A 65-year-old woman with a history of LSPAF (> 15 years) was referred for thoracoscopic left atrial posterior wall and pulmonary vein isolation combined with left atrial appendage resection. After being treated with amiodarone, digoxin, and beta-blockers for several years, her electrocardiogram remained abnormal. Electrical cardioversions eight and six years before the admission were unsuccessful. Anticoagulant (Rivaroxaban) use was stopped after intestinal bleeding two years before the surgery.Brain natriuretic peptide on admission was elevated to 1621 pg/mL, while troponin I was negative. Echocardiography showed moderate mitral and tricuspid regurgitation, pulmonary hypertension , moderate impairment of left ventricular systolic motion, a left ventricular ejection fraction of 50%, and atrial dilatation, with a left atrial diameter of 43 mm. Coronary angiography showed arteries without any sign of obstructive atherosclerosis. Preoperative chest computed tomography (CT) is a part of the protocol for patients undergoing video-assisted thoracoscopic procedures at our institution and it revealed a mass in the superior segment (S6) of the inferior lobe of the right lung .-3.In order to follow the institutional protocol for cancer patients and minimize the operative trauma, we performed a totally thoracoscopic resection of the lung lesion and left atrial posterior wall and pulmonary vein isolation. Catheter ablation of atrial fibrillation was not performed because of its controversial efficacy in patients with LSPAFThe operation was carried out under general anesthesia with single lung ventilation. The patient was positioned supine with 45° rotation toward the left decubitus position. External pads for emergency defibrillation were placed on the chest wall. The surgeon stood in the right side of the patient to perform segmentectomy first.th intercostal space (ICS) on the scapular line, a 2-cm incision on the middle axillary line in the 4th ICS, and a 2-cm incision in the 5th ICS on the anterior axillary line for resection of the superior segment of the right inferior pulmonary lobe using a thoracoscopic linear stapler . The tumor had dark grey appearance and was completely included in the S6. The diagnosis of the lesion was confirmed by intraoperative frozen section.Three ports were made, including a 1-cm thoracoscopic port in the 6). At our institution, the modified GALAXY procedure is routinely used. We increased the number of ablations to 20 for each side  with frequent position changing of the device and change of device angulation after 10 ablations (technique described below).After that, the patient was positioned in supine position on the table to perform left atrial posterior wall and pulmonary vein isolation combined with left atrial appendage resection .After the surgery, the patient was transferred to the intensive care unit and recovered well. Sinus rhythm was restored 12 hours later, after amiodarone infusion and electrical cardioversion.th postoperative day.A perioperative red blood cell transfusion was not necessary. The patient’s postoperative mechanical ventilation time was 12 hours. Postoperative transthoracic echocardiography showed normal ejection fraction and heart chamber. Pathologic examination of the lung lesion showed a well differentiated primary pulmonary mucinous adenocarcinoma. Patient was discharged on the 6Three-month, 6-month, and 1-year follow-ups (24-hour Holter monitoring) revealed no sign of recurrence of atrial fibrillation or other supraventricular arrhythmia.Postoperative therapy included amiodarone, warfarin (canceled after three months), and bisoprolol (the only medicine continued in this patient after the 3-month follow-up).Chest CT at 3-month and 1-year follow-ups showed no sign of tumor recurrence and good expansion of the residual right lower lobe with no consolidation. No chemotherapy or radiotherapy was needed.. When compared with thoracoscopic lobectomy, thoracoscopic segmentectomy had similar rates of morbidity, recurrence, and survival. When compared with open segmentectomy, thoracoscopic segmentectomy was found to have equivalent oncologic results, with shorter hospital length of stay, reduced rates of morbidity, and lower cost. It was also found that thoracoscopic segmentectomy results in greater preservation of lung function and exercise capacity than the thoracoscopic lobectomy.Thoracoscopic pulmonary segmentectomy is feasible and safe in selected patients with small tumorsConcomitant cardiac rhythm disorders and lung cancer are not uncommon and may pose a serious surgical dilemma. No formal consensus regarding the optimal treatment of patients with early-stage lung cancer and atrial fibrillation, whether by contemporary or staged surgical treatment, has been reached. Cancer resection followed by atrial fibrillation treatment may increase the perioperative and intraoperative cardiogenic risks to the patient, while atrial fibrillation radiofrequency ablation followed by cancer resection is associated with a risk of intraoperative carcinoma metastasis. Combined one-stage cancer resection and Cox-Maze IV procedure may be associated with a high risk of surgical trauma to the patient. A one-stage, minimally invasive combined surgical procedure provides a new option for these patients. The advantages of a one-stage approach include use of fewer anesthetic agents, less operative stress and pain, a shorter hospital stay, lower therapeutic cost, and less delay of tumor treatment. Totally thoracoscopic left atrial posterior wall and pulmonary vein isolation combined with left atrial appendage resection has become a routine operation in clinical practice. In the present case, the combination of thoracoscopic left atrial posterior wall and pulmonary vein isolation and resection of the primary lung lesion had excellent short-term and long-term results.


We reconstructed 39 near-complete bacterial genomes harboring gcd, which represented diverse novel phosphate-solubilizing microbial taxa. Strong correlations were found between the relative abundance of these genomes and bioavailable soil P, suggesting their contributions to the enhancement of soil P cycling. Moreover, 84 mobile genetic elements were detected in the scaffolds containing gcd in the 39 genomes, providing evidence for the role of phage-related horizontal gene transfer in assisting soil microbes to acquire new metabolic potential related to P cycling.Little is known about the changes in soil microbial phosphorus (P) cycling potential during terrestrial ecosystem management and restoration, although much research aims to enhance soil P cycling. Here, we used metagenomic sequencing to analyse 18 soil microbial communities at a P-deficient degraded mine site in southern China where ecological restoration was implemented using two soil ameliorants and eight plant species. Our results show that the relative abundances of key genes governing soil microbial P-cycling potential were higher at the restored site than at the unrestored site, indicating enhancement of soil P cycling following restoration. The  Phosphorus (P) has long been considered the second most limiting nutrient for plant growth in terrestrial ecosystems after nitrogen (N) , 2. In cHeavily degraded ecosystems, such as abandoned mined lands, are characterized by extremely low levels of soil nutrients, including P –12. RestolpA), alkaline phosphatase (phoD), phytase (appA), phosphonatase (phnX), and C-P lyase (phnJ), are able to release free orthophosphate from recalcitrant organic P forms ..25].gcd, phoD, and phoA) were found in a higher abundance in ALRT than in UT and ULRT  in the degraded land, supporting our hypothesis regarding its predominance. Second, the relative abundance of gcd was 183 and 289 times higher in ALRT than in UT on the two sampling dates, respectively  in ULRT were comparable with or higher than those in ALRT  were found to harbor greater than five gcd genes individually  involved in organic P mineralization than the other six genomes  and bioavailable  P in soil . Remarkably, all five genomes belonged to genera without previously identified phosphate-solubilizing isolates  does not necessarily reflect the actual activity of the soil enzymes responsible for soil P cycling , we founand Fig. . There ales Fig. , while tGiven that the known enzymes responsible for the microbial solubilization of recalcitrant soil P are encoded by a small number of genes , 19, thegcd-containing genome bins obtained in this study greatly expand the known diversity of phosphate-solubilizing microbes. As recently summarized [gcd-containing genome bins represented members of four other phyla . The authors further ascribed their findings to HGT that was putatively driven by P limitation, though their opinion was later thought to be dubious [gcd genes in some of the genome bins [gcd genes but lacked the mobile genetic elements involved in HGT  from phyla that were not previously known to have isolates capable of solubilizing phosphate play an important role in driving the enhancement of soil P cycling following the restoration of a heavily degraded mined land. Furthermore, phage-related HGT is likely involved in the acquisition of gcd in some of these bacteria. Our findings may have important implications for understanding the microbial mechanisms underlying soil P cycling in many other terrestrial ecosystems, given that gcd has been reported to prevail in various types of soils [We conclude that certain phosphate-solubilizing bacteria (as indicated by the occurrence of the of soils –27.Supporting information


Angiogenesis, the formation of new blood vessels from preexisting one, represents a critical process for oxygen and nutrient supply to proliferating cells, therefore promoting tumor growth and metastasis. The Vascular Endothelial Growth Factor (VEGF) pathway is one of the key mediators of angiogenesis in cancer. Therefore, several therapies including monoclonal antibodies or tyrosine kinase inhibitors target this axis. Although preclinical studies demonstrated strong antitumor activity, clinical studies were disappointing. Antiangiogenic drugs, used to treat metastatic patients suffering of different types of cancers, prolonged survival to different extents but are not curative. In this review, we focused on different mechanisms involved in resistance to antiangiogenic therapies from early stage resistance involving mainly tumor cells to late stages related to the adaptation of the microenvironment. Angiogenesis is the formation of new blood vessels from pre-existing ones . It is aOne of the first relationships between angiogenesis and cancer was introduced 55 years ago when ®), a humanized anti-VEGFA monoclonal antibody (®), sunitinib (Sutent®), everolimus (Afinitor®), temsirolimus (Torisel®), have for instance been extensively studied in several metastatic cancers , vandetanib (Caprelsa®) or lenvatinib (Lenvima®)  . LenvatiSeveral tumor cells aberrantly expressed VEGFRs and exhibit exacerbated genetic plasticity following anti-angiogenic therapies that is highlighted by several mechanisms of adaptation/resistance. The crosstalk between tumor and stromal cells allows escape mechanisms counteracting the effects of anti-angiogenic therapies.The objective of this review is to present an overview of the different resistance mechanisms to angiogenic therapies, from the earliest to the late ones, including tumor and stromal cells adaptation. The different mechanisms were divided into “immediate early” resistance mainly reffering to adaptation of tumor cells following exposure to the drug for few minutes/hours; into “early” resistance reffering to days/weeks after treatment exposure and into “late” one occuring several months/years after the treatment and depending on metastasis . UnderstAngiogenic redundancy is one of the earliest mechanisms leading to refractoriness or acquired resistance to anti-angiogenic therapies mainly targeting VEGFA and its receptors. Although VEGFA is the best known angiostimulatory protein, angiogenesis can be triggered by several growth factors including angiopoietins (ANGs), epidermal growth factor (EGFs), fibroblast growth factors (FGFs), hepatocyte growth factor (HGF), transforming growth factors (TGFs), placental growth factor (PlGF) or stromal cell-derived factor 1 (SDF1) . Except ®, a tyrosine kinase inhibitor of the VEGFR1, VEGFR2 and VEGFR3 , expressed on tumor and stromal cells including endothelial cells, cancer-associated-fibroblasts or myeloid cells infiltrating tumors . The FGFThe proangiogenic role of FGF and its involvement in resistance to VEGFA inhibitors constitute a strong rationale for the development of inhibitors targeting the FGF and VEGFA pathways. The combined inhibition of FGF2 and VEGFA was highly efficient in preclinical models of head and neck carcinoma or pancreatic tumors . FGFR inIn the 1970’s several groups demonstrated the existence of growth factors for fibroblasts and smooth muscle cells derived from platelets . These fBased on the redundancy in angiogenic pathways, limited benefits to patients were observed by targeting a single angiogenic growth factor or its receptor. This redundancy is at the origin of innate or acquired resistance, by activation of alternative proliferation/survival pathways. Inhibition of ANG2-, FGF- or PlGF-mediated signaling pathways with those of VEGFA overcomes aspects of resistance to VEGFA blockade, but a sustained inhibition remains to be demonstrated.The Transforming Growth factor-β (TGF-β) family regulates cell proliferation, differentiation and apoptosis . In tumo®) an inhibitor of VEGFR but also of cMET and AXL to actors involved in relapses after sunitinib treatment. Cabozantinib was approved as a second line treatment for RCC patient experiencing progression on sunitinib , events occurring later as discussed above  into H+ and bicarbonate (HCO3–) which is rapidly uptaken into cell by Na+-HCO3– transporters sustaining alkaline pHi compatible with cell survival  play a key role in angiogenesis and in tumor progression . MMPs caTumors are a complex association of cancer cells as well as a stromal compartment with cellular and noncellular components. Tumor stroma plays crucial roles in tumor progression and in resistance to treatments. The dense tumor stroma can limit the access of therapeutic agents to their target due to fibrosis, high interstitial pressure and degradation of drugs by stromal enzymes . The rigCells constituting the tumor environment play a key role in the resistance to angiogenesis inhibitors, especially cancer-associated fibroblasts (CAFs) and pericytes.Cancer-associated fibroblasts are the principal component of the stroma within the tumor microenvironment. They exhibit diverse functions including matrix remodeling, crosstalk with tumor, endothelial or immune cells, promoting tumorigenesis. CAFs notably allow the recruitment of endothelial progenitors cells (EPCs) and bone-marrow-derived cells (BMDCs) through SDF1 expression and stimulation of its receptor CXCR4 on EPCs . The rol125I-radiolabeled antibody resulted in the inhibition of HCC tumor growth and decreased angiogenesis (®), which inhibits VEGFRs has a potent anti-angiogenic effect and inhibits also FGF receptors involved in anti-angiogenic resistance. It is now used in the therapeutic arsenal against kidney tumors  . Infiltr+ Gr1+ cells are composed of a mixed population including neutrophils, macrophages and dendritic cells displaying immunosuppressive and pro-tumorigenic capacities (Myeloid-derived suppressor cells (MDSCs), also known as CD11bpacities . Preclinpacities . The infpacities . Indeed,pacities . The prepacities . Upregulpacities , b. Morepacities . In agrepacities .Among the MDSCs population, increased tumor-infiltration by neutrophils promote resistance to bevacizumab. Neutrophils induce Bv8-dependent tumor angiogenesis independently from the VEGFA signaling. Preclinical studies demonstrated that blockade of Bv8 decreases the recruitment of MDSC and angiogenesis .Macrophages, specialized phagocytic cells, also display plasticity and shape their phenotype in response to environmental conditions, making them a relevant candidate for treatment resistance . The firThese results suggest that BMDCs are therapeutic targets for counteracting tumor refractoriness to anti-angiogenic therapies. Inhibition of the SDF1 pathway notably prevents BMDCs tumor infiltration and overcomes such resistance . EquivalThe discovery of endothelial progenitor cells (EPCs) in adults and their putative vascular-promoting properties has generated debate in the field of vascular biology . EPCs weHeterogeneity of tumor endothelial cells (TECs) contributes to resistance to anti-angiogenic therapy . TECs coThe hypoxic tumor microenvironment stimulates the expression of stemness genes in TECs, such as stem cell antigen 1 (Sca-1), MDR-1 and aldehyde lactate deshydrogenase (ALDH), leading to resistance to paclitaxel and to fluorouracil (5-FU) . The vasTransforming growth factors can originate from dedifferentiation of tumor cells, monocytes or from EPCs contributing to high heterogeneity and to resistance to anti-angiogenic treatments. Although cancer cells acquired drug resistance is well documented, the heterogeneity of TECs must be considered as a major actor. Recent single cell RNA-sequencing studies revealed endothelial cell heterogeneity following anti-VEGF therapy . TECs caAmong TECs-targeting therapies, inhibitors of CXCR4 were scrutinized since TECs are CXCR4-enriched populations is associated with a poor outcome in HCC. Inhibition of CXCR4 induces promising anti-tumor response mainly by preventing recruitment of BMDCs in the tumor mass and must be considered as a future therapeutic option .Metastatic dissemination of cancer cells relies on several parameters and notably on the bi-directional communication between primary tumor and future metastatic tissues. This crosstalk essentially involves the production of particles by cancer or stromal cells. These particles are known as Extracellular vesicles (EVs). EVs carry onco peptides, RNA species or lipids from donor to recipient cells, triggering phenotypic changes of the future pre-metastatic niches . EV stimRecently, the emergence of EVs as a novel player of drug resistance has gained interest. EVs transfer drugs from resistant to sensitive cells triggering cell resistance . VEGFA cMetastases can remain for months or years in a quiescent, dormant state, in the tissue they colonized. These micro-metastases constitute a residual disease characterized by the persistence of tumor cells, undetectable by conventional diagnostic techniques. The tumor dormancy can be defined as the lag in tumor growth occurring between primary tumor formation and the appearance of clinically detectable metastases . The preCancer stem cells (CSCs) constitute a small population of cells within tumor exhibiting abilities of self-renewal, differentiation and high tumorigenicity potential. They play a key role in the initiation of cancer and in the metastatic cascade. In 2003, CSCs were first identified in human breast and brain cancers . CSCs exTheir tumor initiating properties and their metastatic potential suggest that CSCs are involved in resistance to therapies. Conventional treatments including chemo- and radiation therapies generate the production of CSCs promoting tumor escape . CSCs arEpithelial-mesenchymal transition (EMT) defines the acquisition of characteristics of invasive mesenchymal cells by epithelial cells. EMT is implicated in tumor invasion and metastasis and correlates with poor clinical outcome in several solid tumors . During Several studies highlighted the role of the tyrosine kinase receptor c-MET in promoting tumor invasiveness and metastasis in response to anti-angiogenic therapies .Although sunitinib and anti-VEGFA decreased tumor volume, invasiveness, hypoxia and EMT markers are increased . In addiHistorically, lymphatic vessels were considered as passive participants in metastatic dissemination, only acting as channels for tumor cells transit. Nowadays, it becomes evident that lymphatic vessels have an active role in promoting metastasis. The first pro-lymphangiogenic factors identified more than 20 years ago were the VEGFC and VEGFD that bind to VEGFR3 expressed on lymphatic endothelial cells triggering lymphangiogenesis . Overexpvegfc gene transcription, mRNA stability and protein production and the subsequent VEGFC-dependent development of lymphatic vessels. Moreover, hypoxia upregulated VEGFC expression  intrinsic reprogramming of tumor cells with upregulation of alternative pro-angiogenic pathways, increased of lymphangiogenesis-related genes and processes and initiation of EMT (ii) conditioning the microenvironment, with the recruitment of local- and bone marrow-derived cells or used novel neovascularization modalities. All of these mechanisms lead to increased metastatic rate. Ten years ago, Increased metastasis rate following anti-angiogenic therapies are highly variable and depends on several parameters such as the type of treatment, the dose and the schedule. 2, the core of tumors become hypoxic and tumor cells counteract hypoxia by the production of angiogenic growth factors. Among them, VEGFA is one of the most important. Targeting the VEGFA/VEGFRs represented a great breakthrough in the therapeutic management of cancer patients. Unfortunately, complete responses are rare, and tumors counteract this inhibition through different processes. The molecular mechanisms of resistance are not fully understood and deciphering them has gained interest. It is now evident that several mechanisms exist. They involve a wide range of processes; (i) the earliest, with the upregulation of genes involved in angiogenic redundancy, EMT or the lysosomal sequestration of drugs, to the latest (ii) with an adaptation of the tumor microenvironment, reflected by the recruitment of progenitors cells, lymphangiogenesis, and adapted neovascularization modalities. All these mechanisms allow tumor metastasis and serve as limitations to anti-angiogenic drug efficacy.Angiogenesis processes, through the establishment of a new vascular network, are an important contributor to tumor development and metastatic dissemination. Once the tumor has reached 1-2 mmHence, combining treatments targeting tumor cells and cells of the tumor microenvironment should limit resistance and should improve patients’ survival. One of the first and of the obvious way of resistance involves angiogenic redundancy by multiple growth factors as suggested by the anti-tumoral effects of FGF inhibition and bevacizumab . AlthougAnother promising therapeutic strategy consists in targeting lymphangiogenesis and angiogenesis. Lymphangiogenesis induced by anti-angiogenesis dedicated compounds gives rise to node metastasis, leading at term to an increased metastatic rate and poor outcome in patients . MoreoveNevertheless, despite their effects on PFS and OS, these combinations are not curative. The development of animal models mimicking the tumor microenvironment as well as preclinical evaluations of combo therapies are urgently needed to improve patients PFS and OS. To reach the “Golden Age” of tumor treatment as defined by By destroying the vascular network, antiangiogenic therapies efficacy should have cause vascular network destruction leading to tumor cells asphyxia and nutrient starvation. Moreover, antiangiogenic treatments should have targeted only normal endothelial cells that cannot undergo genetic plasticity, a specific property of tumor cell adaptation to treatments. However, aberrant expression, by tumor cells, of receptors inhibited by antiangiogenic drugs stimulated the genetic adaptation of tumor cells mainly through epigenetic modifications. For example, EZH2 a specific histone methyl transferase is a driver of sunitinib resistance in kidney cancers . In addiThe correlation between the efficacy of antiangiogenic drugs and tumor grade was also a neglected parameter. Controversial results emerged from their efficacy in non-metastatic versus metastatic kidney cancers. Whereas they are the standard of cancer for metastatic tumors their efficacy as an adjuvant therapy gave conflicting results. The ASSURE trial (NCT00326898) showed no survival benefit relative to placebo whereas the S-TRAC trial showed that sunitinib in an adjuvant setting prolonged the disease free survival for more than 1 year . These cWith the advent of the immunotherapy, the blockage of angiogenesis should be reconsidered and the “blasting missil” must be discovered.It is now evident that targeting only one mechanism involved in cancer development is insufficient. The cancer Hallmarks described by Hanahan and Weimberg probably shape the future treatments to increase the percentage of complete remissions. What is the ideal strategy? Targeting at the same time different Hallmarks with already approved therapies or to find targets that drive concomitantly the different Hallmarks? If these targets exist, a specific inhibitor will serve as a “blasting missile” to destroy the tumor. The reality is probably an intermediate option.CM and GP are equally responsible for all parts of the manuscript. All authors contributed to the article and approved the submitted version.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.