Cyclopeptide moroidin inhibits vasculogenic mimicry formed by glioblastoma cells via regulating β-catenin activation and EMT pathways

Glioblastoma(GBM)is a highly vascularized malignant brain tumor with poor clinical outcomes.Vasculogenic mimicry(VM)formed by aggressive GBM cells is an alternative approach for tumor blood supply and contributes to the failure of anti-angiogenic therapy.To date,there is still a lack of effective drugs that target VM formation in GBM.In the present study,we evaluated the effects of the plant cyclopeptide moroidin on VM formed by GBM cells and investigated its underlying molecular mechanisms.Moroidin significantly suppressed cell migration,tube formation,and the expression levels ofα-smooth muscle actin and matrix metalloproteinase-9 in human GBM cell lines at sublethal concentrations.The RNA sequencing data suggested the involvement of the epithelialmesenchymal transition(EMT)pathway in the mechanism of moroidin.Exposure to moroidin led to a concentration-dependent decrease in the expression levels of the EMT markers N-cadherin and vimentin in GBM cells.Moreover,moroidin significantly reduced the level of phosphorylated extracellular signal-regulated protein kinase(p-ERK)and inhibited the activation of β-catenin.Finally,we demonstrated that the plant cyclopeptide moroidin inhibited VM formation by GBM cells through inhibiting the ERK/β-catenin-mediated EMT.Therefore,our study indicates a potential application of moroidin as an anti-VM agent in the treatment of GBM.

DPY19L3 promotes vasculogenicmimicry by its C-mannosyltransferase activity

C-mannosylation is a post-translational modification that occurs intracellularly in the endoplasmic reticulum.In humans,biosynthesis of C-mannosylation in proteins containing thrombospondin type 1 repeat is catalyzed by the DPY19 family;nonetheless,biological functions of protein C-mannosylation are not yet fully understood,especially in tumor progression.Vasculogenic mimicry(VM)is the formation of fluid-conducting channels by highly invasive and genetically deregulated tumor cells,enabling the tumors to form matrix-embedded vasculogenic structures,containing plasma and blood cells to meet the metabolic demands of rapidly growing tumors.In this study,we focused on DPY19L3,a C-mannosyltransferase,and aimed to unravel its role in VM.Knockout of DPY19L3 inhibited the formation of VM in HT1080 human fibrosarcoma cells.Re-expression of wild-type DPY19L3 recovered VM formation;however,DPY19L3 isoform2,an enzymatic activity-defect mutant,did not restore it,suggesting that the C-mannosyltransferase activity of DPY19L3 is crucial to its function.Furthermore,the knockdown of DPY19L3 in MDA-MB-231 breast cancer cells hindered its network formation ability.Altogether,our findings suggest that DPY19L3 is required for VM formation and stipulate the relevance of C-mannosylation in oncogenesis.

Vasculogenic mimicry:a pivotal mechanism contributing to drug resistance in antiangiogenic therapy

The growth of solid tumors relies on establishing a robust blood supply,with angiogenesis playing a key role in this intricate process.Based on this understanding,therapeutic strategies targeting tumor angiogenesis have been developed.However,the clinical effectiveness of antiangiogenic therapy(AAT)in treating tumors has not lived up to expectations.In recent years,vasculogenic mimicry(VM)has attracted increasing attention from the academic community as a longstanding but often overlooked mechanism of nonangiogenic tumor vascularization.Within the tumor microenvironment,neoplastic cells can autonomously form vessel-like structures,creating a blood supply that does not rely on endothelial cells.This phenomenon,known as VM,is a critical marker of aggressive tumors and may play a significant role in conferring resistance to AAT.In this review,we thoroughly examine the evidence,clinical characteristics,and mechanisms of VM across various tumor types and explore its potential role and importance in resistance to AAT and the development of new antitumor therapies.

沉默miR156表达的mimicry156载体的构建及转化烟草的研究

miR156在植物营养生长阶段幼年期向成年期的转变过程中发挥重要的调控作用,其通过降解SPLs基因m RNA和翻译抑制调控靶基因的表达。通过定向改造拟南芥内源性Target mimicry IPS1(INDUCED BY PHOSPHATE STARVATION 1)构建了抑制miR156表达的mimicry156载体,并转化获得转基因烟草植株,转基因植株mimicry156对内源性miR156具有抑制作用。该方法为研究miR156在植物营养生长阶段的调控作用提供了方便有效的途径。

Molecular regulation of vasculogenic mimicry in tumors and potential tumor-target therapy

"Vasculogenic mimicry(VM)",is a term that describes the unique ability of highly aggressive tumor cells to express a multipotent,stem cell-like phenotype,and form a pattern of vasculogenic-like networks in threedimensional culture.As an angiogenesis-independent pathway,VM and/or periodic acid-schiff-positive patterns are associated with poor prognosis in tumor patients.Moreover,VM is resistant to angiogenesis inhibitors.Here,we will review the advances in research on biochemical and molecular signaling pathways of VM in tumors and on potential anti-VM therapy strategy.

Expression of Maspin in Non-small Cell Lung Cancer and Its Relationship to Vasculogenic Mimicry

Maspin belongs to the serine protease inhibitor （serpin） family and has been proven to be a suppressor of tumor growth and metastasis in many types of tumors. The purpose of this study was to investigate the expression of maspin in non-small cell lung cancer （NSCLC） and its relationship to vasculogenic mimicry （VM）. A total of 160 specimens of NSCLC were involved in this study and 20 specimens of normal lung tissue served as controls. VM, microvessel density （MVD） and the expression of maspin were detected by using immunohistochemical staining. The results showed that the positive rates of maspin and VM in the NSCLC group were 48.1% （77/160） and 36.9% （59/160）, respectively, which were significantly different from those in the control group with the positive rates of maspin and VM being 100% and 0% respectively （P〈0.05）. VM, MVD and the expression level of maspin were significantly related to tumor differentiation, lymph node metastasis, clinical stages and postoperative survival time （all P〈0.05）. The maspin expression in patients with squamous cell carcinoma was significantly higher than that in those with adenocarcinoma （P〈0.05）. The maspin expression was negatively correlated with VM and MVD, and there was a positive correlation between VM and MVD. Maspin-negative expression, VM and high MVD score were negatively related to the 5-year-survival rate. PTNM stages, VM, MVD and maspin expression were independent prognostic factors for NSCLC （P〈0.05）. It was suggested that the loss of expression of maspin may participate in the invasion and metastasis of NSCLC and it has a positive relationship to VM in NSCLC. Combined detection of maspin, VM and MVD may help predict the progression and prognosis of NSCLC.

Cancer stem-like cells directly participate in vasculogenic mimicry channels in triple-negative breast cancer

Objective: Vasculogenic mimicry(VM) channels that are lined by tumor cells are a functional blood supply in malignant tumors.However, the role of VM-initiating cells remains poorly understood. Cancer stem-like cells(CSCs) are positively correlated with VM. In this study, triple-negative breast cancer(TNBC) enriched with CSCs was used to investigate the relationship between VM and CSCs.Methods: The expression of several CSC markers was detected by immunohistochemistry in 100 human breast cancer samples.The clinical significance of CSC markers and the relationship between VM, CSCs, breast cancer subtypes, and VM-associated proteins were analyzed. CD133+ and ALDH+ human and mouse TNBC cells were isolated by FACS to examine the ability of VM formation and the spatial relationship between VM and CSCs.Results: CSCs were associated with TNBC subtype and VM in human invasive breast cancer. CSCs in TNBC MDA-MB-231 cells formed more VM channels and expressed more molecules promoting VM than the non-TNBC MCF-7 cells in vitro. MDA-MB-231 cells that encircled VM channels on Matrigel expressed CD133. Moreover, CSCs were located near VM channels in the 3D reconstructed blood supply system in human TNBC grafts. The CD133+ and ALDH+ cells isolated from TA2 mouse breast cancer formed more VM channels in vivo.Conclusions: CSCs line VM channels directly. Additionally, CSCs provide more VM-related molecules to synergize VM formation. The signaling pathways that control CSC differentiation may also be potential treatment targets for TNBC.

Vasculogenic Mimicry and Aberrant Expression of HIF-lα/E-cad Are Associated with Worse Prognosis of Esophageal Squamous Cell Carcinoma

Summary： This study aims to find good markers for predicting the prognosis of patients with eso- phageal squamous cell carcinoma （ESCC）. Vasculogenic mimicry （VM） and the expression of hy- poxia inducible factor-1α（HIF-1α）/E-cad protein in ESCC were investigated by immunostaining. The association between VM, HIF-1α/E-cad and clinicopathologic characteristics and 5-year-survival rate of patients with ESCC was analyzed. A total of 160 ESCC specimens were involved in this study and 28 specimens of normal esophageal mucosa served as controls. VM channels were identified in 78 （48.75%） of the 160 ESCC specimens and none of the normal esophageal mucosa was found to have VM. The rates of high-expression of HIF-1αand E-cad in ESCC were 43.75% and 38.75%, while the rates in control were 17.86% and 71.43%, respectively （P〈0.05 for all）. VM and the expression levels of HIF-1α and E-cad were significantly related to lymph node metastasis, serosa infiltration, PTNM staging and 5-year-survival rates of patients with ESCC （P〈0.05 for all）. VM was positively corre- lated with HIF-1α but negatively with E-cad, and HIF-let was negatively correlated with E-cad （P〈0.001 for all）. The 5-year-survival rate of patients with ESCC was 6.41% （5/78） in VM group and 65% （52/82） in non-VM group, 7.14% （5/70） in high HIF-1α expression group and 57.78% （52/90） in low HIF-1α expression group. Oppositely, the 5-year-survival rate in high E-cad expression group was 80.65% （50/62） and that in low E-cad expression group was 7.37% （7/98） （P〈0.05 for all）. Cox multifactor regression analysis indicated that lymph node metastasis, PTNM stage, VM and expres- sion levels of HIF-1α and E-cad were independent risk factors of patients with ESCC （P〈0.05 for all）. Combined detection ofVM, HIF-1α and E-cad plays an important role in predicting the invasion, me- tastasis and prognosis of patients with ESCC.

Notch4 Inhibition Suppresses Invasion and Vasculogenic Mimicry Formation of Hepatocellular Carcinoma Cells

Vasculogenic mimicry（VM） is a process by which aggressive tumor cells generate non-endothelial cell-lined channels in malignant tumors including hepatocellular carcinoma（HCC）. It has provided new insights into tumor behavior and has surfaced as a potential target for drug therapy. The molecular events underlying the process of VM formation are still poorly understood. In this study, we attempted to elucidate the relationship between Notch4 and VM formation in HCC. An effective si RNA lentiviral vector targeting Notch4 was constructed and transfected into Bel7402, a HCC cell line. VM networks were observed with a microscope in a 3 dimensional cell culture system. Cell migration and invasion were evaluated using wound healing and transwell assays. Matrix metalloproteinases（MMPs） activity was detected by gelatin zymography. Furthermore, the role of Notch4 inhibition in Bel7402 cells in vivo was examined in subcutaneous xenograft tumor model of mice. The results showed that downregulation of Notch4 destroyed VM network formation and inhibited migration and invasion of tumor cells in vitro（P〈0.05）. In vivo, tumor growth was also inhibited in subcutaneous xenograft model（P〈0.05）. The potential mechanisms might be related with down-regulation of MT1-MMP, MMP-2, MMP-9 expression and inhibition of the activation of MMP2 and MMP9. These results indicated that Notch4 may play an important role in VM formation and tumor invasion in HCC. Related molecular pathways may be used as novel therapeutic targets for HCC antiangiogenesis therapy.

Dexmedetomidine Promotes Angiogenesis and Vasculogenic Mimicry in Human Hepatocellular Carcinoma through α^(2)-AR/HIF-1α/VEGFA Pathway

Objective Dexmedetomidine(DEX),the most specificα^(2)-adrenergic receptor agonist widely used for its sedative and analgesic properties,has been reported to upregulate HIF-1αexpression to protect hypoxic and ischemic tissues.However,it is largely unclear whether DEX can also upregulate Hypoxiainducible factor-1 alpha(HIF-1α)expression and its downstream vascular endothelial growth factor-A(VEGFA)in cancer tissues with oxygen-deficient tumor microenvironment.Methods We used SMMC-7721 cells,MHCC97-H cells,and a mouse model of orthotopic hepatic carcinoma to explore the effect of DEX on angiogenesis and vasculogenic mimicry(VM)and its mechanism.Under normoxic(20%O^(2))and hypoxic(1%O^(2))conditions,DEX was used to intervene cells,and yohimbine was used to rescue them.Results The results showed that DEX promoted angiogenesis and VM in human liver cancer cells within a certain dose range,and the addition of yohimbine inhibited this effect.DEX could activate HIF-1α/VEGFA pathway,which was further verified by silencing HIF-1α.Consistently,in vivo results also showed that DEX can up-regulate HIF-1α/VEGFA expression,and enhance the number of VM channels and microvessel density(MVD).Conclusion We believe that HIF-1α/VEGFA might be an important signaling pathway by which DEX promotes angiogenesis and VM formation in human hepatocellular carcinoma,whereasα^(2)-adrenergic receptor mediation might be the critical mechanisms.

The Effects of All-Trans Retinoic Acid on Vasculogenic Mimicry Formation Ability in CD133+ Glioma Stem Cells and Its Mechanisms

Objective: to investigate the effects of all-trans retinoic acid (ATRA) on vasculogenic mimicry formation in glioma stem cells. Methods: U87 stem cells were harvested through a suspension culture assay from the U87 cells, identified by CD133 and nestin, and counted by a flow cytometry. To investigate the VM formation ability of U87 stem cells with the treatment of various concentrations of ATRA, a Matrigel-based tube formation assay was used in the present study in vitro and tube-like structure (typical tube, TT;atypical tube AT) was observed and counted. Then the expressions of VEGF, VEGFR-2 and CD133 were measured throughout real time q-PCR, western blotting and immunofluorescence techniques. The data, presented as the mean ± standard deviation, were analyzed using SPSS software. One-way analysis of variance was used to compare groups and Fisher’s least significant difference tests were performed for subsequent comparisons between groups. P Results: Most of the harvested spheroid cells were positive for nestin and 88.4% were positive forCD133. The CD133+ U87 cells were cultured into tube like structure loaded on the top of Matrigel and the quantity of tubes was decreased under the treatment of ATRA. In addition, the expressions of VEGF, VEGFR-2 and CD133 were significantly reduced under the treatment of ATRA, particularly in the higher concentration groups (20 and 40 μmol, P Conclusions: ATRA may inhibit the establishment of VM differing from stem cells in glioma, and these effects may attribute to the effects of ATRA’s promotion of the differentiation of stem cells and/or down regulation of the expressions of proangiogenic factors VEGF and its receptor VEGFR-2. Thus, the results of the present study indicated a novel idea for the treatment of GBM and enriched the anti-glioma mechanisms of ARTA.

Molecular mimicry and multiple sclerosis

Multiple sclerosis （MS） is a chronic demyelinating disease of the central nervous system. Although the exact underlying mechanism leading to myelin destruction is unknown, the molecular mimicry theory is the most commonly acknowledged elucidation of MS pathology. Although various antigens have been associated with MS induction, this review presents studies focused on key bacterial and viral antigens that lead to the development of MS. The research specific to a molecular mimicry theory of MS via each implicated agent is weak; however, collectively the reports provide credible support for this theory. Given that homologous sequences are not required to lead to antigenic cross-reactivity, it is reasonable to conclude that certain viral and bacterial antigens with 5-10 similar amino acids in sequence can lead to self destruction of similar myelin sequences. Thus, this literature review has provided insight to further the understanding of the etiology of multiple sclerosis.

Downregulation of Astrocyte Elevated Gene-1 Expression Combined with All-Trans Retinoic Acid Inhibits Development of Vasculogenic Mimicry and Angiogenesis in Glioma

Objective This study aimed to investigate the effects of downregulating astrocyte elevated gene-1(AEG-1)expression combined with all-trans retinoic acid(ATRA)on vasculogenic mimicry(VM)formation and angiogenesis in glioma.Methods U87 glioma cells were transfected with AEG-1 shRNA lentiviral vectors(U87-siAEG-1)and incubated in a medium containing 20µmol/L ATRA.Matrigel-based tube formation assay was performed to evaluate VM formation,and the cell counting kit-8(CCK-8)assay was used to analyze the proliferation of glioma cells in vitro.Reverse transcription-quantitative polymerase chain reaction and Western blot analysis were used to investigate the mRNA and protein expression of related genes,respectively.Glioma xenograft models were generated via subcutaneous implantation of glioma cells in nude mice.Tumor-bearing mice received an intraperitoneal injection of ATRA(10 mg/kg per day).Immunohistochemistry was used to evaluate the expression of related genes and the microvessel density(MVD)in glioma xenograft models.CD34/periodic acid-Schiff double staining was performed to detect VM channels in vivo.The volume and weight of tumors were measured,and a tumor growth curve was drawn to evaluate tumor growth.Results A combination of ATRA intervention and downregulation of AEG-1 expression significantly inhibited the proliferation of glioma cells in vitro and glioma VM formation in vitro and in vivo.It also significantly decreased MVD and inhibited tumor growth.Further,the expression levels of matrix metalloproteinase(MMP)-2,MMP-9,vascular endothelial-cadherin(VE-cadherin),and vascular endothelial growth factor(VEGF)in glioma significantly decreased in vivo and in vivo.Conclusion Hence,a combinatorial approach might be effective in treating glioma through regulating MMP-2,MMP-9,VEGF,and VE-cadherin expression.

CircMAN1A2 promotes vasculogenic mimicry of nasopharyngeal carcinoma cells through upregulating ERBB2 via sponging miR-940

Nasopharyngeal carcinoma(NPC)is the most prevalent human primary malignancy of the head and neck,and the presence of vasculogenic mimicry(VM)renders anti-angiogenic therapy ineffective and poorly prognostic.However,the underlying mechanisms are unclear.In the present study,we used miR-940 silencing and overexpression for in vitro NPC cell EdU staining,wound healing assay and 3D cell culture assay,and in vivo xenograft mouse model and VM formation to assess miR-940 function.We found that ectopic miR-940 expression reduced NPC cell proliferation,migration and VM,as well as tumorigenesis in vivo.By bioinformatic analysis,circMAN1A2 was identified as a circRNA that binds to miR-940.Mechanistically,we confirmed that circMAN1A2 acts as a sponge for miR-940,impairs the inhibitory effect of miR-940 on target ERBB2,and then activates the PI3K/AKT/mTOR signaling pathway using RNA-FISH,dual luciferase reporter gene and rescue analysis assays.In addition,upregulation of ERBB2 expression is associated with clinical staging and poor prognosis of NPC.Taken together,the present findings suggest that circMAN1A2 promotes VM formation and progression of NPC through miR-940/ERBB2 axis and further activates the PI3K/AKT/mTOR pathway.Therefore,circMAN1A2 may become a biomarker and therapeutic target for anti-angiogenic therapy in patients with nasopharyngeal carcinoma.

Molecular Mimicry, the Hygiene Hypothesis, Stealth Infections and Other Examples of Disconnect between Medical Research and the Practice of Clinical Medicine in Autoimmune Disease

Autoimmune disorders have been on a steep rise in the industrialized countries over the past several decades and while research has been starting to develop a detailed understanding of pathophysiology and many of the underlying mechanisms, any meaningful incorporation of this information into clinical medicine has been painfully slow. Concepts of molecular mimicry, the hygiene hypothesis, intestinal hyper-permeability (leaky gut syndrome) and aggressive use of predictive antibody testing are explored in this article with examples given on how emerging information on these phenomena may aid the clinician in a new, more proactive, approach to management of these conditions.

Molecular mimicry in cutaneous autoimmune diseases

The emulation of characteristics of a different organism to gain biological advantage is a common phenomenon in nature,described and defined with the term"mimicry"in the second half of the 19th century.In the last decades,mimicry at molecular level has been evidenced as a method used by several pathogen microrganisms to control metabolic functions of infected cells and elude host’s immune system.Because of molecular mimicry,immune reactions against microbial molecules can turn against the mimicked self-molecules in predisposed subjects,leading to autoimmunity.This pathogenic mechanism,which gives a possible explanation for the specific epidemiological and chronological association between some infections and some autoimmune diseases,is well known and verified in many fields of medicine,but not adequately studied in dermatology:experimental data are available only for leprosy,atopic dermatitis,Beh?et’s disease,Vogt-Koyanagi-Harada syndrome and systemic erythematous lupus,while for few other diseases its role is hypothetical or suggested on the basis of single,small experiments or anecdotal reports.An overview of available data and hypotheses about the role of molecular mimicry in autoimmune cutaneous diseases is presented here,together with the perspectives offered by the use of bioinformatics and the personal experi-ence of the author in this field.

Effects of Vasculogenic Mimicry on Postoperative Recurrence and Progression of Non-Small Cell Lung Cancer

Vasculogenic mimicry(VM)in lung cancer shortens overall survival(OS)but its'associations with postoperative recurrence and progression of early non-small cell lung cancer(NSCLC)remain unclear.The purpose of this study was to analyze the association of VM with postoperative recurrence and progression of NSCLC as well as the effect of VM on postoperative recurrence-free survival(RFS).This study included NSCLC patients and detected VM in surgical specimens.The associations ofVM with the recurrence and progression were analyzed to assess the effect ofVM on postoperative RFS in NSCLC.A total of 80 NSCLC cases were followed up for 3 years.During follow-up,35 cases showed recurrence and progression where 5(6.25%)cases had simple local recurrence and the other 30(37.5%)cases had distant metastasis.The recurrence and progression rates in the first,second,and third years were 12.50%,23.75%,and 7.50%,respectively.The median RFS was 14.2 months.VM was detected in 30 out of 80 cases and was significantly correlated with tumor differentiation(r=0.365)and clinical stage(r=0.374)(both,P=0.001).Local recurrence of NSCLC was not correlated with VM,unlike distant metastasis(r=0.598,P<0.001).Average RFS was significantly longer in NSCLC patients without VM compared with the VM group 3 years post-operation(32 months versus 18 months,log-rank test P<0.001).Considering these,VM is significantly correlated with postoperative distant metastasis of NSCLC in which it is of a certain value for predicting poor prognosis in NSCLC.

A new blood supply for human primary gallbladder carcinomas:vasculogenic mimicry,and its correlation with VEGF and significance

Objective To explore if vasculogenic mimicry (VM) exists in human primary gallbladder carcinomas and evaluate the correlation between the VM and expression of vascular epithelial growth factor (VEGF) in gallbladder carcinomas and its significance. MethodsSeventy-four carcinomas, 10 adenomas and 10 chronic inflammatory lesions of the gallbladder underwent operation and confirmed histopathologically were studied. Clinical-pathological data and survival of each patient with gallbladder carcinoma were recorded and followed-up. VM in human gallbladder carcinomas was observed under light microscope by HE staining, CD31 and PAS staining; the expression of VEGF proteins in each paraffin section of each patient in vivo was determined by Envision method of immunohistochemistry; the correlation among the VM, VEGF expression and their clinical significance in the patients with gallbladder carcinomas were analyzed and compared by Kaplan-Meier actuarial survival curves and Cox multiple factors. Results①13.5% (10/74) of human gallbladder carcinomas were found to contain VM, namely intratumoral, tumor cell-lined extracellular matrix (ECM)-rich, PAS-positive and vasculogenic-like network patterns. VM was associated with histological type (χ2=10.241,P=0.017), hepatic metastasis (χ2=4.238,P=0.042) and poor overall survival (χ2=5.722 1,P=0.016). ②Expression of VEGF was increased significantly in carcinomas with or without VM than adenomas and inflammatory lesions of the gallbladder (P<0.000 1) in vivo; VEGF expression in the gallbladder carcinomas without VM was increased significantly than that with VM (P=0.018 2). ③There is positive correlation between expression of VEGF and the gallbladder carcinomas without VM in the cases of Nevin stage (P=0.003 5), invasion depth (P=0.005 9), liver metastases (P=0.037 3) and lymph node metastases (P=0.000 1), the same correlation was only observed between expression of VEGF and the gallbladder carcinomas with VM in the cases of liver metastases (P=0.032 3). When being compared the non-VM gallbladder carcinomas with the VM gallbladder carcinomas, expression of VEGF in the same conditions of Nevin stage (S3～S5, P=0.049 0) was higher significantly in the gallbladder carcinomas without VM than those with VM. ④The non-VM group underwent operation with positive expression of VEGF had longer 5-year survival than the VM group (P=0.007 2), furthermore, the non-VM group underwent operation with negative expression of VEGF had longer 5-year survival than the positive expression group (P=0.031). Also, VM, as invasive depth, lymph node metastasis, hepatic metastasis and operational method, is an independent, risk prognostic factor for patients with gallbladder carcinoma by Cox multiple factor analysis. ConclusionsVM, as a new blood supply for the growth of gallbladder carcinomas, is found to exist in the patients with gallbladder carcinomas. Increased expression of VEGF and its negative correlation with VM were observed in the gallbladder carcinomas. It is showed that VM is an independent risk prognostic factor in patients with gallbladder carcinoma, and VEGF is an important clinical marker for evaluation of Nevin stage, invasion depth, lymph node or liver metastases and prognosis in patients with gallbladder carcinoma; VM and VEGF are especially of important markers for estimating of prognosis in the gallbladder carcinoma patients.

ATM Activation is Key in Vasculogenic Mimicry Formation by Glioma Stem-like Cells

Objective Vasculogenic mimicry(VM)is a novel vasculogenic process integral to glioma stem cells(GSCs)in glioblastoma(GBM).However,the relationship between VM and ataxia-telangiectasia mutated(ATM)serine/threonine kinase activation,which confers chemoradiotherapy resistance,remains unclear.Methods We investigated VM formation and phosphorylated ATM(pATM)levels by CD31/GFAPperiodic acid-Schiff dual staining and immunohistochemical staining in 145 GBM specimens.Glioma stem-like cells(GSLCs)derived from the formatted spheres of U87 and U251 cell lines and their pATM level and VM formation ability were examined using western blot and three-dimensional culture.For the examination of the function of pATM in VM formation by GSLCs,ATM knockdown by shRNAs and deactivated via ATM phosphorylation inhibitor KU55933 were studied.Results VM and high pATM expression occurred in 38.5% and 41.8% of tumors,respectively,and were significantly associated with reduced progression-free and overall survival.Patients with VM-positive GBMs exhibited higher pATM levels(r_(s)=0.425,P=0.01).The multivariate analysis established VM as an independent negative prognostic factor(P=0.002).Furthermore,GSLCs expressed high levels of pATM and formed vascular-like networks in vitro.ATM inactivation or knockdown hindered VM-like network formation concomitant with the downregulation of pVEGFR-2,VE-cadherin,and laminin B2.Conclusion VM may predict a poor GBM prognosis and is associated with pATM expression.We propose that pATM promotes VM through extracellular matrix modulation and VE-Cadherin/pVEGFR-2 activation,thereby highlighting ATM activation as a potential target for enhancing anti-angiogenesis therapies for GBM.

Biological scaffold as potential platforms for stem cells:Current development and applications in wound healing

Wound repair is a complex challenge for both clinical practitioners and researchers.Conventional approaches for wound repair have several limitations.Stem cell-based therapy has emerged as a novel strategy to address this issue,exhibiting significant potential for enhancing wound healing rates,improving wound quality,and promoting skin regeneration.However,the use of stem cells in skin regeneration presents several challenges.Recently,stem cells and biomaterials have been identified as crucial components of the wound-healing process.Combination therapy involving the development of biocompatible scaffolds,accompanying cells,multiple biological factors,and structures resembling the natural extracellular matrix(ECM)has gained considerable attention.Biological scaffolds encompass a range of biomaterials that serve as platforms for seeding stem cells,providing them with an environment conducive to growth,similar to that of the ECM.These scaffolds facilitate the delivery and application of stem cells for tissue regeneration and wound healing.This article provides a comprehensive review of the current developments and applications of biological scaffolds for stem cells in wound healing,emphasizing their capacity to facilitate stem cell adhesion,proliferation,differentiation,and paracrine functions.Additionally,we identify the pivotal characteristics of the scaffolds that contribute to enhanced cellular activity.