Prognositic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma

Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in tumor metastasis,regulating the migration and adhesion of tumor cells at the primary site.However,as a type of programmed cell death,anoikis is rarely studied in osteosarcoma,especially in the tumor immune microenvironment.This study aims to clarify prognostic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma.Methods:Anoikis-related genes(ANRGs)were obtained from GeneCards.Clinical information and ANRGs expression profiles of osteosarcoma patients were sourced from the therapeutically applicable research to generate effective therapies and Gene Expression Omnibus(GEO)databases.ANRGs highly associated with tumor immune microenvironment were identified by the estimate package and the weighted gene coexpression network analysis(WGCNA)algorithm.Machine learning algorithms were performed to construct long-term survival predictive strategy,each sample was divided into high-risk and low-risk subgroups,which was further verified in the GEO cohort.Finally,based on single-cell RNA-seq from the GEO database,analysis was done on the function of signature genes in the osteosarcoma tumor microenvironment.Results:A total of 51 hub ANRGs closely associated with the tumor microenvironment were identified,from which 3 genes(MERTK,BNIP3,S100A8)were selected to construct the prognostic model.Significant differences in immune cell activation and immune-related signaling pathways were observed between the high-risk and low-risk groups based on tumor microenvironment analysis(all P<0.05).Additionally,characteristic genes within the osteosarcoma microenvironment were identified in regulation of intercellular crosstalk through the GAS6-MERTK signaling pathway.Conclusion:The prognostic model based on ANRGs and tumor microenvironment demonstrate good predictive power and provide more personalized treatment options for patients with osteosarcoma.

Apigenin is an anoikis sensitizer with strong anti-metastatic properties in experimental breast cancer

Loss of susceptibility to anoikis signals is a crucial step in metastasis.Anoikis resistance therefore represents a promising adjuvant therapeutic target for cancer management.In this study,we have conducted a rationalized screening to search for novel leading anoikis sensitizer from daily foods.Among 19 tested dietary phytochemicals,the best results were obtained with apigenin,a natural component of celery.Phenotypically,apigenin sensitized breast cancer cells to anoikis,lowered the number of circulating tumor cells,and protected against breast cancer metastasis to lung in mice.Mechanistically,we demonstrated that the thromboxane A_(2)(TXA_(2))-TXA_(2)receptor(TP)axis has a critical role in acquired anoikis resistance by activating PI3K-Akt signaling pathway.Blockage of TXA_(2)signaling up-regulated p53 as well as its target gene p21,caused a G1 phase arrest,and finally led to apoptosis in breast cancer cells.TXA_(2)level was positively correlated with breast cancer cell anoikis rate,and apigenin significantly inhibited TXA_(2)biosynthesis in vitro and in vivo.Collectively,we identified apigenin as a potent anoikis sensitizer with anti-metastatic properties in a mouse model of breast cancer,and these findings might provide a rationale for introducing apigenin supplementation to breast cancer patients.

人α干扰素诱导骨肉瘤细胞Anoikis凋亡

目的 :恶性肿瘤细胞逃避Anoikis凋亡的特性是其原位侵袭和远处转移的一个重要原因。本文旨在研究应用人干扰素 (IFN)α2a诱导骨肉瘤细胞出现Anoikis凋亡 ,并深入探讨其产生机理及信号传导途径。方法 :采用抑制接触培养法建立细胞Anoikis凋亡诱导模型。观测IFN α2a诱导骨肉瘤细胞MG 6 3产生的Anoikis凋亡。TUNEL法形态学检测MG 6 3细胞凋亡 ,流式细胞仪定量检测细胞凋亡程度和细胞表面整联蛋白受体表达。特异性底物切开法检测半胱氨酸天门冬氨酸特异性蛋白酶 (cysteineaspartate specificproteases ,caspase)信号途径。 结果 :人IFN α2a可明显诱导骨肉瘤细胞MG 6 3产生Anoikis现象 ,并诱导了MG 6 3细胞caspase 8和caspase 3的活性 ,但IFN对整联蛋白亚单位α4 ,α5及αv无明显影响 ,上述整联蛋白封闭抗体对IFNα 2a诱导的MG 6 3细胞Anoikis凋亡无明显影响。结论 :人干扰素α2a可以在体外通过调节细胞cas pase信号途径 ,诱导骨肉瘤细胞MG 6 3产生Anoikis现象 。

Inhibition of signal transducer and activator of transcription 3 expression by RNA interference suppresses invasion through inducing anoikis in human colon cancer cells

AIM:To investigate the roles and mechanism of signal transducer and activator of transcription 3 (STAT3) in invasion of human colon cancer cells by RNA interference. METHODS: Small interfering RNA (siRNA) targeting Signal transducer and activator of transcription 3 (STAT3) was transfected into HT29 colon cancer cells. STAT3 protein level and DNA-binding activity of STAT3 was evaluated by western blotting and electrophoretic mobility shift assay (EMSA), respectively. We studied the anchorage-independent growth using colony formation in soft agar, and invasion using the boyden chamber model, anoikis using DNA fragmentation assay and terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL), respectively. Western blot assay was used to observe the protein expression of Bcl-xL and survivin in colon cancer HT29 cells. RESULTS: RNA interference (RNAi) mediated by siRNA leads to suppression of STAT3 expression in colon cancer cell lines. Suppression of STAT3 expression by siRNA could inhibit anchorage-independent growth, and invasion ability, and induces anoikis in the colon cancer cell line HT29. It has been shown that knockdown of STAT3 expression by siRNA results in a reduction in expression of Bcl-xL and survivin in HT29 cells. CONCLUSION: These results suggest that STAT3 siRNA can inhibit the invasion ability of colon cancer cells through inducing anoikis, which antiapoptotic genes survivin and Bcl-xL contribute to regulation of anoikis.These studies indicate STAT3 siRNA could be a useful therapeutic tool for the treatment of colon cancer.

MiR-21 Suppresses Anoikis through Targeting PDCD4 and PTEN in Human Esophageal Adenocarcinoma

Anoikis is a form of apoptosis induced upon cell detachment from extracellular matrix. It has been determined that acquisition of resistance to anoikis is a critical step for tumor cell metastasis. MiR-21, the most prominent oncomiR, plays an important role in tumor progression. In this study, we revealed that up-regulation of miR-21 in human esophageal adenocarcinoma （EA） is associated with lymph node metastasis and poor survival rate. Because of the established anti-apoptosis effect of miR-21, it is tempting to speculate that miR-21 might contribute to tumor metastasis by regulating anoikis, qRT-PCR analysis demonstrated that miR-21 expression in OE33/AR cells （subpopulation of human EA OE33 cells that acquired resistance to anoikis） was significantly increased. Also, transfection of miR-21 mimics provided OE33 cells resisting to anoikis. By luciferase assays, we verified that PDCD4 and PTEN were the functional targets of miR-21. In mouse model, via tail vein injection experiment, we showed that the metastasis formation of OE33 cells in vivo could be mediated by changing the miR-21 expression pattern. Taken together, our findings suggested that miR-21 was involved in the regulation of anoikis in human EA cells. Targeting miR-21 may provide a novel strategy to prevent metastasis.

MicroRNA-6744-5p promotes anoikis in breast cancer and directly targets NAT1 enzyme

Objective:Anoikis is apoptosis that is induced when cells detach from the extracellular matrix and neighboring cells.As anoikis serves as a regulatory barrier,cancer cells often acquire resistance towards anoikis during tumorigenesis to become metastatic.MicroRNAs(miRNAs)are short strand RNA molecules that regulate genes post-transcriptionally by binding to mRNAs and reducing the expression of its target genes.This study aimed to elucidate the role of a novel miRNA,miR-6744-5 p,in regulating anoikis in breast cancer and identify its target gene.Methods:An anoikis resistant variant of the luminal A type breast cancer MCF-7 cell line(MCF-7-AR)was generated by selecting and amplifying surviving cells after repeated exposure to growth in suspension.Mi RNA microarray analysis identified a list of dysregulated miRNAs from which miR-6744-5 p was chosen for overexpression and knockdown studies in MCF-7.Additionally,the miRNA was also overexpressed in a triple-negative breast cancer cell line,MDA-MB-231,to evaluate its ability to impair the metastatic potential of breast cancer cells.Results:This study showed that overexpression and knockdown of miR-6744-5 p in MCF-7 increased and decreased anoikis sensitivity,respectively.Similarly,overexpression of miR-6744-5 p in MDA-MB-231 increased anoikis and also decreased tumor cell invasion in vitro and in vivo.Furthermore,NAT1 enzyme was identified and validated as the direct target of miR-6744-5 p.Conclusions:This study has proven the ability of miR-6744-5 p to increase anoikis sensitivity in both luminal A and triple negative breast cancer cell lines,highlighting its therapeutic potential in treating breast cancer.

Role of CD24 in Anoikis Resistance of Ovarian Cancer Cells

This study examined the effect of CD24 on anoikis of ovarian cancer cells. The expres- sion of CD24 was detected by RT-PCR and Western blotting in ovarian cancer cells with high metas- tatic potential （HO-8910PM cells） and low metastatic potential （A2780 cells）. Cell viability and cell proliferation were detected by MTT assay in suspension culture and adhesion culture. Soft agar cul- ture was used to observe the colony formation. Anoikis was flow cytometrically detected. The results showed that the expression levels of CD24 mRNA and protein were significantly higher in HO-8910PM cells than in A2780 cells （P〈0.01）. In the suspension culture and soft agar culture, the HO-8910PM cells formed larger and more colonies （35.334-5.51 vs. 16.674-4.04; P〈0.01）, and showed a stronger resistance to anoikis than A2780 cells did （cell apoptosis rate： 5.93%4-2.38% vs. 16.32%-4-2.00%; P〈0.01）. After treated with CD24 monoclonal antibodies, the number of colony formed in HO-8910PM and A2780 cells was significantly decreased （9.334-2.52 and 8.004-2.00, re- spectively）, and the anoikis rate of the two cell lines was also markedly increased （23.11%4-2.87% and 28.36%~2.29%, respectively）. Our study suggested that CD24 may play an important role in the development of anoikis resistance and CD24 can be used as a new therapeutic target to induce anoikis and inhibit metastasis in ovarian cancer.

EZH2 Contributes to Anoikis Resistance and Promotes Epithelial Ovarian Cancer Peritoneal Metastasis by Regulating m6A

Objective:Histone modification has a significant effect on gene expression.Enhancer of zeste homolog 2(EZH2)contributes to the epigenetic silencing of target chromatin through its roles as a histone-lysine N-methyltransferase enzyme.The development of anoikis resistance in tumor cells is considered to be a critical step in the metastatic process of primary malignant tumors.The purpose of this study was to investigate the effect and mechanism of anoikis resistance in ovarian adenocarcinoma peritoneal metastasis.Methods:In addition to examining EZH2 protein expression in ovarian cancer omental metastatic tissues,we established a model of ovarian cancer cell anoikis and a xenograft tumor model in nude mice.Anoikis resistance and ovarian cancer progression were tested after EZH2 and N6-methyladenosine(m6A)levels were modified.Results:EZH2 expression was significantly higher in ovarian cancer omental metastatic tissues than in normal ovarian tissues.Reducing the level of EZH2 decreased the level of m6A and ovarian cancer cell anoikis resistance in vitro and inhibited ovarian cancer progression in vivo.M6a regulation altered the effect of EZH2 on anoikis resistance.Conclusion:Our results indicate that EZH2 contributes to anoikis resistance and promotes ovarian adenocarcinoma abdominal metastasis by m6A modification.Our findings imply the potential of the clinical application of m6A and EZH2 for patients with ovarian cancer.

Induction of Apoptosis and Anoikis by Bit1 in Pancreatic Cancer Cells

Pancreatic cancer is a highly aggressive disease with a very high mortality rate among all human cancers. The poor prognosis is in part due to intrinsic resistance to the apoptosis-inducing effects of radio- and chemotherapy. To find alternative cell death pathways that can bypass the apoptotic resistance of pancreatic cancer cells, we examined the role of the novel anoikis effector Bit1 (Bcl-2 inhibitor of transcription) in the survival and apoptotic resistance of pancreatic cancer cells. Bit1 is a mitochondrial protein that induces a caspase-independent apoptosis upon its release into the cytosol following loss of integrin-mediated attachment to extracellular matrix (anoikis). In this report, we observed that ectopic expression of Bit1 in the cytosol reduced viability and induced caspase-independent apoptosis in human pancreatic cancer cell lines, Miapaca-2 and PANC-1. While increased expression of mitochondrial Bit1 in these cells did not induce apoptosis under attached conditions, detachment significantly induced higher level of apoptosis in mitochondrial Bit1-transfected cells than in control transfected cells. Conversely, downregulation of endogenous Bit1 in PANC-1 cells further enhanced their anoikis resistance. Furthermore, exogenous expression of mitochondrial Bit1 in Miapaca-2 cells inhibited their anchorage-independent growth and enhanced their sensitivity to etoposide-mediated apoptosis. Mechanistically, we found that the Bit1 apoptosis function is in part dependent on the groucho related Amino-terminal Enhancer of Split (AES) expression and is abrogated by the transcriptional corepressor TLE1 protein. Consistent with our in vitro findings that Bit1 is an effector of apoptosis in pancreatic tumor cells, we find that Bit1 is significantly downregulated in a fraction of advanced stages of human pancreatic carcinoma tissues. Taken together, these findings indicate that the Bit1-apoptotic pathway can be targeted to trigger cell death in pancreatic cancer cells and implicate Bit1 as a novel therapeutic agent in attenuating pancreatic chemoresistance.

PTEN induces anoikis through its phosphatase activity in human bladder transitional carcinoma cells BIU-87

Objective:To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87.Methods:BIU-87 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN(C124A-PTEN)in vitro.The PTEN expression and the phosphorylation levels of focal adhesion kinase(FAK)and protein kinase B(PKB/Akt)were detected by Western blotting.Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells.Results: Compared with the control group,PTEN expression in the cells transfected with wild-type PTEN increased to 210%–260%, while the phosphorylation level of FAK and Akt decreased 59%(P<0.01)and 89%(P<0.01),respectively.And the anoikis percentage increased from 8.32±0.57%to 37.62±2.12%.In the cells transfected with C124A-PTEN,neither the phos- phorylation of FAK and Akt nor the anoikis percentage had obviously changed,although the PTEN expression enhanced remarkably in comparison with the control.Conclusion:Through its phosphatase activity,tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt,and induce anoikis in human bladder transitional carcinoma cells BIU-87.

Comprehensive bioinformatics analysis and experimental validation:An anoikis-related gene prognostic model for targeted drug development in head and neck squamous cell carcinoma

We analyzed RNA-sequencing(RNA-seq)and clinical data from head and neck squamous cell carcinoma(HNSCC)patients in The Cancer Genome Atlas(TCGA)Genomic Data Commons(GDC)portal to investigate the prognostic value of anoikis-related genes(ARGs)in HNSCC and develop new targeted drugs.Differentially expressed ARGs were screened using bioinformatics methods;subsequently,a prognostic model including three ARGs(CDKN2A,BIRC5,and PLAU)was constructed.Our results showed that the model-based risk score was a good prognostic indicator,and the potential of the three ARGs in HNSCC prognosis was validated by the TISCH database,the model’s accuracy was validated in two independent cohorts of the Gene Expression Omnibus database.Immune correlation analysis and half-maximal inhibitory concentration were also performed to reveal the different landscapes of TIME between risk groups and to predict immuno-and chemo-therapeutic responses.Potential small-molecule drugs for HNSCC were subsequently predicted using the L1000FWD database.Finally,in vitro experiments were used to verify the database findings.The relative ARG mRNA expression levels in HNSCC and surrounding normal tissues remained consistent with the model results.BIRC5 knockdown inhibited anoikis resistance in WSU-HN6 and CAL-27 cells.Molecular docking,real-time PCR,cell counting kit-8(CCK-8),plate clone,and flow cytometry analyses showed that small-molecule drugs predicted by the database may target the ARGs in the prognostic model,inhibit HNSCC cells survival rate,and promote anoikis in vitro.Therefore,we constructed a new ARG model for HNSCC patients that can predict prognosis and immune activity and identify a potential small-molecule drug for HNSCC,paving the way for clinically targeting anoikis in HNSCC.

Mammalian Ste20-like kinase 1 inhibition as a cellular mediator of anoikis in mouse bone marrow mesenchymal stem cells

BACKGROUND The low survival rate of mesenchymal stem cells(MSCs)caused by anoikis,a form of apoptosis,limits the therapeutic efficacy of MSCs.As a proapoptotic molecule,mammalian Ste20-like kinase 1(Mst1)can increase the production of reactive oxygen species(ROS),thereby promoting anoikis.Recently,we found that Mst1 inhibition could protect mouse bone marrow MSCs(mBMSCs)from H 2 O 2-induced cell apoptosis by inducing autophagy and reducing ROS production.However,the influence of Mst1 inhibition on anoikis in mBMSCs remains unclear.AIM To investigate the mechanisms by which Mst1 inhibition acts on anoikis in isolated mBMSCs.METHODS Poly-2-hydroxyethyl methacrylate-induced anoikis was used following the silencing of Mst1 expression by short hairpin RNA(shRNA)adenovirus transfection.Integrin(ITGs)were tested by flow cytometry.Autophagy and ITGα5β1 were inhibited using 3-methyladenine and small interfering RNA,respe-ctively.The alterations in anoikis were measured by Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling and anoikis assays.The levels of the anoikis-related proteins ITGα5,ITGβ1,and phospho-focal adhesion kinase and the activation of caspase 3 and the autophagy-related proteins microtubules associated protein 1 light chain 3 II/I,Beclin1 and p62 were detected by Western blotting.RESULTS In isolated mBMSCs,Mst1 expression was upregulated,and Mst1 inhibition significantly reduced cell apoptosis,induced autophagy and decreased ROS levels.Mechanistically,we found that Mst1 inhibition could upregulate ITGα5 and ITGβ1 expression but not ITGα4,ITGαv,or ITGβ3 expression.Moreover,autophagy induced by upregulated ITGα5β1 expression following Mst1 inhibition played an essential role in the protective efficacy of Mst1 inhibition in averting anoikis.CONCLUSION Mst1 inhibition ameliorated autophagy formation,increased ITGα5β1 expression,and decreased the excessive production of ROS,thereby reducing cell apoptosis in isolated mBMSCs.Based on these results,Mst1 inhibition may provide a promising strategy to overcome anoikis of implanted MSCs.

Cellular Anchorage Sensing and Anoikis

Normal epithelial cells that lose the integrindependent anchorage to their extracellular matrix trigger anoikis,while metastatic tumor cells bypass anoikis pathway, which is one of the key events to achieve the metastasis. Physiological role of anoikis is also involved during embryonic development and tissue homeostasis, suggesting that anoikis must be strictly regulated at some level. Despite its importance, the molecular pathways involved in the regulation of anoikis and the proximal signals reporting loss of anchorage are poorly understood. Recent studies suggest an adaptor protein p66Shc, localizing at focal adhesions,mediates anoikis through activation of RhoA. However, expression of p66Shc is inadequate in metastatic cancer cells, failing to initiate anoikis and promoting tumor metastasis. Reexpression of proapoptotic protein p66Shc can restore the susceptibility to anoikis.Thus, p66Shc may be a potential target molecule for diagnosis of tumor metastasis and for tumor treatment.

Anoikis induction by glycoprotein from <i>Laminaria japonica</i>in HT-29 cells

We extracted a glycoprotein from the brown alga Laminaria japonica (LJGP). We previously demonstrated that LJGP induced apop- tosis in HT-29 colon cancer cells via the Fas- and the mitochondrial signaling pathway, and cell-cycle arrest. However, its effect on the cell membrane remained unknown. In this study, we identified the involvement of matrix metalloproteinase (MMP), integrin, and Epi- thelial (E)-cadherin in LJGP-induced apoptosis in HT-29 cells. LJGP treatment increased the expression and activity of MMP-2 and MMP-9. Furthermore, LJGP decreased the expression of integrin αν, β3, β5, β6 and E- cadherin. Consistent with a decreased expression of E-cadherin, LJGP inhibited the Wnt signaling pathway. Moreover, activation of downstream molecules of integrin, including focal adhesion kinase (FAK), the Src family of protooncogenic tyrosine kinases, extracellular signal-related kinase (ERK), and phosphatidyl inositol 3 kinase (PI-3K) were also decreased. These findings suggest that LJGP-induced apoptosis of HT-29 cells involves possible ECM disruption and cell detachment, which are executed principally through the activation of MMPs and by a decrease of adhesion molecules, contributing to a down-regulation of the PI-3K, MAPK, and Wnt signaling pathways. Apoptosis induced by ECM disruption or cell detachment is also known as anoikis. We can say that LJGP induces anoikis in HT-29 cells.

Pressure shift mediated anoikis of endothelial cells in the flow field in vitro

Dramatic changes of pressure in the local circulation flow field would lead to alterations in biorheological characteristics of Endothelial cells(ECs), and futher resulted in the apoptosis induced by loss of anchorage, a form of cell death known as anoikis. In this study, we set levels of pressure(negative and positive pressure) loaded ECs groups and non-activated cultured ECs ,single shear stress loaded ECs as control group to demonstrate the effects of pressure shift on cell morphogenesis and adhesion. Furthermore, we investigate the effects of pressure shift on ECs proli- feration and apoptosis to elucidate the influences of pressure shift on vitality of ECs. We present these data here to suggest that the negative pressure might be another important factor beyond velocity and shear stress in biomechanical impairment on ECs, then to trigger the apoptosis with the extracellular matrix (ECM) detachment (anoikis). As the negative pressure is thought to play a role in the anoikis process, these results have implications for both the path- ogenesis and therapeutics investigations of stenostic vessel diseases and the future vascular tissue engineering.

Advancements in precision nanomedicine design targeting the anoikis-platelet interface of circulating tumor cells

Tumor metastasis,the apex of cancer progression,poses a formidable challenge in therapeutic endeavors.Circulating tumor cells(CTCs),resilient entities originating from primary tumors or their metastases,significantly contribute to this process by demonstrating remarkable adaptability.They survive shear stress,resist anoikis,evade immune surveillance,and thwart chemotherapy.This comprehensive review aims to elucidate the intricate landscape of CTC formation,metastatic mechanisms,and the myriad factors influencing their behavior.Integral signaling pathways,such as integrin-related signaling,cellular autophagy,epithelial-mesenchymal transition,and interactions with platelets,are examined in detail.Furthermore,we explore the realm of precision nanomedicine design,with a specific emphasis on the anoikis‒platelet interface.This innovative approach strategically targets CTC survival mechanisms,offering promising avenues for combatting metastatic cancer with unprecedented precision and efficacy.The review underscores the indispensable role of the rational design of platelet-based nanomedicine in the pursuit of restraining CTC-driven metastasis.

酪氨酸激酶受体B与人卵巢癌OVCAR-3细胞侵袭能力的关系

背景与目的:失巢凋亡抑制因子酪氨酸激酶受体B(tyrosine kinase receptor B,TrkB)能诱导正常上皮细胞的恶性转化并且使该细胞具有高转移能力。TrkB在神经母细胞瘤和其他多种人类高侵袭性恶性肿瘤组织中过度表达,TrkB在卵巢癌细胞中的表达及其与卵巢癌细胞的高侵袭能力的关系的研究鲜有报道。本研究探讨失巢凋亡抑制因子酪氨酸激酶受体B(tyrosine kinase receptor B,TrkB)与人卵巢癌OVCAR-3细胞侵袭能力的关系。方法:RT-PCR和Western印迹法检测卵巢癌细胞系OVCAR-3细胞贴壁培养、细胞立体培养以及细胞立体培养得到的多细胞团簇经胰酶消化成单细胞后再次贴壁培养细胞TrkB的表达差异;体内、体外细胞侵袭实验检测通过RNAi技术沉默TrkB后OVCAR-3细胞侵袭及转移能力的改变。结果:RT-PCR结果表明,OVCAR-3多细胞团簇中TrkBmRNA的表达高于贴壁细胞(P<0.001);Western印迹结果显示,与OVCAR-3贴壁细胞比较,立体培养细胞中全长TrkB表达升高[(17.47±0.58)%vs(8.93±0.19)%,(P<0.001)]。体内、体外细胞侵袭实验表明,OVCAR-3细胞团簇的侵袭转移能力较普通贴壁细胞明显增强(P<0.01);TrkB沉默后OVCAR-3的侵袭及转移能力受到抑制(P<0.01)。结论:TrkB通过失巢凋亡抑制机制介导了卵巢上皮性癌细胞的侵袭和转移。

Apoptosis commitment- translating survival signals into decisions on mitochondria

Most defective and unwanted cells die by apoptosis, cells without damaging the surrounding tissue. Once a an exquisitely controlled genetic programme for removing such cell has committed to apoptosis, the process is remarkably efficient, and is completed within a few minutes of initiation. This point of no retum for an apoptotic cell is commonly held to be the point at which the outer mitochondrial membrane is permeabilised, a process regulated by the Bcl-2 family of proteins. How these proteins regulate this decision point is central to diseases such as cancer where apoptotic control is lost. In this review, we will discuss apoptotic signalling and how a cell makes the irreversible decision to die. We will focus on one set of survival signals, those derived by cell adhesion to the extracellular matrix （ECM）, and use these to highlight the complexities of apoptotic signalling. In particular, we will illustrate how multiple signalling pathways converge to determine critical cell fate decisions.