水通道蛋白AQP2在原发性肝细胞肝癌多柔比星耐药机制中的作用研究

目的探索原发性肝细胞肝癌(HCC)多柔比星(doxorubicin,DOX)耐药的机制,为进一步提高HCC患者介入治疗的疗效提供前期探索。方法应用Western blotting方法检测DOX处理后的上皮间质化转变(EMT)的相关蛋白E-Cadherin和Vimentin表达情况,使用流式细胞仪观察细胞干性标记CD133的变化情况,使用基因芯片技术观察DOX处理后的细胞机制变化。结果 DOX能诱导HCC细胞发生上皮间质化转变,并且能提升HCC细胞CD133的比例(3.5%vs 35.5%,P<0.05);基因芯片提示HCC细胞内水通道蛋白AQP2基因显著上调;敲降AQP2基因后,能显著减弱DOX诱导HCC细胞产生EMT的效果。结论水通道蛋白AQP2在肝细胞肝癌多柔比星耐药机制中具有重要作用,降低AQP2的表达可以减弱多柔比星诱导肝癌细胞上皮间质化转变的效果。

Neural Wiskott-Aldrich syndrome protein(N-WASP)promotes distant metastasis in pancreatic ductal adenocarcinoma via activation of LOXL2

Pancreatic ductal adenocarcinoma(PDAC)is one of the most aggressive solid malignancies.A specific mechanism of its metastasis has not been established.In this study,we investigated whether Neural Wiskott-Aldrich syndrome protein(N-WASP)plays a role in distant metastasis of PDAC.We found that N-WASP is markedly expressed in clinical patients with PDAC.Clinical analysis showed a notably more distant metastatic pattern in the N-WASP-high group compared to the N-WASP-low group.N-WASP was noted to be a novel mediator of epithelialmesenchymal transition(EMT)via gene expression profile studies.Knockdown of N-WASP in pancreatic cancer cells significantly inhibited cell invasion,migration,and EMT.We also observed positive association of lysyl oxidase-like 2(LOXL2)and focal adhesion kinase(FAK)with the N-WASP-mediated response,wherein EMT and invadopodia function were modulated.Both N-WASP and LOXL2 depletion significantly reduced the incidence of liver and lung metastatic lesions in orthotopic mouse models of pancreatic cancer.These results elucidate a novel role for N-WASP signaling associated with LOXL2 in EMT and invadopodia function,with respect to regulation of intercellular communication in tumor cells for promoting pancreatic cancer metastasis.These findings may aid in the development of therapeutic strategies against pancreatic cancer.

TROVE2 regulated invasion and migration of hepatocellular carcinoma cells via heparanase

Background:The role of TROVE domain family member 2(TROVE2)has been well-demonstrated in autoimmune diseases;however,its involvement in liver cancer remains unclear.Therefore,this study aimed to explore the biological function and clinical significance of TROVE2 in hepatocellular carcinoma(HCC).Methods:The expression level of TROVE2 was analyzed in HCC and paired adjacent tissue samples using real-time reverse transcription-quantitative polymerase chain reaction.The impact of TROVE2 on migration and invasion in HCC cells was analyzed through Transwell assays and Western blotting.High-throughput transcriptome sequencing and bioinformatics analyses were performed to identify downstream target genes.Back-complementation experiments were employed to verify the influence of downstream proteins on TROVE2-induced invasion and migration of HCC cells.Results:TROVE2 exhibited significant overexpression in liver cancer tissue,correlating with shorter overall survival.Overexpression of TROVE2 facilitated the invasion,metastasis,and epithelial-mesenchymal transition(EMT)process of HCC cells,whereas TROVE2 knockdown restrained migration,invasion,and EMT in these cells.Transcriptome sequencing and bioinformatics analysis identified heparanase(HPSE)as a downstreamtarget protein of TROVE2.Subsequent back-complementation experiments provided evidence that HPSE overexpression promoted TROVE2-mediated prometastasis effects.Moreover,the study revealed that TROVE2 was capable of regulating the EMT pathway through GSK-3βphosphorylation.Conclusions:TROVE2 facilitated the invasion,migration,and EMT process ofHCC cells through phosphorylation of the HPSE/GSK-3βaxis,indicating its significance as an important protein in tumor progression.

Down-regulation of eIF5A-2 prevents epithelial-mesenchymal transition in non-small-cell lung cancer cells

Background:Epithelial-mesenchymal transition(EMT) is believed to be the critical process in malignant tumor invasion and metastases,and has a great influence on improving the survival rate in non-small-cell lung cancer(NSCLC) patients.Recent studies suggested that eukaryotic initiation factor 5A-2(eIF5A-2) might serve as an adverse prognostic marker of survival.We detected eIF5A-2 in NSCLC A549 cells,and found that the invasive capability correlates with the eIF5A-2 expression.Methods:Transforming growth factor(TGF)-β1 was used to induce EMT in A549 cells.Western blotting,immunofluorescence,wound healing assay,and transwell-matrigel invasion chambers were used to identify phenotype changes.Western blotting was also used to observe changes of the expression of eIF5A-2.We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence.We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers.Results:After stimulating with TGF-β1,almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities.These cells also had higher eIF5A-2 protein expression.Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly.Conclusions:The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells,which correlated with enhanced tumor invasion and metastatic capabilities.Furthermore,in the A549 cell line,the process of EMT phenotype change could be reversed by eIF5A-2 siRNA,with a consequent weakening of both invasive and metastatic capabilities.

Role of NOD2-regulated Snail expressionin epithelial-mesenchymal transition in podocyte ofdiabetic nephropathy

Objective To observe the expression of NOD2 and epithelial-mesenchymal transition(EMT)related proteins in podocytes in high glucose environment,and explore the molecular mechanism of NOD2 involved in EMT.Methods The human glomerular podocytes were the subjects of study.α-SMA and Nephrin expressions were detected by immunofluorescence;the mRNA and protein expressions of NOD2,Snail and EMT related proteins(α-SMA,Desmin,E-cadherin,Nephrin)were detected by real-time fluorescence quantitative PCR and Western blotting.The podocytes were stimulated by high-glucose after shRNA interfering the NOD2 expression,and the expressions of Snail and subsequent EMT-related proteins were detected by Western blotting.Prior to the activation of NOD2 by muramyl dipeptide(MDP),shRNA was used to interfere with the expression of Snail.Ecadherin,Nephrin,Desmin,and α-SMA were detected by Western blotting.Results After 24 hours of high glucose stimulation,PCR and Western blotting results showed that the expressions of NOD2 and Snail were significantly increased;the expressions of epithelial phenotype proteins E-cadherin and Nephrin were down-regulated;and the expressions of interstitial phenotype proteins Desmin and α-SMA were increased(all P<0.05);while there was no significant change in the hypertonic control group.After interference with NOD2,the abnormal expression of Snail and EMT related proteins were all recovered.After interference with Snail expression and compared with the MDP group,the protein expressions of E-cadherin and Nephrin were significantly increased(all P<0.05);the expressions of Desmin and α-SMA were significantly decreased.Conclusion High glucose can induce NOD2 expression in podocytes,and promote podocyte epithelial-mesenchymal transition by upregulating Snail expression.Gene intervention targeting the NOD2/Snail/EMT pathway can reduce high-glucose-induced podocyte injury and may provide new ideas for the treatment of diabetic nephropathy.

Cyclooxygenase-2 promotes ovarian cancer cell migration and cisplatin resistance via regulating epithelial mesenchymal transition

Objective: Drug-resistance and metastasis are major reasons for the high mortality of ovarian cancer(OC) patients. Cyclooxygenase-2(COX-2) plays a critical role in OC development. This study was designed to evaluate the effects of COX-2 on migration and cisplatin(cis-dichloro diammine platinum, CDDP) resistance of OC cells and explore its related mechanisms. Methods: Cell counting kit-8(CCK-8) assay was used to detect the cytotoxicity effects of celecoxib(CXB) and CDDP on SKOV3 and ES2 cells. The effect of COX-2 on migration was evaluated via the healing test. Western blot and real-time quantitative polymerase chain reaction(q PCR) were used to analyze E-cadherin, vimentin, Snail, and Slug levels. Results: COX-2 promoted drug-resistance and cell migration. CXB inhibited these effects. The combination of CDDP and CXB increased tumor cell sensitivity, reduced the amount of CDDP required, and shortened treatment administration time. COX-2 upregulation increased the expression of Snail and Slug, resulting in E-cadherin expression downregulation and vimentin upregulation. Conclusions: COX-2 promotes cancer cell migration and CDDP resistance and may serve as a potential target for curing OC.