奥沙利铂介导的长链非编码RNA XLOC-0000008调控微小RNA-142-3p/高迁移率族蛋白B1信号通路促进结直肠癌细胞自噬和耐药性的机制

目的探讨结直肠癌(CRC)中长链非编码RNA(lncRNA)XLOC-0000008调控微小RNA(microRNA,miR)-142-3p/高迁移率族蛋白B1(HMGB1)信号通路参与奥沙利铂促进细胞自噬的过程及其可能分子机制。方法采用奥沙利铂处理CRC细胞株HT29及HCT116(购自美国典型菌种保藏中心)进行芯片实验,奥沙利铂处理组为实验组,无奥沙利铂组为对照组,生信分析差异表达的lncRNAs及miRNAs;采用膜联蛋白V(Annexin V)/碘化丙锭双染流式细胞术检测CRC细胞凋亡;采用方法检测CRC细胞株中HMGB1蛋白及自噬相关蛋白的表达。采用实时荧光定量聚合酶链反应(RT-qPCR)方法检测细胞系中HMGB1 mRNA的表达水平;采用噻唑蓝(MTT)法检测细胞的生存率,两组计量资料的比较采用t检验或方差分析。结果奥沙利铂实验组HT29及HCT116细胞中XLOC-0000008的表达水平升高,且miR-142-3p的表达水平下降;随着奥沙利铂浓度增加细胞自噬活性增强,实验组自噬调控因子HMGB1在胞浆和胞外上清中表达均高于对照组(P<0.01);实验组HMGB1 mRNA表达高于对照组(P<0.01);与单独敲降HMGB1或单独奥沙利铂处理相比,奥沙利铂处理稳定敲降HMGB1的CRC细胞中p62蛋白水平低于对照组,且对奥沙利铂的敏感性显著增加(P<0.01),差异有统计学意义。结论CRC对于化疗药奥沙利铂抵抗可能由HMGB1诱导细胞自噬而引起,这一过程可能通过调控XLOC-0000008/miR-142-3p/HMGB1轴而实现。

Oxaliplatin mediated long non-coding RNA XLOC-0000008 regulates microRNA-142-3p/high mobility group protein B1 signaling pathway to promote autophagy and drug resistance in colorectal cancer cells

Objective To investigate the regulation of long non-coding RNA(lncRNA)XLOC-0000008 on microRNA(miRNA,miR)-142-3p/signaling pathway in colorectal cancer(CRC)and its possible molecular mechanism of oxaliplatin promoting autophagy.Methods The study was conducted from 2017 to 2019.CRC cells were treated with oxaliplatin for microarray experiments,and the differentially expressed lncRNAs and miRNAs were analyzed by bioinformatics analysis.Annexin V-fluoresceine isothiocyanate(FITC)/propidium iodide(PI)double-staining flow cytometry was used to detect the apoptosis of CRC cells.Western blotting was performed to measure the expression of HMGB1 and autophagy related proteins in CRC cells.Real-time fluorescent quantitative PCR(RT-qPCR)was employed to assess the expression level of HMGB1 mRNA in cell lines.Cell survival rate was determined by methyl thiazol tetrazolium(MTT)assay.Results Oxaliplatin significantly up-regulated the expression level of XLOC-0000008 in HT29 and HCT116 cells,and significantly down-regulated the expression level of miR-142-3p.With the increase of oxaliplatin concentration,autophagy activity was enhanced,and the expression of autophagy regulator HMGB1 in cytoplasm and extracellular supernatant was significantly increased.HMGB1 mRNA expression level was also significantly increased.As compared with HMGB1 knockout group or oxaliplatin treatment group,the expression level of p62 in CRC cells treated with oxaliplatin and stable knockout of HMGB1 was significantly decreased,and the sensitivity to oxaliplatin was significantly increased.Conclusion The resistance of CRC to oxaliplatin may be caused by autophagy induced by HMGB1,which may be achieved via regulating the XLOC-0000008/miR-142-3p/HMGB1 axis.