lncRNA-ATB介导的上皮间质转化在胃癌进展中的机制研究

目的 探讨lncRNA-ATB介导的上皮间质转化在胃癌进展中的可能机制。方法 采用生物信息学分析预测lncRNA-ATB的下游结合分子并采用荧光素酶报告基因验证。收集联勤保障部队第九八〇医院2017年1月—2019年12月胃癌及癌旁组织标本56例,采用qRT-PCR分析lncRNA-ATB及下游结合分子在胃癌及癌旁组织中的表达水平及二者之间的相关性,并分析二者与胃癌临床病理特征的相关性;在敲降lncRNA-ATB前后的胃癌BGC-823细胞系中,采用qRT-PCR及Western blot实验验证miR-200a、β-catenin、vimentin、E-cadherin表达水平的变化。结果 生物信息学分析发现lncRNA-ATB与miR-200a有直接结合位点,miR-200a与β-catenin能直接结合并采用荧光素酶报告基因验证。lncRNA-ATB在胃癌组织中较癌旁组织中明显高表达(P＜0.001),miR-200a在胃癌组织中较癌旁组织中明显低表达,差异有统计学意义(P＜0.001)。在胃癌组织中lncRNA-ATB与miR-200a表达水平呈负相关(r=-0.317,P=0.017)。lncRNA-ATB在Ⅲ、Ⅳ期胃癌较Ⅰ、Ⅱ期表达水平明显升高,淋巴结转移阳性组、脉管内癌栓阳性及肿瘤低分化组lncRNA-ATB表达水平更高,差异有统计学意义(P＜0.001)。miR-200a在Ⅲ、Ⅳ期胃癌患者较Ⅰ、Ⅱ期患者表达水平明显降低,淋巴结转移阳性组、脉管内癌栓阳性及肿瘤低分化组miR-200a表达水平明显降低,差异有统计学意义(P＜0.05)。在胃癌BGC-823细胞系中敲降lncRNA-ATB后β-catenin和vimentin表达降低、E-cadherin表达升高,差异有统计学意义(P＜0.05)。结论 lncRNA-ATB通过与miR-200a结合,影响β-catenin的表达促进上皮间质转化进程从而影响胃癌进展。

Mechanism of lncRNA-ATB mediated epithelial mesenchymal transition in the progression of gastric cancer

Objective The objective of this study was to investigate the possible mechanism of lncRNA-ATB mediated epithelial-mesenchymal transition(EMT)in the progression of gastric cancer. Methods The downstream binding molecules of lncRNA-ATB were predicted by bioinformatics analysis and verified by luciferase reporter gene.A total of 56 gastric cancer and adjacent tissue specimens from the 980th Hospital of the Joint Logistics Support Force were collected from January 2017 to December 2019.The levels of lncRNA-ATB and the downstream binding molecules in gastric cancer and adjacent tissues as well as their relationship were analyzed by qRT-PCR.Its correlation with clinicopathological features of gastric cancer was also analyzed.The expression of miR-200a,β-catenin,vimentin and E-cadherin was confirmed by qRT-PCR and Western blot in gastric cancer BGC-823 cells before and after knockdown of lncRNA-ATB. Results Bioinformatics analysis showed that lncRNA-ATB had a direct binding site to miR-200a,and miR-200a could directly bind to β-catenin,which was verified by luciferase reporter gene.The expression of lncRNA-ATB in gastric cancer tissues was significantly higher than that in adjacent tissues(P＜0.001),and the expression of miR-200a in gastric cancer was significantly lower than that in adjacent tissues,the difference was statistically significant(P＜0.001).There was a negative correlation between the levels of lncRNA-ATB and miR-200a in gastric cancer tissues(r=-0.317,P=0.017).The expression of lncRNA-ATB in the stage III and IV gastric cancer was significantly higher than that in the stage I and II gastric cancer,and the expression of lncRNA-ATB in patients with the lymph node metastasis positive group,vascular tumor thrombus positive group and tumor poorly differentiated group was significantly higher than that in the negative group,and the difference was statistically significant(P＜0.001).The expression of miR-200a in the stage III and IV gastric cancer patients was significantly lower than that in the stage I and II patients,and the expression of miR-200a in patients with the lymph node metastasis positive group,vascular tumor thrombus positive group and tumor poorly differentiated group was significantly lower than that in the negative group,and the difference was statistically significant(P＜0.05).After knockdown of lncRNA-ATB in BGC-823 cells,the expression of β-catenin and vimentin was decreased and the expression of E-cadherin was increased,and the differences were statistically significant(P＜0.05). Conclusion lncRNA-ATB can affect the progression of gastric cancer by binding to miR-200a,affecting the expression of β-catenin and promoting the process of EMT.