CircKRT17与miR-485-5p互作调控Wnt/β-catenin通路影响胃癌发生发展的机制研究

Mechanism of the interaction between circular RNA KRT17 and miR-485-5p to regulate Wnt/β-catenin signaling pathway and affect the progression of gastric cancer

目的探讨circ KRT17在胃癌中的表达水平,并对circ KRT17在胃癌中的临床意义、生物学功能及内在机制进行评价。方法 2013年5月至2018年3月获得67例临床胃癌样本和对应的癌旁正常组织标本,并采用qRTPCR检测circ KRT17在胃癌组织和不同胃癌细胞株中的表达情况;分析circ KRT17的表达与胃癌患者临床病理学特征之间的关系;CKK-8法和平板克隆实验检测circ KRT17对胃癌细胞增殖能力的影响;Transwell实验检测circ KRT17对胃癌细胞迁移和侵袭能力的影响;裸鼠成瘤实验检测circ KRT17对胃癌细胞肿瘤异种移植的影响;荧光素酶报告基因检测circ KRT17与miR-485-5p以及miR-485-5p与Wnt3a之间的相互作用。结果 circ KRT17在胃癌组织中表达上调,与肿瘤分期、转移及患者预后不良密切相关。此外,降低circ KRT17表达显著抑制了胃癌细胞的增殖、迁移和侵袭,诱导了细胞凋亡。体内实验显示,敲低circ KRT17表达抑制肿瘤生长。机制上,研究发现circ KRT17作为miR-485-5p的海绵,增加Wnt3a的表达,从而激活Wnt/β-catenin信号。结论 circ KRT17/miR-485-5p/Wnt3a/β-catenin信号对胃癌的发生、发展至关重要。

Objective To investigate the expression of circ KRT17 in gastric cancer,and to evaluate its clinical significance,biological function and intrinsic mechanism.Methods A total of sixty-seven clinical gastric cancer samples and corresponding paracancer tissue samples were obtained from May 2013 to March 2018,and the expression of circ KRT17 in gastric cancer tissues and different gastric cancer cell lines were detected by qRT-PCR.The relationship between the expression of circ KRT17 and the clinicopathological features of gastric cancer was analyzed;CKK-8 and plate clone assay were used to determine the effect of circ KRT17 on gastric cancer cell proliferation;Transwell assay was performed to detect the effect of circ KRT17 on the migration and invasion ability of gastric cancer cells.Tumor formation assay in nude mouse models was used to detect effect of circ KRT17 on xenograft of gastric cancer cells.The luciferase reporter assay was used to detect the interaction between circ KRT17 and miR-485-5 p,and between miR-485-5 p and Wnt3 a.Results CircKRT17 overexpression was observed in gastric cancer tissues and closely associated with tumor stage,metastasis and unfavorable prognosis.Furthermore,reducing the expression of circ KRT17 significantly inhibited the proliferaion,migration and invasion of gastric cancer cells,and induced apoptosis.In vivo experiments showed that knockdown of circ KRT17 inhibited tumor growth.Mechanistically,we found that circ KRT17 acts as a sponge for miR-485-5 p to increase expression of Wnt3 a,thereby activating Wnt/β-catenin signaling.Conclusion CircKRT17/miR-485-5 p/Wnt3 a/β-catenin signaling was essential for the development and progression of gastric cancer.