miR-203a-3p通过靶向PRMT5抑制胃癌细胞增殖

目的:探讨miR-203a-3p在胃癌中的表达及其对胃癌细胞增殖的影响.方法:收集胃癌组织标本44例,采用Real-time PCR方法检测胃癌组织标本中miR-203a-3p的表达,并分析其表达水平与临床病理参数的关系;生物信息学预测miR-203a-3p的靶基因,并采用荧光素酶报告基因实验进行验证;免疫组化检测胃癌组织标本中PRMT5的表达情况,分析其表达水平与miR-203a-3p表达的相关性;利用脂质体介导的瞬时转染方法过表达miR-203a-3p或同时过表达miR-203a-3p和PRMT5,并通过CCK-8实验检测胃癌细胞的增殖情况.结果:胃癌组织中miR-203a-3p的表达水平与正常组织对照相比显著降低(P<0.01),并且miR-203a-3p的表达水平与肿瘤细胞的分化程度显著相关;荧光素酶报告基因实验证实miR-203a-3p可以直接结合在PRMT5 3'-UTR上,即PRMT5是miR-203a-3p的直接靶基因;在胃癌组织标本中,PRMT5表达水平显著高于正常组织对照(P<0.01),并且其表达水平与miR-203a-3p表达呈显著负相关(r=-0.4124,P<0.01);过表达miR-203a-3p后,胃癌BGC823细胞的增殖能力显著低于miR-NC对照组(P<0.01),并且,"挽救"实验表明在过表达miR-203a-3p的细胞中同时过表达PRMT5后会部分恢复miR-203a-3p对细胞增殖的抑制(P<0.01).结论:miR-203a-3p可通过下调靶基因PRMT5的表达,进而抑制胃癌细胞增殖.因此,miR-203a-3p可作为胃癌疾病临床治疗的潜在靶点.

miR-203a-3p inhibits the proliferation of gastric cancer cells by targeting PRMT5

Objective:To explore the expression of miR-203a-3p in gastric cancer and its effect on the proliferation of gastric cancer cells.Methods:A total of 44 gastric cancer tissues were collected.Real-time PCR was used to determine the expression of miR-203a-3p in gastric cancer tissues.The relationship between clinical characteristics and miR-203a-3p expression was also studied.Bioinformatics analysis was performed to search the potential targets of miR-203a-3p and subsequently verified by luciferase reporter assay.Immunohistochemical (IHC) staining was applied to detect the expression of PRMT5 in gastric cancer tissues.The relationship between miR-203a-3p and PRMT5 expression were also analyzed.CCK-8 assays were used to test the proliferation of BGC823 cells when miR-203a-3p or both miR-203a-3p and PRMT5 were transiently transfected.Results:miR-203a-3p was significantly downregulated in gastric cancer tissues compared with normal controls (P<0.01) and its expression showed a close correlation with the differentiation state of the cancer cells (P<0.05).The luciferase reporter assay confirmed that miR-203a-3p could directly bind to the 3'-UTR of PRMT5.So PRMT5 is a direct target of miR-203a-3p in gastric cancer.PRMT5 is obviously upregulated (P<0.01) and is inversely correlated with miR-203a-3p level (r=-0.4124,P<0.01) in gastric cancer tissues.In addition,the proliferative ability of BGC823 cells was significantly reduced (P<0.01) when miR-203a-3p was overexpressed.Remarkably,restoration of PRMT5 in miR-203a-3p-transfected gastric cancer BGC823 cells partially abrogated the inhibition of cell proliferation mediated through miR-203a-3p (P<0.01).Conclusion:miR-203a-3p inhibits cell proliferation by targeting PRMT5 in gastric cancer,so miR-203a-3p may be a candidate target for the treatment of gastric cancer.