microRNA-9的表达及其负性调控BAG4对胃癌细胞增殖与侵袭的影响  

The expression of microRNA-9 and its negative regulation of BAG4 on the proliferation and invasion of gastric cancer cells

作　　者：王军[1] 陈燕[2] 闵光涛[1] 朱俊亚 吕坤 乐奇 姜雷[1] WANG Jun;CHEN Yan;MIN Guangtao;ZHU Junya;LU Kun;LE Qi;JIANG Lei(Department of General Surgery,the First Hospital of Lanzhou University,Lanzhou 730000,China;Department of Stomatology,the First Hospital of Lanzhou University,Lanzhou 730000,China;the First School of Clinical Medicine of Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学第一医院普通外科,甘肃兰州730000 [2]兰州大学第一医院口腔科,甘肃兰州730000 [3]兰州大学第一临床医学院,甘肃兰州730000

出　　处：《中国普通外科杂志》2024年第8期1264-1273,共10页China Journal of General Surgery

基　　金：国家自然科学基金资助项目(82060527);兰州大学第一医院院内基金资助项目(ldyyyn2019-02);甘肃省兰州市科技发展指导性计划基金资助项目(2020-ZD-66)。

摘　　要：背景与目的:研究显示,microRNA-9(miR-9)在多种恶性肿瘤中表达下调,但其在胃癌中的表达情况及功能尚有待明确。笔者前期通过生物信息学方法预测Bcl-2相关永生基因4(BAG4)可能是miR-9的靶基因,并且发现BAG4在胃癌组织中呈高表达。因此,本研究探讨miR-9在胃癌中的表达与功能,及其与BAG4的关系。方法:采用qRT-PCR法检测胃癌组织与癌旁组织,以及胃癌细胞系与正常胃黏膜细胞中miR-9的表达水平。分别用miR-9模拟物和miR-9抑制物过表达和敲低胃癌细胞的miR-9后,采用CCK-8法和克隆形成实验检测细胞增殖活性,Transwell侵袭实验检测细胞侵袭能力。荧光素酶报告基因实验分析miR-9和BAG4的靶向关系,并用qRT-PCR法和Western blot检测转染miR-9模拟物和si-BAG4的胃癌细胞中BAG4的表达,以及相关功能实验加以验证。结果:miR-9在胃癌组织(vs.癌旁组织)和胃癌细胞系(vs.正常胃黏膜细胞)中的表达均明显降低(均P<0.05)。miR-9的表达与胃癌患者的肿瘤大小、肿瘤浸润深度、淋巴结转移、远处转移和TNM分期明显有关(均P<0.05)。miR-9高表达胃癌患者的总生存率明显高于miR-9低表达胃癌患者(P=0.028)。胃癌细胞过表达miR-9后,增殖和侵袭能力明显减弱,而敲低miR-9后,增殖和侵袭能力明显增强(均P<0.05)。荧光素酶报告基因实验显示BAG4是miR-9下游的靶基因。转染miR-9模拟物或si-BAG4的胃癌细胞中BAG4的mRNA与蛋白表达均明显降低,而转染miR-9抑制物胃癌细胞中BAG4的mRNA与蛋白表达均明显降低(均P<0.05)。转染si-BAG4的胃癌细胞的增殖与侵袭能力明显降低,同时转染miR-9抑制物可逆转si-BAG4对胃癌细胞增殖和侵袭能力的影响(均P<0.05)。结论:miR-9在胃癌中表达降低,且其表达与胃癌的不良生物学特征密切相关,其作用机制可能通过负性调控BAG4的表达,从而影响胃癌细胞的增殖和侵袭。Background and Aims:Research has shown that microRNA-9(miR-9)is downregulated in various malignant tumors,but its expression and function in gastric cancer remain unclear.In a previous study,we predicted using bioinformatics methods that Bcl-2-associated athanogene 4(BAG4)might be a target gene of miR-9,and we also found that BAG4 is highly expressed in gastric cancer tissues.Therefore,this study investigated the expression and function of miR-9 in gastric cancer and its relationship with BAG4.Methods:The expression levels of miR-9 in gastric cancer tissues and adjacent non-cancerous tissues,as well as in gastric cancer cell lines and normal gastric mucosal cells,were detected using qRT-PCR.After overexpressing and knocking down miR-9 in gastric cancer cells using miR-9 mimics and inhibitors,cell proliferation was assessed using the CCK-8 assay and colony formation assay,and cell invasion was evaluated using a Transwell invasion assay.The targeting relationship between miR-9 and BAG4 was analyzed using a luciferase reporter assay.Then,the expression of BAG4 in gastric cancer cells transfected with miR-9 mimics or si-BAG4 was detected by qRT-PCR and Western blot,and related functional experiments were performed for validation.Results:The expression of miR-9 was significantly lower in gastric cancer tissues(vs.adjacent noncancerous tissues)and gastric cancer cell lines(vs.normal gastric mucosal cells)(all P<0.05).The expression of miR-9 was significantly associated with tumor size,depth of tumor invasion,lymph node metastasis,distant metastasis,and TNM stage in gastric cancer patients(all P<0.05).Patients with high miR-9 expression had a significantly higher overall survival rate than those with low miR-9 expression(P=0.028).Overexpression of miR-9 in gastric cancer cells significantly reduced proliferation and invasion abilities,while miR-9 knockdown significantly enhanced these abilities(both P<0.05).The luciferase reporter assay indicated that BAG4 was a downstream target gene of miR-9.In gastric cancer cells,bo

关 键 词：胃肿瘤 微RNAS Bcl-2相关永生基因4 细胞增殖 肿瘤侵润 

分 类 号：R735.2[医药卫生—肿瘤]