卵巢癌组织中miR-223的表达及其对卵巢癌OVCAR3细胞增殖和侵袭的促进作用

Expression of miR-223 in ovarian cancer tissue and its promoting effect on proliferation and invasion of ovarian cancer OVCAR3 cells

目的:分析微小RNA-223(miR-223)在卵巢癌组织中的表达情况,探讨miR-223对卵巢癌OVCAR3细胞增殖和侵袭的影响,并阐明其分子调控机制。方法:采用实时荧光定量PCR(RT-qPCR)法检测45例卵巢癌患者手术切除组织样本和不同卵巢癌细胞中miR-223表达水平,分析不同临床病理特征卵巢癌患者癌组织中miR-223表达水平。体外培养卵巢癌OVCAR3细胞,采用生物信息学、双荧光素酶报告基因实验和Western blotting法分析miR-223对N-myc下游调节基因1(NDRG1)的靶向调控关系。OVCAR3细胞分别转染阴性对照模拟物(NC组)、miR-223抑制剂(MiR in组)和同时转染miR-223抑制剂及siRNA-NDRG1质粒(MiR in+si-NDRG1组),克隆形成实验检测各组细胞克隆形成数,流式细胞术检测各组细胞凋亡率,Transwell小室实验检测各组细胞中侵袭细胞数。结果:与癌旁正常组织比较,卵巢癌组织中miR-223表达水平明显升高(P<0.01),miR-223表达水平与卵巢癌患者组织学分化程度、FIGO分期和淋巴结转移有密切关联(P<0.01)。不同卵巢癌细胞中miR-223表达水平均高于正常卵巢上皮细胞(P<0.01)。miR-223可靶向结合NDRG1并抑制NDRG1的表达,且在卵巢癌组织中NDRG1 mRNA表达水平与miR-223表达水平呈负相关关系(r=-0.291,P<0.01)。与NC组比较,MiR in组细胞中克隆形成数和侵袭细胞数均明显减少(P<0.05或P<0.01),细胞凋亡率明显升高(P<0.01);与MiR in组比较,MiR in+si-NDRG1组细胞中克隆形成数和侵袭细胞数明显增加(P<0.05或P<0.01),细胞凋亡率明显降低(P<0.01)。结论:MiR-223在卵巢癌组织中呈高表达,其表达水平与卵巢癌的严重程度有密切关联。miR-223可通过靶向抑制NDRG1表达促进卵巢癌细胞增殖和侵袭,并抑制细胞凋亡。

Objective:To analyze the expression of microRNA-223(miR-223)in the ovarian cancer tissue and explore the effect of miR-223 on the proliferation and invasion of ovarian cancer OVCAR3 cells,and to clarify the molecular regulatory mechanism.Methods:The expression levels of miR-223 in tissue samples taken during surgical removal of 45 patients with ovarian cancer and different ovarian cancer cells were detected by real-time fluorescence quantitative PCR(RT-qPCR)method,and the expression levels of miR-223 in cancer tissue of the ovarian cancer patients with different clinicopathological features were analyzed.The ovarian cancer OVCAR3 cells were cultured in vitro;bioinformatics,dual luciferase reporter gene experiment and Western blotting method were used to analyze the targeted regulation relationship of miR-223 to N-myc downstream regulatory gene 1(NDRG1).The OVCAR3 cells were transfected with negative control mimic(NC group),miR-223 inhibitor(MiR in group)and miR-223 inhibitor and siRNA-NDRG1 plasmid at the same time(MiR in+si-NDRG1 group).The number of clone formation was detected by colony formation test,the apoptotic rate was measured by flow cytometry,and the number of invasion cells was measured by Transwell chamber assay.Results:Compared with adjacent normal tissue the expression level of miR-223 in cancer tissue was significantly increased(P<0.01);the miR-223 expression level was closely related to the degree of histological differentiation,FIGO stage and lymph node metastasis of ovarian cancer patients(P<0.01).Meanwhile,the expression levels of miR-223 in the different ovarian cancer cells were higher than that in normal ovarian epithelial cells(P<0.01).MiR-223 could target NDRG1 and inhibit the expression of NDRG1,and the expression level of NDRG1 mRNA in ovarian cancer tissue was negatively correlated with the expression level of miR-223(r=-0.291,P<0.01).Compared with NC group,the number of clone formation and the number of invasion cells in MiR in group were decreased(P<0.05 or P<0.01),while the apoptotic rate was significantly increased(P<0.01).Compared with MiR in group,the number of clone formation and the number of invasion cells in MiR in+si-NDRG1 group were increased(P<0.05 or P<0.01),while the apoptotic rate was decreased(P<0.01).Conclusion:MiR-223 is highly expressed in the ovarian cancer tissue,which is positively correlated with the severity of ovarian cancer.MiR-223 can promote the proliferation and invasion of ovarian cancer cells and inhibit apoptosis by targeted inhibition of NDRG1 expression.