miR-198在卵巢癌中的表达及对卵巢癌细胞增殖作用的机制研究

The Expression of MiR-198 in Ovarian Cancer and Its Functional Mechanism on the Proliferation of Ovarian Cancer Cells

目的研究微小RNA-198(microRNA-198,miR-198)在卵巢癌中的表达水平及对卵巢癌细胞增殖的影响,并探讨其发挥作用的分子机制。方法采用qRT-PCR检测miR-198在卵巢癌和正常卵巢组织中的表达水平;t检验分析卵巢癌中miR-198的表达水平与患者临床病理参数的关系;Kaplan-Meier生存曲线分析miR-198的表达对癌患者预后的影响;qRT-PCR检测miR-198在卵巢癌细胞SKOV3、CAOV4、CoC1和正常卵巢上皮细胞IOSE80中的表达;选择低表达miR-198的卵巢癌细胞系,转染miR-198模拟物(mimic),分为对照组NC和实验组miR-198 mimic,qRT-PCR检测各组细胞中miR-198的表达水平;MTS实验检测各组细胞的增殖活性;平板克隆检测各组细胞的克隆形成能力;流式细胞仪检测各组细胞的周期比率;Western blotting检测miR-198对增殖周期相关蛋白CDK4、CDK6、cyclinD1和p21表达的影响。结果qRT-PCR结果显示miR-198在卵巢癌中的表达低于正常卵巢组织(t=6.55,P<0.001),且miR-198的表达与患者淋巴结转移和FIGO分期相关(P<0.05);miR-198低表达的卵巢癌患者预后较差(χ^(2)=4.14,P=0.035)。与正常卵巢上皮细胞IOSE80相比,miR-198在卵巢癌细胞SKOV3、CAOV4、CoC1中的表达降低,在SKOV3细胞系中的表达最低(F=59.07,P<0.001)。与对照组NC相比,实验组miR-198 mimic细胞中miR-198的表达增加(t=16.50,P<0.001),miR-198 mimic组细胞增殖活性和克隆形成能力降低及诱导细胞周期阻滞在G0/G1期(P<0.05);与对照组NC相比,miR-198 mimic组细胞中CDK4、CDK6和cyclinD1蛋白表达降低,p21蛋白表达增加(P<0.05)。结论miR-198可能通过调控细胞周期抑制卵巢癌细胞的增殖。miR-198可能是治疗卵巢癌的潜在靶点。

Objective To study the expression level of microRNA-198(miR-198)in ovarian cancer and its effect on the proliferation of ovarian cancer cells,and to explore the molecular mechanism of its role.Methods qRT-PCR was conducted to detect the expression level of miR-198 in ovarian cancer and normal ovarian tissue and t test was applied to analyze the relationship between the expression level of miR-198 in ovarian cancer and the clinical pathological parameters of patients.Kaplan-Meier survival curve analysis was performed to evaluate the effect of miR-198 expression on the prognosis of cancer patients.qRT-PCR was used to detect the expression of miR-198 in ovarian cancer cell lines,including SKOV3,CAOV4,and CoC1,as well as normal ovarian epithelial cells IOSE80.Ovarian cancer cell lines with low miR-198 expression was selected to transfect miR-198 mimics(mimic),and divided into the control group NC and experimental group miR-198 mimic.qRT-PCR was used to detect the expression level of miR-198 in each group of cells.MTS experiment was used to detect the proliferation activity of each group of cells,also plate clone was used to detect the clonogenic ability and flow cytometry was used to detect the cycle ratio.Western blotting was used to detect the effect of miR-198 on the expression of proliferation cycle-related proteins CDK4,CDK6,cyclinD1 and p21.Results qRT-PCR results showed that the expression of miR-198 in ovarian cancer was lower than that in normal ovarian tissues(t=6.55,P<0.001),and the expression of miR-198 was correlated with lymph node metastasis and FIGO staging(P<0.05).Patients with ovarian cancer with low miR-198 expression had poor prognosis(P<0.05).Compared with normal ovarian epithelial cells IOSSE80,the expressions of miR-198 in ovarian cancer cells SKOV3,CAOV4 and CoC1 were reduced,and the expression in SKOV3 cell line was the lowest(F=59.07,P<0.001).Compared with the control group NC,the expression of miR-198 in the experimental group miR-198 mimic cells was increased(t=16.50,P<0.001),and the cell proliferation activity and clone formation ability of the miR-198 mimic group was decreased and induced cell cycle arrest in the G0/G1 phase(P<0.05).Compared with the control group NC,the expression of CDK4,CDK6 and cyclinD1 protein in the miR-198 mimic group were decreased,while the expression of p21 protein was increased(P<0.05).Conclusion Our results show that miR-198 may inhibit the proliferation of ovarian cancer cells by regulating the cell cycle,suggesting that miR-198 may be a potential target for the treatment of ovarian cancer.