circ_POLA2靶向miR-30c-5p对胃癌细胞增殖、迁移及侵袭的影响

Effects of circ_POLA2 on the proliferation,migration and invasion of gastric cancer cells by targeting miR-30c-5p

目的:探讨circ_POLA2对胃癌细胞增殖、迁移及侵袭的影响及其可能作用机制。方法:qRT-PCR法检测胃癌组织与癌旁组织中circ_POLA2、miR-30c-5p的表达量;Pearson法分析circ_POLA2与miR-30c-5p在胃癌组织中表达量的相关性;体外培养人胃癌细胞HGC-27,根据转染物不同进行分组:si-NC组、si-circ_POLA2组、miR-NC组、miR-30c-5p组、si-circ_POLA2+NC-inhibitor组、si-circ_POLA2+miR-30c-5p-inhibitor组;CCK-8法、Transwell实验依次检测细胞增殖及迁移、侵袭;双荧光素酶实验检测miR-30c-5p与circ_POLA2的靶向关系;免疫印迹法检测蛋白PI3K、p-PI3K、Akt、p-Akt、MMP-2、MMP-9表达。结果:与癌旁组织比较,胃癌组织中circ_POLA2的表达量升高,miR-30c-5p的表达量降低;circ_POLA2与miR-30c-5p的表达呈负相关;与si-NC组比较,si-circ_POLA2组miR-30c-5p的表达量升高,细胞存活率、基质金属蛋白酶(MMP)-2、MMP-9水平和p-PI3K/PI3K、p-Akt/Akt比值以及迁移、侵袭细胞数均降低;miR-30c-5p过表达可抑制野生型circ_POLA2的荧光素酶活性;与miR-NC组比较,miR-30c-5p组的细胞存活率、MMP-2、MMP-9蛋白表达水平和p-PI3K/PI3K、p-Akt/Akt比值以及迁移、侵袭细胞数均降低;与si-circ_POLA2+NC-inhibitor组比较,si-circ_POLA2+miR-30c-5p-inhibitor组的细胞存活率、MMP-2、MMP-9蛋白表达水平和p-PI3K/PI3K、p-Akt/Akt比值以及迁移、侵袭细胞数均升高。结论:干扰circ_POLA2可通过靶向上调miR-30c-5p表达,抑制PI3K/AKT通路的激活,进而抑制胃癌细胞增殖、迁移及侵袭。

Objective:To explore the effect of circ_POLA2 on the proliferation,migration and invasion of gastric cancer cells and its possible mechanism.Methods:qRT-PCR was used to detect the expression of circ_POLA2 and miR-30c-5p in gastric cancer tissues and adjacent tissues.Pearson analysis was used to analyze the correlation between circ_POLA2 and miR-30c-5p expression in gastric cancer tissues.Human gastric cancer cells HGC-27 were cultured in vitro and grouped according to different transfectants:si-NC group,si-circ_POLA2 group,miR-NC group,miR-30c-5p group,si-circ_POLA2+NC-inhibitor group and si-circ_POLA2+miR-30c-5p-inhibitor group.CCK-8 method and transwell experiments were respectively used to detect cell proliferation,migration and invasion capabilities.The dual luciferase reporter experiment was used to detect the effect of miR-30c-5p overexpression on wild-type and mutant circ_POLA2 luciferase activity.Western blotting was used to detect the expression of PI3K,p-PI3K,Akt,p-Akt,MMP-2 and MMP-9.Results:Compared with adjacent tissues,the expression of circ_POLA2 in gastric cancer tissues was increased,while the expression of miR-30c-5p was decreased.Circ_POLA2 was negatively correlated with miR-30c-5p.Compared with the si-NC group,the expression of miR-30c-5p in the si-circ_POLA2 group was increased,and cell survival rate,the protein levels of MMP-2 and MMP-9,the ratio of p-PI3K/PI3K,p-Akt/Akt,and the number of migrating and invading cells were decreased.Overexpression of miR-30c-5p could inhibit the luciferase activity of wild-type circ_POLA2.Compared with the miR-NC group,the cell survival rate and the protein levels of MMP-2,MMP-9,the ratio of p-PI3K/PI3K,p-Akt/Akt,and the number of migrating and invading cells in the miR-30c-5p group were decreased.Compared with the si-circ_POLA2+NC-inhibitor group,the cell survival rate,the protein levels of MMP-2,MMP-9,the ratio of p-PI3K/PI3K,p-Akt/Akt and the number of migrating and invading cells in the si-circ_POLA2+miR-30c-5p-inhibitor group were increased.Conclusion:Interfering with circ_POLA2 can inhibit the activation of PI3K/Akt pathway by targeting the up-regulation of miR-30c-5p expression,and inhibiting the proliferation,migration and invasion of gastric cancer cells.