环状RNA_000926通过靶向miR-411-5p调控宫颈癌细胞的增殖和凋亡

目的： 探讨环状RNA_000926 （circ_000926）对宫颈癌细胞增殖和凋亡的影响及其作用机制。 方法: 收集2019年5月至2020年9月河北医科大学第一医院手术切除的30例宫颈癌患者的癌及癌旁组织标本，以及人宫颈癌细胞HeLa、SiHa和正常宫颈细胞Ect1/E6E7，用qPCR法检测组织和细胞中circ_000926和miR-411-5p的表达水平。将circ_000926过表达质粒及空白质粒、circ_000926小干扰 RNA 及阴性对照寡核苷酸、miR-411-5p mimic 和阴性对照质粒分别转染 HeLa 和 SiHa细胞，分为pc-circ_000926组、pc-NC组、si-circ_000926组、si-NC组、miR-411-5p mimic组和miR-NC组。通过CCK-8法检测转染细胞的增殖活力，TUNEL法检测细胞的凋亡水平。通过双荧光素酶报告基因实验验证circ_000926与miR-411-5p之间的靶向关系，WB法检测细胞中Ki67、BAX、Caspase-3和Caspase-9蛋白的表达。 结果: 与癌旁组织和Ect1/E6E7细胞相比，宫颈癌组织和HeLa、SiHa细胞中circ_000926表达显著升高、miR-411-5p表达显著降低（均P<0.01）。与pc-NC组相比，pc-circ_000926组细胞增殖活力显著增强、细胞凋亡率显著降低（均P<0.01），细胞中miR-411-5p表达显著降低、Ki67蛋白表达显著升高，BAX、Caspase-3、Caspase-9蛋白表达显著降低（均P<0.01）。与si-NC组相比，si-circ_000926组细胞增殖活力显著降低、细胞凋亡率显著升高（均P<0.01），细胞中miR-411-5p表达显著升高、Ki67蛋白表达显著降低，BAX、Caspase-3和Caspase-9蛋白表达显著升高（均P<0.01）。双荧光素酶报告基因实验结果证实circ_000926靶向负向调控miR-411-5p表达，过表达miR-411-5p可逆转过表达circ_000926对宫颈癌细胞增殖和凋亡的作用。 结论: circ_000926通过靶向吸附miR-411-5p促进宫颈癌细胞的增殖，并抑制细胞凋亡。

circRNA_000926 regulates proliferation and apoptosis of cervical cancer cells by targeting miR-411-5p

Objective: To investigate the effects of circular RNA _000926 (circ_000926) on the proliferation and apoptosis of cervical cancer cells and its mechanism. Methods: The tumor tissues and para-cancerous tissues of 30 cervical cancer patients resected in the First Hospital of Hebei Medical University from May 2019 to September 2020 were collected. In addition, human normal cervical cell line ECt1/E6E7 and human cervical cancer cell lines (HeLa and SiHa) were also collected for this study. The expression levels of circ_000926 and miR-411-5p in tissues and cells were detected by qPCR. circ_000926 over-expression plasmids, blank plasmids, circ_000926 small interfering RNA and its negative control oligonucleotide, miR-411-5p mimic and negative control were transfected into HeLa and SiHa cells, respectively, namely pc-circ_000926 group, pc-NC group, si-circ_000926 group, si-NC group, miR-411-5p mimic group and miR-NC group. Cell viability was detected by CCK-8 assay. Cell apoptosis was detected by TUNEL assay. The targeting relationship between circ_000926 and miR-411-5p was verified by Dual-luciferase report gene assay. The protein expression levels of Ki67, BAX, Caspase-3 and Caspase-9 were detected by Western blotting assay. Results: Compared with para-cancerous tissues and normal cervical epithelial Ect1/E6E7 cells, the expression level of circ_000926 was significantly increased while the expression level of miR-411-5p was significantly decreased (all P<0.01) in cervical cancer tissues and HeLa and SiHa cells. Compared with pc-NC group, the cell proliferation viability in pc-circ_000926 group was significantly increased, the apoptosis rate and the expression of miR-411-5p were significantly decreased (all P<0.01), the protein expression of Ki67 was significantly increased(P<0.01), while the protein expression of BAX, Caspase-3 and Caspase-9 was significantly decreased (all P<0.01). Compared with si-NC group, the cell proliferation viability of si-circ_000926 group was significantly decreased (P<0.05), the cell apoptosis rate and the expression of miR-411-5p were significantly increased (all P<0.01), and the protein expression of Ki67 was significantly decreased while the protein expression of BAX, Caspase-3 and Caspase-9 was significantly increased (all P<0.01). Dual-luciferase report gene assay verified that circ_000926 negatively regulated the expression of miR-411-5p, and over-expression of miR-411-5p could reverse the effect of circ_000926 over-expression on the proliferation and apoptosis of cervical cancer cells. Conclusion: circ_000926 can promote the proliferation and inhibit the apoptosis of cervical cancer cells by adsorbing miR-411-5p.