[摘 要] 目的：探讨环状RNA（circRNA）pumilio RNA结合家族成员1（PUM1）调节miR-337-3p/核磷蛋白1（NPM1）轴对子宫 内膜癌（EC）Ishikawa细胞增殖、迁移、侵袭及凋亡的影响。方法：选用Ishikawa细胞，利用RNA干扰技术分别将为sh-circPUM1 及其阴性对照（sh-NC）、anti-miR-337-3p及其阴性对照（anti-NC）质粒转染至Ishikawa细胞，实验分为对照组（未转染细胞）、 sh-NC 组、sh-circPUM1 组、sh-circPUM1 + anti-NC 组、sh-circPUM1 + anti-miR-337-3p 组。qPCR 法检测各组Ishikawa细胞中 circPUM1、miR-337-3p、NPM1 mRNA的表达，CCK-8法、EdU染色法、Transwell小室实验和流式细胞术分别检测敲低circPUM1 对Ishikawa细胞增殖、迁移和侵袭及凋亡的影响，WB法检测Ishikawa细胞中PCNA、NPM1、MMP-9、SNAIL、E-cadherin、 BAX、C-caspase-3蛋白表达变化。双萤光素酶报告基因实验验证circPUM1与miR-337-3p、miR-337-3p与NPM1之间的靶向关 系。结果：与sh-NC组和对照组相比，sh-circPUM1组Ishikawa细胞增殖能力、EdU阳性细胞率、迁移及侵袭细胞数、circPUM1、 NPM1 mRNA及蛋白、PCNA、NPM1、MMP-9和SNAIL蛋白表达均显著降低（均P < 0.05），细胞凋亡率、miR-337-3p，以及 细胞中E-cadherin、BAX和C-caspase-3蛋白表达均显著增加（均P < 0.05）；与sh-circPUM1组、sh-circPUM1 + anti-NC组相比，sh circPUM1 + anti-miR-337-3p组细胞凋亡率、miR-337-3p、E-cadherin、BAX、C-caspase-3蛋白表达均显著降低（均P < 0.05），细胞增 殖能力、EdU阳性细胞率、迁移及侵袭细胞数、NPM1 mRNA及蛋白、PCNA、NPM1、MMP-9和SNAIL蛋白表达均显著升高（均P < 0.05）。circPUM1可靶向负调控miR-337-3p、miR-337-3p可靶向负调控NPM1。结论：敲低circPUM1可以抑制Ishikawa细胞的 恶性生物学行为，其机制可能是通过靶向miR-337-3p/NPM1轴实现的。

[Abstract] Objective: To investigate the effect of circular RNA (cireRNA) pumilio RNA binding family member 1 (PUM1) on the proliferation, migration, invasion and apoptosis of endometrial cancer (EC) Ishikawa cells by regulating the miR-337-3p/ nucleophosmin 1 (NPM1) axis. Methods: Ishikawa cells were selected and plasmid sh-circPUM1 and its negative control (sh-NC), anti-miR-337-3p and its negative control (anti-NC) were transfected into Ishikawa cells by RNA interference. The experiment cells were divided into the control group (non-transfected cells), sh-NC group, sh-circPUM1 group, sh-circPUM1 + anti-NC group and sh-circPUM1 + anti-miR-337-3p group. The qPCR method was applied to detect the expressions of circPUM1, miR-337-3p, and NPM1 mRNA in Ishikawa cells in each group. CCK-8 method, EdU staining method, Transwell assay, and flow cytometry were applied respectively to detect the effects of knocking down circPUM1 on the proliferation, migration, invasion and apoptosis of Ishikawa cells. Western blot was applied to detect the changes in the expressions of PCNA, NPM1, MMP-9, SNAIL, E-cadherin, BAX and C-caspase-3 proteins in Ishikawa cells. Dual luciferase reporter gene experiment was applied to verify the targeting relationship between circPUM1 and miR-337-3p, and between miR-337-3p and NPM1. Results: Cell proliferation ability, EdU positive cell rate, migration and invasion numbers, circPUM1, NPM1 mRNA and protein, the expressions of PCNA, NPM1, MMP-9 and SNAIL protein in Ishikawa cells in the sh-circPUM1 group were significantly lower than those in the sh-NC group and Control group (all P < 0.05); the apoptosis rate, the expressions of miR-337-3p, E-cadherin, BAX, and C-caspase-3 proteins were significantly higher than those in the sh-NC group and the Control group (all P < 0.05). Compared with those in the sh-circPUM1 group and the sh-circPUM1 + anti-NC group, the apoptosis rate, miR-337-3p, the expressions of E-cadherin, BAX, and C-caspase-3 proteins in the sh-circPUM1 + anti-miR 337-3p group were significantly lower (all P < 0.05); Cell proliferation ability, EdU positive cell rate, migration and invasion numbers, NPM1 mRNA and protein, the expressions of PCNA, NPM1, MMP-9, and SNAIL proteins were significantly higher (all P < 0.05). CircPUM1 might target and negatively regulate miR-337-3p, and miR-337-3p might target and negatively regulate NPM1. Conclusion: Knocking down circPUM1 can inhibit the malignant biological behavior of Ishikawa cells, which might be achieved by targeting the miR-337-3p/NPM1 axis.

安徽医科大学2020年度科研基金项目（No. 2020xkj058）