[摘 要] 目的：探究环状RNA肌动蛋白束蛋白1（circFSCN1）调节miR-429/非转移性黑色素蛋白B（GPNMB）轴对胃癌细胞恶 性生物学行为的影响及机制。方法：收集2022年9月至2023年9月期间在河北医科大学第一医院手术切除的54例胃癌组织及 相应癌旁组织，用qPCR法检测胃癌组织中circFSCN1、miR-429和GPNMB mRNA的表达。常规培养胃癌细胞MGC803，将其分 为对照组、sh-NC组、sh-circFSCN1组、sh-circFSCN1 + anti-NC组、sh-circFSCN1 + anti-miR-429组。qPCR法各组MGC803细胞中 circFSCN1、miR-429和GPNMB mRNA的表达。CCK-8法、克隆形成实验、Transwell实验和流式细胞术分别检测各组MGC803细 胞的增殖、迁移、侵袭和凋亡。免疫荧光法检测各组细胞中GPNMB蛋白的表达。WB法检测各组MGC803细胞中PCNA、 MMP-2、GPNMB、cleaved caspase-3 蛋白的表达。双萤光素酶报告基因实验和RNA结合蛋白免疫共沉淀（RIP）实验验证 circFSCN1与miR-429和miR-429与GPNMB之间的结合调控关系。结果：circFSCN1、GPNMB mRNA在胃癌组织中均呈高表达 （均P < 0.05），miR-429呈低表达（P < 0.05）。敲减circFSCN1可促进miR-429表达，抑制GPNMB mRNA表达，抑制miR-429则可 促进GPNMB mRNA表达。敲减circFSCN1可显著抑制MGC803细胞的增殖、迁移、侵袭能力，并促进其凋亡，抑制miR-429可部 分逆转敲减circFSCN1的作用。敲减circFSCN1可抑制MGC803细胞中PCNA、MMP-2和GPNMB蛋白表达，抑制cleaved caspase-3蛋白表达，抑制miR-429可部分逆转敲减circFSCN1的作用。circFSCN1与miR-429和miR-429与GPNMB mRNA之间 存在靶向结合负向调控关系。结论：敲减circFSCN1通过miR-429/GPNMB轴抑制胃癌细胞的恶性生物学行为，circFSCN1是胃 癌潜在的治疗靶点。

[Abstract] Objective: To investigate the effects of circular RNA fascin actin-bundling protein 1 (circFSCN1) on the malignant biological behaviors of gastric cancer cells by regulating the microRNA-429 (miR-429)/glycoprotein nonmetastatic melanoma protein B (GPNMB) axis and its mechanisms. Methods: The gastric cancer tissues and corresponding para-cancerous tissues of 54 patients who underwent surgical resection at the First Hospital of Hebei Medical University between September 2022 and September 2023 were collected. The expressions of circFSCN1, miR-429 and GPNMB mRNA in gastric cancer tissues were detected by qPCR. Gastric cancer MGC803 cells were routinely cultured and divided into the control group, the sh-NC group, the sh-circFSCN1 group, the sh-circFSCN1+anti-NC group, and the sh-circFSCN1 + anti-miR-429 group. The expressions of circFSCN1, miR-429 and GPNMB mRNA in MGC803 cells of each group were detected by qPCR. The proliferation, migration, invasion and apoptosis of MGC803 cells in each group were detected by CCK-8 method, colony formation assay, Transwell assay and flow cytometry, respectively. Immunofluorescence was used to detect the expressions of GPNMB protein in cells of each group. WB assay was used to detect the expressions of PCNA, MMP-2, GPNMB and Cleaved Caspase-3 proteins in MGC803 cells of each group. Dual luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay were used to verify the binding regulatory relationship between circFSCN1 and miR-429, and between miR-429 and GPNMB. Results: circFSCN1 and GPNMB mRNA were both highly expressed in gastric cancer tissues (both P < 0.05), while miR-429 was lowly expressed (P < 0.05). Knockdown of circFSCN1 could promote the expression of miR-429 and inhibit the expression of GPNMB mRNA. Inhibition of miR-429 could promote the expression of GPNMB mRNA. Knockdown of circFSCN1 could significantly inhibit the proliferation, migration and invasion abilities of MGC803 cells and promote their apoptosis. Inhibition of miR-429 could partially reverse the effect of circFSCN1 knockdown. Knockdown of circFSCN1 could inhibit the expressions of PCNA, MMP-2 and GPNMB proteins in MGC803 cells and inhibit the expression of cleaved caspase-3 protein. There was a targeted binding and negative regulatory relationship between circFSCN1 and miR-429 and between miR-429 and GPNMB mRNA. Conclusion: Knocking down circFSCN1 inhibits the malignant biological behaviors of gastric cancer cells through the miR-429/GPNMB axis, indicating that circFSCN1 is a potential therapeutic target for gastric cancer.

2022年政府资助临床医学优秀人才培养项目（No. LS202208）