Objective: To explore the regulatory effect of miR-204-5p on biological behaviors of bladder cancer cells and its molecular mechanism.
Methods: Survival analysis and correlation analysis were performed using TCGA database to explore the association of miR-204-5p expression with survival outcomes and clinicopathological parameters of bladder cancer patients. The expression level of miR-204-5p was detected in bladder cancer and adjacent tissues and in normal uroepithelial cells and bladder cancer cells. In cultured bladder cancer cells, the effects of miR-204-5p overexpression and knockdown on cell proliferation, migration, invasion, and apoptosis were analyzed. Transcriptome sequencing, bioinformatics analysis and dual-luciferase assay were carried out to confirm targeted inhibition of RAB22A by miR-204-5p to promote malignant biological behaviors of bladder cancer cells.
Results: Patients with high miR-204-5p expressions had lowered median survival time and poor prognosis (P < 0.05). The expression of miR-204-5p was significantly up-regulated in bladder cancer tissues and cells (P < 0.05). In bladder cancer cells, miR-204-5p overexpression significantly promoted cell proliferation, migration and invasion and reduced cell apoptosis. Transcriptome sequencing, bioinformatics analysis and dual-luciferase assay all suggested that RAB22A was a key downstream factor of miR-204-5p. Overexpression of miR-204-5p significantly inhibited RAB22A expression in bladder cancer cells, and overexpression of RAB22A partially reversed miR-204-5p overexpression-induced enhancement of bladder cancer cell proliferation.
Conclusion: High expression of miR-204-5p promotes proliferation, migration and invasion and reduces apoptosis of bladder cancer cells by negatively regulating RAB22A expression.
目的: 探讨MiR-204-5p靶向RAB22A对膀胱癌细胞生物学行为的影响及其分子机制。
方法: TCGA数据库进行了miR-204-5p的生存分析和临床病理性状的相关性分析；检测膀胱癌组织和癌旁组织以及正常尿路上皮细胞和膀胱癌细胞中miR-204-5p的表达水平；过表达/敲低miR-204-5p后检测细胞增殖、迁移和侵袭、和凋亡等变化；转录组测序，数据库分析和多种实验证实miR-204-5p靶向抑制RAB22A基因调控膀胱癌细胞的生物学行为。
结果: TCGA数据库中MiR-204-5p高表达患者的中位生存期较低，表现出较差的预后（P<0.05）；miR-204-5p在膀胱癌组织和细胞表达明显上调（P<0.05）；过表达miR-204-5p可促进细胞增殖（P<0.05）、迁移和侵袭（P<0.05），减少细胞凋亡（P<0.05），敲低后则相反；转录组测序，数据库分析和双荧光素酶实验提示RAB22A是miR-204-5p下游关键因子，qRT-PCR，Western blotting证实过表达miR-204-5p可抑制RAB22A的表达（P<0.05）；过表达RAB22A可部分逆转miR-204-5p对膀胱癌细胞生长的促进作用（P<0.05）。
结论: miR-204-5p通过靶向负性调控RAB22A促进膀胱癌细胞的恶性生物学行为。
Keywords: RAB22A; bladder cancer; miR-204-5p.