Guo Junsheng, Zhang Jian, Yang Tianxiao, Zhang Wei, Liu Mingyang
Department of Urology, Affiliated Hospital of Chifeng University Chifeng, Inner Mongolia, China.
Int J Clin Exp Pathol. 2020 Mar 1;13(3):587-596. eCollection 2020.
Bladder cancer is a common, serious disease worldwide. MicroRNAs (miRNAs) have been reported to participate in the development and progression in many cancers, including bladder cancer. However, the exact roles of miR-22 in bladder cancer process and its underlying mechanism remain largely unknown. The expression levels of miR-22 and E2F3 were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was used to detect the protein levels of E2F3, E-cadherin, N-cadherin, and Vimentin in bladder cancer cells. Cell viability, proliferation, migration, and invasion were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay, colony formation assay, and transwell assay, respectively. The potential binding sites between miR-22 and E2F3 were predicted by TargetScan and verified by luciferase report assay. The expression of miR-22 was downregulated and E2F3 expression was upregulated in bladder cancer tissues and cells. Overexpression of miR-22 or E2F3 knockdown inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in bladder cancer cells. In addition, E2F3 was a direct target of miR-22 and its knockdown attenuated the promotion of cell proliferation, migration, invasion, and EMT induced by miR-22 inhibitor in bladder cancer cells. In conclusion, miR-22 suppressed cell proliferation, migration, invasion, and EMT in bladder cancer cells by regulating E2F3 expression, providing a novel avenue for treatment of bladder cancer.
膀胱癌是一种在全球范围内常见的严重疾病。据报道，微小RNA（miRNA）参与了包括膀胱癌在内的许多癌症的发生和发展。然而，miR-22在膀胱癌进程中的具体作用及其潜在机制仍 largely未知。通过定量实时聚合酶链反应（qRT-PCR）分析miR-22和E2F3的表达水平。采用蛋白质印迹法检测膀胱癌细胞中E2F3、E-钙黏蛋白、N-钙黏蛋白和波形蛋白的蛋白水平。分别通过3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）法、集落形成试验和Transwell试验测定细胞活力、增殖、迁移和侵袭能力。通过TargetScan预测miR-22与E2F3之间的潜在结合位点，并通过荧光素酶报告试验进行验证。在膀胱癌组织和细胞中，miR-22的表达下调，E2F3的表达上调。miR-22的过表达或E2F3的敲低抑制了膀胱癌细胞的增殖、迁移、侵袭和上皮-间质转化（EMT）。此外，E2F3是miR-22的直接靶点，其敲低减弱了miR-22抑制剂诱导的膀胱癌细胞增殖、迁移、侵袭和EMT的促进作用。总之，miR-22通过调节E2F3的表达抑制膀胱癌细胞的增殖、迁移、侵袭和EMT，为膀胱癌的治疗提供了一条新途径。
