Huang Shirui, Hua Xiaohui, Kuang Mengjiao, Zhu Junlan, Mu Haiqi, Tian Zhongxian, Zheng Xiaoqun, Xie Qipeng
Department of Laboratory Medicine, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, 230032, Anhui, China.
Cancer Cell Int. 2021 Apr 29;21(1):241. doi: 10.1186/s12935-021-01937-5.
Although miR-190 has been reported to be related to human diseases, especially in the development and progression of cancer, its expression in human bladder cancer (BC) and potential contribution to BC remain unexplored.
RT-qPCR was used to verify the expression level of miR-190 and CDKN1B. Flow cytometry (FCM) assays were performed to detect cell cycle. Soft agar assay was used to measure anchorage-independent growth ability. Methylation-Specific PCR, Dual-luciferase reporter assay and Western blotting were used to elucidate the potential mechanisms involved.
Our studies revealed that downregulation of the p27 (encoded by CDKN1B gene) protein is an important event related to miR-190, promoting the malignant transformation of bladder epithelial cells. miR-190 binds directly to CDKN1B 3'-UTR and destabilizes CDKN1B mRNA. Moreover, miR-190 downregulates TET1 by binding to the TET1 CDS region, which mediates hypermethylation of the CDKN1B promoter, thereby resulting in the downregulation of CDKN1B mRNA. These two aspects led to miR-190 inhibition of p27 protein expression in human BC cells. A more in-depth mechanistic study showed that c-Jun promotes the transcription of Talin2, the host gene of miR-190, thus upregulating the expression of miR-190 in human BC cells.
In this study, we found that miR-190 plays an important role in the development of BC. Taken together, these findings indicate that miR-190 may promote the malignant transformation of human urothelial cells by downregulating CDKN1B, which strengthens our understanding of miR-190 in regulating BC cell transformation.
尽管已有报道称miR-190与人类疾病相关，尤其是在癌症的发生和发展过程中，但其在人类膀胱癌（BC）中的表达及其对BC的潜在作用仍未得到探索。
采用逆转录定量聚合酶链反应（RT-qPCR）验证miR-190和周期蛋白依赖性激酶抑制剂1B（CDKN1B）的表达水平。运用流式细胞术（FCM）检测细胞周期。采用软琼脂试验测定非锚定依赖生长能力。通过甲基化特异性聚合酶链反应、双荧光素酶报告基因检测和蛋白质印迹法阐明其中涉及的潜在机制。
我们的研究表明，p27（由CDKN1B基因编码）蛋白的下调是与miR-190相关的重要事件，可促进膀胱上皮细胞的恶性转化。miR-190直接与CDKN1B 3'-非翻译区（UTR）结合，使CDKN1B信使核糖核酸（mRNA）不稳定。此外，miR-190通过与TET1编码区（CDS）结合下调TET1，TET1介导CDKN1B启动子的高甲基化，从而导致CDKN1B mRNA下调。这两个方面导致miR-190抑制人BC细胞中p27蛋白的表达。更深入的机制研究表明，c-Jun促进miR-190宿主基因Talin2的转录，从而上调人BC细胞中miR-190的表达。
在本研究中，我们发现miR-190在BC的发生发展中起重要作用。综上所述，这些发现表明miR-190可能通过下调CDKN1B促进人尿路上皮细胞的恶性转化，这加深了我们对miR-190在调节BC细胞转化中的理解。
