Department of Urology, The Second Hospital of Shandong University, Ji'nan, China.
Eur Rev Med Pharmacol Sci. 2019 Oct;23(20):8813-8822. doi: 10.26355/eurrev_201910_19276.
To investigate the role of microRNA-15 (miR-15) in the progression of bladder cancer (BC) cell and its underlying mechanism.
Human BC specimens were collected from BC patients during operations. BC cell lines (T24, BIU87, and HT1376) and normal uroepithelial cell lines SV-HUV-1 were cultured. The abilities of cell proliferation and invasion were detected by Methyl thiazolyl tetrazolium (MTT) and transwell assay, respectively. Additionally, the relevant mRNA and protein expressions were measured by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), Western blot and immunohistochemistry, respectively. Furthermore, the luciferase reporter assay was used to verify the target gene of miR-15. Besides, Xenograft tumor formation assay was performed to confirm the effect of miR-15 on tumor growth.
A low expression of miR-15 was detected by qRT-PCR, whereas the high expression of B cell-specific Moloney murine leukemia virus integration site 1 (BMI1) was detected by immunocytochemical assay in BC tissues. Moreover, miR-15 expression and BMI1 expression were significantly associated with the overall survival of BC patients. MTT and transwell assay results stated that the up-regulation of miR-15 inhibited BC cell proliferation, migration, and invasion. BMI-1 was verified as a direct target of miR-15 in BC using Luciferase reporter assay. Besides, miR-15 regulated epithelial-mesenchymal transition (EMT)-related makers, protein kinase B (AKT), and the phosphorylation of AKT protein levels in BC using the Western blot assay. Xenograft tumor formation assay indicated that the over-expression of miR-15 inhibited the tumor growth.
We stated that miR-15 suppressed BC cell progression by targeting BMI1 through the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, which provided a potential target for BC treatment.
研究 microRNA-15（miR-15）在膀胱癌（BC）细胞进展中的作用及其机制。
术中收集 BC 患者的 BC 标本。培养 BC 细胞系（T24、BIU87 和 HT1376）和正常尿路上皮细胞系 SV-HUV-1。噻唑蓝（MTT）和 Transwell 检测细胞增殖和侵袭能力。此外，通过定量实时聚合酶链反应（qRT-PCR）、Western blot 和免疫组织化学分别测量相关 mRNA 和蛋白表达。进一步，利用荧光素酶报告基因检测 miR-15 的靶基因。另外，进行异种移植瘤形成实验以验证 miR-15 对肿瘤生长的影响。
qRT-PCR 检测到 miR-15 表达降低，免疫细胞化学检测到 BC 组织中 B 细胞特异性 Moloney 鼠白血病病毒整合位点 1（BMI1）表达升高。此外，miR-15 表达和 BMI1 表达与 BC 患者的总生存率显著相关。MTT 和 Transwell 实验结果表明，上调 miR-15 抑制 BC 细胞增殖、迁移和侵袭。荧光素酶报告基因检测证实 BMI1 是 BC 中的 miR-15 的直接靶基因。此外，Western blot 实验表明 miR-15 通过蛋白激酶 B（AKT）和 AKT 蛋白磷酸化水平调节 EMT 相关标志物在 BC 中的表达。异种移植瘤形成实验表明，miR-15 的过表达抑制了肿瘤的生长。
我们发现 miR-15 通过 PI3K/AKT 信号通路靶向 BMI1 抑制 BC 细胞进展，为 BC 的治疗提供了潜在的靶点。
