Department of Surgery, Qingpu Branch of Zhongshan Hospital Affiliated to Fudan University, Shanghai, 201700, China.
Breast Cancer. 2018 Nov;25(6):742-752. doi: 10.1007/s12282-018-0881-5. Epub 2018 Jun 27.
MiRNAs regulate a variety of biological processes, such as cell proliferation and apoptosis and play critical roles in cancer progression. Accumulating studies have demonstrated that miR-1301-3p could regulate the development and progression of multiple cancers, but its biological behaviors in breast cancer (BC) are still elusive.
The expression of miR-1301-3p was determined in BC tissues and cell lines using quantitative real-time PCR analysis. The effects of miR-1301-3p on BC cell growth, proliferation, cell cycle distribution, and apoptosis were also explored in vitro using MTT, colony formation and Flow cytometry assays. The potential target gene of miR-1301-3p was determined by dual-luciferase reporter assay and verified by quantitative real-time PCR and western blot analysis.
We found the expression of miR-1301-3p was observably significantly down-regulated in BC tissues and cell lines. MiR-1301-3p expression in BC tissues was significantly associated with tumor size and clinical stage. Gain-of-function assays demonstrated that miR-1301-3p inhibited the cell growth and proliferation in breast cancer cell lines, MCF-7 and T-47D. Moreover, up-regulation of miR-1301-3p induced cell cycle G0/G1 phase arrest and apoptosis. Mechanistically, up-regulation of miR-1301-3p reduced the expression of CDK4, Cyclin D1, Bcl-2, but elevated the expression of p21, Bad and Bax. ICT1 was confirmed as a direct target of miR-1301-3p. Furthermore, ICT1 overexpression could partially reverse the effects of miR-1301-3p on BC cell proliferation, cell cycle progression and apoptosis.
Our observations suggested that miR-1301-3p inhibits cell proliferation via inducing cell cycle arrest and apoptosis through targeting ICT1, and might be a therapeutic target for BC.
miRNAs 调节多种生物过程，如细胞增殖和凋亡，并在癌症进展中发挥关键作用。越来越多的研究表明，miR-1301-3p 可以调节多种癌症的发展和进展，但它在乳腺癌 (BC) 中的生物学行为仍不清楚。
使用实时定量 PCR 分析检测 BC 组织和细胞系中 miR-1301-3p 的表达。体外采用 MTT、集落形成和流式细胞术检测 miR-1301-3p 对 BC 细胞生长、增殖、细胞周期分布和凋亡的影响。通过双荧光素酶报告基因检测确定 miR-1301-3p 的潜在靶基因，并通过实时定量 PCR 和 Western blot 分析验证。
我们发现 miR-1301-3p 在 BC 组织和细胞系中的表达明显显著下调。BC 组织中 miR-1301-3p 的表达与肿瘤大小和临床分期显著相关。功能获得实验表明，miR-1301-3p 抑制乳腺癌细胞系 MCF-7 和 T-47D 的细胞生长和增殖。此外，上调 miR-1301-3p 诱导细胞周期 G0/G1 期阻滞和细胞凋亡。机制上，上调 miR-1301-3p 降低了 CDK4、Cyclin D1、Bcl-2 的表达，但提高了 p21、Bad 和 Bax 的表达。ICT1 被证实是 miR-1301-3p 的直接靶标。此外，ICT1 的过表达可以部分逆转 miR-1301-3p 对 BC 细胞增殖、细胞周期进程和凋亡的影响。
我们的观察表明，miR-1301-3p 通过靶向 ICT1 诱导细胞周期阻滞和凋亡抑制细胞增殖，可能是 BC 的治疗靶点。
