Cai Guiju, Wang Yuejiao, Houda Tahiri, Yang Chun, Wang Lijuan, Gu Muqing, Mueck Alfred, Croteau Stephane, Ruan Xiangyan, Hardy Pierre
Research Center of CHU Sainte-Justine, University of Montréal, 3175 Côte-Sainte-Catherine, Room 2.17.004, Montréal, Québec, Canada; Department of Gynecological Endocrinology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
Research Center of CHU Sainte-Justine, University of Montréal, 3175 Côte-Sainte-Catherine, Room 2.17.004, Montréal, Québec, Canada.
Transl Oncol. 2021 Jun;14(6):101068. doi: 10.1016/j.tranon.2021.101068. Epub 2021 Mar 14.
Research suggests that hormone replacement therapy may increase the risk of breast cancer, and progestins such as norethisterone (NET) play a key role in this phenomenon. We have demonstrated that microRNA-181a (miR-181a) suppresses NET-promoted breast cancer cell survival. Nonetheless, the effects of NET and miR-181a on the tumorigenesis of human breast epithelial cells have not yet been elaborated.
Assays of cell viability, proliferation, migration, apoptosis, and colony formation were performed to investigate the pro-tumorigenesis effect of NET and the effects of miR-181a on human breast epithelial MCF10A cells. The expressions of cell-proliferation-related genes and apoptotic factors were analyzed by quantitative RT-PCR and Western blot in MCF10A cells treated with NET and miR-181a.
NET significantly increased MCF10A cell viability, proliferation, migration, and colony formation, but reduced cellular apoptosis. In addition, NET increased the expression of progesterone receptor membrane component 1 (PGRMC1), EGFR, B-cell lymphoma 2, cyclin D1, and proliferating cell nuclear antigen, but decreased the expression of pro-apoptosis factors, such as Bax, caspase-7, and caspase-9. Overexpression of miR-181a strongly inhibited the effects of NET on MCF10A cells and abrogated NET-stimulated PGRMC1, EGFR, and mTOR expression.
Activation of the PGRMC1/EGFR-PI3K/Akt/mTOR signaling pathway is the primary mechanism underlying the pro-tumorigenesis effects of NET on human breast epithelial MCF10A cells. Additionally, miR-181a can suppress the effects of NET on these cells. These data suggest a therapeutic potential for miR-181a in reducing or preventing the risk of breast cancer in hormone replacement therapy using NET.
研究表明，激素替代疗法可能会增加患乳腺癌的风险，而炔诺酮（NET）等孕激素在这一现象中起关键作用。我们已经证明，微小RNA-181a（miR-181a）可抑制NET促进的乳腺癌细胞存活。尽管如此，NET和miR-181a对人乳腺上皮细胞肿瘤发生的影响尚未阐明。
进行细胞活力、增殖、迁移、凋亡和集落形成分析，以研究NET的促肿瘤发生作用以及miR-181a对人乳腺上皮MCF10A细胞的影响。在用NET和miR-181a处理的MCF10A细胞中，通过定量逆转录-聚合酶链反应和蛋白质免疫印迹分析细胞增殖相关基因和凋亡因子的表达。
NET显著提高了MCF10A细胞的活力、增殖、迁移和集落形成能力，但减少了细胞凋亡。此外，NET增加了孕激素受体膜成分1（PGRMC1）、表皮生长因子受体（EGFR）、B细胞淋巴瘤2、细胞周期蛋白D1和增殖细胞核抗原的表达，但降低了促凋亡因子如Bax、半胱天冬酶-7和半胱天冬酶-9的表达。miR-181a的过表达强烈抑制了NET对MCF10A细胞的作用，并消除了NET刺激的PGRMC1、EGFR和雷帕霉素靶蛋白（mTOR）的表达。
PGRMC1/EGFR-PI3K/Akt/mTOR信号通路的激活是NET对人乳腺上皮MCF10A细胞促肿瘤发生作用的主要机制。此外，miR-181a可以抑制NET对这些细胞的作用。这些数据表明，miR-181a在降低或预防使用NET的激素替代疗法中患乳腺癌风险方面具有治疗潜力。
