title: Formononetin promotes proliferation that involves a feedback loop of microRNA-375 and estrogen receptor alpha in estrogen receptor-positive cells.
abstract: Formononetin is an O-methylated isoflavone that is isolated from the root of Astragalus membranaceus, and it has antitumorigenic effects. Our previous studies found that formononetin triggered growth-inhibitory and apoptotic activities in MCF-7 breast cancer cells. To further investigate the potential effect of formononetin in promoting cell proliferation in estrogen receptor (ER)-positive cells, we used in vivo and in vitro studies to elucidate the possible mechanism. ERα-positive cells (HUVEC, MCF-7) were treated with formononetin. The CCK8 assay, Hoechst 33258, and flow cytometry were used to assess cell proliferation and apoptosis. mRNA levels of ERα, Bcl-2, and miR-375 were quantified using real-time polymerase chain reaction. ERα, p-Akt, and Bcl-2 expression was determined using Western blot. Compared with the control, low formononetin concentrations (2-6 μM) stimulated ERα-positive cell proliferation (HUVEC, MCF-7). The more sensitive HUVEC cells were used to study the relevant signaling pathway. After treatment with formononetin, ERα, miR-375, p-Akt, and Bcl-2 expression was significantly upregulated. The proliferative effect of formononetin was also blocked by a miR-375 inhibitor or raloxifene pretreatment. Additionally, in the in vivo studies, uterine weight in ovariectomized mice treated with formononetin increased significantly, but the weight dramatically decreased with raloxifene or miR-375 inhibitor pretreatment before formononetin. This study demonstrated that formononetin promoted ERα-positive cell proliferation through miR-375 activation and this mechanism is possibly involving in a miR-375 and ERα feedback loop.
authors: School of Basic Medical Sciences, Guilin Medical University, Guilin, China.
authors: Jian
authors: J
authors: Chen
authors: School of Basic Medical Sciences, Guilin Medical University, Guilin, China.
authors: Xing
authors: X
authors: Zhang
authors: School of Basic Medical Sciences, Guilin Medical University, Guilin, China.
authors: Yong
authors: Y
authors: Wang
authors: Department of Emergency, First Affiliated Hospital of Guangxi Medical University, Nanning, China.
authors: Yu
authors: Y
authors: Ye
authors: Department of Pathology, Guilin Medical University, Guilin, China.
authors: Zhaoquan
authors: Z
authors: Huang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D027885:Astragalus propinquus / Q000737:chemistry; D001943:Breast Neoplasms / Q000378:metabolism / Q000517:prevention & control; D049109:Cell Proliferation / Q000187:drug effects*; D047628:Estrogen Receptor alpha / Q000378:metabolism*; D005260:Female; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007529:Isoflavones / Q000737:chemistry / Q000494:pharmacology*; D061986:MCF-7 Cells; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism*; D048789:Phytoestrogens / Q000737:chemistry / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D000972:Antineoplastic Agents, Phytogenic; C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D007529:Isoflavones; C540933:MIRN375 microRNA, human; D035683:MicroRNAs; D048789:Phytoestrogens; C007768:formononetin
keywords: Akt; ERα; HUVEC; formononetin; miR-375