Shaohui Zhang1, Xinguo Liu1, Jianming Liu1, Heng Guo1, Hongfeng Xu1, Geng Zhang2. 1. Department of Pharmacology, Wuhan No. 1 Hospital, Tongji Medical College, Wuhan, Hebei Province, 430030, China. 2. Department of Pharmacology, Wuhan No. 1 Hospital, Tongji Medical College, Wuhan, Hebei Province, 430030, China. Electronic address: geng_zhang@aol.com.
Abstract
BACKGROUND: In this study, we explored the functional mechanism of PPARg co-activator 1-alpha (PGC-1α) in regulating miR-217-mediated breast cancer development in vitro. METHODS: Dual-luciferase activity assay was applied to examine the binding of miR-217 on PGC-1α gene. Breast cancer cell lines, MCF-7 and MDA-MB-231 were infected by lentivirus to constitutively downregulate miR-217. Its regulation on PGC-1α expression was investigated by qRT-PCR and western blot. PGC-1α gene was subsequently downregulated by siRNA in miR-217-downregulated breast cancer cells to examine its effect on cancer proliferation and cell-cycle progression. In addition, another downstream target gene of miR-217, DACH1, was further downregulated in breast cancer cells to investigate the functional association of PGC-1α and DACH1 in miR-217-mediated breast cancer regulation. RESULTS: PGC-1α gene was directly bound by human miR-217. Downregulation of miR-217 in MCF-7 and MDA-MB-231 cells increased PGC-1α production at both mRNA and protein levels. SiRNA-mediated PGC-1α downregulation reversed the inhibition of miR-217-downregulaiton on breast cancer proliferation and cell-cycle progression. Moreover, siRNA-mediated DACH1 downregulation further reversed miR-217-downregulaiton induced inhibition on cancer proliferation and cell-cycle progression in PGC-1α downregulated MCF-7 and MDA-MB-231 cells. CONCLUSION: MiR-217 is the upstream regulator of PGC-1α in breast cancer regulation in vitro, possibly independent of DACH1 signaling pathway.
BACKGROUND: In this study, we explored the functional mechanism of PPARg co-activator 1-alpha (PGC-1α) in regulating miR-217-mediated breast cancer development in vitro. METHODS: Dual-luciferase activity assay was applied to examine the binding of miR-217 on PGC-1α gene. Breast cancer cell lines, MCF-7 and MDA-MB-231 were infected by lentivirus to constitutively downregulate miR-217. Its regulation on PGC-1α expression was investigated by qRT-PCR and western blot. PGC-1α gene was subsequently downregulated by siRNA in miR-217-downregulated breast cancer cells to examine its effect on cancer proliferation and cell-cycle progression. In addition, another downstream target gene of miR-217, DACH1, was further downregulated in breast cancer cells to investigate the functional association of PGC-1α and DACH1 in miR-217-mediated breast cancer regulation. RESULTS: PGC-1α gene was directly bound by humanmiR-217. Downregulation of miR-217 in MCF-7 and MDA-MB-231 cells increased PGC-1α production at both mRNA and protein levels. SiRNA-mediated PGC-1α downregulation reversed the inhibition of miR-217-downregulaiton on breast cancer proliferation and cell-cycle progression. Moreover, siRNA-mediated DACH1 downregulation further reversed miR-217-downregulaiton induced inhibition on cancer proliferation and cell-cycle progression in PGC-1α downregulated MCF-7 and MDA-MB-231 cells. CONCLUSION:MiR-217 is the upstream regulator of PGC-1α in breast cancer regulation in vitro, possibly independent of DACH1 signaling pathway.
Authors: Zhifan Zuo; Tingsong Chen; Yue Zhang; Lei Han; Bo Liu; Bin Yang; Tao Han; Zhendong Zheng Journal: Am J Transl Res Date: 2021-12-15 Impact factor: 4.060