Dehydroepiandrosterone Activation of G-protein-coupled Estrogen Receptor Rapidly Stimulates MicroRNA-21 Transcription in Human Hepatocellular Carcinoma Cells
2015; Elsevier BV; Volume: 290; Issue: 25 Linguagem: Inglês
10.1074/jbc.m115.641167
ISSN1083-351X
AutoresYun Teng, Brandie N. Radde, Lacey M. Litchfield, Margarita M. Ivanova, Russell A. Prough, Barbara J. Clark, Mark A. Doll, David W. Hein, Carolyn M. Klinge,
Tópico(s)Hormonal Regulation and Hypertension
ResumoLittle is known about the regulation of the oncomiR miR-21 in liver. Dehydroepiandrosterone (DHEA) regulates gene expression as a ligand for a G-protein-coupled receptor and as a precursor for steroids that activate nuclear receptor signaling. We report that 10 nm DHEA increases primary miR-21 (pri-miR-21) transcription and mature miR-21 expression in HepG2 cells in a biphasic manner with an initial peak at 1 h followed by a second, sustained response from 3–12 h. DHEA also increased miR-21 in primary human hepatocytes and Hep3B cells. siRNA, antibody, and inhibitor studies suggest that the rapid DHEA-mediated increase in miR-21 involves a G-protein-coupled estrogen receptor (GPER/GPR30), estrogen receptor α-36 (ERα36), epidermal growth factor receptor-dependent, pertussis toxin-sensitive pathway requiring activation of c-Src, ERK1/2, and PI3K. GPER antagonist G-15 attenuated DHEA- and BSA-conjugated DHEA-stimulated pri-miR-21 transcription. Like DHEA, GPER agonists G-1 and fulvestrant increased pri-miR-21 in a GPER- and ERα36-dependent manner. DHEA, like G-1, increased GPER and ERα36 mRNA and protein levels. DHEA increased ERK1/2 and c-Src phosphorylation in a GPER-responsive manner. DHEA increased c-Jun, but not c-Fos, protein expression after 2 h. DHEA increased androgen receptor, c-Fos, and c-Jun recruitment to the miR-21 promoter. These results suggest that physiological concentrations of DHEA activate a GPER intracellular signaling cascade that increases pri-miR-21 transcription mediated at least in part by AP-1 and androgen receptor miR-21 promoter interaction.Background:MicroRNA-21 (miR-21) is an oncomiR in human hepatocellular carcinoma and is highly expressed in liver, but its regulation is uncharacterized.Results:Dehydroepiandrosterone (DHEA) rapidly increases miR-21 transcription in HepG2 cells by activating G-protein-coupled estrogen receptor (GPER).Conclusion:miR-21 transcription is regulated by DHEA through GPER.Significance:GPER may be among the activators of miR-21 expression in human hepatocellular carcinoma. Little is known about the regulation of the oncomiR miR-21 in liver. Dehydroepiandrosterone (DHEA) regulates gene expression as a ligand for a G-protein-coupled receptor and as a precursor for steroids that activate nuclear receptor signaling. We report that 10 nm DHEA increases primary miR-21 (pri-miR-21) transcription and mature miR-21 expression in HepG2 cells in a biphasic manner with an initial peak at 1 h followed by a second, sustained response from 3–12 h. DHEA also increased miR-21 in primary human hepatocytes and Hep3B cells. siRNA, antibody, and inhibitor studies suggest that the rapid DHEA-mediated increase in miR-21 involves a G-protein-coupled estrogen receptor (GPER/GPR30), estrogen receptor α-36 (ERα36), epidermal growth factor receptor-dependent, pertussis toxin-sensitive pathway requiring activation of c-Src, ERK1/2, and PI3K. GPER antagonist G-15 attenuated DHEA- and BSA-conjugated DHEA-stimulated pri-miR-21 transcription. Like DHEA, GPER agonists G-1 and fulvestrant increased pri-miR-21 in a GPER- and ERα36-dependent manner. DHEA, like G-1, increased GPER and ERα36 mRNA and protein levels. DHEA increased ERK1/2 and c-Src phosphorylation in a GPER-responsive manner. DHEA increased c-Jun, but not c-Fos, protein expression after 2 h. DHEA increased androgen receptor, c-Fos, and c-Jun recruitment to the miR-21 promoter. These results suggest that physiological concentrations of DHEA activate a GPER intracellular signaling cascade that increases pri-miR-21 transcription mediated at least in part by AP-1 and androgen receptor miR-21 promoter interaction. MicroRNA-21 (miR-21) is an oncomiR in human hepatocellular carcinoma and is highly expressed in liver, but its regulation is uncharacterized. Dehydroepiandrosterone (DHEA) rapidly increases miR-21 transcription in HepG2 cells by activating G-protein-coupled estrogen receptor (GPER). miR-21 transcription is regulated by DHEA through GPER.
Referência(s)