biostudies-literatureUnknown8(1)Nagpal NMediator complex has been extensively shown to regulate the levels of several protein-coding genes; however, its role in the regulation of miRNAs in humans remains unstudied so far. Here we show that MED1, a Mediator subunit in the Middle module of Mediator complex, is overexpressed in breast cancer and is a negative prognostic factor. The levels of several miRNAs (miR-100-5p, -191-5p, -193b-3p, -205-5p, -326, -422a and -425-5p) were found to be regulated by MED1. MED1 induces miR-191/425 cluster in an estrogen receptor-alpha (ER-α) dependent manner. Occupancy of MED1 on estrogen response elements (EREs) upstream of miR-191/425 cluster is estrogen and ER-α-dependent and ER-α-induced expression of these miRNAs is MED1-dependent. MED1 mediates induction of cell proliferation and migration anScientific reports11805https://www.ebi.ac.uk/biostudies/studies/S-EPMC6081450biostudies-literatureEssential role of MED1 in the transcriptional regulation of ER-dependent oncogenic miRNAs in breast cancer.PMC6081450Thakur JKDurante GSharma SNagpal NFerracin MKulshreshtha RMaji SfalseEssential role of MED1 in the transcriptional regulation of ER-dependent oncogenic miRNAs in breast cancer.Mediator complex has been extensively shown to regulate the levels of several protein-coding genes; however, its role in the regulation of miRNAs in humans remains unstudied so far. Here we show that MED1, a Mediator subunit in the Middle module of Mediator complex, is overexpressed in breast cancer and is a negative prognostic factor. The levels of several miRNAs (miR-100-5p, -191-5p, -193b-3p, -205-5p, -326, -422a and -425-5p) were found to be regulated by MED1. MED1 induces miR-191/425 cluster in an estrogen receptor-alpha (ER-α) dependent manner. Occupancy of MED1 on estrogen response elements (EREs) upstream of miR-191/425 cluster is estrogen and ER-α-dependent and ER-α-induced expression of these miRNAs is MED1-dependent. MED1 mediates induction of cell proliferation and migration an2018-01-01T00:00:00Z2018 Aug2025-04-03T22:14:07.085Z2019-03-26T23:50:56ZS-EPMC60814503008736610.1038/s41598-018-29546-9