title: Estradiol increases IRS-1 gene expression and insulin signaling in breast cancer cells.
abstract: This study demonstrates how the potentiating effects of E2 on insulin signaling in ER-positive breast cancer cells are consequent to an enhanced IRS-1 expression [corrected]. It induces an increase of both PI-3K/AKT and ERK1/2 activities. A direct action of E2 in the regulating mouse IRS-1 gene is also investigated in both Chinese hamster ovary and MCF-7 cells that are transfected with mouse IRS-1 regulatory sequences. The authors have reported, for the first time, how E2 induction of IRS-1 mRNA was correlated with a direct positive regulatory role of E2 on the IRS-1 promoter. This effect seems to be not strictly related to the cell type.
authors.affiliation: Department of Cellular Biology, University of Calabria, Rende, CS, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Mauro
authors.forename: M
authors.initials: M
authors.lastname: Salerno
authors.forename: M L
authors.initials: ML
authors.lastname: Panno
authors.forename: D
authors.initials: D
authors.lastname: Bellizzi
authors.forename: D
authors.initials: D
authors.lastname: Sisci
authors.forename: A
authors.initials: A
authors.lastname: Miglietta
authors.forename: E
authors.initials: E
authors.lastname: Surmacz
authors.forename: S
authors.initials: S
authors.lastname: Andò
mesh_terms: D000704:Analysis of Variance; D001943:Breast Neoplasms; D004958:Estradiol / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007328:Insulin / Q000502:physiology*; D055504:Insulin Receptor Substrate Proteins; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011401:Promoter Regions, Genetic / Q000187:drug effects* / Q000235:genetics; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism
chemical_list: C526292:IRS1 protein, human; D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; C526295:Irs1 protein, mouse; D010750:Phosphoproteins; D012333:RNA, Messenger; D014443:Tyrosine; D004958:Estradiol