Mauro L, Salerno M, Panno M L, Bellizzi D, Sisci D, Miglietta A, Surmacz E, Andò S
Department of Cellular Biology, University of Calabria, Rende, CS, Italy.
Biochem Biophys Res Commun. 2001 Nov 2;288(3):685-9. doi: 10.1006/bbrc.2001.5815.
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.
