MEK Inhibition Increases ERα Expression in Human Ovarian Carcinoma Cells.

<p>(A) Expression of ERα protein in human ovarian cancer cell lines. MCF-7, a breast cancer cell line was used as positive control. All cell lines were treated with MEKi at 1 uM for 24 h. (B) The effect of estrogen deprivation on cell cycle. Cells were grown in phenol red-free charcoal stripped RPMI for 48 h to simulate ES-free conditions, and subsequently analyzed for cell cycle distribution and doubling time, as described in Materials and Methods. (C) The effect of MEK inhibition for 24 h on ERα expression and MAPK pathway activation in ovarian cancer cells. DMSO was used as the vehicle-only control. (D) Dose-dependent increase in ERα expression in SKOV3 cells by MEKi (24 h); and densitometric quantification relative to GAPDH. (E) Flow cytometric analysis of cell-cycle distribution at various time points indicates G1 arrest 24 h post MEKi treatment in SKOV3 cells.