Foxo3a protein expression in distinct ER+ and ER− breast cell lines.

<p>(A) A Western blot analysis of endogenous Foxo3a abundance in three human breast cancer cell lines and one normal human breast epithelial cell line: MCF-7 (ER+), MDA-MB-435(ER−), MDA-MB-231(ER−) and HBL 100. The total protein extracted from the indicated cell lines was analyzed using a polyclonal antibody against human Foxo3a. β-actin was used as a loading control. (B) The bar graph below demonstrates the level of Foxo3a expression compared with the expression of β-actin. Error bars reflect the standard error from at least 3 independent experiments. * indicates p<0.05 for comparison between MCF-7 and MDA-MB-435 or MDA-MB-231.