Effects of BRCA1 on EGFR expression. A–D, relative EGFR mRNA levels after the overexpression or knockdown of BRCA1 in 293 T cells, human SKOV3 ovarian cancer cells, and primary non-mutated and BRCA1-mutated ovarian cancer cells. Bar graphs show mean ± SD. * P < 0.05 vs. normal. Sh, short hairpin RNAs; Op, overexpression.