In cell culture experiments, the treatment with α-naphthoflavone (αNF), a prototype SAhRM, exerted cell line-specific effects: in ERα-negative human UACC-3199 sporadic breast cancer cell line, it rescued BRCA-1 and ERα expression, while inducing CYP1A1; in ERα-positive MCF-7 breast cancer cells, αNF antagonized E2-dependent stimulation of BRCA-1 without affecting ERα expression. This evidence concerns the gene CYP1A1 and breast cancer.