“Our recent work has shown that cannabidiol (CBD) exhibits the most potent direct inhibition of human cytochrome P450 1A1 (CYP1A1)…

These results suggest that the pentylresorcinol structure in CBD may have structurally important roles in direct CYP1A1 inhibition, although the whole structure of CBD is required for overall inhibition.”

http://www.ncbi.nlm.nih.gov/pubmed/23811569

“CYP1A1 regulates breast cancer proliferation and survival. This study supports the notion that CYP1A1 promotes breast cancer proliferation and survival… reduction of CYP1A1 levels is a potential strategy for breast cancer therapeutics.”  http://www.ncbi.nlm.nih.gov/pubmed/23576571