7,12-Dimethylbenz[a]anthracene

7,12-Dimethylbenz[a]anthracene (DMBA) is a polycyclic aromatic hydrocarbon (PAH) that has been found in tobacco smoke and diesel exhaust and has carcinogenic activity.{58173,58171} It undergoes metabolic activation by numerous enzymes, including the cytochrome P450 (CYP450) isoform CYP1B1, as well as microsomal epoxide hydrolase (mEH), producing a variety of reactive metabolites that form DNA adducts in vivo, and it has been commonly used to induce tumor formation in various rodent models.{58171,58172,58173} DMBA increases proliferation and migration of, and induces epithelial-to-mesenchymal transition (EMT) in, MCF-10A breast cancer cells when used at a concentration of 5 µM.{58174} It also has immunosuppressant activity, inhibiting proliferation of isolated mouse splenic B- and T cells stimulated ex vivo with LPS or concanavalin A (Item No. 14951), respectively, when administered at doses of 50 and 100 mg/kg.{58175} Intragastric administration of DMBA (20 mg/animal) induces formation of mammary gland tumors in rats.{58176} DMBA (50 µg/animal), in combination with phorbol 12-myristate 13-acetate (TPA; Item No. 10008014), initiates papilloma formation in a rat two-stage model of skin carcinogenesis.{58177}