breast cancer resistance protein


breast cancer resistance protein

A xenobiotic transporter protein encoded by ABCG2 on chromosome 4q22, belonging to the ATP-binding cassette (ABC) superfamily, White subfamily. It plays a major role in multi-drug resistance, and likely serves as a cellular defence mechanism in response to mitoxantrone and anthracycline (daunorubicin and doxorubicin) exposure. It is highly expressed in the placenta, but its role there is unknown.