Sex differences in improved efficacy of doxorubicin chemotherapy in Cbr1+/- mice.

The anthracycline chemotherapeutic agent doxorubicin is converted by the enzyme carbonyl reductase 1 (CBR1) into its cardiotoxic metabolite doxorubicinol. Cbr1+/- mice have been shown to be protected from doxorubicin-induced cardiotoxicity, and the inhibition of CBR1 activity may be a useful means of ameliorating the side effects of doxorubicin in patients undergoing chemotherapy. Because reduced conversion to doxorubicinol increases circulating levels of the more effective parent drug doxorubicin, it was hypothesized that therapeutic efficacy against tumors might also be enhanced.