Abstract
Drug resistance to conventional chemotherapeutics is a great impediment to cancer therapy. A major part of this problem arises from rapid metabolism of the drugs by cytochrome P450 class of enzymes before they reach their targets or at the target itself. Inhibition of such enzymatic deactivation of the drugs could offer partial rescue and make chemotherapy more effective. Site specific delivery of exogenous carbon monoxide has been shown to inhibit cytochrome P450 enzymes and resurrect sensitivity to chemotherapeutics already available in the market. Successful design for application of such CO delivery will thus be extremely desirable to patients particularly in poor countries where the antibody-based or nanodrug therapies, discovered recently, are too expensive for the general population. The potential of such carbon monoxide-induced cytochrome P450 inhibition to improve drug sensitization to conventional chemotherapeutics in breast cancer therapy has been discussed in this account.