Cytochrome P450 role in metabolism of drugs and chemicals

A major objective of cancer research is the development of therapeutic agents specifically targeted to tumour cells. Cytochrome P450s expressed at higher levels in the tumour cells than in the surrounding normal tissue offer therapeutic options by the activation of pro-drugs specifically in the cancer cells and avoiding undesirable systemic effects (Riddick et al. 2005). In this respect there are therapeutic options and opportunities arising from both the enhanced endogenous expression of CYP in tumours and CYP-mediated gene therapy. Concerning endogenous overexpression of individual forms of P450 enzymes in tumour cells CYP1B1 is the best-studied example because although several CYP1As CYP2Cs and CY- P3As exhibit enhanced expression in some tumour cells these enzymes display considerable expression in normal tissue mainly in the liver.