CYP3A4 and cancer: Pro-inflammatory cytokines and acute-phase reactants are elevated in many patients with advanced cancer (Heys et al, 1998; Martin et al, 1999) and there is, therefore, the possibility that part of the inter-individual variability in drug clearance and toxicity could relate to the effects of these cytokines on CYP3A expression (Moreno et al, 1991; Craig et al, 1993; Chen et al, 1994; Muntane-Relat et al, 1995; Morgan, 1997; Pascussi et al, 2000).