Given that aberrant AhR expression and pathway activation are involved in gastric carcinogenesis;17 both CYP1A1 mRNA and protein expression are inducible in gastric cancer; CYP2W1 protein is embryonically expressed in gastrointestinal tissues and highly expressed in gastric cancer;18 we speculate that AhR, CYP1A1 and tumour‐specific CYP2W1 may represent putative molecular targets for anticancer therapy in gastric cancer. This evidence concerns the gene CYP1A1 and neoplasm.