Metabolic factors in cancer susceptibility.

The majority of cancers appear to arise from gene mutations induced by chemicals in the environment. Although the resulting metabolic changes which confer the tumour phenotype are still poorly defined, considerable progress has been made in identifying the genes responsible. In addition, there have been significant advances in identifying the genes important in determining the sensitivity of cells to tumorigenic agents. Animal studies clearly demonstrate that individual differences in their expression can lead to profound differences in cancer susceptibility. There is a growing body of evidence that polymorphisms in certain of these genes are also involved in cancer susceptibility in man. This article describes the identification and role of specific metabolic pathways in the tumour initiation and how polymorphisms in their function could relate to cancer susceptibility.