Molecular epidemiology of breast cancer.

Molecular epidemiology evaluates cancer risk based upon environmental exposures and genetically determined susceptibilities. Biomarkers, molecular indicators of exposure or disease state, are used to stake out the progression of a disease along plausible mechanistic pathways. Connecting biomarkers of exposure, (e.g., carcinogen DNA adducts), effect (e.g., mutations in tumor suppressor genes), or disease (e.g., histological abnormalities) can clarify the etiology of cancer, improve risk estimates, and lead to better preventive strategies. In this review, the following evidence is used to evaluate the possible contribution of environmental carcinogens to breast cancer: a) genetic predispositions in familial breast cancer, b) mutational spectra of the p53 tumor suppressor gene, c) chemical carcinogenesis in breast cancer models, and d) genetic polymorphisms in sporadic breast cancer.