Abstract 46: A review of the gene-environment interaction literature in cancer: What do we know?

Risk of cancer is determined by a complex interplay of genetic and environmental factors. Therefore, the study of gene-environment interactions has been an active area of research for several years. To examine the state of the science in the field of gene-environment interactions research in cancer, we performed a systematic review of the published literature. A total of 3019 articles were identified using the gene-environment or pharmacogenomic flags from the HuGE literature finder and CancerGAMAdb, curated databases of genetic association studies, from January 1, 2001 to January 31, 2010. From these articles, 243 articles were determined to be relevant based on the inclusion criteria of at least 1000 cases in the interaction studied, examining the combination of genes and environment, and investigating the interaction as related to cancer risk. Information from these articles was abstracted regarding cancer type, environmental exposure variables, genetic variables, and estimates of interaction effects. In these papers, over 3500 interactions were investigated. The majority of these interactions were examined in colon, rectal, or colorectal cancer types (40%) followed by breast cancer (30%). Most of these interactions were explored using candidate gene polymorphisms (82%) compared with polymorphisms identified from genome wide association studies (GWAS). The most common environmental exposure categories observed were “energy balance” (41%), e.g. BMI or diet, followed by “Lifestyle” (21%), e.g. smoking or alcohol intake. Further analysis regarding commonly observed interactions, analytical tests performed, number of statistically significant interactions and magnitudes of interactions is on-going. In conclusion, observations of published literature suggest that opportunity exists for more of an agnostic approach to the study of gene-environment interactions and exploring alternative environmental exposures. Citation Format: Leah E. Mechanic, Naoko I. Simonds, Armen Ghazarian, Camilla B. Benedicto, Sheri D. Schully, Gary L. Ellison, Elizabeth M. Gillanders. A review of the gene-environment interaction literature in cancer: What do we know? [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr 46.