Cross-sectional studies of occupational exposures and biomarker endpoints
Cross-sectional studies of healthy exposed and unexposed subjects using biomarker endpoints can identify exposures associated with key characteristics of carcinogens. These studies have been recently recognized by the International Agency for Research on Cancer (IARC) as playing an important role in cancer hazard identification, especially when epidemiologic studies of cancer are inconclusive, or infeasible, when biological plausibility of exposure-cancer associations is needed to help establish causality, or when the exposure of interest has been only recently introduced into the workplace and there has been inadequate latency to study cancer outcomes.
OEEB has a long-standing successful history of performing cross-sectional and short-term
longitudinal molecular epidemiology studies with a focus on organic chemicals (e.g., benzene, trichloroethylene), particulate matter (e.g., diesel exhaust, coal combustion, biomass combustion, e-Waste), pesticides, and biologically active dusts (e.g., endotoxin, glucans). These investigations are conducted in workplaces selected after extensive pilot work and site visits to characterize the work environment, and in study populations with well-characterized exposure histories. These studies generally enroll healthy individuals with a wide range of exposure levels and incorporate high quality, detailed subject-specific exposure data and measurements (air, dermal, and biological measures) that are important for gaining insight into exposure-response relationships and mechanisms of action of suspected and known carcinogens.
Studies evaluating biomarkers linked to occupational and environmental exposures and future risk of cancer in prospective cohorts
OEEB has conducted a series of studies to evaluate the relationship between intermediate biomarkers (e.g., biomarkers of early biologic effect including telomere length, untargeted metabolomic-derived pathways, epigenetic changes, and immune and inflammatory markers) and risk of relevant cancers in prospective cohort studies. IARC has recognized the value of showing that biomarkers used in humans to evaluate the 10 key characteristics of cancer in cross-sectional studies are related to cancer risk as well as to exposure.
View examples of OEEB studies validating biomarkers of cancer risk
Genome Wide Association Studies in Case-Control and Cohort Studies and Evaluation of Gene-Environment Interactions
OEEB has played a leadership role in large-scale, multi-center, international, genome-wide association studies (GWAS) and epigenome-wide association studies (EWAS), including studies of bladder cancer, kidney cancer, prostate cancer, lung cancer among never-smokers, and lymphoid neoplasms. Many of these studies capitalize on the high quality occupational and environmental exposure assessment in OEEB and extramural studies and DCEG expertise in genomics to evaluate gene-environment interactions.
Molecular pathology studies linking occupational and environmental carcinogenic exposures and tumor characteristics
Molecular pathology studies conducted within OEEB integrate histological and molecular tumor tissue profiling with analyses of environmental and genetic risk factors to provide mechanistic insights into cancer etiology. These samples come from case-control studies or, at times, stand-alone case series. OEEB researchers have taken advantage of recent developments and efficiencies in targeted and whole genome DNA sequencing and RNA sequencing and expertise from additional Branches in DCEG to study bladder and kidney cancer tumors, and lung cancer tumors from never-smokers, to link molecular signatures to important exposures.