In this proposal we provide a rationale for continued infrastructure support for two established, population based cancer epidemiology cohorts that enrolled 81,501 Chinese men and women at baseline in the late 1980s in Shanghai and in the early 1990s in Singapore. Infrastructure support is needed to accrue an additional 2,700 new cancer cases over the next five years to accomplish the overall goal of conducting innovative research that evaluates how environmental and lifestyle exposures, and genetic susceptibility together affect cancer incidence, mortality and aging-related outcomes. In addition to collecting questionnaire information, these two Asian cohorts include an established biorepository with blood, buccal and urine samples from more than 50,000 participants. With the vigorous follow-up procedures in place, only 1.5 percent of the original cohort participants have been lost to follow-up. To date, approximately 17 percent of the cohort members were diagnosed with incident cancers; approximately 50 percent of the cancer patients have stored biospecimens. Researches evaluating the unique environmental and lifestyle exposures of the Asian cohort study populations have provided novel findings that contributed to the field of cancer etiology and prevention. These novel findings in part provided the rationale for our current chemoprevention trials in U.S. populations. During the next 5-year study period, we propose to: (1) Conduct core infrastructure activities to maintain and enhance the two Asian cohort databases, including: (a) follow-up for cancer, non-cancer and death outcomes, (b) maintenance of the biorepositories, and (c) management of the databases; (2) Conduct in-person and telephone interviews among cohort participants to update exposure and medical information; (3) Collect blood and urine samples from cohort participants with cancer diagnoses; and (4) Engage in collaborative research projects of the NCI and Asian Consortium Consortia. We anticipate that the established resources of the two Asian cohorts will become even more scientifically valuable over the next five years as the younger members of the cohorts enter into the age of maximal cancer incidence, thereby increasing the number of pre-disease biomarker-based research projects. RELEVANCE: We are requesting infrastructure support for two established, population-based cancer epidemiology cohorts among Chinese men and women. The unique exposures and cancer risl< profiles of the Asian cohorts have been essential to identifying the protective effect of specific dietary factors on cancer risk. These important findings have been used as a rationale for conducting cancer chemoprevention trials in U.S. populations.