THE SINGAPORE COHORT STUDY OF DIET AND CANCER

这是一项继续资助1993年至1998年期间累积的63 257名中年和老年（45-74岁）新加坡华人男女居民的请求。这项长期的、以人群为基础的队列研究的主要目标是阐明饮食的作用及其与遗传因素在人类癌症病因中的相互作用。在招募时，每名研究受试者都由经过培训的面试官使用结构化问卷亲自面试，该问卷强调通过经验证的165项食物频率问卷评估的当前饮食。从1994年4月开始，随机抽取3%的队列参与者，要求他们提供血液或口腔细胞，以及现场尿液样本。从2000年1月开始，我们将这种生物标本收集扩展到所有存活的队列参与者。截至2004年5月，已联系了所有存活的队列受试者，并从31，318例受试者中采集了生物标本，表示同意率约为60%。我们还要求从1994年4月开始的所有女性乳腺癌和结肠直肠癌病例中采集血液/口腔/尿液样本。迄今为止，有诊断前或诊断后生物标本的癌症病例总数为686例（女性乳腺癌304例，结肠癌223例，直肠癌159例）。在1999年7月至2003年12月期间，再次联系所有存活队列受试者，以获得同意接受电话访谈，更新选定暴露和病史的信息。对52，326名受试者进行了访谈，同意率超过90%。通过与基于人群的新加坡癌症登记处和新加坡出生和死亡登记处的定期记录联系，对该队列的死亡和癌症发生率进行被动随访。队列中观察到的癌症发病率和死亡率与基于新加坡所有华人年龄-性别特异性发病率的相应预期数字相当。我们将继续利用这一队列研究来研究潜在的癌症保护饮食因素，这些因素在研究充分的西方人群中很少食用。我们未来五年的具体目标是：（1）评估茶摄入量在癌症保护中的作用，并考虑喝茶的类型（绿色与红茶）和个体易感性因素，包括控制3种主要排泄途径的关键多态性基因（O-甲基化、葡萄糖醛酸化、硫酸化）;以及（2）评估参与DMA损伤修复和细胞周期调节的基因在改变茶与其他已确定的饮食保护因子之间的给定关联中的潜在作用。和癌症

This is a request for continued funding of a residential cohort of 63,257 middle-aged and older (45-74 years) Singapore Chinese men and women accrued between 1993 and 1998. The primary goal of this long-term, population-based cohort study is to elucidate the role of diet and its interaction with genetic factors in the causation of human cancer. At recruitment, each study subject was interviewed in person by a trained interviewer using a structured questionnaire that emphasized current diet assessed via a validated, 165-item food frequency questionnaire. Beginning in April 1994, a random 3% sample of cohort participants were asked to provide blood or buccal cell, and spot urine samples. We extended this biospecimen collection to all surviving cohort participants starting in January 2000. By May 2004, all surviving cohort subjects had been contacted, and biospecimens were collected from 31,318 subjects, representing a consent rate of about 60%. We also asked for blood/buccal/urine specimens from all incident cases of female breast and colorectal cancers beginning in April 1994. To date, the number of cancer cases with pre- or post-diagnostic biospecimens totals 686 (304 female breast, 223 colon, 159 rectum). Between July 1999 and December 2003, all surviving cohort subjects were recontacted for consent to a telephone interview to update information on selected exposures and medical history. Interviews were completed on 52,326 subjects, representing a consent rate of over 90%. The cohort has been passively followed for death and cancer occurrence through regular record linkage with the population-based Singapore Cancer Registry and the Singapore Registry of Births and Deaths. The observed numbers of incident cancers and deaths within the cohort are comparable to corresponding expected numbers based on age-sex-specific incidence rates for all Chinese in Singapore. We will continue to take advantage of this cohort to examine potential cancer protective dietary factors that are rarely consumed among the well-studied occidental populations. Our specific aims for the next 5 years are: (1) to assess the role of tea intake in cancer protection, with consideration for the type of tea drunk (green vs. black tea) and for individual susceptibility factors including key polymorphic genes controlling the 3 major excretion pathways (O-methylation, glucuronidation, sulfation) for tea polyphenols; and (2) to assess the potential roles of genes involved in repair of DMA damage and in cell cycle regulation in modifying a given association between tea as well as other identified dietary protective factors and cancer.