Nomura Abraham M Y, Stemmermann Grant N, Lee James, Pollak Michael N
Japan-Hawaii Cancer Study, Kuakini Medical Center, Honolulu, HI 96817, USA.
Am J Epidemiol. 2003 Sep 1;158(5):424-31. doi: 10.1093/aje/kwg176.
Recent reports suggest that colorectal cancer is positively related to insulin-like growth factor I (IGF-I) and inversely related to insulin-like growth factor binding protein 3 (IGFBP-3). To evaluate these associations further and separately for colon and rectal cancer, the authors conducted a nested case-control study in a cohort of 9,345 Japanese-American men examined in Hawaii in 1971-1977. A total of 177 incident colon cancer cases and 105 incident rectal cancer cases were identified from 1972 to 1996. These patients' stored sera and those of 282 age-matched controls were measured for IGF-I and IGFBP-3. The adjusted mean level of IGF-I was higher in colon cancer cases than in controls (154.7 ng/ml vs. 144.4 ng/ml; p = 0.01). However, the multivariate odds ratio for the highest quartile compared with the lowest was just 1.8 (95% confidence interval: 0.8, 4.3). Adjusted mean IGF-I levels were similar between rectal cancer cases and their controls. For IGFBP-3, adjusted mean levels were lower for both colon and rectal cancer cases than for their matched controls, but the differences were not significant. The IGF-I results weakly support findings from other studies and suggest that there are differences in IGF-I findings between colon and rectal cancer cases. It is possible that IGF-related risk is confounded by other factors that may vary among different cohorts. Further research is needed to clarify these relations.
最近的报告表明，结直肠癌与胰岛素样生长因子I（IGF-I）呈正相关，与胰岛素样生长因子结合蛋白3（IGFBP-3）呈负相关。为了进一步分别评估结肠癌和直肠癌与这些因素的关联，作者在1971 - 1977年于夏威夷接受检查的9345名日裔美国男性队列中进行了一项巢式病例对照研究。1972年至1996年期间共确定了177例结肠癌新发病例和105例直肠癌新发病例。对这些患者以及282名年龄匹配的对照者的储存血清进行了IGF-I和IGFBP-3检测。结肠癌病例中IGF-I的校正平均水平高于对照组（154.7 ng/ml对144.4 ng/ml；p = 0.01）。然而，最高四分位数与最低四分位数相比的多变量优势比仅为1.8（95%置信区间：0.8，4.3）。直肠癌病例与其对照组之间的校正平均IGF-I水平相似。对于IGFBP-3，结肠癌和直肠癌病例的校正平均水平均低于其匹配的对照组，但差异不显著。IGF-I的结果对其他研究结果的支持力度较弱，表明结肠癌和直肠癌病例在IGF-I研究结果方面存在差异。IGF相关风险可能被不同队列中可能不同的其他因素所混淆。需要进一步研究来阐明这些关系。
