Department of General Surgery, Second Hospital, Shanxi Medical University, Taiyuan, China.
PLoS One. 2012;7(8):e43625. doi: 10.1371/journal.pone.0043625. Epub 2012 Aug 22.
Hypersensitivity to radiation exposure has been suggested to be a risk factor for the development of several malignancies, but not including gastric cancer. In this case-control study, radiation sensitivity as measured by chromatid breaks per cell (b/c) was examined in cultured peripheral blood lymphocytes (PBLs) from 517 patients with gastric cancer and 525 healthy controls. Our results showed that b/c values were significantly higher in cases than in controls (Mean [SD], 0.47 [0.20] vs. 0.34 [0.17]; P<0.001). Using the 50(th) percentile value for controls (0.34 b/c) as the cutoff point, unconditional logistic regression analysis revealed that γ-radiation-sensitive individuals were at significantly higher risk for gastric cancer (adjusted odds ratio [OR] 2.01, 95% confidence interval [CI] 1.49-3.13). Quartile stratification analysis indicated a dose-response relationship between γ-radiation sensitivity and gastric cancer risk (P for trend <0.001). When using the subjects in first quartile of b/c values as reference, the adjusted ORs and corresponding CIs for the subjects in second, third, and fourth quartiles were 1.48 (0.91-2.17), 2.42 (1.76-3.64), and 3.40 (2.11-5.29), respectively. The γ-radiation sensitivity was related to age and smoking status. In addition, a clear joint effect on cancer risk was found between γ-Radiation sensitivity and smoking status. The risk for ever smokers with high sensitivity was higher than those for never smokers with high sensitivity and ever smokers with low sensitivity (OR [CI], 4.67 [2.31-6.07] vs. 2.14 [1.40-3.06] vs. 2.42 [1.57-3.95], respectively). No significant interaction was found between both factors (P for interaction= 0.42). We conclude that chromatid radiosensitivity is associated with gastric cancer susceptibility in a Chinese population.
据报道，对辐射暴露的敏感性是多种恶性肿瘤发展的一个危险因素，但不包括胃癌。在这项病例对照研究中，我们检测了 517 例胃癌患者和 525 例健康对照者培养的外周血淋巴细胞中的染色单体断裂数（b/c），以评估其辐射敏感性。结果显示，病例组的 b/c 值明显高于对照组（均值[标准差]：0.47[0.20]比 0.34[0.17]；P<0.001）。采用对照组第 50 百分位值（0.34 b/c）作为截断值，非条件 logistic 回归分析显示，γ 射线敏感个体患胃癌的风险显著增加（调整比值比[OR] 2.01，95%置信区间[CI] 1.49-3.13）。四分位分层分析表明，γ 射线敏感性与胃癌风险之间存在剂量-反应关系（趋势检验 P<0.001）。当以 b/c 值最低四分位数的个体为参照时，b/c 值处于第二、第三和第四四分位数的个体的调整 OR 及其相应的 95%CI 分别为 1.48（0.91-2.17）、2.42（1.76-3.64）和 3.40（2.11-5.29）。γ 射线敏感性与年龄和吸烟状况有关。此外，还发现γ 射线敏感性与吸烟状况对癌症风险有明显的联合作用。与从不吸烟者或低敏感性吸烟者相比，高敏感性吸烟者的风险更高（OR[CI]：4.67[2.31-6.07]比 2.14[1.40-3.06]比 2.42[1.57-3.95]）。两个因素之间未发现明显的交互作用（交互作用检验 P=0.42）。综上所述，在中国人中，染色体辐射敏感性与胃癌易感性相关。
