Liou S H, Lung J C, Chen Y H, Yang T, Hsieh L L, Chen C J, Wu T N
Department of Public Health, National Defense Medical Center, Taipei, Taiwan, Republic of China.
Cancer Res. 1999 Apr 1;59(7):1481-4.
To examine whether biomarkers such as sister chromatid exchanges (SCEs) and chromosome aberrations (CAs) can predict cancer development, a nested case-control study was performed in a blackfoot endemic area with a known high cancer risk. A cohort of 686 residents was recruited from three villages in the blackfoot endemic area. Personal characteristics were collected, and venous blood was drawn for lymphocyte culture and stored in a refrigerator. The vital status and cancer development were followed using the National Death Registry, Cancer Registry, and Blackfoot Disease Registry. The follow-up period was from August 1991 to July 1995. During this 4-year period, 31 residents developed various types of cancer. Blood culture samples from nine of these subjects were unsuitable for experiments due to improper storage. Finally, a total of 22 cancer cases had cytogenetic samples that could be analyzed. Twenty-two control subjects were selected from those who did not develop cancer in the study period, and these subjects were matched to cases by sex, age, smoking habits, and residential area. The results showed that there was no significant difference in the frequencies of SCE and chromatid-type CAs between the case and control groups. However, the frequencies of chromosome-type CAs, e.g., chromosome-type gaps, chromosome-type breaks, chromosome-type breaks plus exchanges, total chromosome-type aberrations, and total frequencies of CAs in the case group, were significantly higher than those in the control group (P < 0.05). The odds ratio of cancer risk in subjects with more than zero chromosome-type breaks was 5.0 (95% confidence interval = 1.09-22.82) compared to those with zero chromosomal breaks. The odds ratios for more than zero chromosome-type breaks plus exchanges and a frequency of total chromosome-type aberrations of >1.007% were 11.0 and 12.0, respectively (P < 0.05). Subjects with a total CA frequency of >4.023% had a 9-fold increase for cancer risk. These results indicate that chromosome-type CAs are good biomarkers for the prediction of cancer development, whereas SCEs and chromatid-type CAs cannot predict cancer risk.
为了研究诸如姐妹染色单体交换（SCEs）和染色体畸变（CAs）等生物标志物是否能够预测癌症的发生，在一个已知癌症高风险的黑脚病流行地区开展了一项巢式病例对照研究。从黑脚病流行地区的三个村庄招募了686名居民。收集了个人特征信息，并采集静脉血用于淋巴细胞培养，之后储存在冰箱中。通过国家死亡登记处、癌症登记处和黑脚病登记处追踪研究对象的生命状态和癌症发生情况。随访期为1991年8月至1995年7月。在这4年期间，有31名居民患上了各种类型的癌症。其中9名受试者的血培养样本因储存不当而不适用于实验。最终，共有22例癌症病例的细胞遗传学样本可供分析。从研究期间未患癌症的人群中选取了22名对照对象，这些对照对象在性别、年龄、吸烟习惯和居住地区方面与病例进行了匹配。结果显示，病例组和对照组之间SCE和染色单体型CAs的频率没有显著差异。然而，病例组中染色体型CAs的频率，例如染色体型裂隙、染色体型断裂、染色体型断裂加交换、总染色体型畸变以及CAs的总频率，均显著高于对照组（P < 0.05）。与染色体断裂数为零的受试者相比，染色体型断裂数大于零的受试者患癌风险的比值比为5.0（95%置信区间 = 1.09 - 22.82）。染色体型断裂加交换数大于零且总染色体型畸变频率>1.007%的比值比分别为11.0和12.0（P < 0.05）。总CA频率>4.023%的受试者患癌风险增加了9倍。这些结果表明，染色体型CAs是预测癌症发生的良好生物标志物，而SCEs和染色单体型CAs不能预测癌症风险。
