Department of Preventive Medicine, School of Medicine, Kyungpook National University, 101 Dongin-dong, Jung-gu, Daegu, 700-422 Korea.
Mutagenesis. 2010 Sep;25(5):511-6. doi: 10.1093/mutage/geq035. Epub 2010 Jul 8.
Although shortened telomeres have been found in many cancers, elongated telomere length has been observed as an early response after low-dose treatment with various chemical carcinogens in vitro and animal experiments, suggesting low-dose exposure to carcinogenic chemicals may function as a tumour promoter at the very early stage of carcinogenesis in humans. This cross-sectional study was performed to examine whether low-dose exposure to persistent organic pollutants (POPs), lipophilic xenobiotics that mainly bioaccumulate in adipose tissue, is associated with telomere length of peripheral blood leukocytes in apparently healthy persons. Telomere length was measured using quantitative polymerase chain reaction method in 84 apparently healthy Koreans. Among various POPs, serum concentrations of organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs) and polybrominated diphenylethers were measured. Most OC pesticides and PCBs were positively and significantly associated with telomere length with correlation coefficients from about +0.25 to +0.35. The strongest associations were observed with p,p'-dichlorodiphenyldichloroethylene, PCB99, PCB153, PCB180, PCB183 and PCB187. When we examined adjusted means of telomere length by quintiles of POPs, the steeper increases of telomere length tended to be observed within relatively lower ranges of POPs. Besides serum concentrations of POPs, none of the other variables studied, including age, were associated with telomere length in this study. We found that telomere length was increasing across low doses of exposure to POPs in which the majority of study subjects were found, suggesting that low-dose POPs may act as a tumour promoter in carcinogenesis in humans.
虽然在许多癌症中都发现了端粒缩短，但在体外和动物实验中，用各种化学致癌物进行低剂量处理后，观察到端粒长度延长，这表明低剂量接触致癌化学物质可能在人类癌症发生的早期阶段作为肿瘤促进剂发挥作用。本横断面研究旨在检验在表型健康人群中，亲脂性外源性化学物质（主要在脂肪组织中生物累积的持久性有机污染物[POPs]）的低剂量暴露是否与外周血白细胞端粒长度相关。本研究在 84 名表型健康的韩国人中使用实时聚合酶链反应方法测量了端粒长度。在各种 POPs 中，测量了有机氯（OC）农药、多氯联苯（PCBs）和多溴联苯醚的血清浓度。大多数 OC 农药和 PCB 与端粒长度呈正相关且显著相关，相关系数约为+0.25 至+0.35。与 p,p'-二氯二苯二氯乙烯、PCB99、PCB153、PCB180、PCB183 和 PCB187 的相关性最强。当我们根据 POPs 的五分位数检查端粒长度的调整均值时，在相对较低的 POPs 范围内，端粒长度的增加趋势更明显。除了 POPs 的血清浓度外，在这项研究中，没有其他研究变量（包括年龄）与端粒长度相关。我们发现，在大多数研究对象存在的 POPs 低剂量暴露范围内，端粒长度呈递增趋势，这表明低剂量 POPs 可能在人类致癌作用中作为肿瘤促进剂发挥作用。
