Department of Population Health Sciences, University of Wisconsin–Madison, Madison, Wisconsin, USA.
Cancer Epidemiol Biomarkers Prev. 2012 Nov;21(11):2095-100. doi: 10.1158/1055-9965.EPI-12-0671. Epub 2012 Oct 23.
Telomeres, the ends of chromosomes, are critical for maintaining genomic stability and grow shorter with age. Shortened telomeres in pancreatic tissue play a key role in the pathogenesis of pancreatic cancer, and shorter telomeres in peripheral blood leukocytes (PBL) have been associated with increased risk for several cancer types. We hypothesized that shorter blood telomeres are associated with higher risk for pancreatic cancer.
Telomere length was measured in PBLs using quantitative real-time PCR in 499 cases with pancreatic cancer and 963 cancer-free controls from the Mayo Clinic. ORs and confidence intervals (CI) were computed using logistic generalized additive models (GAM) adjusting for multiple variables.
In multivariable adjusted models, we observed a significant nonlinear association between telomere length in peripheral blood samples and the risk for pancreatic cancer. Risk was lower among those with longer telomeres compared with shorter telomeres across a range from the 1st percentile to 90th percentile of telomere length. There was also some evidence for higher risk among those with telomeres in the longest extreme.
Short telomeres in peripheral blood are associated with an increased risk for pancreatic cancer across most of the distribution of length, but extremely long telomeres may also be associated with higher risk.
Although the temporality of this relationship is unknown, telomere length may be useful as either a marker of pancreatic cancer risk or of the presence of undetected pancreatic cancer. If telomere shortening precedes cancer incidence, interventions to preserve telomere length may be an effective strategy to prevent pancreatic cancer.
端粒是染色体的末端,对于维持基因组的稳定性至关重要,其长度会随着年龄的增长而缩短。胰腺组织中端粒缩短在胰腺癌的发病机制中起着关键作用,外周血白细胞(PBL)中端粒缩短与多种癌症类型的风险增加有关。我们假设血液端粒较短与胰腺癌风险增加有关。
在梅奥诊所的 499 例胰腺癌病例和 963 例无癌症对照中,使用实时定量 PCR 测量 PBL 中的端粒长度。使用逻辑广义加性模型(GAM)调整多个变量后,计算比值比(OR)和置信区间(CI)。
在多变量调整模型中,我们观察到外周血样本中端粒长度与胰腺癌风险之间存在显著的非线性关联。与较短的端粒相比,端粒较长的患者风险较低,跨越端粒长度的第 1 百分位数到第 90 百分位数的范围。在端粒最长的极端范围内,也有一些更高风险的证据。
外周血中的短端粒与胰腺癌风险的增加有关,跨越了长度分布的大部分范围,但极长的端粒也可能与更高的风险相关。
尽管这种关系的时间顺序尚不清楚,但端粒长度可能既可以作为胰腺癌风险的标志物,也可以作为未检测到的胰腺癌的标志物。如果端粒缩短先于癌症发生,那么保护端粒长度的干预措施可能是预防胰腺癌的有效策略。