Temple University School of Medicine, 3307 N. Broad Street, Room 154 PAHB, Philadelphia, PA 19140.
Cancer Prev Res (Phila). 2013 Oct;6(10):1093-100. doi: 10.1158/1940-6207.CAPR-13-0034. Epub 2013 Aug 13.
Whole blood DNA methylation analysis has been proposed to be a risk marker for cancer that can be used to target patients for preventive interventions. To test this, we examined whole blood DNA methylation of 16 CpG island promoters and LINE1 repetitive element in patients with gastric cancer and control subjects. Bisulfite pyrosequencing was used to quantify the methylation of 14 CpG island promoters (MINT25, RORA, GDNF, CDH1, RARAB2, ER, CDH13, MYOD1, SFRP1, P2RX7, SLC16A12, IGF2, DPYS, and N33) and LINE1 from 72 patients with gastric cancer, 67 control, and 52 healthy young individuals. Quantitative methylation-specific real-time PCR was also conducted for 3 CpG island promoters (MINT25, MYO3A, and SOX11). Among all sites tested, only a marginal increase in the methylation of the SFRP1 promoter was observed in the blood of patients with gastric cancer when compared with the control group (11.3 % vs 10.5%; age-adjusted P value: P = 0.009), and this association was also seen in a validation set of 91 patients with gastric cancer (11.5% vs 10.5%; age-adjusted P value: P = 0.001). The methylation of 9 sites (GDNF, CDH1, RARAB2, CDH13, MYOD1, SFRP1, SLC16A12, DPYS, N33, and LINE1) and their mean Z score was correlated with higher age (R = 0.41, P < 0.0001) and marginally with telomere shortening (R = -0.18, P = 0.01) but not with gastric cancer risk (other than SFRP1 methylation). Variability in whole blood DNA methylation of cancer markers is primarily associated with aging, reflecting turnover of white blood cells, and has no direct link to gastric cancer predisposition. SFRP1 methylation in whole blood may be associated with gastric cancer risk.
全血 DNA 甲基化分析已被提议作为癌症的风险标志物,可用于针对预防性干预措施的患者。为了检验这一点,我们检测了胃癌患者和对照者的全血 DNA 甲基化 16 个 CpG 岛启动子和 LINE1 重复元件。亚硫酸氢盐焦磷酸测序用于定量测定 14 个 CpG 岛启动子(MINT25、RORA、GDNF、CDH1、RARAB2、ER、CDH13、MYOD1、SFRP1、P2RX7、SLC16A12、IGF2、DPYS 和 N33)和 LINE1 的甲基化,来自 72 名胃癌患者、67 名对照者和 52 名健康年轻人。还进行了 3 个 CpG 岛启动子(MINT25、MYO3A 和 SOX11)的定量甲基化特异性实时 PCR。在所测试的所有位点中,与对照组相比,胃癌患者血液中 SFRP1 启动子的甲基化仅略有增加(11.3%对 10.5%;年龄调整后的 P 值:P=0.009),在另外 91 名胃癌患者的验证组中也观察到这种关联(11.5%对 10.5%;年龄调整后的 P 值:P=0.001)。9 个位点(GDNF、CDH1、RARAB2、CDH13、MYOD1、SFRP1、SLC16A12、DPYS、N33 和 LINE1)及其平均 Z 评分的甲基化与年龄较大(R=0.41,P<0.0001)和端粒缩短(R=-0.18,P=0.01)呈边际相关,但与胃癌风险(除 SFRP1 甲基化外)无关。癌症标志物全血 DNA 甲基化的变异性主要与衰老有关,反映了白细胞的更新,与胃癌易感性没有直接联系。全血 SFRP1 甲基化可能与胃癌风险有关。