Quantitative Detection of Promoter Hypermethylation in Multiple Genes in the Serum of Patients with Colorectal Cancer
METHODS: The pre-therapeutic serum samples of 49 colorectal cancer patients and 41 age-matched controls with normal colonoscopy were examined. The presence of methylated DNA in APC (adenomatous polyposis coli), hMLH1 (human MutL homolog 1), and HLTF (helicase-like transcription factor) was detected by quantitative methylation-specific PCR (MethyLight).
RESULTS: There was a significant difference in the concentration of methylated serum DNA between cancer patients and controls for HLTF (p= 0.015) and hMLH1 (p= 0.0001) genes, but not for APC gene (p= 0.21). In total, 28 patients with colorectal cancer and 4 controls had methylated DNA detected in at least one marker, which gave a sensitivity of 57% and specificity of 90%. All patients with methylation in two methylation markers had advanced (stage III/IV) cancer (p= 0.006) and patients with methylation in at least one marker tended to have a lower probability of survival (p= 0.08).
CONCLUSION: The quantitative detection of aberrant DNA methylation in serum may be a promising high-throughput approach for the noninvasive screening and monitoring of colorectal cancer.
(Am J Gastroenterol 2005;100:1–6)
Document Type: Research Article
Affiliations: 1: Department of Medicine & Therapeutics 2: Department of Anatomical & Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
Publication date: October 1, 2005