Original Contribution
The American Journal of Gastroenterology (2005) 100, 2274–2279; doi:10.1111/j.1572-0241.2005.50412.x
Quantitative Detection of Promoter Hypermethylation in Multiple Genes in the Serum of Patients with Colorectal Cancer
Wai K Leung MD1, Ka-Fai To MD2, Ellen PS Man MD, PhD1, Michael WY Chan PhD1, Alfa HC Bai MPhil1, Aric J Hui MBChB, MRCP1, Francis KL Chan MD1 and Joseph JY Sung MD, PhD1
- 1Department of Medicine & Therapeutics,
- 2Department of Anatomical & Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
Correspondence: Wai K Leung, Department of Medicine & Therapeutics, Prince of Wales Hospital, 30-32 Ngan Shing Street, Shatin, Hong Kong
Received 16 March 2005; Revised 0000; Accepted 22 April 2005.
Abstract
OBJECTIVES:
While promoter hypermethylation is a common molecular alteration of human colorectal cancer that could be detected in the bloodstream, we tested the feasibility of quantitative detection of aberrant DNA methylation in multiple genes in the serum samples of colorectal cancer patients.
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.
