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.
OBJECTIVES: While promoter hypermethylation is a common molecular alteration of humancolorectal 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 cancerpatients. METHODS: The pre-therapeutic serum samples of 49 colorectal cancerpatients and 41 age-matched controls with normal colonoscopy were examined. The presence of methylated DNA in APC (adenomatous polyposis coli), hMLH1 (humanMutL 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 cancerpatients 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.
Authors: Shawn A Ritchie; Pearson W K Ahiahonu; Dushmanthi Jayasinghe; Doug Heath; Jun Liu; Yingshen Lu; Wei Jin; Amir Kavianpour; Yasuyo Yamazaki; Amin M Khan; Mohammad Hossain; Khine Khine Su-Myat; Paul L Wood; Kevin Krenitsky; Ichiro Takemasa; Masakazu Miyake; Mitsugu Sekimoto; Morito Monden; Hisahiro Matsubara; Fumio Nomura; Dayan B Goodenowe Journal: BMC Med Date: 2010-02-15 Impact factor: 8.775