Objectives: To assess the medical applicability of CpG methylation as molecular markers for cancer diagnosis, we established a new system to determine DNA methylation based on TaqMan PCR combined with a methyl-binding-domain polypeptide 2.
Design and methods: We evaluated the diagnostic applicability of this approach by examining the methylation status of two tumor suppressor genes, RASSF1A and APC, in 10 paired hepatocellular carcinoma (HCC) and the corresponding non-tumor liver tissues.
Results: Methylation levels of total 20 clinical samples measured by the TaqMan PCR assay showed a significantly positive correlation (R=0.814, P<0.0005 for RASSF1A, R=0.736, P<0.00001 for APC) with those calculated by bisulfite sequencing. The methylated DNA amount measured by our TaqMan PCR system precisely replicated the methylation status estimated by direct sequencing.
Conclusions: This suggests our method may serve as a reliable and easy-to-use tool for cancer diagnosis using methylated genes as biomarkers.