Rapid and reliable detection of LINE-1 hypomethylation using high-resolution melting analysis

Objectives: The aim of the present study was to evaluate the precision and reproducibility of the LINE-1 high-resolution melting (HRM) assay to detect LINE-1 hypomethylation. Design and methods: We first evaluated a methylated DNA dilution matrix and a panel of human cancer cell lines. We then applied this LINE-1 HRM assay to a set of 37 archival prostate cancer tissue samples. Results: Our LINE-1 HRM assay revealed small and reproducible run-to-run and bisulfite-to-bisulfite variations. As expected, we found a large variation in methylation levels between different cancer cell lines. All results were confirmed with MethyLight and pyrosequencing as indicated by the high correlation coefficient. Finally, we successfully applied the LINE-1 HRM assay to archival prostate cancer tissues. Conclusions: The present LINE-1 HRM assay represents a novel, accurate, and cost-effective method to measure global hypomethylation, which makes it suitable for high- and low-throughput laboratories. (C) 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.