Table of Contents
Molecular Biology International
Volume 2012, Article ID 701814, 8 pages
http://dx.doi.org/10.1155/2012/701814
Research Article

Combined RASSF1A and RASSF2A Promoter Methylation Analysis as Diagnostic Biomarker for Bladder Cancer

1Department of Radiation Oncology, The Ohio State University, Columbus, OH 43210, USA
2Department of Urology, The Ohio State University, Columbus, OH 43210, USA

Received 1 November 2011; Accepted 29 December 2011

Academic Editor: Farida Latif

Copyright © 2012 Wei Meng et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Promoter hypermethylation, a widely studied epigenetic event known to influence gene expression levels, has been proposed as a potential biomarker in multiple types of cancer. Clinical diagnostic biomarkers are needed for reliable prediction of bladder cancer recurrence. In this paper, DNA promoter methylation of five C-terminal Ras-association family members (RASSF1A, RASSF2A, RASSF4, RASSF5, and RASSF6) was studied in 64 formalin-fixed paraffin-embedded (FFPE) bladder cancer and normal adjacent tissues using methylation-specific high-resolution melting (MS-HRM) analysis. Results showed that 73% (30/41) of transitional cell carcinoma, 100% (3/3) of squamous cell carcinoma, and 100% (4/4) of small cell carcinoma demonstrated promoter methylation of the RASSF1A or RASSF2A gene, but only 6% (1/16) of normal tissues had promoter methylation of RASSF genes. Testing positive for hypermethylation of RASSF1A or RASSF2A promoter provided 77% sensitivity and 94% specificity for identification of cancer tissues with an area under the curve of 0.854, suggesting that promoter methylation analysis of RASSF1A and RASSF2A genes has potential for use as a recurrence biomarker for bladder cancer patients.