Aberrant Promoter Methylation of Multiple Genes during Pathogenesis of Bladder Cancer

Purpose: The aims of our study were to elucidate the role of methylation of a large panel of genes during multistage pathogenesis of bladder cancer and to correlate our find-ings with patient age and other clinicopathologic features. Experimental Design: We studied the methylation status of 21 genes by quantitative methylation-specific PCR in an evaluation set of 25 tumor and 5 normal samples. Based on methylation frequency in tumors and normals in gene evaluation set, we selected 7 candidate genes and tested an independent set of 93 tumors and 26 normals. The presence or absence of methylation was evaluated for an association with cancer using cross-tabulations and C2 or Fisher’s exact tests as appropriate. All statistical tests were two-sided. Results: Most primary tumors (89 of 93, 96%) had meth-ylation of one or more genes of independent set