Epigenetic inactivation of HOXA5 and MSH2 gene in clear cell renal cell carcinoma.

The high-throughput method using microarray is an easy and fast way to analyze the methylation status of hundreds of preselected genes and to screen them for signatures in methylation. The aim of our study is to detect hypermethylated genes and to analyze the association between methylation status and clinicopathological parameters of clear cell renal cell carcinoma. The genetic substrate included 62 cancer tissues and 62 matched adjacent normal kidney tissues. We adapted the GoldenGate genotyping assay to determine the methylation state of 1505 specific CpG sites in 807 genes. We identified two genes (HOXA5 and MSH2) with β-value differences of more than 0.3 between cancer and normal tissues. The high methylation group in HOXA5 had high Fuhrman's nuclear grade (P= 0.041). Other data in HOXA5 and MSH2 were not significant with methylation status (P > 0.05). Survival curve of the high methylation group in HOXA5 was slightly lower than that of the low methylation group. However, the statistical significances of overall survival in HOXA5 and MSH2 were low (P > 0.05). We report the hypermethylation of two genes in clear cell renal cell carcinoma. The data we obtained could provide the basis for a diagnostic test pathological assessment, or prognosis in clear cell renal cell carcinoma.