Epigenetic inactivation of protocadherin 10 by methylation in colorectal cancer

Aberrant promoter methylation of CpG islands of tumor-suppressor genes has been recognized as one of the important tumor markers for cancer detection. The aim of this study was to investigate the promoter methylation status of protocadherin 10 (PCDH10), a tumor suppressor gene, in Iranian CRC patients. Cancerous and the adjacent normal tissues obtained from 38 CRC patients were used to assess methylation status of PCDH10 with Methylation Specific PCR in addition to study the expression level of this gene by quantitative PCR. The relationship between hypermethylation and demographic characteristics of these patients was analyzed. Promoter methylation level of PCDH10 was statistically different between tumoral and normal tissues in CRC patients. Twenty seven out of 38 patients showed hypermethylation with a sensitivity of 73% and a specificity of 97%. PCDH10 expression decreased in 15 cases (46%) as 16 cases (50 %) showed over- expression and 1 case (4%) had no changes. Not a significant association was reported between PCDH10 hypermethylation and the clinicopathological characteristics (p value>0.05). Our results indicated that PCDH10 methylation has critical function in CRC, with a nearly elevated sensitivity and a high specificity in Iranian population, qualify it as a potential candidatebiomarker.