CDH13 and FLBN3 gene methylation are associated with poor prognosis in colorectal cancer

The aim of this study was to identify potential epigenetic prognostic biomarkers for colorectal cancer (CRC) in the Chinese population. The methylation status of five tumor suppressor genes (CDH13, DLEC1, FBLN3, hMHL1 and RUNX3) was determined using manual microdissection followed by methylation-specific PCR in 85 paired CRC specimens and adjacent normal tissue. The results showed that methylation frequencies in cancerous tissues were 31.8% for CDH13, 37.6% for DLEC1, 38.8% for FBLN3, 22.4% for hMHL1 and 27.1% for RUNX3, all of which were significantly higher than in corresponding normal tissue. Furthermore, CDH13 methylation was associated with poor differentiation (P = 0.019) and tended to be predominant in advanced stages (P = 0.084); FBLN3 methylation was associated with advanced stages (P = 0.027) and lymph node metastasis (P = 0.029). Accordingly, the methylation status of CDH13 (P = 0.022), FBLN3 (P = 0.008), CDH13 and/or FBLN3 (P = 0.001) predicted adverse overall survival in CRC, while hMHL1 methylation showed a protective role in survival (P = 0.046). Cox proportional hazard models further indicated that CDH13 and/or FBLN3 methylation, but not that of hMHL1, was an independent prognostic factor for CRC. In conclusion, we found CDH13 and FBLN3 gene methylation are potential biomarkers for poor prognosis in CRC.