Hypermethylation status of APC predicts the presence of submucosal invasion in laterally spreading colorectal tumors. Free

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Little is known about epigenetic alterations in laterally spreading colorectal tumors (LSTs). The goal of the present study was to elucidate the epigenetic background of LSTs and compare the methylation status of DNA CpG islands with clinicopathologic features.Methylation of MINT1, MINT2, MINT31, p16, MGMT, APC, and hMLH1 in 19 LSTs was assessed by methylation-specific PCR (MSP) and compared with clinicopathologic parameters. The frequency of hypermethylation was 13.3% (2/15) for MINT1, 36.8% (7/19) for MINT2, 36.8% (7/19) for MINT31, 26.7% (4/15) for p16, 11.8% (2/17) for hMLH1, 29.4% (5/17) for MGMT, and 44.4% (8/18) for APC. The status of methylation of APC was inversely associated with the presence of submucosal invasion. Submucosal invasion was found in 0 of 8 (0.0%) cases with APC methylation, in contrast with 5 of 10 (50.0%, P = 0.04) cases without APC methylation. We observed an inverse association between methylation of APC and submucosal invasion in LSTs, which suggests that these may be predictive markers for submucosal invasion in LSTs. Further studies with more samples are needed.