and DNA methylation status and its utility in the diagnosis of colonic adenomas and colorectal adenocarcinomas.

Background: Colorectal cancer (CRC) appear to arise from precursor lesions in a well-characterized adenoma-carcinoma sequence. Significant efforts have been invested to develop biomarkers that identify early adenocarcinomas and adenomas with high-grade dysplasia, since these are believed to harbor a particularly high risk for malignant transition and thus require resection. Promoter methylation of and has been suggested as a biomarker for various solid malignant tumors. Hence, the present study aimed to test their biomarker potential in CRC and precursor lesions.

Results: Assessment of promoter methylation of distinguished adenomas and CRC from controls as well as advanced from non-advanced adenomas (all  < 0.001). Correspondingly, methylation levels in adenomas and colorectal carcinomas were significantly higher compared to those in normal control tissues ( < 0.001). Histologic transition from adenomas to CRC was paralleled by amplification of the gene locus.

Conclusions: / methylation assays may help to distinguish colorectal cancer and adenomas from normal and inflammatory colonic tissue, as well as advanced from non-advanced adenomas. Further studies need to validate these findings before introduction in clinical routine.