The concordance between CDH1 and APC methylation in IDCs and paired circulating DNA underscores the utility of serum DNA as a non-invasive tool for methylation analysis in IDC patients.
Moreover, to assess whether mutations of genes interacting with APC can substitute or act in association with APC alterations, we sequenced both CTNNB1 (beta-catenin) and CDH1 (E-cadherin) genes.No CTNNB1 or CDH1 mutations were found.
This suggests that the normal APC and E-cadherin protein expressions in benign epithelium are progressively and independently lost in the sporadic colorectal cancers.