One of the most promising ways to diagnose cancer especially colorectal cancer (CRC) is to trace its epigenetic events. In this article, a discovery step for detection of methylated DNA markers (MDMs) was performed using SureSelectXT Methyl-Seq in CRC case and control groups in addition to several methylation profiling datasets (GSE48684, GSE53051, GSE77718, GSE101764, and GSE42752). In silico validation of MDMs in colorectal and other cancers was conducted by Lnc2met. MethyLight assay was run on 40 and 47 case and control formalin-fixed paraffin-embedded tissues, respectively and the performance of selected genes were classified by support vector machine (SVM). As a result, 180 regions were identified among all common genes. In addition to SEPT9 and SFRP2, the best three MDM regions were selected from SLC30A10, AKR1B1 and GALNT14. Based on all assays, the best performance was accomplished by SEPT9/ AKR1B1 with 98% sensitivity, 99% specificity, 125 positive likelihood ratio, 0.02 negative likelihood ratio and 5074 diagnostic odds ratio. Our results indicate that the AKR1B1/ SEPT9 methylation panel detects CRC with a higher performance than SEPT9 methylation, which is a commercial diagnostic test for CRC. However, the creation of a clinically valuable test derived from this study requires performance evaluation in liquid biopsies.

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