In contrast to the expression pattern, we found that the methylation level of CST6 was significantly lower in BLCA, CESC, COAD, ESCA, HNSC, KIRP, LUAD, PAAD, READ, THCA, and UCEC tumor samples, while it was higher in BRCA, KIRC, liver hepatocellular carcinoma (LIHC), and prostate adenocarcinoma (PRAD) (Wilcoxon test, p-value < 0.05, Figure 3A). Here, CST6 is linked to prostate adenocarcinoma.