APP and cancer: Interestingly, methylation levels of ALK and BCL2 were positively correlated with mRNA expression levels of ALK and BCL2 in most cancer types, as well as the positive correlation between methylation level of APP and mRNA expression level of APP in liver hepatocellular carcinoma (LIHC) and the positive correlation between methylation level of CD40 and mRNA expression level of CD40 in esophageal carcinoma (ESCA) (Fig. S2E).