The methylation level of the CLK1 locus was predicted to be negatively correlated with overall survival of the ESCC patients (Figure 2G) and disease-free survival of ESCC patients in the TCGA-ESCA cohort (Figure 2H), even after adjusting for multiple clinical factors, including gender and TNM staging (Figure 2I). Here, CLK1 is linked to esophageal squamous cell carcinoma.