Figure 4

Kaplan-Meier plots were constructed with methylation level cut-off values of 10.5 for DKK1 and 16.7 for SFPR4 respectively and log-rank tests were also performed using these cut-offs. There was a significant difference in the survival pattern of those patients above and below the methylation level cut-off for DKK1 but not for SFPR4 (unadjusted log-rank p = 0.046 and 0.404 respectively) as shown in A and B. With the MSI- and CIMP-positive carcinomas are excluded from this analysis, it remains the case that the hypermethylation of DKK1 and SFRP4 was significantly associated with poor survival for DKK1 and improved survival for SFRP4 as shown in C and D. The cut-off values for SFRP4 = 16.7 and DKK1 = 10.5 were defined as the average adenocarcinoma group methylation level for these genes.