Subsequently, the levels of expression of DNMT1 and DNMT3A in stages I and IV, primary carcinoma as well as metastatic carcinoma were assessed by IHC, TCGA databases and Kaplan–Meier survival curves; a significant difference was found in the expression of DNMT3A (Fig. 5H, I and Fig. S6B, F–H), while DNMT1 differences were not significant (Fig. S6C-E, I-K). Here, DNMT1 is linked to metastatic carcinoma.