Our current results demonstrate that 5-aza-dC and another methylation inhibitor, zebularine, dose-dependently restored chemosensitivity to Round5 cells (Figure 2), and previously we reported upregulation of DNMT1 and DNMT3B in ovarian cancer cell lines, along with a potential positive correlation between DNMT1 overexpression and tumor aggressiveness [62]. Here, DNMT1 is linked to ovarian carcinoma.