At the same time, the expression level of ALKBH5 was significantly increased in SKOV‐3 and Ishikawa co‐cultured cells (Figure 5B); meanwhile, all the expression levels of NANOG, SOX‐2 and OCT‐4 increased in ovarian cancer tissues (Figure 5C), but fell in ovarian cancer cell lines (Figure 5D). Here, NANOG is linked to ovarian carcinoma.