These different effects are related mainly to the abnormal physiological statuses of cancer cells, such as their abnormal gene expression (including that of insulin-like growth factor-1, DNA methyltransferase 1, and histone deacetylases) [68], enzyme activity [69], and activation of signaling pathways including the AKT, MAPK, and nuclear factor kappa B pathways [70]. Here, DNMT1 is linked to cancer.