Mechanistically, G9a-mediated deposition of H3K9me1/2 represses tumor-suppressor genes such as CDKN1A/p21, E-cadherin, and PTEN, thereby promoting cell proliferation, epithelial-to-mesenchymal transition (EMT), and chemoresistance (30, 50, 51, 52). This evidence concerns the gene CDKN1A and neoplasm.