KDM1A and neoplasm: For instance, demethylation of p53 K370me2 by LSD1 inhibits the interaction of p53 with the cofactor p53-binding protein 1, thus repressing pro-apoptotic activity [28], whereas demethylation of HIF-1α at K391 protects HIF-1α against ubiquitin-mediated protein degradation, enhancing tumor angiogenesis [29].