The aberrant function of LSD1 has been found to be able to stimulate many negative biological processes such as tumor initiation and progression, and is closely connected with various malignant tumors, especially lung cancer and leukemia (Wang et al., 2009; Magerl et al., 2010; Lokken and Zeleznik-Le, 2012). The gene discussed is KDM1A; the disease is leukemia.