Among the most important histone demethylases associated with the development of cancer are LSD-1/KDM1A, and members of the Jumonji family JARID1A-1C/KDM5A-5C, JHDM1B/KDM2B, JMJD2C/KDM4C, JMJD2A/KDM4A, JMJD3/KDM6B, and UTX/KDM6A (Table 1), which will be analyzed in detail in the following paragraphs. The gene discussed is KDM4C; the disease is cancer.