KDM5B and cancer: Since KDM5B probably acts as a transcriptional regulator by its ability to remove tri-, di-, and monomethyl groups from H3K4, several cancer-associated genes regulated by KDM5B have been identified, including tumor suppressor gene BRCA1 that is repressed by KDM5B and transcription factors E2F1 and E2F2 that are up-regulated by KDM5B [19, 28, 29].