HDAC9 and malignant colon neoplasm: Butyrate treatment of both HCT116 and HT29 human colon cancer cells reduced the levels of primary miR-17-92a (pri-miR-17-92a), precursor, and mature miR-92a; these effects were shared by other HDAC inhibitors (suberoylanilide hydroxamic acid (SAHA) and valproic acid).