HDAC9 and mantle cell lymphoma: MCL patients considered ineligible for ASCT (elderlies and/or “unfit”) may receive a variety of non-enhanced immunochemotherapy regimens (not based on HDAC), such as R-CHOP [rituximab, cyclophosphamide, doxorubicin, and prednisone], BR [bendamustine, rituximab], VR-CAP [bortezomib, rituximab, cyclophosphamide, adriamycin, and prednisone], or R2 [rituximab plus lenalidomide], followed by maintenance with rituximab [3,4,13,14].