Ongoing studies focus on the identification of novel therapeutic approaches aiming at oncogenic molecular targets to improve therapy efficacy for stage 4 patients.26, 27 The use of HDAC inhibitors is emerging as an effective treatment strategy for cancer therapy.28, 29 Several HDAC inhibitors are being tested in phase I–III clinical trials and show significant responses in leukemias and lymphoma. Here, HDAC9 is linked to lymphoma.