On the one hand, studies have shown chemical compounds that are able to inhibit K685 acetylation (e.g., resveratrol [76] and garcinol [80]), which is correlated with STAT3-dependent methylation of tumor suppressor genes; on the other hand, studies have tried to find HDAC inhibitors (e.g., panobinostat [77] and SAHA [78]) for the treatment of malignant lymphoma (in which HDAC inhibition promotes cell death) [77] or to regulate the immune response (by modulating IDO induction in dendritic cells) [78]. This evidence concerns the gene HDAC9 and lymphoma.