Moreover, treatment of prostate cancer cells with tubacin, an HDAC6 inhibitor, in a dose-dependent manner completely inhibited TGF-β-induced expression of c-Jun mRNA, as well as migration and invasion (Figures 8, S1C, S1D, S1G, and S1H), giving further experimental evidence for the important role for HDAC6 in TGF-β-induced migration and invasiveness of cancer cells and support for the potential usefulness of HDAC6 inhibitors for patients with aggressive prostate cancer. This evidence concerns the gene JUN and cancer.