Finally, the combined inhibition of the proteasome (with marizomib, 0.15–0.7 mg/m2 i.v. on days 1, 8 and 15 of 28 day cycles) and of HDAC (with vorinostat, 300 mg orally every day on days 1–16 of each cycle) in patients with solid tumors (with the exclusion of patients with brain metastases and prior treatment with other HDAC- or proteasome-inhibitors) has been shown in a phase I trial to be well tolerated, with indications of anti-melanoma activity [SD in 11/14 (79%) melanoma patients, of which 4 maintained SD for at least 4 months] (161). This evidence concerns the gene HDAC9 and melanoma.