Available for licensing from the Laboratory of Cancer Biology and Genetics of the National Cancer Institute (NCI) is a novel gene signature of thirty-seven drug-responsive genes that links changes in gene expression to the clinically desirable outcome of improved overall survival. Expression of these genes has been linked to prognosis in several cancers, including, but not limited to: multiple myeloma, melanoma, and lung and breast cancers. Patients identified by this signature would be predicted to benefit from combined HDAC inhibitor/mTOR inhibitor therapy.