Differentially expressed genes in muscle from tumor bearing mice were similar to those previously published in severe C26 cancer cachexia [31] such as upregulation of acute phase response genes, ubiquitin-proteasomal degradation genes, autophagy genes, key atrophy genes including MuRF1, atrogin/MAFbx (Fbxo32), Fbxo30, Fbxo31, cathepsin L, caspase4, Foxo1, Foxo3, Stat3, Socs3, C/EBPδ, Bcl-3, myogenin, Jun B, etc.). The gene discussed is CTSL; the disease is cancer.