Looking for tissue-specific alteration in proteasome units, researchers treated mice with 3H-1,2-dithiole-3-thione (D3T), which functions as a cancer preventive agent proved both in animal and human studies; 24 h later, expression of the 20S catalytic core subunits PSMB5, PSMB6 and PSMB7 were increased in liver, lung, small intestine and colon of mice (Kwak et al, 2007a). This evidence concerns the gene PSMB5 and cancer.