MGMT and chronic hepatitis: Major and Collier (1998) suggested that MGMT protein activity decreased in chronic hepatitis, cirrhosis, and HCCs. We have recently reported that the MGMT expression was frequently lost in a variety of human tumours and was a significant prognostic factor (Matsukura et al, 2001). Since loss of MGMT expression was not commonly because of a genetic change, it has been suggested that another cause, such as epigenetic change, is involved (Esteller et al, 1999; Bhakat and Mitra, 2000).