PTEN and neoplasm: To determine whether overexpressed GP73 contributes to accelerated tumor development in HBV; Pten−/− mice, global GP73 knockout (Gp73−/−) mice were crossed with HBV; Pten−/− mice to generate HBV; Pten−/− and HBV; Pten−/−; Gp73−/− mice.