Given that PTEN loss of heterozygosity has been frequently observed in human tumors, Lzts2LoxP/LoxP-PtenloxP/Wt:PB-Cre4 mice may mimic what occurs during the course of human prostate cancer development, and can be used to characterize this mechanism of prostate cancer initiation and progression. Here, PTEN is linked to prostate carcinoma.