Tumor mass and proliferation within xenografts derived from immortalized human prostate cancer cells (e.g. PC3 or LNCaP) are generally increased in mice rendered obese by high-fat feeding compared with lean mice fed a low-fat diet [7–10], while diet-induced obesity accelerates prostate cancer progression /aggressiveness in transgenic mouse strains of prostate cancer (e.g. TRAMP, Hi-Myc, Pten−/+) [9–15]. Here, PTEN is linked to prostate cancer.