Furthermore, simultaneous inactivation of one Pten allele and one or more Cdkn1b (encoding p27Kip1) alleles accelerated neoplastic transformation and increased tumor incidence in a mouse prostate cancer model [102], implying that p27Kip1 plays a crucial role in mediating the tumor-suppressive effect of PTEN. This evidence concerns the gene PTEN and prostate carcinoma.