To investigate the relationship between loss of function of Nkx3.1 and inflammation in the mouse prostate in vivo, we studied the germline Nkx3.1 mutant mouse model, which develops PIN as a consequence of aging and cooperates with loss of function of other tumor-suppressor genes in prostate tumorigenesis (Kim et al., 2002a,b; Bhatia-Gaur et al., 1999). Here, NKX3-1 is linked to prostate intraepithelial neoplasia.