PTEN and prostate intraepithelial neoplasia: In vivo studies using Nkx3.1; Pten mice revealed that Jun and Fos mRNA levels are low in normal prostate and low-grade prostatic intraepithelial neoplasia (PIN), but increase significantly in androgen-dependent high-grade PIN/cancer (2.8-fold and 3.9-fold, respectively) and further rise in advanced androgen-independent lesions (4.8-fold and 8.3-fold; Ouyang et al., 2008).