S100A4 and prostate intraepithelial neoplasia: We previously reported spontaneous development of forestomach squamous cell carcinoma and prostatic intraepithelial neoplasia in mice with fibroblastic conditional knockout of the Tgfbr2 gene.5 These mice, termed Tgfbr2fspKO, were developed by crossing Tgfbr2floxE2/floxE2 mice to transgenic mice expressing Cre recombinase driven by the FSP-1 (fibroblast specific protein-1 or S100A4) promoter.