Probasin promoter-driven expression of ID1 is not sufficient for carcinogenesis in rodent prostate.

Inhibitor of DNA-binding-1 (ID1) negatively regulates cell differentiation and senescence, and enhances cellular proliferation and angiogenesis. Elevated levels of ID1 have been found in a variety of cancers, including prostate cancer, but whether ID1 has a tumourigenic role remains to be established. We established heterozygous and homozygous ID1-transgenic mouse lines driven by the prostate-specific probasin promoter (-426 to +28 bp). Although elevated levels of ID1 were confirmed by RT-PCR, immunohistochemistry, and Western blot analysis, there were no morphological changes identified in the prostate of transgenic mice at 26 and 52 weeks. Thus, overexpression of ID1 alone is not sufficient to drive neoplastic change in mouse prostate.