Identification of a gene on human chromosome 8q11 that is differentially expressed during prostate-cancer progression

Using differential-display RT-PCR analysis between androgen-dependent LNCaP -FGC and androgen-independent LNCaP-LNO human prostate-cancer cells, we hav e identified a gene not previously described as being expressed in prostate . The gene is more highly expressed in androgen-independent than in androge n-dependent LNCaP prostate-cancer cells. Sequence analysis showed that the gene has already been cloned as a transcript present in embryonic brain, wi th unknown functions. Expression of the gene was found not to be restricted to the prostate, and not regulated by androgens in androgen-independent pr ostate-cancer cells. In concert with the cell-culture system, Northern-blot analysis of gene expression in vivo, using a panel of human prostate-cance r xenografts, demonstrated that the gene is more highly expressed in androg en-independent than in androgen-dependent prostate-cancer xenografts, The g ene could be mapped on human chromosome 8q11. The 8q arm is known to be fre quently amplified during prostate-cancer progression and harbors several pr oto-oncogenes potentially involved in cancer development. Since expression of the gene is positively correlated with prostate-cancer progression and i ts 8q I I chromosomal localization, we hypothesize that the gene may be inv olved in the development and progression of prostate cancer. Int. J, Cancer 83:506-511, 1999, (C) 1999 Wiley-Liss, Inc.