Expression of different genes in transitional zone and peripheral zone of human normal prostate

Abstract

To detect the expression of different genes in the transitional zone and peripheral zone of human normal prostate. Seventeen specimens of normal prostate gland were obtained from dead kidney donors and patients undergoing total cystectomy. The transitional zone and peripheral zone were isolated. Twenty specimens of benign prostate hypertrophy (BPH) were obtained from patients undergoing prostatic enucleation. The periurethral significantly hypertrophic nodules were isolated. BioDoor Chip-40S containing 6700 clones of targeting gene cDNA was used to detect the gene expression. The peripheral zone RNA samples were labeled with cy3, and the transitional zone RNA samples labeled with Cy5. The genes with the ratio average (RA) < 0.5 or > 2 were identified as differentially expressed genes, and those with a RA < 0.2 or > 4 were identified as the most significantly differentially expressed genes. RT-PCR was used to investigate semi-quantitatively the expression of epidermal growth factor (EGF) mRNA in the 17 specimens of transitional zone and peripheral zone from the 17 normal prostate glands and the 20 specimens of periurethral zone from BPH. A total of 640 genes differentially expressed in transitional zone and peripheral zone were screened out (comprising 269 unknown genes and 371 known genes), of which 294 genes were expressed in the transitional zone and 346 in the peripheral zone. Fourteen genes were identified as markedly differentially expressed, among which the EGF gene was highly expressed in the central zone, and the OSF-1 (osteoblast stimulating factor-1) gene was highly expressed in the peripheral zone. RT-PCR proved that in comparison with the expression of the internal marker beta-actin gene, the expression levels of EGF in the normal transitional zone and in the periurethral zone from BPH were markedly higher than that in the peripheral zone. There are differently expressed genes between the peripheral zone and central zone of normal human prostate, which may be the background of different biological behavior between these zones. EGF may markedly contribute to the growth of central zone of normal prostate.