Differential gene expressions in the stromal cells of the human prostate peripheral zone in males of different ages

Objective: To study the gene expressions in the stromal cells of the human prostate peripheral zone(PZ) in men of different ages.Methods: We primarily cultured stromal cells from the normal prostate PZ of men aged 23-32(young group) and 56-75 years(old group),profiled the gene signature of the PZ cells by cDNA microarray,and defined the differential gene expression patterns by hierarchical cluster analysis.Among the differential genes,we selected and confirmed up-regulated genes by quantitative real time PCR(Q-PCR),and identified their protein coding by Western blotting.Results: There were significant differences in the gene expressions of the PZ cells between the old and young groups.Based on the fold change ratio of ≥ 2 or ≤ 0.5,509 up-regulated and 188 down-regulated genes were selected in the PZ cells.A subset of significantly differential genes influencing the growth of adjacent epithelial cells were identified,including HGF,IGF2,IGFBP5 and MMP1 in the old males.Conclusion: Stromal cells in the prostate PZ were more active in older males in promoting the malignant progression of adjacent prostate epithelial cells,which might be due to the increased expression of extracellular paracrining mediators.