Effect of prostate peripheral zones stromal cells on the proliferation of prostate cells by overexpression of LMO2 gene

To explore the biological effect of prostate peripheral zones (PZs) stromal cells on the proliferation of prostate cells by overexpression of LMO2 gene.Genes expressional distinction of different prostate stromal cells was screened by gene expression arrays. To validate the microarray data, real time-polymerase chain reaction (RT-PCR), Western blotting analysis were used to check the over expression of LMO2 in PZs cells.To compare the effect of stromal cells which overexpressed LMO2 gene on in vitro proliferation ability of BPH-1 and PC3 cell lines, cell proliferation was measured by CCK-8 and EdU assay. Cytokines chip was used to screen expression of cytokines in WPMY-1-LMO2 conditioned medium. The changes of BPH-1 and PC3 proliferation associated proteins were assessed by Western blotting.A total of 512 genes were identified as markedly differentially expressed in stromal cells originated from different zones. Among these genes, LMO2 gene was overexpression in peripheral zones stromal cells, and confirmed by RT-PCR and Western blotting. Expression level of LMO2 gene was significantly up-regulated in peripheral zones stromal cells compared with transitional zones stromal cells, increased by 3.36 folds on average (P<0.01). The proliferation of both PC3 and BPH-1 were found increased and STAT3 phosphorylation and CCND1 expression were increased after cultured in conditioned medium from stromal cells which stably expressed LMO2. Cytokines chip found increased FGF-9 and IL-11 expression in the medium supernatant reserved from LMO2-overexpressed stromal cell line.Distinct gene expression exists among prostate stromal cells originated from different zones. LMO2 overexpressed stromal cells can induce prostate epithelial cell growth via paracrine of FGF-9, IL-11 or other cytokines.