OBJECTIVETo investigate the effects of estrogen receptor alpha (ERa) and insulin-like growth factor 1 (IGF1) on the proliferation of prostatic smooth muscle cells (PSMCs) in vitro.

METHODSThe ERalpha shRNA expression frame was subcloned to the pGSadeno adenovirus vector by homologous recombination technology to construct the pGSaaeno-ERalpha vector. After the mouse PSMCs were transfected in vitro by pGSaaeno-ERalpha, the mRNA and protein expression levels of ERalpha were detected by RT-PCR and Western blot respectively. The expression of IGF1 in the ERa-reduced cells was determined by Western blot 6 hours after treatment with 17beta-estradiol (E2) at 10(-8) mol/L. The post-transfection activity of estrogen or exogenous IGF1 in the proliferation of PSMCs was evaluated by MTT chlormetric analysis.

RESULTSAfter treatment with E2, the proliferation of PSMCs and the expression of the IGF1 gene were significantly increased in the normal control group (P <0.05), but not obviously changed in the ERalpha-siRNA group (P> 0.05). And exogenous IGF1 failed to induce the proliferation of the ERalpha-reduced PSMCs.

CONCLUSIONE2 induces the expression of IGF1 via ERalpha, and IGFl, with the interaction of ERalpha, promotes the proliferation of PSMCs.