Non-classical testosterone signaling implications in prostate smooth muscle cell proliferation and muscle cell phenotype

CUELLO RUBIO, M; QUINTAR, A; LEIMGRUBER, C; NICOLA, JP; PEINETTI, N; SCALERANDI, MV; MALDONADO, C

Mar del Plata

Congreso; LXI Reunión científica anual de la Sociedad Argentina de Investigación Clínica; 2016

Sociedad Argentina de Investigación Clínica

Testosterone (T) effects are mediated by a classical pathwaythat takes place through the binding of T to the classical androgenreceptor (AR) and migration to the nucleus, and by non-classicalsignaling pathways which are mediated by cell surface receptorscapable of activating signaling cascades. The differentiation andproliferation of pSMC as cell as the stroma/epithelium interactionare essential in the development of prostatic pathologies. ourobjectives were to determine the presence of plasma membraneAR receptors in pSMC and their participation in cell differentiation,proliferation and growth factors expression. pSMC were obtainedfrom Wistar rat prostate and stimulated in vitro with T 10-7 M orthe plasma membrane impermeable T-bovine serum albuminconjugate (T-BSA) 10-7M. Smooth muscle markers and the expressionof FGF7 and TGF-b were evaluated by qPCR, and cellproliferation was assessed by immunocytochemistry of Ki67, andconfirmed by cell counter; statistical analysis was performed byANOVA-Tukey. The AR plasma membrane localization was demonstratedby immunofluorescence and confocal microscopy, andby co-localization with the membrane marker concanavalin-A. Thisassay was verified by flow cytometry, which showed a populationof membrane AR positive cells of 18.87%. After T-BSAstimuli, an increased expression of smooth markers calponin andα-actin was observed 􀀊p􀀞􀀒.􀀒􀀓 vs ctrl􀀋, while vimentin 􀀴􀀰Am 􀁙asdecreased 􀀊p􀀞􀀒.􀀒􀀓 vs ctrl􀀋. T-BSA also increased cell proliferationafter 􀀔􀀖 or 􀀖􀀚 hours stimulation 􀀊p􀀞􀀒.􀀒􀀗 vs ctrl and T􀀋. Meanwhile,T increased FGF7 and TGF-b, implicated in proliferation and apoptosisof epithelial cells respectively, at higher levels than T-BSA􀀊p􀀞􀀒.􀀒􀀓􀀋. These results demonstrated the presence of membranereceptors and the participation of non-classical signaling mediatingT-induced pSMC proliferation and differentiation; genomic effectswere stronger modulators of growth factors implicated prostatecell communication.