MP45-10 BLEBBISTATIN MODULATES PROSTATIC CELL GROWTH AND CONTRACTILITY THROUGH MYOSIN II SIGNALING

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Basic Research & Pathophysiology1 Apr 2018MP45-10 BLEBBISTATIN MODULATES PROSTATIC CELL GROWTH AND CONTRACTILITY THROUGH MYOSIN II SIGNALING Ping Chen, Deqiang Xu, He Xiao, Xinghuan Wang, Michael E DiSanto, and Xinhua Zhang Ping ChenPing Chen More articles by this author , Deqiang XuDeqiang Xu More articles by this author , He XiaoHe Xiao More articles by this author , Xinghuan WangXinghuan Wang More articles by this author , Michael E DiSantoMichael E DiSanto More articles by this author , and Xinhua ZhangXinhua Zhang More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.1449AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Benign prostatic hyperplasia (BPH) is mainly caused by increased prostatic volume and smooth muscle (SM) tone. Non-muscle myosin II (NMM II) and SM myosin II (SMM II) play important roles in mediating cell growth and SM tone. Blebbistatin (BLEB, a small, cell permeable molecule which inhibits NMM II) has been recently suggested to inhibit SM contraction. The aim of this study is to investigate the effect of blebbistatin on regulating contractility and growth of prostate cells and to provide insight into possible mechanisms associated with these actions. METHODS BPH-1 (human epithelia cell line) and WPMY-1 (human stroma cell line) cells were utilized for in vitro studies. For in vivo studies, 2-weeks of BLEB treatment was administered by direct injection to the rat prostate. Cell growth was determined by flow cytometry analysis and in vitro organ bath studies were performed to explore contractility of rat prostate. SMM isoforms, including SM myosin heavy chain (MHC) isoforms (SM1/2 and SM-A/B) and myosin light chain 17 isoforms (LC17a/b), isoform ratios were determined via competitive RT-PCR. SM MHC, NM MHC isoforms (NMMHC-A and NMMHC-B) and proteins related to cell apoptosis and cell cycle were further analyzed via Western blotting and Masson's trichrome staining was used to determine epithelium, SM and collagen content. RESULTS In vitro experiments displayed that BLEB could dose-dependently trigger apoptosis and retard the growth of BPH-1 and WPMY-1. Consistent with this in vitro effect, administration of BLEB to the prostate could decrease rat prostatic epithelia and SM cells via increased apoptosis. Western blotting confirmed the effects of BLEB on inducing apoptosis through a mechanism involving MLC20 dephosphorylation with downregulation of Bcl-2 and upregulation of BAX and cleaved caspase 3. Meanwhile, NMMHC-A and NMMHC-B, the downstream proteins of MLC20, were found significantly attenuated in BPH-1 and WPMY-1 cells, as well as rat prostate tissues. In addition, in vivo experiments also demonstrated that BLEB not only decreased SM cells and SM MHC expression, but also lessened phenylephrine (PE) induced contractile force and altered prostate SMM II isoform composition, with upregulation of SM-B and downregulation of LC17a, favoring a faster contraction. CONCLUSIONS Our novel data demonstrated that BLEB regulates myosin II expression and functional activity in vivo and in vitro. Thus, our study indicated that BLEB not only decreased prostate size (static component) but also changed the prostatic SM tone (dynamic component). © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e601 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Ping Chen More articles by this author Deqiang Xu More articles by this author He Xiao More articles by this author Xinghuan Wang More articles by this author Michael E DiSanto More articles by this author Xinhua Zhang More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...