Inhibition of prostate smooth muscle contraction and prostate stromal cell growth by the WNK inhibitor WNK463 and WNK silencing

Liu, Yuhan (2022): Inhibition of prostate smooth muscle contraction and prostate stromal cell growth by the WNK inhibitor WNK463 and WNK silencing. Dissertation, LMU München: Medizinische Fakultät

Abstract

Background: α1-Blockers still represent the gold standard for treating lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). However, the limited effectiveness of α1-blockers may be associated with non-adrenergic contractions of prostate smooth muscle. In addition to smooth muscle contraction, prostate growth may contribute to LUTS suggestive of BPH as well, and combination therapies are still required to address both at once. Consequently, novel medications with improved efficacy are required. Recent studies suggested procontractile roles of WNK kinases, outside the prostate. Here, the effects of the WNK inhibitor WNK463 and WNK1-4 silencing were examined on human prostate tissues and human prostate stromal cells. Methods: The effects of WNK463 on smooth muscle contractions were examined in an organ bath, and the effects of WNK463 and WNK1-4 knockdown on viability, proliferation, apoptosis, cell contraction and action organization of WPMY-1 cells were examined by CCK-8, RT-PCR, EdU, flow cytometry, cell contraction assay and phalloidin staining, respectively, in cell culture. Results: WNK463 inhibited neurogenic contractions of human prostate tissues, using concentrations of 0.5 µM and 10 µM. Smooth muscle contractions induced by the α1-adrenergic agonists noradrenaline, phenylephrine, and methoxamine were reduced by 10 µM WNK463, while 0.5 µM WNK463 showed a no or only small inhibitions of contractions. Contractions by the thromboxane A2 analog U46619 and endothelin-1 were also reduced as well by 0.5 µM and by 10 µM WNK463. WNK463 reduced the viability of stromal cells at concentrations of 5 µM and 10 µM, but not at a concentration of 1 µM. Proliferation (in EdU assays and reflected by Ki-67 mRNA) was suppressed by 10 µM WNK463. Apoptosis was induced by 1 µM and 10 µM WNK463. Cell contraction was inhibited by 10 µM WNK463, as well as action organization. In addition, WNK expression was silenced by siRNAs for WNK isoforms 1-4, which showed similar inhibitory ef-fects on viability, proliferation, apoptosis, cell contraction and actin organization. Conclusions: WNK463 inhibited non-adrenergic and adrenergic, as well as neurogenic contractions in human prostate tissues. Substantial inhibitions were observed on viability, proliferation, reduction of apoptosis, cell contraction and actin organization in human prostate stromal cells by WNK463 and silencing of WNK isoforms 1-4. All effects of WNK463 on stromal cells were mimicked by silencing of WNK expression. WNKs might be a promising target for medical improvement of LUTS.

• Dokumententyp: Dissertationen (Dissertation, LMU München)
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften ; 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• Fakultäten: Medizinische Fakultät
• Sprache der Hochschulschrift: Englisch
• Datum der mündlichen Prüfung: 7. September 2022
• 1. Bericht­erstatter:in: Hennenberg, Martin