Onvansertib, a polo-like kinase 1 inhibitor, inhibits prostate stromal cell growth and prostate smooth muscle contraction, which is additive to inhibition by α1-blockers

Effects of carvedilol on human prostate tissue contractility and stromal cell growth pointing to potential clinical implications

BACKGROUND

Apart from antagonizing ß-adrenoceptors, carvedilol antagonizes vascular α1-adrenoceptors and activates G protein-independent signaling. Even though it is a commonly used antihypertensive and α1-adrenoceptors are essential for the treatment of voiding symptoms in benign prostatic hyperplasia, its actions in the human prostate are still unknown. Here, we examined carvedilol effects on contractions of human prostate tissues, and on stromal cell growth.

METHODS

Contractions of prostate tissues from radical prostatectomy were induced by electric field stimulation (EFS) or α1-agonists. Growth-related functions were examined in cultured stromal cells.

RESULTS

Concentration-response curves for phenylephrine, methoxamine and noradrenaline were right shifted by carvedilol (0.1-10 µM), around half a magnitude with 100 nM, half to one magnitude with 1 µM, and two magnitudes with 10 µM. Right shifts were reflected by increased EC50 values for agonists, with unchanged Emax values. EFS-induced contractions were reduced by 21-54% with 0.01-1 µM carvedilol, and by 94% by 10 µM. Colony numbers of stromal cells were increased by 500 nM, but reduced by 1-10 µM carvedilol, while all concentrations reduced colony size. Decreases in viability were time-dependent with 0.1-0.3 µM, but complete with 10 µM. Proliferation was slightly increased by 0.1-0.5 µM, but reduced with 1-10 µM.

CONCLUSIONS

Carvedilol antagonizes α1-adrenoceptors in the human prostate, starting with concentrations in ranges of known plasma levels. In vitro, effect sizes resemble those of α1-blockers used for the treatment of voiding symptoms, which requires concentrations beyond plasma levels. Bidirectional and dynamic effects on the growth of stromal cells may be attributed to "biased agonism".

Leptin Mediates Prostate Stromal Cell Proliferation, Smooth Muscle Contraction, and Mitochondrial Function in Benign Prostate Hyperplasia

Introduction

Leptin is a metabolic peptide hormone produced by adipocytes, with proven roles in proliferation of prostate cancer cells and of prostate cells in animal models of benign prostatic hyperplasia (BPH). Thus, the role of leptin as a molecular link connecting BPH and lower urinary tract symptoms (LUTS) suggestive of BPH with metabolic symptoms appears feasible but is still unknown. In fact, a connection between metabolic syndrome and BPH is becoming increasingly evident from epidemiologic studies. Key factors of Lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH/LUTS) are increased prostate smooth muscle tone, and prostate enlargement. Here, we examined the effects of leptin on contraction of human prostate smooth muscle and on growth of stromal cells.

Methods

We performed microarray analysis to identify genes (fold change ≥ 1.5) associated with BPH/LUTS progression, such as those involved in proliferation, apoptosis, and mitochondrial metabolism, in rat prostate tissue (data from GSE129561). We then used electric field stimulation (EFS) to induce frequency-dependent, neurogenic contractions of human prostate strips, which were enhanced by leptin. We also examined the effect of leptin on human prostate stromal cells (WPMY-1) and found increased cell proliferation and viability upon exposure. To explore the underlying mechanism, we conducted mitochondrial stress assay using near-infrared (NIR) fluorescent dye and flow cytometry (FACS) analysis and observed reduced cellular apoptosis and preserved mitochondrial membrane potential (∆ψM) after leptin treatment.

Results

Microarray analysis reveals that leptin regulates prostate smooth muscle contraction and stromal cell proliferation, shedding new light on its involvement in BPH/LUTS pathogenesis and mitochondrial function. We found that leptin enhanced the proliferation rate of prostate stromal cells relative to the control group (0.67 ± 0.05 vs 0.54 ± 0.08, p-value= 0.024). Moreover, leptin (100 ng/mL) potentiated the frequency-dependent, neurogenic contractions of prostate strips elicited by EFS (p= 0.047 between leptin and control group). We also show that leptin treatment increased the mitochondrial membrane potential of prostate stromal cells and inhibited mitochondrial apoptosis.

Discussion

Our results indicate that leptin stimulates the contractility and proliferation of smooth muscle and stromal cells in the human prostate, implying a potential role for leptin in exacerbating BPH/LUTS in obese men. Leptin modulation may be a beneficial therapeutic strategy for patients with metabolic syndrome and BPH/LUTS. Further studies are warranted to elucidate the mechanisms and implications of the leptin system in BPH/LUTS.

Emerging Bioprinting for Wound Healing

Bioprinting has attracted much attention due to its suitability for fabricating biomedical devices. In particular, bioprinting has become one of the growing centers in the field of wound healing, with various types of bioprinted devices being developed, including 3D scaffolds, microneedle patches, and flexible electronics. Bioprinted devices can be designed with specific biostructures and biofunctions that closely match the shape of wound sites and accelerate the regeneration of skin through various approaches. Herein, a comprehensive review of the bioprinting of smart wound dressings is presented, emphasizing the crucial effect of bioprinting in determining biostructures and biofunctions. The review begins with an overview of bioprinting techniques and bioprinted devices, followed with an in-depth discussion of polymer-based inks, modification strategies, additive ingredients, properties, and applications. The strategies for the modification of bioprinted devices are divided into seven categories, including chemical synthesis of novel inks, physical blending, coaxial bioprinting, multimaterial bioprinting, physical absorption, chemical immobilization, and hybridization with living cells, and examples are presented. Thereafter, the frontiers of bioprinting and wound healing, including 4D bioprinting, artificial intelligence-assisted bioprinting, and in situ bioprinting, are discussed from a perspective of interdisciplinary sciences. Finally, the current challenges and future prospects in this field are highlighted.

Adrenoceptors in the Lower Urinary Tract

Adrenoceptors importantly contribute to the physiological regulation of lower urinary tract (LUT) function and have become a target of several clinically successful treatments for major LUT diseases. In the bladder dome, β-adrenoceptor subtypes are found in multiple cell types and mediate relaxation of detrusor smooth muscle, perhaps partly indirectly by acting on afferent nerves and cells of the mucosa. β₃-adrenoceptor agonists such as mirabegron and vibegron are used to treat overactive bladder syndrome. In the bladder trigone and urethra, α₁-adrenoceptors cause contraction and thereby physiologically contribute to bladder outlet resistance. α₁-adrenoceptors in the prostate also cause contraction and pathophysiologically elevate bladder outlet resistance leading to voiding dysfunction in benign prostatic hyperplasia. α₁-adrenoceptor antagonist such as tamsulosin is widely used as a first-line option to treat LUT symptoms in men, but it remains unclear to which extent and how smooth muscle relaxation contributes to symptom relief.

Inhibition of α1-Adrenergic, Non-Adrenergic and Neurogenic Human Prostate Smooth Muscle Contraction and of Stromal Cell Growth by the Isoflavones Genistein and Daidzein

Isoflavone-rich legumes, including soy, are used for food production, as dietary supplements and in traditional medicine. Soy consumption correlates negatively with benign prostatic hyperplasia (BPH) and voiding symptoms. However, isoflavone effects on the prostate are hardly known. Here, we examined the effects on human prostate smooth muscle contractions and stromal cell growth, which are driving factors of voiding symptoms in BPH. Smooth muscle contractions were induced in prostate tissues from radical prostatectomy. Growth-related functions were studied in cultured stromal cells (WPMY-1). Neurogenic, α1-adrenergic and non-adrenergic contractions were strongly inhibited with 50 µM and by around 50% with 10 µM genistein. Daidzein inhibited neurogenic contractions using 10 and 100 µM. Agonist-induced contractions were inhibited by 100 µM but not 10 µM daidzein. A combination of 6 µM genistein with 5 µM daidzein still inhibited neurogenic and agonist-induced contractions. Proliferation of WPMY-1 cells was inhibited by genistein (>50%) and daidzein (<50%). Genistein induced apoptosis and cell death (by seven-fold relative to controls), while daidzein induced cell death (6.4-fold) without apoptosis. Viability was reduced by genistein (maximum: 87%) and daidzein (62%). In conclusion, soy isoflavones exert sustained effects on prostate smooth muscle contractions and stromal cell growth, which may explain the inverse relationships between soy-rich nutrition, BPH and voiding symptoms.

Permixon®, hexane-extracted Serenoa repens, inhibits human prostate and bladder smooth muscle contraction and exerts growth-related functions in human prostate stromal cells

AIMS

Recently, the European Association of Urology recommended hexane-extracted fruit of Serenoa repens (HESr) in their guidelines on management of non-neurogenic male lower urinary tracts symptoms (LUTS). Despite previously lacking recommendations, Permixon® is the most investigated HESr in clinical trials, where it proved effective for male LUTS. In contrast, underlying mechanisms were rarely addressed and are only marginally understood. We therefore investigated effects of Permixon® on human prostate and detrusor smooth muscle contraction and on growth-related functions in prostate stromal cells.

MAIN METHODS

Permixon® capsules were dissolved using n-hexane. Contractions of human prostate and detrusor tissues were induced in organ bath. Proliferation (EdU assay), growth (colony formation), apoptosis and cell death (flow cytometry), viability (CCK-8) and actin organization (phalloidin staining) were studied in cultured human prostate stromal cells (WPMY-1).

KEY FINDINGS

Permixon® inhibited α₁-adrenergic and thromboxane-induced contractions in prostate tissues, and methacholine-and thromboxane-induced contractions in detrusor tissues. Endothelin-1-induced contractions were not inhibited. Neurogenic contractions were inhibited in both tissues in a concentration-dependent manner. In WPMY-1 cells, Permixon® caused concentration-dependent breakdown of actin polymerization, inhibited colony formation, reduced cell viability, and proliferation, without showing cytotoxic or pro-apoptotic effects.

SIGNIFICANCE

Our results provide a novel basis that allows, for the first time, to fully explain the ubiquitous beneficial effects of HESr in clinical trials. HESr may inhibit at least neurogenic, α₁-adrenergic and thromboxane-induced smooth muscle contraction in the prostate and detrusor, and in parallel, prostate stromal cell growth. Together, this may explain symptom improvements by Permixon® in previous clinical trials.

Phosphoproteomics identifies potential downstream targets of the integrin α2β1 inhibitor BTT-3033 in prostate stromal cells

Background

Integrin α2β1 inhibitor BTT-3033 (1-(4-fluorophenyl)-N-methyl-N-[4[[(phenylamino)carbonyl]amino]phenyl]-1H-pyrazole-4-sulfonamide) was recently reported to inhibit neurogenic and thromboxane A2-induced human prostate smooth muscle contraction, and thus represents a target with a different inhibition spectrum than that of α1-blockers in benign prostate hyperplasia (BPH) treatments. Clarifying the underlying mechanisms of the inhibition effects will provide insights into the role of integrin α2β1 in prostate contraction and enable new intracellular targets for smooth muscle contraction to be explored.

Methods

ProteomeHD was used to predict and enrich the top co-regulated proteins of integrin α2 (ITGA2). A phosphoproteomic analysis was conducted on human prostate stromal cells (WPMY-1) treated with 1 or 10 µM of BTT-3033 or solvent for controls. A clustering analysis was conducted to identify the intracellular targets that were inhibited in a dose-dependent manner. Gene ontology (GO) and annotation enrichments were conducted to examine any functional alterations and identify possible downstream targets. A Kinase-substrate enrichment analysis (KSEA) was conducted to identify kinases-substrate relationships.

Results

Enrichments of the actin cytoskeleton and guanosine triphosphatases (GTPases) signaling were predicted from the co-regulated proteins with ITGA2. LIM domain kinases, including LIM domain and actin-binding 1 (LIMA1), zyxin (ZYX), and thyroid receptor-interacting protein 6 (TRIP6), which are functionally associated with focal adhesions and the cytoskeleton, were present in the clusters with dose-dependent phosphorylation inhibition pattern. 15 substrates were dose-dependently inhibited according to the KSEA, including polo-like kinase 1 (PLK1), and GTPases signaling proteins, such as disheveled segment polarity protein 2 (DVL2).

Conclusions

In this study, we proposed that the mechanisms underlying the contractile and proliferative effects of integrin α2β1 are the LIM domain kinases, including the ZYX family, and substrates, including PLK1 and DVL2.

Polo-like Kinase 1 as an emerging drug target: structure, function and therapeutic implications

Polo-like kinase 1 (PLK1) is a conserved mitotic serine-threonine protein kinase, functions as a regulatory protein, and is involved in the progression of the mitotic cycle. It plays important roles in the regulation of cell division, maintenance of genome stability, in spindle assembly, mitosis, and DNA-damage response. PLK1 is consist of a N-terminal serine-threonine kinase domain, and a C-terminal Polo-box domain (regulatory site). The expression of PLK1 is controlled by transcription repressor in the G1 stage and transcription activators in the G2 stage of the cell cycle. Overexpression of PLK1 results in undermining of checkpoints causes excessive cellular division resulting in abnormal cell growth, leading to the development of cancer. Blocking the expression of PLK1 by an antibody, RNA interference, or kinase inhibitors, causes a subsequent reduction in the proliferation of tumour cells and induction of apoptosis in tumour cells without affecting the healthy cells, suggesting an attractive target for drug development. In this review, we discuss detailed information on expression, gene and protein structures, role in different diseases, and progress in the design and development of PLK1 inhibitors. We have performed an in-depth analysis of the PLK1 inhibitors and their therapeutic implications with special focus to the cancer therapeutics.

LncRNA DIO3OS regulated by TGF-β1 and resveratrol enhances epithelial mesenchymal transition of benign prostatic hyperplasia epithelial cells and proliferation of prostate stromal cells

Background

The etiopathogenesis of benign prostatic hyperplasia (BPH) is extremely complicated which involving epithelial-mesenchymal transition (EMT) of epithelial cells and growth of stromal cells. Long non-coding RNAs (lncRNAs) belong to a group of noncoding RNAs which has been widely studied in other diseases but rarely in BPH. Here, we intend to investigate the roles of a lncRNA DIO3 opposite strand (DIO3OS) in BPH progression.

Methods

BPH-1 cells were used to study EMT and WPMY-1 cells were applied to study proliferation induced by TGF-β1, resveratrol, DIO3OS and miRNAs.

Results

DIO3OS was over-expressed in BPH tissues and could be upregulated by Transforming growth factor beta 1 (TGF-β1) and downregulated by resveratrol. Smad2/Smad3/Smad4 complex could bind to the DIO3OS promotor region and thereby enhanced its transcription which was responsible for the regulation of TGF-β1 and resveratrol on DIO3OS expression. TGF-β1 promoted BPH-1 cells EMT and WPMY-1 cells proliferation via DIO3OS and this effect could be blocked by resveratrol. MiR-656-3p and miR-485-5p were targets of DIO3OS and DIO3OS promoted BPH-1 cells EMT and WPMY-1 cells proliferation via miR-656-3p and miR-485-5p. Connective tissue growth factor (CTGF) and zinc finger e-box binding homeobox 1 (ZEB1) were confirmed to be targets of both miR-656-3p and miR-485-5p and could be modulated by TGF-β1, resveratrol, DIO3OS, miR-656-3p and miR-485-5p.

Conclusions

DIO3OS is highly expressed in BPH tissues and regulated by TGF-β1 as well as resveratrol in a Smads dependent manner. DIO3OS facilitates BPH-1 cells EMT and WPMY-1 cells proliferation by upregulating CTGF and ZEB1 via miR-656-3p and miR-485-5p.

Purinergic smooth muscle contractions in the human prostate: estimation of relevance and characterization of different agonists

Non-adrenergic prostate smooth muscle contractions may account for the limited effectiveness of α₁-adrenoceptor antagonists, which are the first-line option for medical treatment of voiding symptoms suggestive of benign prostatic hyperplasia. In non-human prostates, purinergic agonists induce contractions reaching similar magnitudes as α₁-adrenergic contractions. However, evidence for the human prostate is highly limited, and pointed to much weaker purinergic contractions. Here, we examined contractions of different purinergic agonists in human prostate tissues. Tissues were obtained from radical prostatectomy. Contractions were studied in an organ bath, and expression of purinergic receptors was studied by RT-PCR. Electric field stimulation (EFS)–induced contractions amounted to 104% of KCl-induced contractions (95% CI: 84–124%). From all tested agonists, only ATP induced concentration-dependent contractions, reaching an average maximum of 18% (12–24%) of KCl. Maximum tensions following application of other agonists averaged to 7.1% of KCl for α,β-methylene-ATP (1.8–12.4%), 3.9% for β,γ-methylene-ATP (2.0–5.4%), 3.1% for 2-methylthio-ATP (− 0.1–6.3%), and 5.1% for ATPγS (1.0–9.2%). Responses were not affected by the P2X antagonist NF023 or the P2Y antagonist PPADS. mRNA expression of P2X1-4 correlated with expression of a marker for catecholaminergic nerves, although neither ATP, NF023, nor PPADS changed EFS-induced contractions. Correlation between expression of receptors and the smooth muscle marker calponin was not observed. Our findings point to a low relevance of purinergic contractions in the human prostate, compared to other contractile stimuli in the human prostate and compared to purinergic contractions in non-human prostates. Purinergic contractions in the human prostate are not sensitive to NF023 or PPADS.

Inhibition of neurogenic and thromboxane A2 -induced human prostate smooth muscle contraction by the integrin α2β1 inhibitor BTT-3033 and the integrin-linked kinase inhibitor Cpd22

INTRODUCTION

Prostate smooth muscle contraction is critical for etiology and treatment of lower urinary tract symptoms in benign prostatic hyperplasia (BPH). Integrins connect the cytoskeleton to membranes and cells to extracellular matrix, what is essential for force generation in smooth muscle contraction. Integrins are composed of different subunits and may cooperate with integrin-linked kinase (ILK). Here, we examined effects of inhibitors for different integrin heterodimers and ILK on contraction of human prostate tissues.

METHODS

Prostate tissues were obtained from radical prostatectomy. Integrins and ILK were detected by Western blot, real-time polymerase chain reaction (RT-PCR), and double fluorescence staining. Smooth muscle contractions of prostate strips were studied in an organ bath. Contractions were compared after application of solvent (controls), the ILK inhibitor Cpd22 (N-methyl-3-(1-(4-(piperazin-1-yl)phenyl)-5-(4'-(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-1H-pyrazol-3-yl)propanamide), the integrin α2β1 inhibitor BTT-3033 (1-(4-fluorophenyl)-N-methyl-N-[4[[(phenylamino)carbonyl]amino]phenyl]-1H-pyrazole-4-sulfonamide), or the integrin α4β1/α9β1 inhibitor BOP (N-(benzenesulfonyl)- l-prolyl- l-O-(1-pyrrolidinylcarbonyl)tyrosine sodium salt).

RESULTS

Western blot analyses of prostate tissues using antibodies raised against integrins α2b, α4, α9, β1, and ILK revealed bands matching the expected sizes of corresponding antigens. Expression of integrins and ILK was confirmed by RT-PCR. Individual variations of expression levels occurred independently from divergent degree of BPH, reflected by different contents of prostate-specific antigen. Double fluorescence staining of prostate sections using antibodies raised against integrins α2 and β1, or against ILK resulted in immunoreactivity colocalizing with calponin, suggesting localization in prostate smooth muscle cells. Electric field stimulation (EFS) induced frequency-dependent contractions, which were inhibited by Cpd22 (3 µM) and BTT-3033 (1 µM) (inhibition around 37% by Cpd22 and 46% by BTT-3033 at 32 Hz). The thromboxane A₂ analog U46619-induced concentration-dependent contractions, which were inhibited by Cpd22 and BTT-3033 (around 67% by Cpd22 and 39% by BTT-3033 at 30 µM U46619). Endothelin-1 induced concentration-dependent contractions, which were not affected by Cpd22 or BTT-3033. Noradrenaline and the α₁ -adrenergic agonists methoxamine and phenylephrine-induced concentration-dependent contractions, which were not or very slightly inhibited by Cpd22 and BTT-3033. BOP did not change EFS- or agonist-induced contraction.

CONCLUSIONS

Integrin α2β1 and ILK inhibitors inhibit neurogenic and thromboxane A₂ -induced prostate smooth muscle contraction in human BPH. A role for these targets for prostate smooth muscle contraction may appear possible.