Combination therapy in metastatic castration sensitive prostate cancer: A Systematic review and network meta-analysis.

Introduction: Studies directly comparing the different combination therapies offered to men with metastatic castration sensitive prostate cancer (mCSPC), are not available yet. This study was designed using the network meta-analysis (NMA) framework to provide a comparison of the different available options for the treatment of men with mCSPC. Methods: A systematic search was performed and the prospective randomized controlled trials reporting the overall survival (OS) or failure-free survival (FFS) were selected for review. A total of 14 studies were included in the NMA. Results: The addition of abiraterone, apalutamide, docetaxel, and docetaxel with zoledronic acid to the androgen deprivation therapy (ADT) demonstrated a significant improvement in the OS. In indirect comparison, abiraterone had a higher impact on the OS as compared to docetaxel (hazard ratio [HR]: 1.21, 95% confidence interval [CI]: 1.0-1.46) and docetaxel with zoledronic acid (HR: 1.31, 95% CI: 1.05-1.63) but not apalutamide. Furthermore, apalutamide was not different than docetaxel or docetaxel with zoledronic acid. There was a significant improvement in the FFS with the combination of abiraterone, apalutamide, docetaxel (HR: 0.61, 95% CI: 0.46-0.81), docetaxel with zoledronic acid (HR: 0.62, 95% CI: 0.43-0.9), and enzalutamide (HR: 0.39, 95% CI: 0.25-0.61) as compared to the ADT alone. Similar to the indirect comparison of OS, abiraterone outperformed docetaxel (HR: 1.66, 95% CI: 1.12-2.47), docetaxel with zoledronic acid (HR: 1.69, 95% CI: 1.06-2.68), and enzalutamide (HR: 1.06, 95% CI: 0.63-1.80), but not apalutamide in terms of impact on the FFS. Conclusion: Overall, abiraterone demonstrated better OS and FFS outcomes as compared to all the other combination strategies in this NMA.

Riluzole induces AR degradation via endoplasmic reticulum stress pathway in androgen-dependent and castration-resistant prostate cancer cells.

BACKGROUND: Prostate cancer (PCa) is diagnosed at the highest rate of all non-cutaneous male cancers in the United States. The androgen-dependent (AD) transcription factor, androgen receptor (AR), drives PCa-but inhibiting AR or androgen biosynthesis induces remission for only a short time. At which point, patients acquire more aggressive castration-resistant (CR) disease with re-activated AR-dependent signaling. To combat treatment resistance, down-regulating AR protein expression has been considered as a potential treatment strategy for CR-PCa. METHODS: AD- and CR-PCa cell lines were treated with the well-tolerated FDA-approved oral medicine, riluzole. Expression of full-length or wild-type AR (AR-FL) and constitutively active AR-splice variant 7 (AR-V7) was assessed by immunoblotting. AR-FL/AR-V7 activity was measured using qRT-PCR of AR-target genes. Cytoplasmic [Ca2+ ] levels were measured using a fluorescent Ca2+ indicator microplate assay. Markers of the endoplasmic reticulum stress (ERS) pathway and autophagy were assessed by immunoblotting. Direct interaction between AR and selective autophagy receptor p62 was demonstrated by co-immunoprecipitation. RESULTS: We demonstrate that riluzole downregulates AR-FL, mutant ARs, and AR-V7 proteins expression by protein degradation through ERS pathway and selective autophagy. Riluzole also significantly inhibited AR transcription activity by decreasing its target genes expression (PSA, TMPRSS2, and KLK2). CONCLUSIONS: We provide key mechanistic insights by which riluzole exerts its anti-tumorigenic effects and induces AR protein degradation via ERS pathways. Our findings support the potential utility of riluzole for treatment of PCa.

Characterization of fibroblast-free CWR-R1ca castration-recurrent prostate cancer cell line.

BACKGROUND: The previously established CWR-R1 cell line has been used as an in vitro model representing castration-recurrent prostate cancer. Microscopic observation of subconfluent cells demonstrated two distinct cellular morphologies: polygonal closely aggregated epithelial cells surrounded by bipolar fibroblastic cells with long processes. This study sought to establish and characterize a fibroblast-free derivative of the CWR-R1 cell line. METHODS: The CWR-R1ca cell line was established from CWR-R1 cells by removing fibroblasts using multiple cycles of short-term trypsinization, cloning, and pooling single-cell colonies. Authentication of fibroblast-free CWR-R1ca cells was demonstrated by analyzing the expression of cytodifferentiation and prostate-associated markers, DNA and cytogenetic profiling, and growth pattern in the absence or presence of androgen. RESULTS: CWR-R1ca is an androgen-sensitive cell line that expresses the androgen receptor (AR) and its splice variant 7 and the luminal epithelia markers, CK-8, CK-18, and c-Met. CWR-R1fb fibroblasts isolated from CWR-R1 cells express AR, hepatocyte growth factor-α, and mouse ß-actin but not AR-V7 or epithelial markers. Cytogenetic analysis of CWR-R1ca cells revealed a hyperdiploid male with numerical gains in chromosomes 1, 7, 8, 10, 11, and 12, deletion of one chromosome 2 allele, structural abnormalities that include der(1)t(1:4), der(4)t(2:4), der(10)t(4:10), and an unbalanced reciprocal translocation between chromosome 6 and 14. DNA-profiling revealed that CWR-R1ca cells had significant short-tandem repeat marker homology with CWR22Pc and CWR22Rv1 cell lines, which indicated lineage derivation from CWR22 prostate cancer xenografts. CWR-R1ca cells were responsive to the growth stimulatory effects of dihydrotestosterone (DHT) in the femtomolar range. CONCLUSION: This study establishes CWR-R1ca cells as a fibroblast-free derivative of the castration-recurrent CWR-R1 cell line. Prostate 76:1067-1077, 2016. © 2016 Wiley Periodicals, Inc.

Mitochondrial dysfunction-mediated apoptosis resistance associates with defective heat shock protein response in African-American men with prostate cancer.

BACKGROUND: African-American (AA) patients with prostate cancer (PCa) respond poorly to current therapy compared with Caucasian American (CA) PCa patients. Although underlying mechanisms are not defined, mitochondrial dysfunction is a key reason for this disparity. METHODS: Cell death, cell cycle, and mitochondrial function/stress were analysed by flow cytometry or by Seahorse XF24 analyzer. Expression of cellular proteins was determined using immunoblotting and real-time PCR analyses. Cell survival/motility was evaluated by clonogenic, cell migration, and gelatin zymography assays. RESULTS: Glycolytic pathway inhibitor dichloroacetate (DCA) inhibited cell proliferation in both AA PCa cells (AA cells) and CA PCa cells (CA cells). AA cells possess reduced endogenous reactive oxygen species, mitochondrial membrane potential (mtMP), and mitochondrial mass compared with CA cells. DCA upregulated mtMP in both cell types, whereas mitochondrial mass was significantly increased in CA cells. DCA enhanced taxol-induced cell death in CA cells while sensitising AA cells to doxorubicin. Reduced expression of heat shock proteins (HSPs) was observed in AA cells, whereas DCA induced expression of CHOP, C/EBP, HSP60, and HSP90 in CA cells. AA cells are more aggressive and metastatic than CA cells. CONCLUSIONS: Restoration of mitochondrial function may provide new option for reducing PCa health disparity among American men.

ROBO1, a tumor suppressor and critical molecular barrier for localized tumor cells to acquire invasive phenotype: study in African-American and Caucasian prostate cancer models.

High-risk populations exhibit early transformation of localized prostate cancer (CaP) disease to metastasis which results in the mortality of such patients. The paucity of knowledge about the molecular mechanism involved in acquiring of metastatic behavior by primary tumor cells and non-availability of reliable phenotype-discriminating biomarkers are stumbling blocks in the management of CaP disease. Here, we determine the role and translational relevance of ROBO1 (an organogenesis-associated gene) in human CaP. Employing CaP-progression models and prostatic tissues of Caucasian and African-American patients, we show that ROBO1 expression is localized to cell-membrane and significantly lost in primary and metastatic tumors. While Caucasians exhibited similar ROBO1 levels in primary and metastatic phenotype, a significant difference was observed between tumor phenotypes in African-Americans. Epigenetic assays identified promoter methylation of ROBO1 specific to African-American metastatic CaP cells. Using African-American CaP models for further studies, we show that ROBO1 negatively regulates motility and invasiveness of primary CaP cells, and its loss causes these cells to acquire invasive trait. To understand the underlying mechanism, we employed ROBO1-expressing/ROBO1-C2C3-mutant constructs, immunoprecipitation, confocal-microscopy and luciferase-reporter techniques. We show that ROBO1 through its interaction with DOCK1 (at SH3-SH2-domain) controls the Rac-activation. However, loss of ROBO1 results in Rac1-activation which in turn causes E-Cadherin/ß-catenin cytoskeleton destabilization and induction of cell migration. We suggest that ROBO1 is a predictive biomarker that has potential to discriminate among CaP types, and could be exploited as a molecular target to inhibit the progression of disease as well as treat metastasis in high-risk populations such as African-Americans.

Androgen-responsive serum response factor target genes regulate prostate cancer cell migration.

Progression of prostate cancer (CaP) relies on androgen receptor (AR) signaling, but AR-dependent events that underlie the lethal phenotype remain unknown. Recently, an indirect mechanism of androgen action in which effects of AR on CaP cells are mediated by Serum Response Factor (SRF) has been identified. This is the first mode of androgen action to be associated with aggressive CaP and disease recurrence. The manner in which androgen-responsive SRF activity controls aggressive CaP cell behavior is unknown. Here, the contribution of two representative SRF effector genes that are underexpressed, calponin 2 (CNN2), or overexpressed, sidekick-homolog 1 (SDK1), in clinical CaP specimens is studied. AR- and SRF- dependency of CNN2 and SDK1 expression was verified using synthetic and natural androgens, antiandrogens, and small interfering RNAs targeting AR or SRF, and evaluating the kinetics of androgen induction and SRF binding to endogenously and exogenously expressed regulatory gene regions in AR-positive CaP model systems that mimic the transition from androgen-stimulated to castration-recurrent disease. Small interfering RNA-mediated deregulation of CNN2 or SDK1 expression did not affect CaP cell proliferation or apoptosis but had marked effects on CaP cell morphology and actin cytoskeleton organization. Loss of CNN2 induced cellular protrusions and increased CaP cell migration, whereas silencing of SDK1 led to cell rounding and blunted CaP cell migration. Changes in cell migration did not involve epithelial-mesenchymal transition but correlated with altered ß1-integrin expression. Taken together, individual androgen-responsive SRF target genes affect CaP cell behavior by modulating cell migration, which may have implications for therapeutic intervention downstream of AR and SRF.

Polycyclic aromatic hydrocarbons-induced ROS accumulation enhances mutagenic potential of T-antigen from human polyomavirus JC.

Polycyclic aromatic hydrocarbons (PAHs) are the products of incomplete combustion of organic materials, which are present in cigarette smoke, deep-fried food, and in natural crude oil. Since PAH-metabolites form DNA adducts and cause oxidative DNA damage, we asked if these environmental carcinogens could affect transforming potential of the human Polyomavirus JC oncoprotein, T-antigen (JCV T-antigen). We extracted DMSO soluble PAHs from Deepwater Horizon oil spill in the Gulf of Mexico (oil-PAHs), and detected several carcinogenic PAHs. The oil-PAHs were tested in exponentially growing cultures of normal mouse fibroblasts (R508), and in R508 stably expressing JCV T-antigen (R508/T). The oil-PAHs were cytotoxic only at relatively high doses (1:50-1:100 dilution), and at 1:500 dilution the growth and cell survival rates were practically unaffected. This non-toxic dose triggered however, a significant accumulation of reactive oxygen species (ROS), caused oxidative DNA damage and the formation of DNA double strand breaks (DSBs). Although oil-PAHs induced similar levels of DNA damage in R508 and R508/T cells, only T-antigen expressing cells demonstrated inhibition of high fidelity DNA repair by homologous recombination (HRR). In contrast, low-fidelity repair by non-homologous end joining (NHEJ) was unaffected. This potential mutagenic shift between DNA repair mechanisms was accompanied by a significant increase in clonal growth of R508/T cells chronically exposed to low doses of the oil-PAHs. Our results indicate for the first time carcinogenic synergy in which oil-PAHs trigger oxidative DNA damage and JCV T-antigen compromises DNA repair fidelity.

Natural history, and impact of surgery and radiation on survival outcomes of men diagnosed with low-grade prostate cancer at ≤ 55 years of age: a 25-year follow-up of > 60,000 men.

PURPOSE: Low-grade prostate cancer has low mortality rates at 10 years; however, it is unclear if the response is sustained for up to 25 years of follow-up. METHODS: Using Surveillance, Epidemiology, and End Results database, the overall and cancer-specific mortality rates were compared among men ≤ 55 years of age diagnosed with low-grade prostate cancer that either had radical prostatectomy, radiotherapy, or no known treatment. RESULTS: Of the 62,772 men diagnosed with low-grade prostate cancer between 1975 and 2016, about 60%, 20% and 20% of men underwent radical prostatectomy, radiotherapy, and no known treatment, respectively. At a median follow-up of 10 years, almost 2% and 7% of men died of prostate cancer and other causes, respectively. The overall mortality was significantly better in radical prostatectomy group compared to no known treatment group (HR 1.99, CI 1.84-2.15, P value < 0.001), but not between the radiotherapy and no known treatment groups. Moreover, the overall and cancer-specific mortality rates in the radiotherapy group were almost two and three times compared to the radical prostatectomy group, respectively (HR 2.15, CI 2.01-2.29, P value < 0.001 for overall mortality and HR 2.87, CI 2.5-3.29, P value < 0.001 for cancer-specific mortality). CONCLUSIONS: The study confirms low mortality rates in men diagnosed with low-grade prostate cancer for over 25 years' follow-up. While radical prostatectomy improves survival significantly compared to no known treatment, radiotherapy is associated with an increase in overall and cancer-specific mortality, which may be related to long-term toxicities.

Extramural venous invasion: a novel magnetic resonance imaging biomarker for adverse pathology in bladder cancer.

Extramural venous invasion (EMVI) recognized on magnetic resonance imaging (MRI) is an unequivocal biomarker for detecting adverse outcomes in rectal cancer: however it has not yet been explored in the area of bladder cancer. In this study, we assessed the feasibility of identifying EMVI findings on MRI in patients with bladder cancer and its avail in identifying adverse pathology. In this single-institution retrospective study, the MRI findings inclusive of EMVI was described in patients with bladder cancer that had available imaging between January 2018 and June 2020. Patient demographic and clinical information were retrieved from our electronic medical records system. Histopathologic features frequently associated with poor outcomes including lymphovascular invasion (LVI), variant histology, muscle invasive bladder cancer (MIBC), and extravesical disease (EV) were compared to MRI-EMVI. A total of 38 patients were enrolled in the study, with a median age of 73 years (range 50-101), 76% were male and 23% were females. EMVI was identified in 23 (62%) patients. There was a significant association between EMVI and MIBC (OR = 5.30, CI = 1.11-25.36; P = 0.036), and extravesical disease (OR = 17.77, CI = 2.37-133; P = 0.005). We found a higher probability of presence of LVI and histologic variant in patients with EMVI. EMVI had a sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of 90%, 73%, 94% and 63% respectively in detecting extravesical disease. Our study suggests, EMVI may be a useful biomarker in bladder cancer imaging, is associated with adverse pathology, and could be potentially integrated in the standard of care with regards to MRI reporting systems. A larger study sample size is further warranted to assess feasibility and applicability.

Serum prosaposin levels are increased in patients with advanced prostate cancer.

BACKGROUND: We previously cloned prosaposin (PSAP) from metastatic castrate-resistant prostate cancer (mCRPCa) cells and demonstrated its genomic amplification and/or overexpression in metastatic PCa cell lines, xenografts, and lymph node metastases. The clinicohistopathological significance of serum PSAP levels and its tissue expression and association with predictive or prognostic variable in primary or advanced PCa are not known. METHODS: We examined PSAP expression by immunohistochemical staining during early embryogenic development of the prostate and within a large tissue microarray which included 266 benign and malignant prostate tissues. In addition, serum PSAP levels in the age-adjusted normal male population and in 154 normal individuals and patients with primary or mCRPCa were measured by an ELISA assay. RESULTS: Univariate and multivariate analyses revealed a significant and inverse association between PSAP expression and clinical stages II and III tumors, dominant Gleason patterns 3 and 4, and seminal vesicle invasion. In the normal male population, the lowest serum PSAP level was detected before puberty, peaked at the most reproductive age group (20- to 39-year old), and then, decreased to a range between the two groups for men above 40-year old. Regardless of age and when compared with normal individuals, serum PSAP levels significantly decreased in primary organ-confined PCa, but increased in those with mCRPCa. CONCLUSION: Our results show that PSAP has the potential to differentiate between primary and advanced PCa. Additional large-scale studies are needed to define the usefulness of tissue expression or serum PSAP levels as a diagnostic or prognostic marker or as a therapeutic target in PCa.

Poly(ADP-ribose) polymerase-1 is a determining factor in Crm1-mediated nuclear export and retention of p65 NF-kappa B upon TLR4 stimulation.

The role of NF-kappaB in the expression of inflammatory genes and its participation in the overall inflammatory process of chronic diseases and acute tissue injury are well established. We and others have demonstrated a critical involvement of poly(ADP-ribose) polymerase (PARP)-1 during inflammation, in part, through its relationship with NF-kappaB. However, the mechanism by which PARP-1 affects NF-kappaB activation has been elusive. In this study, we show that PARP-1 inhibition by gene knockout, knockdown, or pharmacologic blockade prevented p65 NF-kappaB nuclear translocation in smooth muscle cells upon TLR4 stimulation, NF-kappaB DNA-binding activity, and subsequent inducible NO synthase and ICAM-1 expression. Such defects were reversed by reconstitution of PARP-1 expression. PARP-1 was dispensable for LPS-induced IkappaBalpha phosphorylation and subsequent degradation but was required for p65 NF-kappaB phosphorylation. A perinuclear p65 NF-kappaB localization in LPS-treated PARP-1(-/-) cells was associated with an export rather an import defect. Indeed, whereas PARP-1 deficiency did not alter expression of importin alpha3 and importin alpha4 and their cytosolic localization, the cytosolic levels of exportin (Crm)-1 were increased. Crm1 inhibition promoted p65 NF-kappaB nuclear accumulation as well as reversed LPS-induced p65 NF-kappaB phosphorylation and inducible NO synthase and ICAM-1 expression. Interestingly, p65 NF-kappaB poly(ADP-ribosyl)ation decreased its interaction with Crm1 in vitro. Pharmacologic inhibition of PARP-1 increased p65 NF-kappaB-Crm1 interaction in LPS-treated smooth muscle cells. These results suggest that p65 NF-kappaB poly(ADP-ribosyl)ation may be a critical determinant for the interaction with Crm1 and its nuclear retention upon TLR4 stimulation. These results provide novel insights into the mechanism by which PARP-1 promotes NF-kappaB nuclear retention, which ultimately can influence NF-kappaB-dependent gene regulation.

An Indirect Comparison of Newer Minimally Invasive Treatments for Benign Prostatic Hyperplasia: A Network Meta-Analysis Model.

Objective: This study was designed to provide an indirect comparison of the urinary and sexual domain outcomes and complications after newer minimally invasive surgical therapy (MIST) of Aquablation, Rezum, and UroLift for benign prostatic hyperplasia (BPH) for transurethral resection of prostate (TURP). Methods: We searched Embase, Medline, and Cochrane in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, in December 2019. Only randomized clinical trials (RCTs) that reported outcomes after treatment of BPH for prostate less than 80 g with Aquablation, Rezum, or UroLift were included in the analysis. Results: A total of four RCTs reporting the outcomes after treatment with newer MIST for BPH were identified. Patients undergoing the resective procedures, that is, TURP and Aquablation, had greater improvement in urinary domain outcomes: International Prostate Symptom Score, quality of life, peak flow rate, and postvoiding residual compared to patients undergoing nonresective procedures: UroLift and Rezum. Patients in UroLift group maintained a higher sexual function domain score compared to TURP, but not Aquablation. Our multiple comparison analysis did not reveal a significant difference in urinary and sexual domain scores between patients undergoing UroLift and Rezum at 24 months of follow-up. Conclusions: Aquablation and TURP necessitate general or regional anesthesia and both produced significantly better urinary domain scores compared to Rezum and UroLift. On the other hand, UroLift demonstrated better sexual function domain scores compared to TURP, but not Aquablation. There was no significant difference in urinary domain scores between UroLift and Rezum at 24 months of follow-up.

Pathology grade influences competing mortality risks in elderly men with prostate cancer.

BACKGROUND: Recent guidelines recommend active management of prostate cancer (CaP), especially high-risk disease, in elderly men. However, descriptive data from a large cohort with extended follow up on the risk of death from CaP in men diagnosed over 70 years of age and its relationship to Gleason score (GS) and serum prostate specific antigen (PSA) level is lacking. Using the Surveillance, Epidemiology, and End Results database, we evaluated the influence of GS and serum PSA levels on the risks of mortality from PC (PCM) and mortality from other causes in localized (LPC) and metastatic (MPC) disease in elderly population. METHODS: Men diagnosed with PC over 70 years of age between 2004 and 2016 were divided into LPC and MPC groups, categorized by age: 70-74, 75-79, 80-84, 85-89, and ≥90 years and stratified by GS <7, 7, and >7, and serum PSA level <4, 4-10, 10-20, 20-50, and >50 ng/mL. Competing risk estimates for PCM and mortality from other causes were generated for both groups. RESULTS: Of the 85,649 men, 85.5 % were LPC at diagnosis. Overall, at a median follow up of 4 years, 15% of the men had died including a third from PC. While <15% of men with GS ≤7 died from PC, the PCM was >30% in men with GS >7 in LPC group, which accounted for almost half of total deaths for age 70-84 years. The GS >7 was also significantly associated with PCM in men with MPC. Furthermore, PCM directly correlated with serum PSA levels, with mortality rates reaching up to 50% and 70% for PSA >50 ng/dl for LPC and MPC, respectively. CONCLUSIONS: There is a substantial risk of dying in men diagnosed with LPC over 70 years of age with GS >7 or a serum PSA >20 ng/mL. Furthermore, the risk for death for MPC directly correlated with GS with PCM increasing from 10%-30% for GS ≤7 to >50% for GS >7. The data, in conjunction with other clinical parameters such as comorbidities could be used to counsel elderly men on management options of PC for both localized and metastatic PC.

Intracorporeal versus extracorporeal urinary diversion following robot-assisted radical cystectomy: a meta-analysis, cumulative analysis, and systematic review.

Over the last decade, the increased utilization of robot-assisted radical cystectomy (RARC) in the surgical treatment of muscle-invasive bladder cancer has led to an uptrend in intracorporeal urinary diversions (ICUD). However, the operative results comparing ICUD to extracorporeal urinary diversion (ECUD) have varied widely. We performed a meta-analysis to analyze perioperative outcomes and complications of ICUD compared to ECUD following RARC. This study is registered at International Prospective Register of Systematic Reviews (PROSPERO) CRD42020164074. A systematic literature review was conducted using PubMed, EMBASE, and Cochrane databases in August 2019. A total of six studies comparing ICUD vs ECUD were identified and meta-analysis was conducted on these studies. In addition, a cumulative analysis was also performed on 83 studies that reported perioperative outcomes after RARC and ICUD or ECUD. The Weighed Mean Difference of operative time and blood loss between ICUD and ECUD group was (16; 95% confidence interval - 34 to 66) and (- 86; 95% confidence interval - 124 to - 48), respectively. ICUD and ECUD had comparable early (30-day) and mid-term (30-90-day) complication rate (RR 1.19; 95% confidence interval 0.71-2.0; p = 0.5) and (RR 0.91; 95% confidence interval 0.71-1.15 p = 0.4) respectively. In the 83 studies that were included in the cumulative analysis, the mean operative time for ileal conduit and neobladders by ICUD were 307 and 428 min, respectively, compared to ECUD 428 and 426 min, respectively. ICUD and ECUD have comparable short- and mid-term complication rate. The ICUD group has lower blood loss and lower rate of blood transfusion compared to ECUD.

Prosaposin down-modulation decreases metastatic prostate cancer cell adhesion, migration, and invasion.

BACKGROUND: Factors responsible for invasive and metastatic progression of prostate cancer (PCa) remain largely unknown. Previously, we reported cloning of prosaposin (PSAP) and its genomic amplification and/or overexpression in several androgen-independent metastatic PCa cell lines and lymph node metastases. PSAP is the lysosomal precursor of saposins, which serve as activators for lysosomal hydrolases involved in the degradation of ceramide (Cer) and other sphingolipids. RESULTS: Our current data show that, in metastatic PCa cells, stable down-modulation of PSAP by RNA-interference via a lysosomal proteolysis-dependent pathway decreased beta1A-integrin expression, its cell-surface clustering, and adhesion to basement membrane proteins; led to disassembly of focal adhesion complex; and decreased phosphorylative activity of focal adhesion kinase and its downstream adaptor molecule, paxillin. Cathepsin D (CathD) expression and proteolytic activity, migration, and invasion were also significantly decreased in PSAP knock-down cells. Transient-transfection studies with beta1A integrin- or CathD-siRNA oligos confirmed the cause and effect relationship between PSAP and CathD or PSAP and Cer-beta1A integrin, regulating PCa cell migration and invasion. CONCLUSION: Our findings suggest that by a coordinated regulation of Cer levels, CathD and beta1A-integrin expression, and attenuation of "inside-out" integrin-signaling pathway, PSAP is involved in PCa invasion and therefore might be used as a molecular target for PCa therapy.

Optimal transactivation by Epstein-Barr nuclear antigen 1 requires the UR1 and ATH1 domains.

Epstein-Barr nuclear antigen 1 (EBNA1) is essential for Epstein-Barr virus to immortalize naïve B cells. EBNA1 transactivates viral promoters for genes that are necessary for immortalization when it is bound to a cluster of 20 cognate binding sites, termed the family of repeats. A region of EBNA1 from amino acids (aa) 40 to 89, termed linking region 1 (LR1), has been identified previously as being sufficient for transactivation. LR1 contains two domains that are conserved in the EBNA1 orthologs of other gamma herpesviruses. The first of these, termed unique region 1 (UR1), corresponds to aa 65 to 89 of EBNA1. UR1 is necessary for transactivation and contains a conserved recognition site for cyclic AMP-dependent protein kinase (PKA), corresponding to serine 78 of EBNA1. We have pharmacologically modulated PKA activity to determine if PKA controls EBNA1's ability to transactivate. Our results indicate that PKA activators and inhibitors do not affect transactivation by EBNA1. In addition, site-directed mutagenesis demonstrates that transactivation is not influenced by the phosphorylation status of serine 78 in the UR1 domain. The second conserved domain within LR1 is a glycine-arginine repeat, corresponding to aa 40 to 54 of EBNA1. This domain, termed ATH1, functions as an AT-hook, a DNA-binding motif found in architectural transcription factors such as HMGA1a. We demonstrate that deletion of the ATH1 domain decreases EBNA1 transactivation ability, which is consistent with a transcriptional role for ATH1. Furthermore, transactivation is restored when ATH1 is replaced by equivalent AT-hook motifs from HMGA1a. Our data strongly indicate a role for AT-hooks in EBNA1's ability to transactivate, a function necessary for EBV to immortalize naïve B-cells.

Combination Therapy for Metastatic Renal Cell Carcinoma: A Systematic Review and Network Meta-analysis.

INTRODUCTION: Randomized clinical trials have shown combination therapy to be superior in progression-free survival (PFS) rates when compared with sunitinib alone. However, there have been no direct comparisons among the combination strategies making it unclear as to which may be the preferred option. We performed a network meta-analysis of the combination therapy (immune checkpoint inhibitor plus axitinib or bevacizumab) used in metastatic renal cell carcinoma (mRCC) and provided a rank order preference based on PFS, and adverse events (AEs). MATERIALS AND METHODS: A systematic search on the treatment of mRCC using combination therapy till July 2019 was done. Studies reporting on combination therapies with immune checkpoint inhibitor plus axitinib or bevacizumab for mRCC were selected. Frequentist method was used for rank order generation. RESULTS: A total of 3 studies consisting of 2672 patients were selected. All combination therapies demonstrated improved PFS when compared with sunitinib alone. The rank order for PFS showed combination of pembrolizumab plus axitinib had the highest probability of favorability followed by avelumab plus axitinib and atezolizumab plus bevacizumab (surface under the cumulative ranking 0.9, 0.7, and 0.4, respectively). For AEs, pembrolizumab plus axitinib had the least AEs ≥grade 3, followed by avelumab plus axitinib and atezolizumab plus bevacizumab (surface under the cumulative ranking 0, 0.5, 1.0). CONCLUSIONS: This network meta-analysis demonstrates that combination of pembrolizumab plus axitinib may be the preferred option based on efficacy and side effect profile compared with avelumab plus axitinib or atezolizumab plus bevacizumab. However, all the 3 combination strategies were superior to sunitinib alone in improving PFS in patients with mRCC.

Comparative efficacy of apalutamide darolutamide and enzalutamide for treatment of non-metastatic castrate-resistant prostate cancer: A systematic review and network meta-analysis.

INTRODUCTION: Studies using apalutamide, enzalutamide, or darolutamide have shown improved metastasis free survival (MFS) rates, leaving clinicians with a dilemma of choosing one over the other, for nonmetastatic castration recurrent prostate cancer (nmCRPC). We performed a network meta-analysis to provide an indirect comparison of oncologic outcomes and adverse events (AEs) of these medications. MATERIAL AND METHODS: We searched PubMed, MEDLINE, and SCOPUS databases, for studies reporting apalutamide, enzalutamide, or darolutamide until January 25, 2020. Results were input into an EndNote library, and data were extracted into a predefined template. Progression free survival (PFS) was defined as radiologic progression or death. Network meta-analysis was done using R and meta-analysis was performed with RevMan v. 5. Surface under the cumulative ranking (SUCRA) value was used to provide rank probabilities. RESULTS: We found 3 studies reporting results for apalutamide, enzalutamide, and darolutamide. MFS was significantly lower in patients receiving darolutamide compared to both apalutamide (hazard ratio [HR]: 0.73, 95% confidence interval [CI]: 0.55-0.97) and enzalutamide (HR: 0.71, 95% CI: 0.54-0.93). MFS was similar for enzalutamide and apalutamide (HR: 0.97, 95% CI: 0.73-1.28). In PFS, apalutamide showed a slightly higher rate compared to darolutamide (HR: 0.76, 95% CI: 0.59-0.99). There was no difference in overall survival (OS) between any of the medications. There was no statistically significant difference in AEs profile of the 3 medications. However, darolutamide had the highest SUCRA value and probability of being the most preferred medication based on AEs profile. CONCLUSION: Enzalutamide and apalutamide had similar and higher MFS rate in indirect comparison with darolutamide. In cases where AEs are concerning, darolutamide might be the preferred agent.

A Systematic Review and Meta-Analysis of Methods Used to Reduce Infectious Complications Following Transrectal Prostate Biopsy.

We reviewed and analyzed the most effective methods to reduce infectious complications (IC) after transrectal prostate biopsy (TRPB). We included only prospective randomized-controlled trials in the analysis. The analysis neither demonstrated any superiority of fluoroquinolones over other antibiotic classes nor of targeted antibiotics over empiric regimens in men undergoing TRPB. However, longer course antibiotics (3 days or more) compared to single dose or day regimens, combination of fluoroquinolones with aminoglycosides compared to fluoroquinolones alone and povidone-iodine rectal cleansing compared to control significantly reduced IC following TRPB. A combination of addition of aminoglycosides to oral antibiotics for 3 days along with povidone-iodine rectal cleansing may be an optimum strategy to minimize the risk of IC after TRPB.

Predictive and targeting value of IGFBP-3 in therapeutically resistant prostate cancer.

BACKGROUND: Our previous studies demonstrated that a novel quinazoline derivative, DZ-50, inhibited prostate cancer epithelial cell invasion and survival by targeting insulin-like-growth factor binding protein-3 (IGFBP-3) and mediating epithelial-mesenchymal transition (EMT) conversion to mesenchymal-epithelial transition (MET). This study investigated the therapeutic value of DZ-50 agent in in vitro and in vivo models of advanced prostate cancer and the ability of the compound to overcome resistance to antiandrogen (enzalutamide) in prostate tumors. APPROACH: LNCaP and LNCaP-enzalutamide resistant human prostate cancer (LNCaP-ER) cells, as well as 22Rv1 and enzalutamide resistant, 22Rv1-ER were used as cell models. The effects of DZ-50 and the antiandrogen, enzalutamide (as single agents or in combination) on cell death, EMT-MET interconversion, and expression of IGFBP3 and the androgen receptor (AR), were examined. The TRAMP mouse model of prostate cancer progression was used as a pre-clinical model. Transgenic mice (20-wks of age) were treated with DZ-50 (100 mg/kg for 2 wks, oral gavage daily) and prostate tumors were subjected to immunohistochemical assessment of apoptosis, cell proliferation, markers of EMT and differentiation and IGFBP-3 and AR expression. A tissue microarray (TMA) was analyzed for expression of IGBP-3, the target of DZ-50 and its association with tumor progression and biochemical recurrence. RESULTS: We found that treatment with DZ-50 enhanced the anti-tumor response to the antiandrogen via promoting EMT to MET interconversion, in vitro. This DZ-50-mediated phenotypic reversal to MET leads to prostate tumor re-differentiation in vivo, by targeting nuclear IGFBP-3 expression (without affecting AR). Analysis of human prostate cancer specimens and TCGA patient cohorts revealed that overexpression of IGBP-3 protein correlated with tumor recurrence and poor patient survival. CONCLUSIONS: These findings provide significant new insights into (a) the predictive value of IGFBP-3 in prostate cancer progression and (b) the antitumor action of DZ-50, [in combination or sequencing with enzalutamide] as a novel approach for the treatment of therapeutically resistant prostate cancer.