Deletion of protein tyrosine phosphatase SHP-1 restores SUMOylation of podocin and reverses the progression of diabetic kidney disease.

Both clinical and experimental data suggest that podocyte injury is involved in the onset and progression of diabetic kidney disease (DKD). Although the mechanisms underlying the development of podocyte loss are not completely understood, critical structural proteins such as podocin play a major role in podocyte survival and function. We have reported that the protein tyrosine phosphatase SHP-1 expression increased in podocytes of diabetic mice and glomeruli of patients with diabetes. However, the in vivo contribution of SHP-1 in podocytes is unknown. Conditional podocyte-specific SHP-1-deficient mice (Podo-SHP-1-/-) were generated to evaluate the impact of SHP-1 deletion at four weeks of age (early) prior to the onset of diabetes and after 20 weeks (late) of diabetes (DM; Ins2+/C96Y) on kidney function (albuminuria and glomerular filtration rate) and kidney pathology. Ablation of the SHP-1 gene specifically in podocytes prevented and even reversed the elevated albumin/creatinine ratio, glomerular filtration rate progression, mesangial cell expansion, glomerular hypertrophy, glomerular basement membrane thickening and podocyte foot process effacement induced by diabetes. Moreover, podocyte-specific deletion of SHP-1 at an early and late stage prevented diabetes-induced expression of collagen IV, fibronectin, transforming growth factor-ß, transforming protein RhoA, and serine/threonine kinase ROCK1, whereas it restored nephrin, podocin and cation channel TRPC6 expression. Mass spectrometry analysis revealed that SHP-1 reduced SUMO2 post-translational modification of podocin while podocyte-specific deletion of SHP-1 preserved slit diaphragm protein complexes in the diabetic context. Thus, our data uncovered a new role of SHP-1 in the regulation of cytoskeleton dynamics and slit diaphragm protein expression/stability, and its inhibition preserved podocyte function preventing DKD progression.

The Burden of Uncontrolled Cardiovascular Risk Factors in Men With Prostate Cancer: A RADICAL-PC Analysis.

Background: Cardiovascular disease (CVD) incidence is higher in men with prostate cancer (PC) than without. Objectives: We describe the rate and correlates of poor cardiovascular risk factor control among men with PC. Methods: We prospectively characterized 2,811 consecutive men (mean age 68 ± 8 years) with PC from 24 sites in Canada, Israel, Brazil, and Australia. We defined poor overall risk factor control as ≥3 of the following: suboptimal low-density lipoprotein cholesterol (>2 mmol/L if Framingham Risk Score [FRS] ≥15 and ≥3.5 mmol/L if FRS <15), current smoker, physical inactivity (<600 MET min/wk), suboptimal blood pressure (BP) (≥140/90 mm Hg if no other risk factors, systolic BP ≥120 mm Hg if known CVD or FRS ≥15, and ≥130/80 mm Hg if diabetic), and waist:hip ratio >0.9. Results: Among participants (9% with metastatic PC and 23% with pre-existing CVD), 99% had ≥1 uncontrolled cardiovascular risk factor, and 51% had poor overall risk factor control. Not taking a statin (odds ratio [OR]: 2.55; 95% CI: 2.00-3.26), physical frailty (OR: 2.37; 95% CI: 1.51-3.71), need for BP drugs (OR: 2.36; 95% CI: 1.84-3.03), and age (OR per 10-year increase: 1.34; 95% CI: 1.14-1.59) were associated with poor overall risk factor control after adjustment for education, PC characteristics, androgen deprivation therapy, depression, and Eastern Cooperative Oncology Group functional status. Conclusions: Poor control of modifiable cardiovascular risk factors is common in men with PC, highlighting the large gap in care and the need for improved interventions to optimize cardiovascular risk management in this population.

Enhanced SHP-1 Expression in Podocyturia Is Associated with Kidney Dysfunction in Patients with Diabetes.

Background: Diabetic kidney disease (DKD) remains the leading cause of end stage kidney disease worldwide. Despite significant advances in kidney care, there is a need to improve noninvasive techniques to predict the progression of kidney disease better for patients with diabetes. After injury, podocytes are shed in urine and may be used as a biologic tool. We previously reported that SHP-1 is upregulated in the kidney of diabetic mice, leading to podocyte dysfunction and loss. Our objective was to evaluate the expression levels of SHP-1 in urinary podocytes and kidney tissues of patients with diabetes. Methods: In this prospective study, patients with and without diabetes were recruited for the quantification of SHP-1 in kidney tissues, urinary podocytes, and peripheral blood monocytes. Immunochemistry and mass spectrometry techniques were applied for kidney tissues. Urinary podocytes were counted, and expression of SHP-1 and podocyte markers were measured by quantitative PCR. Results: A total of 66 participants (diabetic n=48, nondiabetic n=18) were included in the analyses. Diabetes was associated with increased SHP-1 expression in kidney tissues (P=0.03). Nephrin and podocin mRNA was not significantly increased in urinary podocytes from patients with diabetes compared with those without diabetes, whereas levels of SHP-1 mRNA expression significantly correlated with HbA1c and estimated glomerular filtration rate (eGFR). Additionally, follow-up (up to 2 years post recruitment) evaluation indicated that SHP-1 mRNA expression continued to increase with eGFR decline. Conclusions: Levels of SHP-1 in urinary podocytes may serve as an additional marker of glomerular disease progression in this population.

PACE4-altCT isoform of proprotein convertase PACE4 as tissue and plasmatic biomarker for prostate cancer.

The proprotein convertase PACE4 has demonstrated value as a viable therapeutic target in prostate cancer (PCa). A novel isoform named PACE4-altCT, which arises in neoplastic lesions, plays an important role in tumor progression and has been validated as a pharmacological target. With the discovery of its overexpression in PCa and the alternative splicing of its pre-RNA to generate an oncogenic C-terminally modified isoform named PACE4-altCT, understanding and validating its value as a potential biomarker is of great interest either from prognostic or targeted therapy intervention. Expression of ERG in LNCaP cells was used to investigate the relationship between ERG expression occurring in PCa cells and PACE4-altCT expression by Western blot and qPCR. Using immunohistochemistry, the expression levels of PACE4 isoforms in patient tissues were investigated and correlated with ERG tumor status and Gleason score. An ELISA method was developed using affinity purified recombinant protein and used for quantitative analysis of plasma concentrations of PACE4-altCT and used for correlation. In contrast with the consensual isoform, PACE4-altCT was only strongly overexpressed in prostate cancer patients, correlated with ERG expression levels. Despite its intracellular retention PACE4-altCT could be detected in the plasma of most patients with prostate cancer, whereas it was only found at low levels in normal patients whereas total plasmatic PACE4 levels did not vary significantly between groups. Our study demonstrates that PACE4-altCT is strongly overexpressed in prostate cancer using both immunohistochemical and ELISA techniques and may have some interesting potential as a biomarker.

Real-world evidence in patient-reported outcomes (PROs) of metastatic castrate-resistant prostate cancer (mCRPC) patients treated with abiraterone acetate + prednisone (AA+P) across Canada: Final results of COSMiC.

INTRODUCTION: Abiraterone acetate plus prednisone (AA+P) has shown to significantly improve survival. COSMiC, a Canadian Observational Study in Metastatic Cancer of the Prostate, set out to prospectively amass real-world data on metastatic castration-resistant prostate cancer (mCRPC) patients managed with AA+P in Canada. Herein, we report their patient-reported outcomes (PROs). METHODS: After a median followup of 67.1 weeks, 254 patients were enrolled across 39 sites. Functional Assessment of Cancer Therapy-Prostate (FACT-P), Montreal Cognitive Assessment (MoCA), Brief Pain Inventory-Short Form (BPI-SF), Brief Fatigue Inventory (BFI), and Current Health Satisfaction in Prostate Cancer (CHS-PCa) were evaluated at baseline, as well as at weeks 12, 24, 48, and 72 after AA+P initiation. Descriptive analysis was used with continuous variables. Changes from baseline were summarized using mean (standard deviation [SD]). RESULTS: At a median age of 76.6 (8.94), baseline FACT-P total score was 111.3 (19.56) with no significant change in their functional status observed from baseline over time. The median baseline MoCA score was 25.2 (4.52), yet subsequent assessments showed an absence of cognitive decline while under treatment. Similarly, no meaningful changes were detected in BPI, BFI, and CHS-PCa during the 72-week study period, thus suggesting that patients' PROs were well-maintained throughout AA+P treatment. Prostate-specific antigen (PSA) response with >50% decline was 66.4%. Safety profile was consistent with the known side effect of AA+P. CONCLUSIONS: COSMiC represents the largest Canadian mCRPC cohort treated with AA+P with real-world, prospective evaluation of PROs. This data demonstrated the maintenance in quality of life and cognitive status over the course of the study and underscores the importance of PRO use in this complex patient population.

Canadian Update on Surgical Procedures (CUSP) Urology Group consensus for intraoperative hemostasis during minimally invasive partial nephrectomy.

INTRODUCTION: Partial nephrectomy remains the gold standard in the management of small renal masses. However, minimally invasive partial nephrectomy (MIPN) is associated with a steep learning curve, and optimal, standardized techniques for time-efficient hemostasis are poorly described. Given the relative lack of evidence, the goal was to describe a set of actionable guiding principles, through an expert working panel, for urologists to approach hemostasis without compromising warm ischemia or oncological outcomes. METHODS: A three-step modified Delphi method was used to achieve expert agreement on the best practices for hemostasis in MIPN. Panelists were recruited from the Canadian Update on Surgical Procedures (CUSP) Urology Group, which represent all provinces, academic and community practices, and fellowship-and non-fellowship-trained surgeons. Thirty-two (round 1) and 46 (round 2) panellists participated in survey questionnaires, and 22 attended the in-person consensus meeting. RESULTS: An initial literature search of 945 articles (230 abstracts) underwent screening and yielded 24 preliminary techniques. Through sequential survey assessment and in-person discussion, a total of 11 strategies were approved. These are temporally distributed prior to tumor resection (five principles), during tumor resection (two principles), and during renorrhaphy (four principles). CONCLUSIONS: Given the variability in tumor size, depth, location, and vascularity, coupled with limitations of laparoscopic equipment, achieving consistent hemostasis in MIPN may be challenging. Despite over two decades of MIPN experience, limited evidence exists to guide clinicians. Through a three-step Delphi method and rigorous iterative review with a panel of experts, we ascertained a guiding checklist of principles for newly beginning and practicing urologists to reference.

Upregulation of PACE4 in prostate cancer is not dependent on E2F transcription factors.

Recent studies in prostate cancer have identified PACE4, a proprotein convertase enzyme, as an emerging therapeutic target. Inhibition of PACE4-altCT, an oncogenic isoform of PACE4, using molecular or pharmacological approaches results in decreased cell proliferation and tumor progression in xenograft models. Although several validations have confirmed PACE4-altCT as a novel therapeutic target, the transcriptional regulation of PACE4 isoforms and mechanism of action remain a challenge. Previously, it has been reported that the human PACE4 promoter possesses potential binding sites for the E2F family of transcription factors, all of which are involved in cell cycle regulation and synthesis of DNA in mammalian cells. Therefore, we attempted to conduct in-depth evaluation of E2Fs on PACE4 and PACE4 isoform expression in prostate cancer. We conducted in vitro molecular silencing studies in various prostate cancer cell lines and determined the change in PACE4 expression levels. The results clearly show that the E2Fs alone do not alter PACE4 expression.

Best practices for enhancing surgical research: a perspective from the Canadian Association of Chairs of Surgical Research

Summary: The Canadian Association of Chairs of Surgical Research was created in 2014, with representation from every departmental surgical research committee across Canada, to establish Canadian surgical research as a beacon for health care innovation and to propose solutions for the daily challenges facing surgeon-researchers. Our key mandate has been to identify challenges for surgeons and scientists performing research to prevent further erosion of this vital area of activity that benefits patients, health care service providers and Canadian society. This article outlines the findings of a nationwide survey sent to all members of departments of surgery across Canada, seeking input on current threats and potential solutions. The results suggest that surgical research in Canada is experiencing a decline in funding and an increase in challenges affecting research productivity of academic surgeons, such as pressures to be clinically active, unpredictable surgical schedules, growing administrative demands, and increasing complexity of patient populations. Although surgeons are productive in their research endeavours, institutional changes and sharing of best practices are needed to ensure sustainable growth of research programs.

Apelin-13 Regulates Vasopressin-Induced Aquaporin-2 Expression and Trafficking in Kidney Collecting Duct Cells.

BACKGROUND/AIMS: Apelin and its G protein-coupled receptor APJ (gene symbol Aplnr) are strongly expressed in magnocellular vasopressinergic neurons suggesting that the apelin/APJ system plays a key role at the central level in regulating salt and water balance by counteracting the antiduretic action of vasopressin (AVP). Likewise, recent studies revealed that apelin exerts opposite effects to those of vasopressin induced on water reabsorption via a direct action on the kidney collecting duct. However, the underlying mechanisms of the peripheral action of apelin are not clearly understood. Here, we thus investigated the role of the apelin/APJ system in the regulation of water balance in the kidney, and more specifically its involvement in modulating the function of aquaporin-2 (AQP2) in the collecting duct. METHODS: Mouse cortical collecting duct cells (mpkCCD) were incubated in the presence of dDAVP and treated with or without apelin-13. Changes in AQP2 expression and localization were determined by immunoblotting and confocal immunofluorescence staining. RESULTS: Herein, we showed that the APJ was present in mpkCCD cells. Treatment of mpkCCD with apelin-13 reduced the cAMP production and antagonized the AVP-induced increase in AQP2 mRNA and protein expressions. Immunofluorescent experiments also revealed that the AVP-induced apical cell surface expression of AQP2, and notably its phosphorylated isoform AQP2-pS269, was considerably reduced following apelin-13 application to mpkCCD cells. CONCLUSION: Our data reinforce the aquaretic role of the apelin/APJ system in the fine regulation of body fluid homeostasis at the kidney level and its physiological opposite action to the antiduretic activity of AVP.

Effectiveness of fosfomycin tromethamine prophylaxis in preventing infection following transrectal ultrasound-guided prostate needle biopsy: Results from a large Canadian cohort.

OBJECTIVES: Rates of infection following transrectal ultrasound-guided prostate biopsy (TRUSPB) are increasing. The aim of this study was to evaluate the effectiveness of fosfomycin tromethamine (FMT) prophylaxis in preventing post-TRUSPB infectious complications. METHODS: This nested case-control study included patients undergoing TRUSPB in a Canadian tertiary-care hospital who developed post-TRUSPB bacteraemia or urinary tract infection. Four prophylaxis periods were defined: (i) ciprofloxacin, low-resistance period (CIPRO-LOW), 2002-2009; (ii) ciprofloxacin, high-resistance period (CIPRO-HIGH), 2010-October 2013; (iii) oral FMT, one dose (FOSFO1), December 2013-September 2015; and (iv) oral FMT, two doses (FOSFO2), November 2015-June 2016. Incidence rates of the infection were calculated. RESULTS: TRUSPB (n=9391) resulted in 138 cases of urinary sepsis (58% with bacteraemia). The incidence rates were 1.8% (CIPRO-HIGH), 3.5% (FOSFO1; P=0.004 vs. CIPRO-HIGH) and 2.7% (FOSFO2; P=0.19 vs. CIPRO-HIGH). Although Escherichia coli remained the predominant pathogen with fosfomycin-based regimens, the proportion of infections caused by Klebsiella spp. was higher (20/66; 30.3%) than with ciprofloxacin-based regimens (2/77; 2.6%; P<0.0001). CONCLUSION: Independent risk factors for infection were the prophylactic regimen administered, presence of urological co-morbidities and diabetes. FMT was therefore not an effective alternative to ciprofloxacin for preventing post-TRUSPB urinary sepsis. These results highlight the need for novel antibacterial prophylaxis approaches.

Kidney Cancer Research Network of Canada consensus statement on the role of adjuvant therapy after nephrectomy for high-risk, non-metastatic renal cell carcinoma: A comprehensive analysis of the literature and meta-analysis of randomized controlled trials.

INTRODUCTION: The Kidney Cancer Research Network of Canada (KCRNC) collaborated to prepare this consensus statement about the use of target agents as adjuvant therapy in patients with non-metastatic renal cell carcinoma (nmRCC) after nephrectomy. We reviewed the published data and performed a meta-analysis of studies that focused on vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs). METHODS: A systematic literature search identified seven trials on adjuvant target therapy in nmRCC. Three trials, the ASSURE, S-TRAC, and PROTECT, focused on VEGFR TKIs and represented the focus of the study, including a meta-analysis combining their data on disease-free survival (DFS) and overall survival (OS). RESULTS: The ASSURE trial showed no DFS or OS benefit of TKIs over placebo after one year of adjuvant sorafenib or sunitinib. In contrast, the S-TRAC trial showed improved DFS after one year of adjuvant sunitinib using central review process, but not using investigator review process. No OS benefit was recorded in either study. Recently, the PROTECT trial also showed no DFS or OS benefit when one year of adjuvant pazopanib was compared to placebo. Meta-analyses of the pooled DFS and OS estimates from all three trials resulted in DFS and OS hazard ratios of 0.87 (95% confidence interval [CI] 0.73-1.04) and 1.04 (95% CI 0.89-1.22), respectively. CONCLUSIONS: Data from three available clinical trials of adjuvant VEGFR TKIs vs. placebo do not currently support the use of adjuvant TKI therapy as standard of care after nephrectomy for nmRCC. At this time, adjuvant TKI-based adjuvant therapy is not recommended for routine use after nephrectomy for high-risk nmRCC, but highly motivated patients may benefit from a discussion with their oncologist regarding the risks and benefits of adjuvant TKI.

The impact of targeted therapy on healthcare resource use in patients with metastatic renal cell carcinoma: The University of Sherbrooke experience.

INTRODUCTION: We assessed the impact of targeted therapies on healthcare resource use and compared treatment regimens used in patients diagnosed with metastatic renal cell carcinoma (mRCC). METHODS: Clinicopathological and administrative data of patients with mRCC from our institution were retrospectively collected from January 2000 to August 2014. Patients were divided into two groups based on the use of targeted therapies. Healthcare resource use (HCRU) data included non-scheduled total number of hospitalizations, total days hospitalized, emergency department visits, and healthcare professional consultations. Each variable was presented with absolute and relative values (i.e., per month of survival). Statistics relied on the use of t-student and Chi-square tests. RESULTS: Ninety-nine patients were included in the study; 60 were treated with targeted therapy. There were no statistically significant differences between the two groups for demographic features and clinicopathological stage. HCRU analysis revealed an absolute increase in the median number of healthcare consultants (6 vs. 4; p<0.01) and emergency department visits (1 vs. 0; p=0.02) for the targeted therapy group. However, analysis per month of survival showed the targeted therapy group had fewer consultants (0.33 vs. 0.40; p=0.04) and hospitalizations (0.09 vs. 0.13; p=0.03) than their counterpart. Population size, non-randomization, treatment selection bias, and heterogeneity were the main limitations of this study. CONCLUSIONS: Monthly use of HCRU is lower in mRCC patients treated with targeted therapies. However, because of a greater overall survival, their absolute total HCRU will be higher than those not exposed to targeted agents.

NLS-Cholic Acid Conjugation to IL-5Rα-Specific Antibody Improves Cellular Accumulation and In Vivo Tumor-Targeting Properties in a Bladder Cancer Model.

Receptor-mediated internalization followed by trafficking and degradation of antibody-conjugates (ACs) via the endosomal-lysosomal pathway is the major mechanism for delivering molecular payloads inside target tumor cells. Although a mainstay for delivering payloads with clinically approved ACs in cancer treatment and imaging, tumor cells are often able to decrease intracellular payload concentrations and thereby reduce the effectiveness of the desired application. Thus, increasing payload intracellular accumulation has become a focus of attention for designing next-generation ACs. We developed a composite compound (ChAcNLS) that enables ACs to escape endosome entrapment and route to the nucleus resulting in the increased intracellular accumulation as an interleukin-5 receptor α-subunit (IL-5Rα)-targeted agent for muscle invasive bladder cancer (MIBC). We constructed 64Cu-A14-ChAcNLS, 64Cu-A14-NLS, and 64Cu-A14 and evaluated their performance by employing mechanistic studies for endosome escape coupled to nuclear routing and determining whether this delivery system results in improved 64Cu cellular accumulation. ACs consisting of ∼20 ChAcNLS or NLS moieties per 64Cu-A14 were prepared in good yield, high monomer content, and maintaining high affinity for IL-5Rα. Confocal microscopy analysis demonstrated ChAcNLS mediated efficient endosome escape and nuclear localization. 64Cu-A14-ChAcNLS increased 64Cu cellular accumulation in HT-1376 and HT-B9 cells relative to 64Cu-A14 and 64Cu-A14-NLS. In addition, we tested 64Cu-A14-ChAcNLS in vivo to evaluate its tissue distribution properties and, ultimately, tumor uptake and targeting. A model of human IL-5Rα MIBC was developed by implanting NOD/SCID mice with subcutaneous HT-1376 or HT-B9MIBC tumors, which grow containing high and low IL-5Rα-positive tumor cell densities, respectively. ACs were intravenously injected, and daily blood sampling, biodistribution at 48 and 96 h, and positron emission tomography (PET) at 24 and 48 h were performed. Region of interest (ROI) analysis was also performed on reconstructed PET images. Pharmacokinetic analysis and biodistribution studies showed that 64Cu-A14-ChAcNLS had faster clearance rates from the blood and healthy organs relative to 64Cu-A14. However, 64Cu-A14-ChAcNLS maintained comparable tumor accumulation relative to 64Cu-A14. This resulted in 64Cu-A14-ChAcNLS having superior tumor/normal tissue ratios at both 48 and 96 h biodistribution time points. Visualization of AC distribution by PET and ROI analysis confirmed that 64Cu-A14-ChAcNLS had improved targeting of MIBC tumor relative to 64Cu-A14. In addition, 64Cu-A14 modified with only NLS had poor tumor targeting. This was a result of poor tumor uptake due to extremely rapid clearance. Thus, the overall findings in this model of human IL-5Rα-positive MIBC describe an endosome escape-nuclear localization cholic-acid-linked peptide that substantially enhances AC cellular accumulation and tumor targeting.

Metastatic renal cell carcinoma initially presenting with hematochezia and subsequently with vaginal bleeding: a case report.

BACKGROUND: We report an unusual case of a synchronous rectal and metachronous vaginal metastatic renal cell carcinoma. CASE PRESENTATION: A 78-year-old woman presented with hematochezia and a colonoscopy revealed a metastatic clear-cell renal cell carcinoma rectal polyp biopsy-proven. Abdominal computed tomography identified a 9.0-cm left renal mass with renal vein thrombosis, for which she underwent a laparoscopic radical nephrectomy. Histopathological examination confirmed a pT3a clear-cell renal cell carcinoma. Seven months later, the patient presented with vaginal bleeding. Physical examination revealed a vaginal polypoid mass and biopsy confirmed a clear-cell renal cell carcinoma metastasis. CONCLUSIONS: This case represents unusual manifestations of metastatic renal cell carcinoma and is a reminder of the wide spectrum of clinical course of this disease.

Targeting IL-5Rα with antibody-conjugates reveals a strategy for imaging and therapy for invasive bladder cancer.

Despite the high interest and concern due to an increasing incidence and death rate, patients who develop muscle invasive bladder cancer (MIBC) have few options available. However, the past decade has produced many candidate bladder tumor-specific markers but further development of these markers is still needed for creating effective targeted medications to solve this urgent need. Interleukin-5 receptor α-subunit (IL-5Rα) has recently been reported to be involved in MIBC progression. Thus, we aimed to validate IL-5Rα as a target for antibody-conjugates to better manage patients with MIBC. Patients were recruited and their tumors were processed for IL-5Rα immunohistochemical analysis. NOD/SCID mice were also heterotopically implanted with the human MIBC HT-1376 and HT-B9 cell lines and established xenografts immunohistochemically evaluated for IL-5Rα and compared against patient tumors. Using the mAb A14, an antibody-drug conjugate (ADC) and a radiolabeled immunoconjugate (RIC) were developed by conjugating to vinblastine and to the positron emitter copper-64 (64Cu), respectively. As a proof-of-concept for ADC and RIC efficacy, in vitro cytotoxicity and in vivo positron emission tomography (PET) imaging in tumor-bearing mice were performed, respectively. In addition, as rapid internalization and accumulation are important components for effective antibody-conjugates, we evaluated these aspects in response to IL-5 and 64Cu-A14 treatments. Our findings suggest that although IL-5Rα protein expression is preferentially increased in MIBC, it is rapid IL-5Rα-mediated internalization allowing vinblastine-A14 to have cytotoxic activity and 64Cu-A14 to detect MIBC tumors in vivo. This is the first report to elucidate the potential of IL-5Rα as an attractive MIBC target for antibody-conjugate applications.

PACE4 Undergoes an Oncogenic Alternative Splicing Switch in Cancer.

Inhibition of PACE4, a proprotein convertase that is overexpressed in prostate cancer, has been shown to block cancer progression in an androgen-independent manner. However, the basis for its overexpression and its growth-inhibitory effects are mitigated and uncertain. Here, we report that PACE4 pre-mRNA undergoes DNA methylation-sensitive alternative splicing of its terminal exon 3' untranslated region, generating an oncogenic, C-terminally modified isoform (PACE4-altCT). We found this isoform to be strongly expressed in prostate cancer cells, where it displayed an enhanced autoactivating process and a distinct intracellular routing that prevented its extracellular secretion. Together, these events led to a dramatic increase in processing of the progrowth differentiation factor pro-GDF15 as the first PACE4 substrate to be identified in prostate cancer. We detected robust expression of PACE4-altCT in other cancer types, suggesting that an oncogenic switch for this proenzyme may offer a therapeutic target not only in advanced prostate cancer but perhaps also more broadly in human cancer. Cancer Res; 77(24); 6863-79. ©2017 AACR.

Transperitoneal laparoscopic nephrectomy: Assessing complication risk in cases of previous abdominal surgery.

INTRODUCTION: We aimed to assess the effect of previous abdominal surgery on perioperative outcomes in patients undergoing transperitoneal laparoscopic partial (LPN) or radical (LRN) nephrectomy for renal masses. METHODS: We retrospectively reviewed all cases of LPN and LRN for renal masses at our institution between 2008 and 2014. Patients were divided in two groups, those with and without prior abdominal surgery. Four perioperative outcomes were compared, namely, operative time (OT), estimated blood loss (EBL), length of stay (LOS), and 30-days complications rate. A subanalysis was performed to address the impact of previous open cholecystectomy on right LPN or LRN. RESULTS: Of 293 patients identified, 146 (49.8%) had previous abdominal surgery. In univariate analysis, no differences in operative time (136 vs. 144 minutes; p=0.154), EBL (88 vs. 100 mL; p=0.211), or 30-day complication rate (24 vs. 14%; p=0.069) were recorded between the groups. Only LOS favoured patients without previous abdominal surgery (3 vs. 4 days; p=0.001). In multivariate analysis, prior abdominal surgery was not associated with an increased OT, EBL, LOS, or complication rate. The analysis of right nephrectomies showed increased OT (148 vs. 128 minutes; p=0.049) and complication rate (42 vs. 16%; p=0.004) for patients with past open cholecystectomy compared to those without. Multivariate analysis revealed that prior open cholecystectomy was associated with a longer LOS (ORmedian=2.7 [1.2-8.0]) and an increased risk of complications (ORmedian=4.5 [1.6-10.5]). CONCLUSIONS: In this cohort, previous abdominal surgery was not associated with worse perioperative outcomes after transperitoneal LPN and LRN for renal masses. However, previous open cholecystectomy resulted in a higher risk of complication and a longer LOS in patients undergoing right laparoscopic nephrectomy.