Targeting prostate cancer with Clostridium perfringens enterotoxin functionalized nanoparticles co-encapsulating imaging cargo enhances magnetic resonance imaging specificity.

Magnetic resonance is a key imaging tool for the detection of prostate cancer; however, better tools focusing on cancer specificity are required to distinguish benign from cancerous regions. We found higher expression of claudin-3 (CLDN-3) and -4 (CLDN-4) in higher grade than lower-grade human prostate cancer biopsies (n = 174), leading to the design of functionalized nanoparticles (NPs) with a non-toxic truncated version of the natural ligand Clostridium perfringens enterotoxin (C-CPE) that has a strong binding affinity to Cldn-3 and Cldn-4 receptors. We developed a first-of-its-type, C-CPE-NP-based MRI detection tool in a prostate tumor-bearing mouse model. NPs with an average diameter of 152.9 ±â€¯15.7 nm (RS1) had a 2-fold enhancement of tumor specificity compared to larger (421.2 ±â€¯33.8 nm) NPs (RS4). There was a 1.8-fold (P < 0.01) and 1.6-fold (P < 0.01) upregulation of the tumor-to-liver signal intensities of C-RS1 and C-RS4 (functionalized NPs) compared to controls, respectively. Also, tumor specificity was 3.1-fold higher (P < 0.001) when comparing C-RS1 to C-RS4. This detection tool improved tumor localization of contrast-enhanced MRI, supporting potential clinical applicability.

The Prognostic Association of Prostate MRI PI-RADS™ v2 Assessment Category and Risk of Biochemical Recurrence after Definitive Local Therapy for Prostate Cancer: A Systematic Review and Meta-Analysis.

PURPOSE: Although the Prostate Imaging-Reporting and Data System™ version 2 (PI-RADS™ v2) is a reliable diagnostic tool for significant prostate cancer, less is known about the prognostic significance of the structured reporting scheme for estimating oncologic outcomes after treatment. We aimed to synthesize the available evidence regarding the association of PI-RADS v2 score and risk of biochemical recurrence (BCR) among patients undergoing primary definitive treatment for prostate cancer. MATERIALS AND METHODS: We systematically queried the PubMed® and Web of Science™ databases to identify studies addressing the association between the PI-RADS v2 and treatment outcomes. We included studies through November 2020 that assessed the independent prognostic significance of PI-RADS v2. After assessing risk of bias and quality, we conducted a formal meta-analysis to estimate the pooled effects of prostate magnetic resonance imaging (MRI) classification on the risk of BCR. RESULTS: We identified 9 and 7 eligible studies including 2,274 and 1,215 patients for the systematic review and meta-analysis, respectively. Eight were conducted in the context of radical prostatectomy and 1 post-radiation. Among patients treated with radical prostatectomy, higher PI-RADS v2 scores were significantly associated with risk of BCR (pooled HR 3.06, 95% CI 2.16-4.33; p <0.01). There was no significant heterogeneity among studies. For all studies, PI-RADS v2 score remained significantly associated with BCR (pooled HR 3.19, 95% CI 2.28-4.45; p <0.01). CONCLUSIONS: Prostate MRI findings assessed with the PI-RADS v2 classification were independently associated with risk of BCR after definitive local therapy, primarily based on data from radical prostatectomy. These findings support the prognostic significance of MRI, in addition to its role in prostate cancer diagnosis.

Protective effect of hydroxyfasudil, a Rho kinase inhibitor, on ventral prostatic hyperplasia in the spontaneously hypertensive rat.

BACKGROUND: Rho kinase (ROCK) pathway is associated with various cellular functions, such as smooth muscle contraction, inflammatory response, and cell proliferation. The spontaneously hypertensive rat (SHR) is commonly used genetically hypertensive rat model which develops hyperplastic morphological abnormalities in the ventral prostate. We investigated whether administration of hydroxyfasudil, a ROCK inhibitor, could reduce the levels of growth factors, inflammatory markers, and morphological abnormalities in the ventral prostate of the SHR. METHODS: Twelve-week-old SHRs were treated with hydroxyfasudil (1 mg/kg/day, i.p.) or vehicle once daily for another 6 weeks. Wistar Kyoto (WKY) rats treated with vehicle were used as normotensive controls. At 18 weeks of age, blood pressure and heart rate were measured by the tail cuff method. Then the rats were sacrificed, and the ventral prostates were removed. The levels of ROCK activity, growth factors (TGF-ß1 and bFGF), a smooth muscle differentiation marker (α-SMA) and an inflammatory cytokine (IL-6) in the ventral prostate were measured by ELISA and western blot. A histological evaluation in each group was also performed. RESULTS: There were significant increases in blood pressure, prostate weight, prostate body weight ratio, and tissue levels of ROCK activity, TGF-ß1, bFGF, α-SMA, and IL-6 in the SHR compared to the WKY rat. Histological examination of the ventral prostate showed morphological abnormalities such as a higher degree of proliferation in the glandular epithelial and stromal area in the SHR compared to the WKY rat. Treatment with hydroxyfasudil reduced the elevated ROCK activity, TGF-ß1, bFGF, α-SMA, and IL-6 found in the ventral prostate of the SHR. Moreover, treatment with hydroxyfasudil decreased the morphological abnormalies in the SHR ventral prostate. CONCLUSIONS: Treatment with hydroxyfasudil decreased the growth factors, an inflammatory cytokine, and morphological abnormalies in the SHR ventral prostate. These results suggest that chronic treatment with hydroxyfasudil may inhibit the progression of prostatic hyperplasia in the SHR.

Olmesartan ameliorates urinary dysfunction in the spontaneously hypertensive rat via recovering bladder blood flow and decreasing oxidative stress.

PURPOSE: As hypertension (HT) is one of the risk factors for lower urinary tract symptoms, we investigated the effect of an angiotensin II type I receptor blocker, olmesartan, on bladder dysfunction in the spontaneously hypertensive rat (SHR). MATERIALS AND METHODS: Twelve-week-old male SHRs were administered perorally with olmesartan (0, 1, or 3 mg/kg/day) or nifedipine (30 mg/kg/day) for 6 weeks. Wistar rats were used as normotensive controls. The effects of olmesartan or nifedipine on blood pressure (BP), bladder blood flow (BBF), urodynamic parameters, tissue levels of malondialdehyde (MDA), nuclear factor erythroid 2-related factor 2 (Nrf2), and nerve growth factor (NGF) were measured in the bladder. Localization of 4-hydroxy-2-nonenal (4-HNE), Nrf2, and NGF in the bladder was shown by immunohistochemistry. RESULTS: The SHRs showed significant increase in BP, micturition frequency, and expression of MDA, 4-HNE, Nrf2, and NGF when compared to the control Wistar rats. Conversely, there was a decrease in BBF and single voided volume in SHRs when compared to Wistar rats. Treatment with olmesartan and nifedipine significantly improved BP. However, only olmesartan significantly ameliorated urodynamic parameters and oxidative damage compared to the non-treated SHR. The immunoreactivities of 4-HNE, Nrf2, and NGF in SHR urothelium and blood vessels were increased compared to the control. Treatment with a high dose of olmesartan decreased the expressions of 4-HNE, Nrf2, and NGF in the bladder. CONCLUSION: Our data suggest that BP, BBF, and oxidative stress may be responsible for the functional changes in HT-related bladder dysfunction. Olmesartan significantly ameliorated this bladder dysfunction.

Development of a Longitudinal Prostate Cancer Transcriptomic and Clinical Data Linkage.

Importance: Although tissue-based gene expression testing has become widely used for prostate cancer risk stratification, its prognostic performance in the setting of clinical care is not well understood. Objective: To develop a linkage between a prostate genomic classifier (GC) and clinical data across payers and sites of care in the US. Design, Setting, and Participants: In this cohort study, clinical and transcriptomic data from clinical use of a prostate GC between 2016 and 2022 were linked with data aggregated from insurance claims, pharmacy records, and electronic health record (EHR) data. Participants were anonymously linked between datasets by deterministic methods through a deidentification engine using encrypted tokens. Algorithms were developed and refined for identifying prostate cancer diagnoses, treatment timing, and clinical outcomes using diagnosis codes, Common Procedural Terminology codes, pharmacy codes, Systematized Medical Nomenclature for Medicine clinical terms, and unstructured text in the EHR. Data analysis was performed from January 2023 to January 2024. Exposure: Diagnosis of prostate cancer. Main Outcomes and Measures: The primary outcomes were biochemical recurrence and development of prostate cancer metastases after diagnosis or radical prostatectomy (RP). The sensitivity of the linkage and identification algorithms for clinical and administrative data were calculated relative to clinical and pathological information obtained during the GC testing process as the reference standard. Results: A total of 92 976 of 95 578 (97.2%) participants who underwent prostate GC testing were successfully linked to administrative and clinical data, including 53 871 who underwent biopsy testing and 39 105 who underwent RP testing. The median (IQR) age at GC testing was 66.4 (61.0-71.0) years. The sensitivity of the EHR linkage data for prostate cancer diagnoses was 85.0% (95% CI, 84.7%-85.2%), including 80.8% (95% CI, 80.4%-81.1%) for biopsy-tested participants and 90.8% (95% CI, 90.5%-91.0%) for RP-tested participants. Year of treatment was concordant in 97.9% (95% CI, 97.7%-98.1%) of those undergoing GC testing at RP, and 86.0% (95% CI, 85.6%-86.4%) among participants undergoing biopsy testing. The sensitivity of the linkage was 48.6% (95% CI, 48.1%-49.1%) for identifying RP and 50.1% (95% CI, 49.7%-50.5%) for identifying prostate biopsy. Conclusions and Relevance: This study established a national-scale linkage of transcriptomic and longitudinal clinical data yielding high accuracy for identifying key clinical junctures, including diagnosis, treatment, and early cancer outcome. This resource can be leveraged to enhance understandings of disease biology, patterns of care, and treatment effectiveness.

Nanoparticles for urothelium penetration and delivery of the histone deacetylase inhibitor belinostat for treatment of bladder cancer.

Nearly 40% of patients with non-invasive bladder cancer will progress to invasive disease despite locally-directed therapy. Overcoming the bladder permeability barrier (BPB) is a challenge for intravesical drug delivery. Using the fluorophore coumarin (C6), we synthesized C6-loaded poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs), which were surface modified with a novel cell penetrating polymer, poly(guanidinium oxanorbornene) (PGON). Addition of PGON to the NP surface improved tissue penetration by 10-fold in intravesically-treated mouse bladder and ex vivo human ureter. In addition, NP-C6-PGON significantly enhanced intracellular uptake of NPs compared to NPs without PGON. To examine biological activity, we synthesized NPs that were loaded with the histone deacetylase (HDAC) inhibitor belinostat (NP-Bel-PGON). NP-Bel-PGON exhibited a significantly lower IC50 in cultured bladder cancer cells, and sustained hyperacetylation, when compared to unencapsulated belinostat. Xenograft tumors treated with NP-Bel-PGON showed a 70% reduction in volume, and a 2.5-fold higher intratumoral acetyl-H4, when compared to tumors treated with unloaded NP-PGON. FROM THE CLINICAL EDITOR: These authors demonstrate that PLGA nanoparticles with PGON surface functionalization result in greatly enhanced cell penetrating capabilities, and present convincing data from a mouse model of bladder cancer for increased chemotherapy efficacy.

Functionalized nanoparticles targeting biomarkers for prostate cancer imaging and therapy.

Nanomedicine is an evolving field of scientific research with unique advantages and challenges for the detection and treatment of medical diseases. Since 1995, the FDA has approved the administration of nanoparticle-based therapies. The initial generation of nanoparticles relied on an enhanced permeability and retention effect, associated with an increased penetrability of tumor related blood vessels. With increasing knowledge of biomarkers and molecular targets, active targeting of circulating tumor cells by nanoparticles provides an exciting area for application. The selective targeting of prostate cancer cells using a nanotechnology-based mechanism has the potential to optimize the delivery of therapeutic payloads directly to prostate cancer cells while minimizing systemic toxicities. The molecular targets that have been studied include prostate specific membrane antigen, gastrin-releasing peptide protein, glucose related protein, CD44, claudin, C-X-C chemokine receptor type 4 (CXCR-4), and adenosine. The clinical potential for nanoparticle-based therapies is supported by several studies that have progressed past the preclinical stage into clinical trials. In this review, we present the molecular biomarkers that have been targeted by ligands conjugated to the surface of nanoparticles for prostate cancer imaging and therapy.

Knocking down claudin receptors leads to a decrease in prostate cancer cell migration, cell growth, cell viability and clonogenic cell survival.

Prostate cancer is the most common solid organ malignancy in the United States, and has the highest probability of all cancers in becoming invasive. New molecular targets are needed to define and impede the growth and progression of advanced prostate cancers. Claudins (Cldns) are transmembrane proteins that regulate paracellular permeability and cell polarity, and their levels are elevated in many human cancers such as breast, ovarian, pancreatic, and prostatic cancers. Previously, we found that Cldn3 and Cldn4 are expressed in aggressive high-grade human prostate cancer specimens. We and others have shown that there are higher levels of Cldn3 and Cldn4 in metastatic human prostate cancer cells than in normal human prostate cells. The result of targeting Cldn3 and Cldn4 expression on the growth and viability of prostate cancer cells has not been elucidated. Human prostate cancer PC3 and LNCaP cells were transfected with Cldn3 or -4 small interfering RNAs (siRNAs). Cldn3/Cldn4 siRNA treatment resulted in a greater than 85% decrease in the protein levels of Cldn3 and Cldn4, which was accompanied by a 30-40% decrease in prostate cancer cell growth and a 60-65% reduction in cell viability. There was decreased cell migration with Cldn3 and Cldn4 siRNA in both PC3 and LNCaP cells and a 60-75% decrease in the number of clones when treated with siCldn3 or siCldn4 compared to control. Knocking down Cldn3/Cldn4 affects prostate cancer cell growth and survival and may have therapeutic implications.

Down-regulation of GP130 signaling sensitizes bladder cancer to cisplatin by impairing Ku70 DNA repair signaling and promoting apoptosis.

Chemoresistance is one of the barriers for the development of bladder cancer treatments. Previously, we showed that glycoprotein-130 (GP130) is overexpressed in chemoresistant bladder cancer cells and that knocking down GP130 expression reduced cell viability. In our current work, we showed that down-regulation of GP130 sensitized bladder cancer cells to cisplatin-based chemotherapy by activating DNA repair signaling. We performed immunohistochemistry and demonstrated a positive correlation between the levels of Ku70, an initiator of canonical non-homologous end joining repair (c-NHEJ) and suppressor of apoptosis, and GP130 in human bladder cancer specimens. GP130 knockdown by SC144, a small molecule inhibitor, in combination with cisplatin, increased the number of DNA lesions, specifically DNA double-stranded breaks, with a subsequent increase in apoptosis and reduced cell viability. Furthermore, GP130 inhibition attenuated Ku70 expression in bladder and breast cancer cells as well as in transformed kidney cells. In addition, we fabricated a novel polymer-lipid hybrid delivery system to facilitate GP130 siRNA delivery that had a similar efficiency when compared with Lipofectamine, but induced less toxicity.

Initial Evaluation of Rapid, Direct-to-Digital Prostate Biopsy Pathology.

CONTEXT.­: Pathologist interobserver discordance is significant in grading of prostate cancer, limiting reliability. Diagnostic reproducibility may be improved with digital images, but adoption faces workflow, cost, and quality challenges. A novel digital method using an alternative tissue processing approach and novel laser microscopy system potentially addresses these issues. OBJECTIVE.­: To evaluate the capability of this new method for primary diagnostic interpretation in clinical prostate biopsy specimens. DESIGN.­: Forty patients with a high likelihood of prostate cancer based on magnetic resonance imaging consented to investigational core biopsy. A subset of samples was used for direct comparison of physical slide preparation effects and time-tracking determination with multiphoton microscopy. Twenty samples were processed for diagnostic comparison between multilevel digital slides and subsequently produced physical slides. A reference diagnosis based on all data was established using grade groups. Level of diagnostic match and requests for immunohistochemistry were compared between physical and digital diagnoses. Immunohistochemical staining and length measurements were secondary outcomes. RESULTS.­: Interpretations based on direct multiphoton imaging yielded diagnoses that were at least as accurate as standard histology; cancer diagnosis correlation was 89% (51 of 57) by physical slides and 95% (53 of 56) by multiphoton microscopy. Grade-level concordance was 73% (44 of 60) by either method. Immunohistochemistry for routine prostate cancer-associated markers on these alternatively processed tissues was unaffected. Alternatively processed tissues resulted in longer measured core and cancer lengths, suggestive of improved orientation and visualization. CONCLUSIONS.­: Findings support high potential for complete interpretation of prostate core biopsies using solely multiphoton microscopy of intact specimens, with potential diagnostic benefits as well as reduced processing time and reduced processing complexity.

Genome-wide association analysis reveals regulation of at-risk loci by DNA methylation in prostate cancer.

Epigenetic changes are potentially important for the ontogeny and progression of tumors but are not usually studied because of the complexity of analyzing transcript regulation resulting from epigenetic alterations. Prostate cancer (PCa) is characterized by variable clinical manifestations and frequently unpredictable outcomes. We performed an expression quantitative trait loci (eQTL) analysis to identify the genomic regions that regulate gene expression in PCa and identified a relationship between DNA methylation and clinical information. Using multi-level information published in The Cancer Genome Atlas, we performed eQTL-based analyses on DNA methylation and gene expression. To better interpret these data, we correlated loci and clinical indexes to identify the important loci for both PCa development and progression. Our data demonstrated that although only a small proportion of genes are regulated via DNA methylation in PCa, these genes are enriched in important cancer-related groups. In addition, single nucleotide polymorphism analysis identified the locations of CpG sites and genes within at-risk loci, including the 19q13.2-q13.43 and 16q22.2-q23.1 loci. Further, an epigenetic association study of clinical indexes detected risk loci and pyrosequencing for site validation. Although DNA methylation-regulated genes across PCa samples are a small proportion, the associated genes play important roles in PCa carcinogenesis.

Achieving highly efficient gene transfer to the bladder by increasing the molecular weight of polymer-based nanoparticles.

Short dwell-time and poor penetration of the bladder permeability barrier (BPB) are the main obstacles to intravesical treatments for bladder diseases, and is evidenced by the lack of such therapeutic options on the market. Herein, we demonstrate that by finely tuning the molecular weight of our cationic polymer mucoadhesive nanoparticles, we enhanced our gene transfer, leading to improved adherence and penetrance through the BPB in a safe and efficient manner. Specifically, increasing the polymer molecular weight from 45 kDa to 83 kDa enhanced luciferase plasmid transfer to the healthy murine bladder, leading to 1.35 ng/g luciferase protein expression in the urothelium and lamina propria regions. The relatively higher molecular weight polymer (83 kDa) did not induce morphologic changes or inflammatory responses in the bladder. This approach of altering polymer molecular weight for prolonging gene transfer residence time and deeper penetration through the BPB could be the basis for the design of future gene therapies for bladder diseases.

Doubling of Decipher Biopsy Genomic Score Is Related to Disease Reclassification on Subsequent Surveillance Biopsy but Not Adverse Features on Radical Prostatectomy.

The utility of serial Decipher biopsy scores in a true active surveillance population is still unknown. In a man on active surveillance for low-risk prostate cancer, a doubling of the Decipher biopsy score within genomic low-risk category from first to the second biopsy related to biopsy reclassification to Gleason grade group 4 on the third biopsy. However, the final pathology at radical prostatectomy showed Gleason grade group 2 with an organ-confined disease. This case suggests that the genomic risk category of Decipher biopsy scores during active surveillance may be more informative than either the interval genomic score change or the biopsy Gleason grade group.

Synergistic inhibition of GP130 and ERK signaling blocks chemoresistant bladder cancer cell growth.

Multidrug resistance is a major treatment obstacle for recurrent and metastatic bladder cancer, which often leads to disease progression and poor clinical outcome. Although overexpression of interleukin-6 (IL-6) appears to play a critical role in the development of chemotherapy resistance, inhibitors for IL-6 alone have not improved clinical outcomes. Since the IL-6/IL-6R/GP130 complex is involved in multidrug resistance, another strategy would be to focus on glycoprotein-130 (GP130) since it dimerizes with IL-6R/CD26 as a membrane-bound signaling transducer receptor and initiates subsequent signaling activation and may be a potential therapeutic target. Currently, the role of GP130 in chemoresistant bladder cancer is unknown. In the present study, we demonstrate that GP130 is over-expressed in cisplatin and gemcitabine-resistant bladder cancer cells, and that the inhibition of GP130 expression significantly reduces cell viability, survival and migration. Downstream of GP130 is PI3K/AKT/mTOR signaling, which is inactivated by SC144, a GP130 inhibitor. However, Raf/MEK/ERK signaling, which also is downstream of GP130 is activated by SC144. This activation is likely based on a mTOR/S6K1/PI3K/ERK negative feedback loop, which is presumed to counteract the inhibitory effect of SC144 on tumor aggressiveness. Blocking both GP130 and pERK resulted in synergistic inhibition of cytotoxicity, clonal survival rates and cell migration in our chemotherapy resistant bladder cancer cells. This vertical inhibition offers a novel therapeutic strategy for targeting human chemoresistant bladder cancer.

Prostate Cancer Genomic Classifier Relates More Strongly to Gleason Grade Group Than Prostate Imaging Reporting and Data System Score in Multiparametric Prostate Magnetic Resonance Imaging-ultrasound Fusion Targeted Biopsies.

OBJECTIVE: To assess the association between Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) score, the Decipher score, and histologic grade of carcinoma in biopsy tissue among low- to intermediate-risk prostate cancer patients. METHODS: MRI-ultrasound targeted biopsy of regions of interest and concurrent 12-core systematic biopsy was performed on men with Gleason grade group (GG) 1 and 2. We compared Decipher score with PI-RADS scores and biopsy Gleason GG. Subgroup analyses were performed to evaluate patients who underwent radical prostatectomy (RP), and men with Decipher testing from a targeted biopsy core. RESULTS: One hundred two patients with GG1 and GG2 had biopsy Decipher testing. There was no significant difference in the median Decipher scores among the 3 multiparametric magnetic resonance imaging categories. Patients with GG2 vs GG1 in the setting of PI-RADS 4-5 had higher genomic scores (P = .01), but no significant difference was noted in patients with PI-RADS ≤3. The rate of genomic higher-risk disease on a targeted biopsy from PI-RADS5 was higher in GG2 (75%) vs GG1 (11.1%; P = .01). On multivariable logistic regression analysis, the Decipher score ≥0.45, (odds ratio (OR) 2.71; P = .02), and age (OR 1.11; P = .004) remained significant factors associated with Gleason GG2 on biopsy. CONCLUSION: High-risk genomic classification can be seen across all combinations of PI-RADS categories and Gleason GG1 and GG2, confirming a potential utility for Decipher testing in men with low- to favorable intermediate-risk prostate cancer. The Decipher biopsy genomic test related to Gleason GG independent of PI-RADSv2 score. Confirmatory genomic testing for patients undergoing active surveillance appears more valuable than PI-RADSv2 score.

Glycoprotein-130 Expression Is Associated with Aggressive Bladder Cancer and Is a Potential Therapeutic Target.

Predicting bladder cancer progression is important in selecting the optimal treatment for bladder cancer. Because current diagnostic factors regarding progression are lacking, new factors are needed to further stratify the curative potential of bladder cancer. Glycoprotein-130 (GP130), a transmembrane protein, is central to a number of signal transduction pathways involved in tumor aggressiveness, making it an attractive target. We hypothesize that if GP130 is found in an aggressive population of bladder tumors, then blocking GP130 expression may inhibit bladder cancer growth. Herein, we quantitatively show, using 11 patient samples and four bladder cancer cell lines, that GP130 is expressed in the aggressive human bladder tumors and in high-grade bladder cancer cell lines. Moreover, GP130 is significantly correlated with tumor grade, node category, tumor category, and patient outcome. We demonstrated a tumor-specific GP130 effect by blocking GP130 expression in bladder tumor cells, which resulted in decreased cell viability and reduced cell migration. Furthermore, we reduced tumor volume by approximately 70% compared with controls by downregulating GP130 expression using chitosan-functionalized nanoparticles encapsulating GP130 siRNA in an in vivo bladder cancer xenograft mouse model. Our results indicate that GP130 expression is linked to the aggressiveness of bladder tumors, and blocking GP130 has therapeutic potential in controlling tumor growth.

Tubedown expression correlates with the differentiation status and aggressiveness of neuroblastic tumors.

PURPOSE: The discovery and validation of new prognostic factors and further refinement of risk group stratification are needed to improve clinical interpretation of neuroblastoma. Our laboratory isolated and characterized a developmentally regulated gene named TUBEDOWN against which we have raised a monoclonal antibody (OE5). Tubedown becomes down-regulated postnatally yet remains strongly expressed in some neuroblastomas. The purpose of this study is to define the utility of Tubedown expression as a new measure of the differentiation status and aggressiveness of neuroblastic tumors. EXPERIMENTAL DESIGN: Tubedown protein expression was quantitatively assessed in neuroblastic tumors (neuroblastomas, ganglioneuroblastomas, and ganglioneuromas) and normal adrenal tissues using Western blot and OE5 immunohistochemistry. Regulation of Tubedown expression during retinoic acid-induced neuronal differentiation in neuroblastoma cell lines was assessed by Western blotting. RESULTS: High levels of Tubedown expression are observed in tumors with significant neuroblastic component, unfavorable histopathology, advanced stage, high-risk group, and poor outcome. In contrast, more differentiated subsets of neuroblastic tumors, ganglioneuroblastomas with favorable histopathology and ganglioneuromas, express low levels of Tubedown. In vitro, marked retinoic acid-induced neuronal differentiation responses of neuroblastoma cells are associated with a significant decrease in Tubedown expression, whereas limited neuronal differentiation responses to retinoic acid were associated with little or no decrease in Tubedown expression. CONCLUSIONS: Our results indicate that the levels of Tubedown expression are linked to the differentiation status and aggressiveness of neuroblastic tumors and represent an independent prognostic factor for neuroblastoma. Tubedown expression may be useful to more accurately define different neuroblastic tumor subsets and ultimately provide more adequate assessment and treatment for neuroblastoma patients.

Effect of Silodosin, an Alpha1A-Adrenoceptor Antagonist, on Ventral Prostatic Hyperplasia in the Spontaneously Hypertensive Rat.

BACKGROUND: A decreased prostatic blood flow could be one of the risk factors for benign prostatic hyperplasia/benign prostatic enlargement. The spontaneously hypertensive rat (SHR) shows a chronic prostatic ischemia and hyperplastic morphological abnormalities in the ventral prostate. The effect of silodosin, a selective alpha1A-adrenoceptor antagonist, was investigated in the SHR prostate as a prostatic hyperplasia model focusing on prostatic blood flow. METHODS: Twelve-week-old male SHRs were administered perorally with silodosin (100 µg/kg/day) or vehicle once daily for 6 weeks. Wistar Kyoto (WKY) rats were used as normotensive controls and were treated with the vehicle. The effect of silodosin on blood pressure and prostatic blood flow were estimated and then the prostates were removed and weighed. The tissue levels of malondialdehyde (MDA), interleukin-6 (IL-6), chemokine (C-X-C motif) ligand 1/cytokine-induced neutrophil chemoattractant 1 (CXCL1/CINC1), tumor necrosis factor-alpha (TNF-α), transforming growth factor beta 1 (TGF-ß1), basic fibroblast growth factor (bFGF) and alpha-smooth muscle actin (α-SMA) were measured. The histological evaluation was also performed by hematoxylin and eosin staining. RESULTS: There was a significant increase in blood pressure, prostate weight, prostate body weight ratio (PBR), tissue levels of MDA, IL-6, CXCL1/CINC1, TNF-α, TGF-ß1, bFGF and α-SMA in the SHR compared to the WKY rat. The ventral prostate in the SHR showed the morphological abnormalities compared to the WKY rat. Prostatic blood flow was decreased in the SHR. However, treatment with silodosin significantly restored the decreased prostatic blood flow in the SHR. Moreover, silodosin normalized tissue levels of MDA, IL-6, CXCL1/CINC1, TNF-α, TGF-ß1, bFGF and α-SMA, and it ameliorated ventral prostatic hyperplasia in the SHR excluding blood pressure. Silodosin decreased PBR but not prostate weight in the SHR. CONCLUSIONS: Silodosin can inhibit the progression of prostatic hyperplasia through a recovery of prostatic blood flow.

Surface-modified nanoparticles enhance transurothelial penetration and delivery of survivin siRNA in treating bladder cancer.

Penetration of the bladder permeability barrier (BPB) is a major challenge when treating bladder diseases via intravesical delivery. To increase transurothelial migration and tissue and tumor cell uptake, poly(lactic-co-glycolic acid; PLGA) nanoparticles (NP) were modified by addition of a low molecular weight (2.5 or 20 kDa) positively charged mucoadhesive polysaccharide, chitosan, to the NP surface. In designing these NPs, we balanced the adhesive properties of chitosan with the release and bioactivity of the siRNA. Chitosan-functionalized NPs demonstrated increased binding to and uptake in intravesically instilled mouse bladders and human ureter at 10 times the level of unmodified NPs. Furthermore, we extended the bioactivity of survivin siRNA in vitro for up to 9 days and demonstrated a decrease in proliferation when using chitosan-modified NPs relative to unmodified NPs. In addition, treatment of xenograft tumors with chitosan-modified NPs that encapsulate survivin siRNA (NP-siSUR-CH2.5) resulted in a 65% reduction in tumor volume and a 75% decrease in survivin expression relative to tumors treated with blank chitosan NPs (NP-Bk-CH2.5). Our low molecular weight chitosan delivery system has the capacity to transport large amounts of siRNA across the urothelium and/or to the tumor site, thus increasing therapeutic response.