Secretory autophagy-induced bladder tumour-derived extracellular vesicle secretion promotes angiogenesis by activating the TPX2-mediated phosphorylation of the AURKA-PI3K-AKT axis

Tumour angiogenesis is an independent risk factor for bladder cancer (BCa) progression, but viable and promising antiangiogenic targets are understudied. Secretory autophagy has received increasing interest recently, while the roles and executing mechanisms in the tumour microenvironment (TME) remain unclear. Herein, we found that active cathepsin B (CTSB) was upregulated in tumour tissues and serum EVs of 241 BCa patients from four cohorts and was significantly associated with poor prognosis. Starving TME (STME)-induced conventional autophagy in BCa cells elevated active CTSB levels by facilitating the expression and nuclear translocation of NFATC2. In addition, STME-induced secretory autophagy simultaneously led to markedly increased secretion of LC3-conjugated EVs loaded with active CTSB (EV-CTSB) into the TME. The increased exogenous active CTSB in endothelial cells by directly ingesting EV-CTSB prominently activated the TPX2-mediated phosphorylation of the AURKA-PI3K-AKT axis, increased VEGFA expression, and promoted angiogenesis. Our findings not only verify that EV-CTSB can be a promising target for antiangiogenic strategies in bladder cancer, but also reveal a novel action pattern based on secretory autophagy-induced EV secretion which is enlightening to explore crosstalk in the TME from various perspectives.

The role of matrix metalloproteinases in pathogenesis of human bladder cancer

Matrix metalloproteinases (MMPs) play an important role in many physiological and pathological processes, including neoplastic processes. They belong to a group of enzymes called endopeptidases and have the ability to hydrolyze all proteins in the extracellular matrix (ECM). They are produced in most connective tissue cells, macrophages, leukocytes, endothelial cells, microglial cells and in cancer cells. Neoplastic diseases are one of the main causes of death in Poland and in the world, therefore learning about the process of carcinogenesis seems to be particularly important. The process of carcinogenesis is currently widely studied and MMPs play one of the key roles in the development of cancer. They do this by regulating local tumor growth, stromal invasion, stimulating angiogenesis and metastasis formation. Bladder cancer is the 7th most common cancer in the male population and the 11th most common cancer in the world. In bladder cancer, most studies have been devoted to MMP-2 and MMP-9, that are enzymes responsible for the degradation of type IV collagen in the first place, which through the destruction of basement membranes and ECM, play an essential role in the tumor invasion process. Since bladder cancer is characterized by the ability to relapse, from the point of view of clinical practice it seems particularly important to develop a marker of early bladder tumor recurrence. MMPs detected in the urine and serum of patients with bladder cancer are potential factors that could play such a role.

HBXIP accelerates glycolysis and promotes cancer angiogenesis via AKT/mTOR pathway in bladder cancer

Abnormal metabolism and uncontrolled angiogenesis are two important characteristics of malignant tumors. Although HBXIP is known to be associated with a poor prognosis for bladder cancer (BC), its effects on glycolysis and angiogenesis in BC have not been investigated. BC prognosis and relative gene expression of HBXIP were analyzed using the GEPIA, UALCAN, and STRING databases. BC cell angiogenesis and glycolysis were assessed by vasculogenic mimicry and glycolysis assay. Human umbilical vein endothelial cell (HUVEC) viability, migration, and angiogenesis were assessed by CCK8, transwell, wound healing, and tube formation assays. The results showed that HBXIP was highly expressed in BC tissues and cells. Knockdown of HBXIP expression decreased the levels of glucose uptake, lactate production, and glycolytic enzyme expression in BC cells, and decreased cell viability and migration of HUVECs. Additionally, silencing HBXIP reduced the total length of tubes and number of intersections, and EPO and VEGF protein expression in BC cells and HUVECs. Furthermore, knockdown of HBXIP expression reversed cell viability, migration, tube formation, and vasculogenic mimicry under high glucose and lactate conditions. Mechanistically, silencing of HBXIP reduced the protein expression levels of pAKT-ser473 and pmTOR, and inhibition of HBXIP, AKT, and mTOR expression decreased glycolytic enzyme protein expression. Our findings suggest that HBXIP reduces glycolysis in BC cells via regulation of AKT/mTOR signaling, thereby blocking BC angiogenesis. Collectively, this study provides a potential strategy to target HBXIP and AKT/mTOR for regulating glycolysis progression concurrently with anti-angiogenesis effects, and thereby develop novel therapeutics for the treatment of BC.

The Interplay between Oxidative Stress, Inflammation and Angiogenesis in Bladder Cancer Development

In 2018, 550,000 people were diagnosed with bladder cancer (BC), of which nearly 200,000 people died. Moreover, men are 4 times more likely than women to be diagnosed with BC. The risk factors include exposure to environmental and occupational chemicals, especially tobacco smoke, benzidine and genetic factors. Despite numerous studies, the molecular basis of BC development remains unclear. A growing body of evidence suggests that inflammation, oxidant-antioxidant imbalance and angiogenesis disorders may play a significant role in the development and progression of bladder cancer. The patients with bladder cancer were characterised by an increased level of reactive oxygen species (ROS), the products of lipid peroxidation, proinflammatory cytokines and proangiogenic factors as compared to controls. Furthermore, it was shown that polymorphisms localised in genes associated with these pathways may modulate the risk of BC. Interestingly, ROS overproduction may induce the production of proinflammatory cytokines, which finally activated angiogenesis. Moreover, the available literature shows that both inflammation and oxidative stress may lead to activation of angiogenesis and tumour progression in BC patients.

Death from Transfusion-Transmitted Anaplasmosis, New York, USA, 2017

We report a death from transfusion-transmitted anaplasmosis in a 78-year-old man. The patient died of septic shock 2 weeks after a perioperative transfusion with erythrocytes harboring Anaplasma phagocytophilum. The patient's blood specimens were positive for A. phagocytophilum DNA beginning 7 days after transfusion; serologic testing remained negative until death.

Contrast-Enhanced Ultrasound Differentiation Between Low- and High- Grade Bladder Urothelial Carcinoma and Correlation With Tumor Microvessel Density

OBJECTIVES

Time-intensity curves (TICs) of contrast-enhanced ultrasound (CEUS) were analyzed retrospectively to differentiate between low-grade and high-grade bladder urothelial carcinoma, and to investigate correlation with tumor microvessel density (MVD).

METHODS

The data of 105 patients with pathologically confirmed bladder urothelial carcinoma (55 low-grade and 50 high-grade) were reviewed. Lesions were examined before surgery using conventional ultrasound and CEUS with TIC analysis. The TIC parameters time from peak to one-half the signal intensity (TPH) and the corresponding descending slope (DS) of the low-grade and high-grade groups were compared, and receiver operating characteristic curves constructed. The MVDs of the resectioned tissue specimens were quantified via immunohistochemistry for CD34.

RESULTS

Based on conventional ultrasound, the low-grade and high-grade groups were similar in tumor shape, number, topography, internal echo, height, width, and vascularity. The TPH of the high-grade group was significantly longer than that of the low-grade group, and the DS was lower. The cutoff points of TPH and DS for differentiating low-grade and high-grade bladder urothelial carcinoma were 48.06 seconds and 0.15 dB/seconds, respectively (area under the receiver operating characteristic curve = 0.79 for both). The mean MVDs per high-power field of the low-grade and high-grade groups were 41.39 16.65 and 51.03 20.16, respectively (P = .009). The TPH correlated linearly with MVD (P < .01), as did the DS (P < .01).

CONCLUSIONS

Contrast-enhanced ultrasound can be used to differentiate low from high-grade bladder urothelial carcinoma. The TIC parameters of CEUS reflect the MVD of bladder urothelial tumors and may be helpful for evaluating tumor angiogenesis, with implications for clinical diagnosis, treatment, and prognosis.

Ultrastructural immunohistochemical study of L-type amino acid transporter 1-4F2 heavy chain in tumor microvasculatures of N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) induced rat bladder carcinoma

Angiogenesis is essential for tumor growth, and an enhanced vasculature supplying nutrients and oxygen might reflect malignant potential. L-type amino acid transporter 1 (LAT1/4F2hc) comprises a major nutrient transport system responsible for the Na+-independent transport of large neutral amino acids. Seventy five to seventy eight percent N-butyl-N-(4-hydroxybutyl) nitrosamine-induced rat bladder carcinoma cells showed high LAT1/4F2hc expression. While the intracarcinoma microvasculatures of fenestrated endothelial cells highly expressing LAT1/4F2hc might progressively transport essential amino acids from the microvasculatures to the extracellular matrix, non-fenestrated endothelial cells and pericytes did not. The present study revealed that the tumor angiogenesis is one of target anti-L-type amino acid transporter 1 drug.

Ellagic Acid Inhibits Bladder Cancer Invasiveness and In Vivo Tumor Growth

Ellagic acid (EA) is a polyphenolic compound that can be found as a naturally occurring hydrolysis product of ellagitannins in pomegranates, berries, grapes, green tea and nuts. Previous studies have reported the antitumor properties of EA mainly using in vitro models. No data are available about EA influence on bladder cancer cell invasion of the extracellular matrix triggered by vascular endothelial growth factor-A (VEGF-A), an angiogenic factor associated with disease progression and recurrence, and tumor growth in vivo. In this study, we have investigated EA activity against four different human bladder cancer cell lines (i.e., T24, UM-UC-3, 5637 and HT-1376) by in vitro proliferation tests (measuring metabolic and foci forming activity), invasion and chemotactic assays in response to VEGF-A and in vivo preclinical models in nude mice. Results indicate that EA exerts anti-proliferative effects as a single agent and enhances the antitumor activity of mitomycin C, which is commonly used for the treatment of bladder cancer. EA also inhibits tumor invasion and chemotaxis, specifically induced by VEGF-A, and reduces VEGFR-2 expression. Moreover, EA down-regulates the expression of programmed cell death ligand 1 (PD-L1), an immune checkpoint involved in immune escape. EA in vitro activity was confirmed by the results of in vivo studies showing a significant reduction of the growth rate, infiltrative behavior and tumor-associated angiogenesis of human bladder cancer xenografts. In conclusion, these results suggest that EA may have a potential role as an adjunct therapy for bladder cancer.

Increased toll-like receptors and p53 levels regulate apoptosis and angiogenesis in non-muscle invasive bladder cancer: mechanism of action of P-MAPA biological response modifier

BACKGROUND

The new modalities for treating patients with non-muscle invasive bladder cancer (NMIBC) for whom BCG (Bacillus Calmette-Guerin) has failed or is contraindicated are recently increasing due to the development of new drugs. Although agents like mitomycin C and BCG are routinely used, there is a need for more potent and/or less-toxic agents. In this scenario, a new perspective is represented by P-MAPA (Protein Aggregate Magnesium-Ammonium Phospholinoleate-Palmitoleate Anhydride), developed by Farmabrasilis (non-profit research network). This study detailed and characterized the mechanisms of action of P-MAPA based on activation of mediators of Toll-like Receptors (TLRs) 2 and 4 signaling pathways and p53 in regulating angiogenesis and apoptosis in an animal model of NMIBC, as well as, compared these mechanisms with BCG treatment.

RESULTS

Our results demonstrated the activation of the immune system by BCG (MyD88-dependent pathway) resulted in increased inflammatory cytokines. However, P-MAPA intravesical immunotherapy led to distinct activation of TLRs 2 and 4-mediated innate immune system, resulting in increased interferons signaling pathway (TRIF-dependent pathway), which was more effective in the NMIBC treatment. Interferon signaling pathway activation induced by P-MAPA led to increase of iNOS protein levels, resulting in apoptosis and histopathological recovery. Additionally, P-MAPA immunotherapy increased wild-type p53 protein levels. The increased wild-type p53 protein levels were fundamental to NO-induced apoptosis and the up-regulation of BAX. Furthermore, interferon signaling pathway induction and increased p53 protein levels by P-MAPA led to important antitumor effects, not only suppressing abnormal cell proliferation, but also by preventing continuous expansion of tumor mass through suppression of angiogenesis, which was characterized by decreased VEGF and increased endostatin protein levels.

CONCLUSIONS

Thus, P-MAPA immunotherapy could be considered an important therapeutic strategy for NMIBC, as well as, opens a new perspective for treatment of patients that are refractory or resistant to BCG intravesical therapy.

Targeting endothelial connexin40 inhibits tumor growth by reducing angiogenesis and improving vessel perfusion

Endothelial connexin40 (Cx40) contributes to regulate the structure and function of vessels. We have examined whether the protein also modulates the altered growth of vessels in tumor models established in control mice (WT), mice lacking Cx40 (Cx40-/-), and mice expressing the protein solely in endothelial cells (Tie2-Cx40). Tumoral angiogenesis and growth were reduced, whereas vessel perfusion, smooth muscle cell (SMC) coverage and animal survival were increased in Cx40-/- but not Tie2-Cx40 mice, revealing a critical involvement of endothelial Cx40 in transformed tissues independently of the hypertensive status of Cx40-/- mice. As a result, Cx40-/- mice bearing tumors survived significantly longer than corresponding controls, including after a cytotoxic administration. Comparable observations were made in WT mice injected with a peptide targeting Cx40, supporting the Cx40 involvement. This involvement was further confirmed in the absence of Cx40 or by peptide-inhibition of this connexin in aorta-sprouting, matrigel plug and SMC migration assays, and associated with a decreased expression of the phosphorylated form of endothelial nitric oxide synthase. The data identify Cx40 as a potential novel target in cancer treatment.

Adjunctive use of narrow band imaging during transurethral resection/vaporization of bladder tumors to aid In identifying mucosal and sub-mucosal hypervascularity

For patients with non-muscle invasive bladder cancer, cystoscopy and transurethral resection/vaporization of the bladder tumor plays an integral role in the treatment of a given patient's bladder cancer. Although considered the current gold standard for tumor detection, traditional or white light cystoscopy has been shown to have its limitations visualizing both small papillary tumors and/or carcinoma in-situ. Current efforts have been directed to closing this gap with data demonstrating that by identifying these previously missed lesions, tumor recurrence and progression rates are reduced, thereby improving patient outcomes. Narrow Band Imaging, which can be used during cystoscopy and transurethral resection/vaporization of bladder tumors, can aid in visualizing mucosal and sub-mucosal hypervascularity--a probable surrogate for malignant lesions--potentially visualizing the boundaries of lesions that may have been missed during white light cystoscopy alone. This technique may produce equivalent visual markers with fewer logistical hurdles than currently available methods. In this article, we detail our technique for the adjunctive use of Narrow Band Imaging during cystoscopy and transurethral resection/vaporization of bladder tumors to aid in visualizing mucosal and sub-mucosal hypervascularity. Although not yet readily adopted, Narrow Band Imaging may be a practical and easy to use adjunct to existing methods in visualizing occult bladder lesions.

The preclinical activity of lenalidomide in indolent urothelial carcinoma

BACKGROUND

Lenalidomide is an IMiD® immunomodulatory drug, which may warrant evaluation in urothelial carcinoma (UC).

MATERIALS AND METHODS

The in vitro and in vivo activity of lenalidomide was evaluated in human and murine UC cell lines. Tumors were evaluated by immunohistochemistry for (CD31), cleaved caspase-3 (CC3) and CD3+/CD20+ lymphocyte infiltration. Cereblon, a molecular target of lenalidomide was analyzed by immunohistochemistry.

RESULTS

Significant pro-apoptotic activity, and reduction of cell viability was seen at low micromolar concentrations of lenalidomide against indolent human RT4 UC cells in vitro. Cereblon expression was quantitatively lower in sensitive RT4 cells compared to resistant 5637 cells. In RT4 xenografts, lenalidomide significantly reduced tumor size and CD31 expression, and increased expression of CC3 (p<0.05). Cereblon expression increased in lenalidomide-treated RT4 xenografts (p<0.05).

CONCLUSION

Lenalidomide demonstrated preclinical activity against superficially-invasive low-grade UC cells attributable to direct tumor cell apoptosis and anti-angiogenic activity. Clinical trials are warranted in patients with indolent UC.

[Expressions of CD133 and CD82/KAI1 in bladder urothelial carcinoma and their correlation with vasculogenic mimicry]

OBJECTIVE

To explore the expressions of CD133 and CD82/KAI1 in bladder urothelial carcinoma, their association with the clinicopathological factors and their roles in vasculogenic mimicry (VM) in the tumor.

METHODS

The expressions of CD133 and CD82/KAI1 and VM were detected by immunohistochemistry and histochemistry in 90 specimens of bladder urothelial carcinoma and 20 specimens of normal bladder epithelium tissue.

RESULTS

The positivity rates of CD133, CD82/KAI1 and VM in normal bladder epithelium tissue were 0, 90% and 0, showing significant differences from the rates of 65.6%, 31.1% and 31.1% in urothelial carcinoma, respectively (P<0.01). Positive expressions of CD133, CD82/KAI1 and VM were significantly correlated with pTNM stage and tumor relapse (P<0.01) but not with gender, age, or tumor numbers (P>0.05). CD133 expression was positively correlated with VM (P=0.487, P<0.05), and CD82/KAI1 expression was negatively correlated with VM (r=-0.452, P<0.01) and CD133 (r=-0.776, P<0.05).

CONCLUSION

The expressions of CD133 and CD82/KAI1 proteins are involved in the occurrence of VM in bladder urothelial carcinoma to contribute to the invasion and relapse of bladder carcinoma.

IL-6 expression regulates tumorigenicity and correlates with prognosis in bladder cancer

Identification of potential tumor markers will help stratify and identify a tumor's malignant potential and its response to specific therapies. IL-6 has been reported to be a predictor in various cancers. Therefore, the present study was performed to highlight the role of IL-6 in improving treatment and determining prognosis of bladder cancer. The human bladder cancer cell lines HT1376 and HT1197 were selected for cell and animal experiments, in which biological changes after experimental manipulation of IL-6 were explored, including tumor behavior and related signaling in bladder cancer. In addition, clinical specimens from 85 patients with muscle-invasive, and 50 with non-muscle invasive bladder cancers were selected for immunohistochemical staining to evaluate the predictive capacity of IL-6 in relation to clinical outcome. The data revealed that IL-6 was overexpressed in the bladder cancer specimens compared with non-malignant tissues at both mRNA and protein levels. Positive staining of IL-6 was significantly correlated with higher clinical stage, higher recurrence rate after curative treatment, and reduced survival rate. Tumor growth and invasive capability were attenuated when IL-6 was blocked. The underlying changes included decreased cell proliferation, less epithelial-mesenchymal transition (EMT), decreased DNA methyltransferase 1 expression and attenuated angiogenesis. In conclusion, our findings showed that IL-6 could be a significant predictor for clinical stage and prognosis of bladder cancer. Moreover, targeting IL-6 may be a promising strategy for treating bladder cancer.

Microbubble and ultrasound radioenhancement of bladder cancer

BACKGROUND

Tumour vasculature is an important component of tumour growth and survival. Recent evidence indicates tumour vasculature also has an important role in tumour radiation response. In this study, we investigated ultrasound and microbubbles to enhance the effects of radiation.

METHODS

Human bladder cancer HT-1376 xenografts in severe combined immuno-deficient mice were used. Treatments consisted of no, low and high concentrations of microbubbles and radiation doses of 0, 2 and 8 Gy in short-term and longitudinal studies. Acute response was assessed 24 h after treatment and longitudinal studies monitored tumour response weekly up to 28 days using power Doppler ultrasound imaging for a total of 9 conditions (n=90 animals).

RESULTS

Quantitative analysis of ultrasound data revealed reduced blood flow with ultrasound-microbubble treatments alone and further when combined with radiation. Tumours treated with microbubbles and radiation revealed enhanced cell death, vascular normalisation and areas of fibrosis. Longitudinal data demonstrated a reduced normalised vascular index and increased tumour cell death in both low and high microbubble concentrations with radiation.

CONCLUSION

Our study demonstrated that ultrasound-mediated microbubble exposure can enhance radiation effects in tumours, and can lead to enhanced tumour cell death.

Evaluation of bladder microvasculature with high-resolution photoacoustic imaging

We explored the potential of an emerging laser-based technology, photoacoustic imaging (PAI), for bladder cancer diagnosis through high-resolution imaging of microvasculature in the bladder tissues. Imaging results from ex vivo canine bladders demonstrated the excellent ability of PAI in mapping three-dimensional microvasculature in optically scattering bladder tissues. By comparing the results from human bladder specimens affected by cancer to those from the normal control, the feasibility of PAI to differentiate malignant from benign bladder tissues was also explored. The distinctive morphometric characteristics of tumor microvasculature can be seen in the images from cancer samples, suggesting that PAI may allow in vivo assessment of neoangiogenesis that is closely associated with bladder cancer generation and progression. By presenting subsurface morphological and physiological information in bladder tissues, PAI, when performed in a similar way as in conventional endoscopy, provides an opportunity for improved diagnosis, staging, and treatment guidance of bladder cancer.

[Evaluation of HER2 protein overexpression in non-muscle-invasive bladder cancer with emphasis on tumour grade and recurrence]

OBJECTIVE

To evaluate the prognostic value of HER2 expression in non-muscle invasive bladder transitional cell carcinoma (TCC) with special emphasis in the high grade population. MATERIALS AND METHODS (PATIENTS): Tissue microarrays (TMA) were performed with representative TUR-B specimens from 84 patients with non-muscle invasive bladder TCC (40 pT1GII and 44 pT1GIII) treated in our institution. Depth of invasion and grade were uniformly assigned by the same pathologist who performed blind immunohistochemical analysis with Hercep test: 3+ was considered strong positive HER2 overexpression. Other clinico-pathological variables were also assessed.

RESULTS

HER2 protein overexpression was detected in 30/44 (68.2%) pT1GIII lesions and predicted recurrence in this subgroup of bladder TCC (p<0.01). Negative HER2 expression was detected in 26/40 (65%) cases with pT1GII TCC, and this condition was more frequent in unifocal tumours, without angiogenesis, with low recurrence rate and without progression. Recurrence-free survival can also be anticipated by HER 2 expression within pT1GII tumours (p<0.01).

CONCLUSION

HER2 expression using Hercep test may be useful to predict recurrence in non-muscle invasive bladder TCC. The potential application of this study, especially regarding prediction of response to BCG, should be prospectively confirmed in multi-institutional trials.

High-magnification vascular imaging to reject false-positive sites in situ during Hexvix® fluorescence cystoscopy

Fluorescence imaging for detection of non-muscle-invasive bladder cancer is based on the selective production and accumulation of fluorescing porphyrins-mainly, protoporphyrin IX-in cancerous tissues after the instillation of Hexvix®. Although the sensitivity of this procedure is very good, its specificity is somewhat limited due to fluorescence false-positive sites. Consequently, magnification cystoscopy has been investigated in order to discriminate false from true fluorescence positive findings. Both white-light and fluorescence modes are possible with the magnification cystoscope, allowing observation of the bladder wall with magnification ranging between 30× for standard observation and 650×. The optical zooming setup allows adjusting the magnification continuously in situ. In the high-magnification (HM) regime, the smallest diameter of the field of view is 600 microns and the resolution is 2.5 microns when in contact with the bladder wall. With this cystoscope, we characterized the superficial vascularization of the fluorescing sites in order to discriminate cancerous from noncancerous tissues. This procedure allowed us to establish a classification based on observed vascular patterns. Seventy-two patients subject to Hexvix® fluorescence cystoscopy were included in the study. Comparison of HM cystoscopy classification with histopathology results confirmed 32∕33 (97%) cancerous biopsies and rejected 17∕20 (85%) noncancerous lesions.

[The diagnostic value of microsatellite LOH analysis and the prognostic relevance of angiogenic gene expression in urinary bladder cancer]

Bladder cancer is the second most common malignancy affecting the urinary system. Currently, histology is the only tool that determines therapy and patients' prognosis. As the treatment of non-invasive (Ta/T1) and muscle invasive (T2-T4) bladder tumors are completely different, correct staging is important, although it is often hampered by disturbing factors. Molecular methods offer new prospects for early disease detection, confirmation of unclear histological findings and prognostication. Applying molecular biological methods, the present study is searching for answers to current diagnostic and prognostic problems in bladder carcinoma. We analyzed tumor, blood and/or urine samples of 334 bladder cancer patients and 117 control individuals. Genetic alterations were analyzed in urine samples of patients and controls, both by PCR-based microsatellite loss of heterozigosity (LOH) analysis using 12 fluorescently labeled primers and by DNA hybridization based UroVysion FISH technique using 4 probes, to assess the diagnostic values of these methods. Whole genome microsatellite analysis (with 400 markers) was performed in tumor and blood specimens of bladder cancer patients to find chromosomal regions, the loss of which may be associated with tumor stage. Furthermore, we assessed the prognostic value of Tie2, VEGF, Angiopoietin-1 and -2. We concluded that DNA analysis of voided urine samples by microsatellite analysis and FISH are sensitive and non-invasive methods to detect bladder cancer. Furthermore, we established a panel of microsatellite markers that could differentiate between non-invasive and invasive bladder cancer. However, further analyses in a larger cohort of patients are needed to assess their specificity and sensitivity. Finally, we identified high Ang-2 and low Tie2 gene expression as significant and independent risk factors of tumor recurrence and cancer related survival.

A digital frequency ramping method for enhancing Doppler flow imaging in Fourier-domain optical coherence tomography

A digital frequency ramping method (DFRM) is proposed to improve the signal-to-noise ratio (SNR) of Doppler flow imaging in Fourier-domain optical coherence tomography (FDOCT). To examine the efficacy of DFRM for enhancing flow detection, computer simulation and tissue phantom study were conducted for phase noise reduction and flow quantification. In addition, the utility of this technique was validated in our in vivo clinical bladder imaging with endoscopic FDOCT. The Doppler flow images reconstructed by DFRM were compared with the counterparts by traditional Doppler FDOCT. The results demonstrate that DFRM enables real-time Doppler FDOCT imaging at significantly enhanced sensitivity without hardware modification, thus rendering it uniquely suitable for endoscopic subsurface blood flow imaging and diagnosis.

Targeting vasculature in urologic tumors: mechanistic and therapeutic significance

Recent advances toward understanding the molecular mechanisms regulating cancer initiation and progression provide new insights into the therapeutic value of targeting tumor vascularity by interfering with angiogenic signaling pathways. The functional contribution of key angiogenic factors toward increased vascularity characterizing metastatic tumors and their therapeutic exploitation is considered in three major urologic malignancies, renal, bladder, and prostate cancer. With the realization that the success of the therapeutic efficacy of the various anti-angiogenic approaches for the treatment of urologic tumors has yet to be proven clinically, the challenge remains to select critical angiogenesis pathways that can be targeted for an individual tumor. Here we discuss the major mechanisms that support formation of vasculature in renal, bladder, and prostate tumors and the current results of targeting of specific molecules/regulators for therapeutic intervention against metastastic disease.

Hypoxia-inducible factor-1alpha expression correlates with focal macrophage infiltration, angiogenesis and unfavourable prognosis in urothelial carcinoma

BACKGROUND

Hypoxia inducible factor (HIF)-1alpha is a critical regulatory protein of cellular response to hypoxia and is closely related to angiogenic process.

AIMS

To explore the potential role and the prognostic value of HIF-1alpha in urothelial carcinoma (UC).

METHODS

Clinicopathological and follow-up data on 99 UC cases were reviewed and immunostained for HIF-1alpha, CD68, vascular endothelial growth factor (VEGF) and CD34 antigen. Tumour-associated macrophage (TAM) counts and HIF-1alpha expression were compared with clinicopathologic characteristics, overall survival (OS) and disease-free survival rates (DFS).

RESULTS

High expression of HIF-1alpha was detected in 55 of 99 (55.6%) tumours. HIF-1alpha expression was correlated with tumour size, histological grade, tumour invasiveness and recurrence. VEGF and microvessel density (MVD) demonstrated their positive correlation with HIF-1alpha overexpression, supporting the correlation of HIF-1alpha up-regulation with tumour angiogenesis. Higher TAM infiltration was identified in high expression of HIF-1alpha cases rather than HIF-1alpha low expression cases (p = 0.002). Kaplan-Meier analysis found that HIF-1alpha overexpression and high TAM count was only associated with worse DFS (p = 0.009, p = 0.023) but was not associated with OS (p = 0.696, p = 0.141). Multivariate analyses indicated only tumour size (p = 0.038) to be an independently significant prognostic factor for OS, in addition, HIF-1alpha expression (p = 0.011), as well as histological grade (p = 0.038), and MVD (p = 0.004), to be independently significant prognostic factors for DFS.

CONCLUSIONS

Our results indicate that HIF-1alpha is a key regulator of the angiogenic cascade. We show that HIF-1alpha is an independent prognostic factor for disease-free survival.

Bladder cancer angiogenesis and metastasis--translation from murine model to clinical trial

In the majority of cases, death from bladder cancer results from metastatic disease. Understanding the closely linked mechanisms of invasion, metastasis and angiogenesis in bladder cancer has allowed us to develop new therapeutic strategies that harbor the promise of decisive improvements in patient survival. The essential link between cell based experiments and the translation of novel agents into human patients with bladder cancer is the animal model. With emphasis on the orthotopic xenograft model, this review outlines some key mechanisms relevant to angiogenesis and the development of metastasis in bladder cancer. We highlight especially pathways related to MMP-9, IL-8, VEGF and EGFR. Most commonly, expression patterns of these markers in patients have correlated to disease progression and patient survival, which has led to laboratory investigations of these markers and eventually novel targeted therapies that are translated back into the clinic by means of clinical trials. Although imperfect in their translatability into clinical efficacy, animal models remain a critical tool in bladder cancer research.

Targeted therapies in bladder cancer--an update

Intravesical immuno- and chemotherapy, surgery, and systemic chemotherapy are all critical elements in our management of patients with bladder cancer. Despite our advances with these modalities, we continue to seek newer treatment paradigms to improve patient outcome. Targeted therapy with novel agents directed at specific molecular pathways is a promising avenue to achieve such progress. This manuscript is based on a talk given at the Spring Session of the Society of Urologic Oncology in May 2006. Here, we focus on targeting growth factors and their receptors in bladder cancer. In particular, we summarize our own and others' ongoing basic science, translational, and clinical research in this field. Foremost in this line of study is the epidermal growth factor receptor (EGFR)-targeted therapy with small molecule inhibitors and monoclonal antibodies. We discuss the rationale for EGFR-directed therapy in bladder cancer. The clinical efficacy has been disappointing, and extensive work has been done to characterize molecular markers for predicting response. Some of our own preclinical findings related to platelet derived growth factor-beta (PDGFR-beta) and some background on ongoing clinical trials targeting human EGF receptor 2 (HER2) are summarized. Fibroblast growth factor 3 (FGFR3) offers promise as a potential target for therapy of both superficial and invasive disease. The role of FGFR3 mutations in bladder cancer is reviewed. Finally, we discuss the targeting of VEGF. Ultimately, it may be the use of multi-kinase inhibitors or the combination of different inhibitors to various targets that yields the best results.

Evaluation of hypoxia-mediated growth factors in a novel bladder cancer animal model

BACKGROUND AND AIM

The outcome of advanced transitional cell carcinoma (TCC) is poor. Changes taking place in the tumor microenvironment are receiving increased scrutiny. Hypoxia is the key to increased expression of HIF-1alpha (hypoxia-inducible factor 1alpha) resulting in increased expression of growth factors (e.g. vascular endothelial growth factor (VEGF), epidermal growth factor (EGF)). The aim of our study was to establish an animal model with modulatable tumor hypoxia. Resulting tumor growth and growth factors were assessed.

MATERIALS AND METHODS

Low Hb levels were induced in rats by total body irradiation (5 Gy). Twenty animals received EPO erythropoietin (EPO), 1000 IE/kg/week subcutaneously). After subcutaneous injection of NBT-II cells a weekly determination of Hb concentration, leukocyte counts and tumor volume were performed. Serum VEGF levels were quantified and oxygen Hb saturation in healthy tissue and tumors were measured by percutaneous laser spectroscopy. HIF-1alpha and VEGF were examined immunohistochemically.

RESULTS

Reduced O2 supply promoted expression of HIF-1alpha and VEGF. Low oxygen availability was essential for tumor growth. EPO improved the O2 supply and decreased expression of growth factors but did not reduce tumor volumes.

CONCLUSION

Based on these studies, treatment of low Hb levels appears reasonable in TCC. O2 supply is improved and expression of tumor growth factors is decreased. Tumor volumes did not differ between the groups, causatively adverse effects of EPO overtreatment might negatively affect microcirculation. Restoring low Hb levels and improvement in the O2 supply resulted in tumor shrinkage.

Differential expression of vascular endothelial growth factor165b in transitional cell carcinoma of the bladder

Angiogenesis or the development of new blood vessels from the surrounding vasculature is essential for the growth and progression of solid tumors. Vascular endothelial growth factor (VEGF), a positive regulator of angiogenesis, plays a pivotal role in tumor angiogenesis and shows a high expression in almost all known tumors, including transitional cell carcinoma (TCC) of the bladder. A novel isoform, VEGF(165)b containing a novel exon 9, was recently identified in renal cell carcinoma and was shown to be down-regulated and inhibitory in nature. We aimed to analyze quantitatively expression of this isoform, VEGF(165)b, in TCC of the bladder and compare it to the benign part of the same organ. A real-time reverse transcriptase polymerase chain reaction protocol was set up to quantitate simultaneously the messenger ribonucleic acid levels of VEGF and VEGF(165)b from 34 clinical samples representing bladder cancer and matched benign tissue. Expression of VEGF(165)b showed a >or=3.0-fold change in 27 of 34 (79%) bladder tumors than the benign samples. Increased expression of VEGF(165)b was seen in superficial tumors as compared to invasive tumors, which was statistically significant (P < 0.001). Therefore, VEGF(165)b was up-regulated in TCC of the bladder.

The role of the endothelin axis and microvessel density in bladder cancer - correlation with tumor angiogenesis and clinical prognosis

Endothelin-1 (ET-1) and its receptors, entothelin-A (ETAR) and endothelin-B (ETBR), commonly referred to as the endothelin (ET)-axis, are involved in tumor biology and growth. We investigated the effects of the ET-axis on microvessel density (MVD) and the clinicopathological parameters of patients with invasive bladder cancer. Paraffin tumor sections of 120 patients who had undergone radical cystectomy were assessed immunohistochemically using mono- and polyclonal antibodies for ET-1, ETAR, ETBR and CD34 (MVD). Staining intensities were analyzed semiquantitatively and the MVD was calculated as vessels per field. The results were correlated with various pathological and clinical factors, as well as with disease-free and overall survival. Transitional cell carcinomas (MVD=23.7) were better vascularized than squamous cell carcinomas (MVD=17.8, p=0.04). Organ-confined tumors (MVD=32.2) were better vascularized than T3- and T4-tumors (MVD=21.2, p=0.02) and ET-1 was overexpressed in this subgroup (p=0.027). Patients with metastatic regional lymph nodes (MVD=20.9) tended to have less MVD than patients without regional lymph node metastases (MVD=24.1) (p=0.15). The account of MVD did not reveal any significant differences in disease-free or overall survival. Organ-confined tumors and ET-1 overexpression are associated with upregulated microvessel density. These results suggest that MVD and ET-1 could be considered good prognostic factors.

Ein Molekül, zwei Gesichter

BACKGROUND

Angiogenesis is a prerequisite for tumor growth and metastasis in which CEACAM1 plays an essential role.

PATIENTS AND METHODS

The role of CEACAM1 in vascularization and invasion of prostate and bladder cancer was studied.

RESULTS

Our analyses demonstrate an epithelial downregulation of CEACAM1 in superficial bladder tumors and in PIN of the prostate. Concurrently, CEACAM1 is upregulated in endothelial cells of tumor blood vessels. CEACAM1 knockdown in tumor cell lines of the prostate and urinary bladder via siRNA results in an increase of tumor vascularization while CEACAM1 overexpression in these cells suppresses it.

CONCLUSIONS

CEACAM1-induced signaling mechanisms play a role in induction of angiogenesis in superficial tumors of the prostate and bladder. Strategies to either conserve the epithelial CEACAM1 or to target endothelial CEACAM1 might be useful for an antiangiogenic therapy of bladder and prostate cancer.

Combination therapy with IFN-alpha plus bortezomib induces apoptosis and inhibits angiogenesis in human bladder cancer cells

In a recent study, we showed that the proteasome inhibitor bortezomib sensitizes human bladder cancer cells to IFN-induced cell death. Here, we characterized the molecular mechanisms underlying the antitumoral effects of the combination in more detail. Bortezomib synergized with IFN-alpha to promote apoptosis via a tumor necrosis factor-related apoptosis-inducing ligand-associated mechanism but did not inhibit production of proangiogenic factors (vascular endothelial growth factor, basic fibroblast growth factor, and interleukin-8) in human UM-UC-5 cells. In contrast, exposure to the combination did not increase the levels of apoptosis in human UM-UC-3 cells but did inhibit the production of basic fibroblast growth factor and vascular endothelial growth factor. Studies with tumor xenografts confirmed that combination therapy with bortezomib plus IFN-alpha was effective in both models but that the effects were associated with differential effects on tumor necrosis factor-related apoptosis-inducing ligand-associated apoptosis (predominant in UM-UC-5) versus inhibition of angiogenesis (predominant in UM-UC-3). Together, our results show that combination therapy with IFN-alpha plus bortezomib is effective but can work via different mechanisms (apoptosis versus angiogenesis inhibition) in preclinical models of human bladder cancer.

[Gene therapy of bladder cancer by using recombinant adeno-associated virus-endostatin: experiments in vitro and in vivo]

OBJECTIVE

To package recombinant adeno-associated virus-endostatin (rAAV-ES) and study its anti-tumor effect in vitro and in vivo.

METHODS

rAAV-ES was packaged with co-transfection technique and transfected into the human bladder cancer cells of the line EJ. 24 h later ELISA was used to examine the concentration of ES in the supernatant. The inhibition of human umbilical veins endothelial cells (HUVECs) chemotactic movement were examined by Transwell system. Nude Balb/c mice were divided into 4 groups: (1) 5 mice were inoculated with the EJ cells transfected with rAAV-ES or rAAV-enhanced yellow fluorescence protein (rAAV-EYFP) for 3 days to the subcutaneous tissues of bilateral shoulders so as to observe the growth of tumor. (2) 24 mice were injected with rAAV-ES intramuscularly and then the serum ES was examined every 10 days since the 10 th day after the injection. (3) 36 mice were randomly subdivided into 3 equal subgroups to be injected with rAAV-ES, rAAV-EYFP, or RPMI medium, inoculated with EJ cells 2 weeks later, and then killed 50 days later to observe the size of tumor. (4) 4 healthy mice and 4 mice injected with rAAV-ES for 8 weeks were killed with their hearts and brains taken out to observe the side effects.

RESULTS

rAAV-ES was packaged successfully. The ES concentration in the supernatant of culture fluid of the EJ cell transfected with rAAV-ES was 54.09 ng/ml. The inhibition rate of the HUVECs chemotactic movement was 37.45%. The xenograft formation rate was 2/5 for the EJ cells transfected with rAAV-ES. The serum ES levels of the mice injected with rAAV-ES remained high. The tumor size in the mice injected with rAAV-ES was significantly smaller than those of the other groups (both P < 0.01). No pathological changes was found in the hearts and brains in the mice injected with rAAV-ES.

CONCLUSION

rAAV-ES inhibits tumor angiogenesis, and tumor formation and progression. Successful packaging of rAAV-ES has laid a foundation for gene therapy of bladder cancer.

Sunitinib malate and sorafenib may be beneficial at the treatment of advanced bladder cancer due to their anti-angiogenic effects

Due to the poor prognosis of advanced bladder carcinoma and the insufficient affects of the chemotherapy agents for this disease, the investigation of the novel genetic and pharmacologic agents including anti-angiogenic agents that can target pathway-specific molecules has been the subject of several publications especially for the last 2 years. Although the clinical trials of these agents are still lacking, the experimental and the preliminary studies are giving hope for the future treatment of advanced bladder carcinoma. Sunitinib malate and sorafenib are the novel food and drug administration (FDA) approved anti-angiogenic agents, which have recently been demonstrated to improve the progression-free survival in patients with metastatic renal cell carcinoma. The main mechanism of these two drugs are defined as preventing the tumor growth by the inhibition of angiogenesis and the induction of apoptosis and necrosis via acting on different types of vascular endothelial growth factor (VEGF) such as the several agents which have been demonstrated to be beneficial for bladder carcinoma. According to this knowledge we suggest that these two new agents may also increase the progression-free survival of the patients with advanced bladder carcinoma due to their anti-angiogenic and tumor cell apoptotic effects. We believe that the evaluation of the effects of these agents on bladder cancer population by clinical, prospective and placebo controlled studies may prove our hypothesis and add critical findings to the literature which is still lacking.

Lymphovascular invasion as a prognostic tool for advanced bladder cancer

PURPOSE OF REVIEW

Lymphovascular invasion has been correlated with the metastatic ability of the cancer. It has been studied in urological tumours at every location, but it has only been included as a prognostic factor in the TNM (tumour, lymph nodes and metastasis) classification of germ cell testicular tumours. The purpose of this evaluation is to look into the predictive value of lymphovascular invasion in locally advanced bladder cancer.

RECENT FINDINGS

Studies carried out in patients who underwent cystectomy report a lymphovascular invasion incidence of 30-50% of the cases. All of them agree that there is a correlation between the presence of lymphovascular invasion and disease evolution, but some authors consider that only blood vessel invasion is a statistically significant independent prognostic factor, and others find that this happens only in lymph node-negative cases.

SUMMARY

All papers stress the prognostic value of lymphovascular invasion, most of them as an independent factor, but there are still some doubts as to its use in clinical decision making, owing to the poor diagnosis reproducibility. This is why it would be necessary to reach a consensus on strict diagnostic criteria as soon as possible to be able to incorporate this prognostic factor in clinical practice.

Hypoxia-inducible factors HIF-1alpha and HIF-2alpha expression in bladder cancer and their associations with other angiogenesis-related proteins

Hypoxia-inducible factors (HIF-1alpha and HIF-2alpha) are closely related protein complexes that activate transcription of target genes in response to hypoxia. The immunohistochemical expression of these two proteins was investigated in 144 bladder cancer tissue samples and correlated with standard clinicopathological features, in order to elucidate their prognostic significance. We also evaluated their possible associations with other angiogenesis related markers such as microvessel density (MVD), vascular endothelial growth factor, thymidine phosphorylase, tenascin, fibronectin, p53 and bcl-2 to further clarify their implication in tumor stroma vascularization. Nuclear HIF-1alpha expression in tumor cells was detected in 57.1% of the cases. A trend of correlation of this expression with poorly differentiated tumors was observed. In addition, HIF-1alpha expression was positively correlated with stromal cells thymidine phosphorylase expression. Tumors that were progressed in muscle-infiltrating disease showed a higher HIF-1alpha expression. A higher HIF-1alpha expression was also observed in tumors with an in situ component. In tumor cells, low HIF-2alpha expression was observed in 6.3%, moderate in 31.9% and high in 61.8% of the cases. A trend of correlation of this expression with MVD was observed. In addition, HIF-2alpha expression was positively correlated with thymidine phosphorylase and fibronectin expression. A lower HIF-2alpha expression was detected in tumors that recurred earlier in univariate methods of analysis. HIF-2alpha was expressed in tumor stroma associated cells in 53.5% of specimens and was correlated with advance tumor stage, thymidine phosphorylase and tenascin expression. There was no statistically significant difference in the expression of both HIF-1alpha and HIF-2alpha between primary and recurrent tumors. In multivariate analysis including T stage, T grade, multifocality and T size, both HIF-1alpha and HIF-2alpha expression were not considered dependent in the prediction of recurrence or progression. In conclusion, the results of the present study indicate that HIF-1alpha and HIF-2alpha expression may help to predict recurrence or progression to muscle invasive disease but not as independent prognostic factors. In addition, the expression of HIF-1alpha and HIF-2alpha, appear to play a role in bladder cancer, vascularization possibly and in cooperation with other angiogenic factors.

Molecular Pathways in Invasive Bladder Cancer: New Insights Into Mechanisms, Progression, and Target Identification

Papillary and invasive cancers of the urinary bladder appear to evolve and progress through distinct molecular pathways. Invasion in bladder cancer forebodes a graver prognosis, and these tumors are generally characterized by alterations in the p53 and retinoblastoma (RB) pathways that normally regulate the cell cycle by interacting with the Ras–mitogen activated protein kinase signal transduction pathway. Tumor angiogenesis further contributes to the neoplastic growth by providing a constant supply of oxygen and nutrients. Distinct epigenetic and genetic events characterize the interplay between the molecules involved in these pathways, thus affording their use as indicators of prognosis. Efforts are now underway to construct molecular panels comprising multiple markers that can serve as more robust predictors of outcome. While clinical trials for targeted chemotherapy for bladder cancer have commenced, novel genetic and pharmacologic agents that can target pathway-specific molecules are currently under development. The next generation of clinical management for urothelial carcinoma will witness the use of multimarker panels for prognostic prediction and combination therapy directed at novel molecular targets for treatment.

Up-regulation of endothelial delta-like 4 expression correlates with vessel maturation in bladder cancer

PURPOSE

Angiogenesis and vascular endothelial growth factor (VEGF) expression are associated with a poor outcome in bladder cancer. To understand more about the mechanisms, we studied the role of delta-like 4 (DLL4), an endothelial-specific ligand of the Notch signaling pathway, in bladder cancer angiogenesis.

EXPERIMENTAL DESIGN

The expression of DLL4, CD34, and VEGF were studied in a cohort of 60 bladder tumors and 10 normal samples using quantitative PCR. In situ hybridization was used to study the pattern of DLL4 expression in 22 tumor and 9 normal samples. Serial sections were also stained for CD34 and alpha-smooth muscle actin (alpha-SMA) using conventional immunohistochemistry.

RESULTS

The expression of DLL4 was significantly up-regulated in superficial (P < 0.01) and invasive (P < 0.05) bladder cancers. DLL4 expression significantly correlated with CD34 (P < 0.001) and VEGF (P < 0.001) expression. The in situ hybridization studies showed that DLL4 was highly expressed within bladder tumor vasculature. Additionally, DLL4 expression significantly correlated with vessel maturation as judged by periendothelial cell expression of alpha-SMA, 98.7% of DLL4-positive tumor vessels coexpressed alpha-SMA, compared with 64.5% of DLL4-negative tumor vessels (P < 0.001). High DLL4 expression may have prognostic value in superficial and invasive bladder.

CONCLUSION

DLL4 expression is associated with vascular differentiation in bladder cancer; thus, targeting DLL4 may be a novel antiangiogenic therapy.

An endogenous inhibitor of angiogenesis derived from a transitional cell carcinoma: clipped beta2-glycoprotein-I

BACKGROUND

Invasive cell carcinoma of the bladder often develops after complete transurethral excision of superficial transitional cell carcinoma. It has been postulated that primary tumors release angiogenesis-blocking proteins which suppress distant metastases. We have identified an endogenous protein which might be responsible for tumor dormancy.

METHODS

A transitional cell carcinoma cell line was developed (UMUC-3i) which inhibits the growth of a tumor implant at a distant site in SCID mice. Conditioned media of UMUC-3i cultured cells was first pooled and then fractioned, and the capacity of individual components to block endothelial cell growth was tested. The protein fraction responsible for blocking endothelial cell growth was identified by N-terminal amino acid sequencing as well as by mass-spectrometry. The effects of the purified protein in preventing endothelial cell proliferation and tube formation in an in vitro angiogenesis assay was investigated.

RESULTS

The plasma protein beta(2)-glycoprotein-I (beta(2)gpI) was isolated and identified from conditioned medium of UMUC-3i cultured cells. Based on the in vitro angiogenesis assay, beta(2)gpI strongly inhibited endothelial cell growth and tube formation, whereby the inhibitory activity corresponded to the clipped version of beta(2)gpI (cbeta(2)gpI). Clipping was induced by adding plasmin at a molar ratio 1:15 (plasmin:substrate). Further analysis indicated that cbeta(2)gpI effects were mediated by annexin II surface receptors expressed on endothelial cells.

CONCLUSIONS

cbeta2gpI may be involved in blocking angiogenic processes and bladder cancer progression. In this case, cbeta2gpI may be a promising tool in bladder cancer therapy.

Angiotensin II type 1 receptor antagonist candesartan as an angiogenic inhibitor in a xenograft model of bladder cancer

PURPOSE

There have been several studies on the antitumor activity of angiotensin II type 1 receptor (AT1R) antagonists. In this study, we evaluated the efficacy of the AT1R antagonist candesartan in bladder cancer.

EXPERIMENTAL DESIGN

For the study in vitro, human bladder cancer cells (KU-19-19) were cultured with or without angiotensin II and candesartan. Various cytokines and cell viability were analyzed. For the study in vivo, a tumor xenograft model was prepared in nude mice using KU-19-19 cells. Mice were given candesartan daily by oral gavage. Microvessel density, expression of vascular endothelial growth factor (VEGF), and apoptosis were assessed.

RESULTS

Candesartan did not induce direct toxicity in KU-19-19 cells, but VEGF and interleukin-8 were significantly lower in candesartan-treated cells (2.55 +/- 0.25 and 6.58 +/- 0.48 pg/10(3) cells) than in the angiotensin II-treated control cells (3.16 +/- 0.42 and 7.91 +/- 0.69 pg/10(3) cells). In mice, candesartan both at doses of 2 and 10 mg/kg/d significantly suppressed tumor growth in mice (35.4% and 33.5% reduction in tumor volume). Microvessel density was significantly decreased by candesartan (9.8 +/- 2.8 per field) compared with the control group (17.6 +/- 6.0 per field), and VEGF expression was significantly suppressed by this AT1R antagonist. However, candesartan did not induce apoptosis of cancer cells in the tumor.

CONCLUSIONS

Specific blockade of AT1R prevented bladder tumor growth by inhibiting angiogenesis. However, its antitumor effect was not due to direct toxicity. Because AT1R antagonists are widely used to treat hypertension, and a 2 mg/kg/d dose level of candesartan is clinically achievable, this AT1R antagonist could also be used to treat bladder cancer.

Preliminary report on analysis of bladder-wall vasculature using conjunctival microvascular analysis in patients with and without transitional-cell carcinoma

PURPOSE

To develop a technique to analyze the bladder microvasculature during cystoscopy to assess the conjuctival microvascular morphology at the capillary level. This technique could be an adjunct to visual examination of the bladder during cystoscopy for diseases that are presumed to affect the vasculature.

PATIENTS AND METHODS

Subjects with transitional-cell carcinoma (TCC) were chosen because of their frequency of cystoscopy. A total of 12 male patients, ages 45 to 80 years, underwent cystoscopy: four without TCC and eight with TCC by bladder biopsy. The images were digitally recorded and enhanced using a custom image-analysis system. The blood vessel length (VL) and diameter (VD) and blood vessel volume (BVV) were measured.

RESULTS

The VD was significantly greater in TCC than in non-TCC patients only in the lower-order vessels. The VL was significantly longer in TCC than in non-TCC, again in the lower-order vessels. In the higherorder vessels, the VL was significantly shorter in TCC than in non-TCC. The BVV in the lower-order vessels was significantly greater in TCC than in non-TCC patients.

CONCLUSIONS

Differences exist in the morphology of surface microvessels between TCC and non-TCC bladders. Using the current technique, capillaries (VD < 10 microm) are not visible, so refinement of imaging and recording technologies is required to measure capillaries in order to simulate microvascular morphometry in the conjuctiva.

Mechanisms of Disease: angiogenesis in urologic malignancies

Angiogenesis is critical for growth of tumors and their metastasis. In this article we review the literature on studies of angiogenesis pathways and markers for renal cancer, prostate cancer and bladder cancer. Overall, there is clear evidence that markers of angiogenesis and expression of angiogenic factors are associated with adverse outcomes in each of these tumor types. Relatively few angiogenic pathways have been investigated so far, although over 50 factors are known to be involved, and little has been studied on the antiangiogenic pathways and their suppression. The failing in many of the studies is small size and lack of suitable statistical analysis. Nevertheless, this review demonstrates the importance of these pathways and the need to develop selection criteria for patients who are candidates for antiangiogenic therapies. On the basis of the expression profiles reported so far, therapies that target vascular endothelial growth factor should be considered for the treatment of renal, prostate and bladder cancers. As most tumors express factors that are involved in multiple angiogenic pathways, further research is needed to determine which are coregulated and what the most common patterns are.

Development of fetal haemoglobin-blood cells (F cells) within colorectal tumour tissues

AIM

To evaluate the sources of fetal haemoglobin (HbF) as an indicator in cancer. An immunohistochemical study was carried out on some of the most common kinds of cancer. All of these cancers had serologically high levels of HbF as evaluated previously.

METHODS

Immunoaffinity-purified anti-HbF was immunohistochemically used to study F cell distribution in the following cancers: colorectal adenocarcinoma, urinary bladder transitional cell carcinoma, brain tumours, lung carcinoma, breast adenocarcinoma, leukaemia, Burkitt's lymphoma and endometrial carcinoma.

RESULTS

In colorectal adenocarcinoma, HbF-containing red blood cells (FRBC) were present within thin-walled vessels or were disposed in dense clusters within the tumour. Some of these cells were nucleated or binucleated HbF-erythroblasts or HbF-normoblasts (FNBS). In two cases, high levels of mitoses within HbF-erythroblasts were observed. In half of the cases with transitional cell carcinoma of the urinary bladder, regional intratumoral blood vessels were found to contain 5-50% FRBC. In the other tumours examined, F cells were not observed. FRBCs, however, were occasionally observed in the regional lymph nodes of some of these cancers.

CONCLUSIONS

The evaluation of HbF as a potential plasma marker is suggested by the high concentration of FRBCs in colorectal tumours. The apparent development of FRBCs in colorectal tumour tissues is an interesting observation, as these cells were previously thought to develop in medullary or lymphoid tissues. It is thus suggested that the colonic microenvironment may stimulate extramedullary fetal-type haematopoiesis.

Soy phytochemicals prevent orthotopic growth and metastasis of bladder cancer in mice by alterations of cancer cell proliferation and apoptosis and tumor angiogenesis

A role of dietary bioactive components in bladder cancer prevention is biologically plausible because most substances or metabolites are excreted through the urinary tract and are consequently in direct contact with the mucosa of the bladder. We first determined antigrowth activity of genistein against poorly differentiated 253J B-V human bladder cancer cells in vitro. Genistein inhibited the cell growth in a time- and dose-dependent manner via G(2)-M arrest, down-regulation of nuclear factor kappaB (NF-kappaB), and induction of apoptosis. We also evaluated both genistin, which is a natural form of genistein, and the isoflavone-rich soy phytochemical concentrate (SPC) on the growth and metastasis of 253J B-V tumors in an orthotopic tumor model. Mice treated with genistin and SPC had reduced final tumor weights by 56% (P < 0.05) and 52% (P < 0.05), respectively, associated with induction of tumor cell apoptosis and inhibition of tumor angiogenesis in vivo. In addition, SPC treatment, but not genistin treatment, significantly inhibited lung metastases by 95% (P < 0.01) associated with significant down-regulation of NF-kappaB expression in tumor tissues and reduction of circulating insulin-like growth factor-I levels, suggesting that SPC may contain other bioactive ingredients that have antimetastatic activity. The results from our studies suggest that further clinical investigation should be warranted to apply soy phytochemicals, such as SPC, as a potent prevention regimen for bladder cancer progression. This orthotopic human bladder tumor model also provides a clinically relevant experimental tool for assessing potential preventive activity of other dietary components against bladder tumor growth and metastasis.

Tumour plasticity and extravascular circulation in ECV304 human bladder carcinoma cells

BACKGROUND

The concepts of vasculogenic mimicry and mosaic vessels have been proposed as novel modes of tumour neovascularisation. However, the presence and significance of these types of neovascularisation remain unclear.

MATERIALS AND METHODS

ECV304 human bladder carcinoma cells were used to determine how tumour cells take part in tumour neovascularisation.

RESULTS

Subcutaneous ECV304 xenografts in mice showed various vessel types, including angiogenic vessels, tumour cell-related vessels and extracellular matrix networks. A tracer experiment demonstrated perfusion of beads in these structures. ECV304 cells, cultured on collagen I gels, formed tube networks with expressions of several endothelial-related markers. In coculture models of ECV304 cells and human umbilical vein endothelial cells, the two cells collaborated to form sprouts or networks.

CONCLUSION

ECV304 cells possess an endothelial character which confers the ability to mimic and collaborate with vascular endothelial cells and facilitates the acquisition of tumour microcirculation.

Effect of terazosin on tissue vascularity and apoptosis in transitional cell carcinoma of bladder

OBJECTIVES

To present a pilot study to determine whether the alpha1-adrenoceptor antagonist terazosin can induce apoptosis in transitional cell carcinoma (TCC) of the bladder, similar to the effect seen with prostate cancer. The alpha1-adrenoceptor antagonist terazosin has recently been shown to induce apoptosis in prostate cancer cells both in vitro and in vivo and to reduce prostatic tissue vascularity by potentially affecting endothelial cell adhesion.

METHODS

The records of 24 men who underwent radical cystectomy for TCC of the bladder at the Lexington Veterans Affairs Medical Center were reviewed. The control group consisted of 15 men who were never exposed to terazosin. The study group consisted of 9 men who were treated with terazosin before cystectomy. Sections of the bladder tumor and normal trigone were subjected to immunohistochemical analysis for microvessel density, endothelial cell CD31 expression, and apoptosis detection (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling), as well as high-molecular-weight cytokeratin staining.

RESULTS

A significant reduction in tissue vascularity (14.0 versus 19.2, P <0.05) and a significant increase in the apoptotic index (3.0% versus 1.7%, P <0.05) was detected in terazosin-treated bladder tumors compared with untreated bladder tumors. Most TCC specimens (80%) exhibited strong and consistently uniform immunostaining for high-molecular-weight cytokeratin staining.

CONCLUSIONS

These results suggest that terazosin reduces tumor vascularity and induces apoptosis in TCC of the bladder. Additional studies with more patients are necessary to reach definitive conclusions. However, considering the proven apoptotic action of terazosin in prostatic tissue, this study may have implications for the use of terazosin in the treatment of bladder TCC.

Clinical relevance of serum angiogenic activity in patients with transitional cell carcinoma of the bladder

Angiogenesis is essential for tumor growth and progression and is mediated by positive and negative regulators of vessel growth. Since angiogenic mediators found in patient serum have been postulated to reflect the angiogenic potential of a malignant tumor, we investigated the angiogenic activity in the serum of patients with transitional cell carcinoma (TCC). The data were correlated to tumor characteristics and the clinical course of the patients. Eighty-one patients with transitional cell carcinoma and 53 control persons were included in the study. Preoperative serum samples were collected and both vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were quantified by ELISA. Additionally, the serum evoked proliferative activity on human umbilical vein endothelial cells (HUVEC) was evaluated. Data were compared to the clinical course of the patients. Serum of tumor patients significantly enhanced the proliferative capacity of HUVEC, compared to cells grown in standard culture medium (p = 0.0032), but not when compared to serum from control persons. Serum from patients with superficial TCC and well differentiated tumors induced a significantly higher angiogenic response (ANG(hi)) than serum from patients with poorly differentiated and invasive carcinomas (ANG(lo); p = 0.037). VEGF level of ANG(hi) serum was 384.22 +/- 247.76 pg/ml (n = 37) which significantly differed from mean VEGF level detected in ANG(lo) serum (247.72 +/- 211.93 pg/ml, n = 42; p = 0.019). Similarly, mean bFGF levels were 9.58 +/- 5.91 pg/ml in ANG(hi) serum versus 5.74 +/- 3.52 pg/ml) in ANG(lo) serum (p = 0.0043). A negative correlation was established between VEGF/bFGF serum concentration and patient prognosis. The experiments demonstrate a positive correlation between VEGF and bFGF serum level and endothelial proliferation in vitro. The inverse relationship between angiogenic activity and tumor stage might disclose information about angiogenesis and tumor progression in TCC.

Inhibition of tumor angiogenesis during cisplatin chemotherapy for bladder cancer improves treatment outcome

OBJECTIVES

To investigate the effect of inhibiting tumor angiogenesis during cisplatinum-(II)-diamine dichloride (cisplatin) chemotherapy of bladder cancer (BC) in a rat model.

METHODS

Bladder cancer was induced in 64 male rats using 0.05% N-butyl-N-(4-hydroxybutyl)-nitrosamine in their water supply for 20 weeks. The animals were then divided randomly into four groups of 16 rats each: a control BC group (group 1); a BC group treated with cisplatin (0.25 mg/kg body weight) by intraperitoneal injection twice every week (group 2); a BC group treated with the antiangiogenic factor TNP-470 (30 mg/kg body weight) by intraperitoneal injection twice every week (group 3); and a BC group treated with cisplatin plus TNP-470 (group 4, treatment regimens as described). Per group, 4 rats were killed weekly after the start of treatment, for 4 weeks. BC was confirmed using histologic characteristics, and the treatment outcomes were determined by measuring tumor microvascular density and cell proliferation and apoptosis indexes (PI and AI, respectively).

RESULTS

All animals had confirmed BC. Both group 3 (TNP-470) and group 4 (cisplatin plus TNP-470) had significantly decreased microvascular density compared with group 1 (P <0.05). Although both the PI and AI were significantly different between group 4 (cisplatin plus TNP-470) and group 1 (control BC; P <0.05), neither the PI nor AI was significantly different between group 2 (cisplatin) and group 4 (cisplatin plus TNP-470; P >0.05).

CONCLUSIONS

TNP-470 in conjunction with cisplatin chemotherapy resulted in a decrease in the microvascular density of BC in a rat model. However, TNP-470 did not appear to have a significant impact on the cisplatin effect against BC as measured by apoptosis and cell proliferation.

Vascular endothelial growth factor-C (VEGF-C) expression predicts lymph node metastasis of transitional cell carcinoma of the bladder

PURPOSE

It has been found that expression of vascular endothelial growth factor-C (VEGF-C) in several carcinomas is significantly associated with angiogenesis, lymphangiogenesis and regional lymph node metastasis. However, VEGF-C expression in bladder transitional cell carcinoma (TCC) has not yet been reported. To elucidate the role of VEGF-C in bladder TCC, we examined VEGF-C expression in bladder TCC and pelvic lymph node metastasis specimens obtained from patients who underwent radical cystectomy.

METHODS

Eighty-seven patients who underwent radical cystectomy for clinically organ-confined TCC of the bladder were enrolled in the present study. No neoadjuvant treatments, except transurethral resection of the tumor, were given to these patients. The VEGF-C expressions of 87 bladder tumors and 20 pelvic lymph node metastasis specimens were examined immunohistochemically and the association between VEGF-C expression and clinicopathological factors, including angiogenesis as evaluated by microvessel density (MVD), was also examined.

RESULTS

Vascular endothelial growth factor-C expression was found in the cytoplasm of tumor cells, but not in the normal transitional epithelium. Vascular endothelial growth factor-C expression was significantly associated with the pathological T stage (P = 0.0289), pelvic lymph node metastasis (P < 0.0001), lymphatic involvement (P = 0.0008), venous involvement (P = 0.0002) and high MVD (P = 0.0043). The multivariate analysis demonstrated that VEGF-C expression and high MVD in bladder TCC were independent risk factors influencing the pelvic lymph node metastasis. Moreover, the patients with VEGF-C-positive tumors had significantly poorer prognoses than those with the VEGF-C-negative tumors (P = 0.0087) in the univariate analysis. The multivariate analysis based on Cox proportional hazard model showed that the independent prognostic factors were patient age (P = 0.0132) and pelvic lymph node metastasis (P = 0.0333).

CONCLUSION

The present study suggests that VEGF-C expression is an important predictive factor of pelvic lymph node metastasis in bladder cancer patients.

[Three-dimentional echography in diagnosis and staging of urinary bladder cancer]

The role of USI and three-dimentional volumetric reconstruction was studied in diagnosis of urinary bladder cancer diagnosis. 69 UBC patients were examined. Examination included renal USI of the kidneys, urinary bladder, prostate, echoureterography, cystoscopy, CT, MRT. The number of the tumors, volume, area, invasion were studied in 3D mode. US angiography assessed resistance index and tumor vascularization by degrees 0-3. USI findings were compared with those of MRT, cystoscopy, histomorphology of the biopsies. 2D USI technique proved effective in detection of urinary bladder cancer at stage T1 in 66%, 3D in 100. At stage T2a-b informative value of both techniques reached 87%. Overall informative value of 2D in detection of urinary bladder cancer was 81%, three-dimentional echography--96%. USI proved effective in diagnosis and staging of urinary bladder cancer. Use of 3D ultrasonic angiography facilitates the choice of more effective surgical policy in the treatment of urinary bladder cancer patients.