Cyclooxygenase-2 dependent and independent antitumor effects induced by celecoxib in urinary bladder cancer cells

Bladder cancer, inflammageing and microbiomes

Ageing is correlated with elevated bladder cancer incidence, morbidity and mortality. Advanced age is also associated with elevated markers of chronic inflammation and perturbations in gut and urinary tract microbiota. One reason for the increased incidence and mortality of bladder cancer in the elderly might be that age-associated changes in multiple microbiomes induce systemic metabolic changes that contribute to immune dysregulation with potentially tumorigenic effects. The gut and urinary microbiomes could be dysregulated in bladder cancer, although the effect of these changes is poorly understood. Each of these domains - the immune system, gut microbiome and urinary microbiome - might also influence the response of patients with bladder cancer to treatment. Improved understanding of age-related alterations to the immune system and gut and urinary microbiomes could provide possible insight into the risk of bladder cancer development and progression in the elderly. In patients with bladder cancer, improved understanding of microbiota might also provide potential targets for therapeutic intervention.

Prevention and Treatment of Side Effects of Immunotherapy for Bladder Cancer

Bladder cancer (BC) is one of the most important tumors of the genitourinary system, associated with high morbidity and mortality rates. Over the years, various antitumor treatments have been developed, and immunotherapy is one of the most effective methods. Immunotherapy aims to activate the body’s immune system to kill cancer cells. It has been established that immunotherapy drugs can be classified into “non-targeted” and “targeted” drugs depending on their site of action. Immunotherapy is reportedly effective for BC. Even though it can attack cancer cells, it can also cause the immune system to attack healthy cells, which can occur at any time during treatment and sometimes even after immunotherapy is stopped. Importantly, different types of immunotherapies can cause different side effects. Side effects may manifest themselves as signs or as symptoms. The prevention and treatment of side effects caused by immunotherapy is an important part of cancer patient management.

Prostaglandin E2 as a therapeutic target in bladder cancer: From basic science to clinical trials

Bladder cancer (BCa) is a common solid tumor marked by high rates of recurrence, especially in non-muscle invasive disease. Prostaglandin E₂ (PGE₂) is a ubiquitously present lipid mediator responsible for numerous physiological actions. Inhibition of cyclooxygenase (COX) enzymes by the non-steroidal anti-inflammatory (NSAID) class of drugs results in reduced PGE₂ levels. NSAID usage has been associated with reductions in cancers such as BCa. Clinical trials using NSAIDs to prevent recurrence have had mixed results, but largely converge on issues with cardiotoxicity. The purpose of this review is to understand the basic science behind how and why inhibitors of PGE₂ may be effective against BCa, and to explore alternate therapeutic modalities for addressing the role of PGE₂ without the associated cardiotoxicity. We will address the role of PGE₂ in a diverse array of cancer-related functions including stemness, immunosuppression, proliferation, cellular signaling and more.

NF-κB inhibitor, BAY11-7082, suppresses M2 tumor-associated macrophage induced EMT potential via miR-30a/NF-κB/Snail signaling in bladder cancer cells

BACKGROUND

Chronic inflammatory microenvironment has been shown to play a key role in initiating tumorigenesis and facilitating malignant progression. Primary tumors surrounded with and infiltrated by tumor-associated macrophages (TAMs) significantly promote the epithelial-to-mesenchymal transition (EMT) and distant metastasis in urothelial bladder cancer.

METHODS

In this study, we aimed to explore the potential of targeting TAMs for the treatment of malignant bladder cancer.

RESULTS

First, we found a higher number of TAMs, CD68 (pan-macrophage marker), and clever-1 (M2 macrophage marker) was associated with a higher pT category and grade in a cohort of 108 patients. In vitro assays showed that the co-culture of TAMs promoted the metastatic potential in HTB-1 and T24 by up-regulating EMT markers including Snail, VEGF and Vimentin, as well as oncogenic markers such as β-catenin and NF-κB. More importantly, M2 co-cultured HTB-1 and T24 showed an increased level of metastatic microRNA, miR-30. Silencing of miR-30 resulted in the reduced metastatic potential, migration/invasion, in association with the decreased expression of Twist1 and Vimentin. The addition of BAY11-7082 into the TAM/cancer co-culture system significantly reduced the M2 phenotype and tumorigenic properties. Coincidentally, miR-30a level was significantly lowered in the presence of BAY11-7082.

CONCLUSION

Our study demonstrated that AMs promoted metastatic potential of bladder cancer cells via promoting EMT through the increase of miR-30a. BAY11-7082 treatment suppressed both oncogenic and metastatic potential in bladder cancer cells while preventing the M2 polarization of TAMs.

Cyclooxygenase inhibitors potentiate receptor tyrosine kinase therapies in bladder cancer cells in vitro

Purpose

Receptor tyrosine kinase inhibitors (RTKIs) are used as targeted therapies for patients diagnosed with cancer with highly expressed receptor tyrosine kinases (RTKs), including the platelet-derived growth factor receptor (PDGFR) and c-Kit receptor. Resistance to targeted therapies is partially due to the activation of alternative pro-survival signaling pathways, including cyclooxygenase (COX)-2. In this study, we validated the effects of two RTKIs, axitinib and AB1010, in combination with COX inhibitors on the V-akt murine thymoma oncogene homolog 1 (Akt) and COX-2 signaling pathways in bladder cancer cells.

Methods

The expression of several RTKs and their downstream signaling targets was analyzed by Western blot (WB) analysis in human and canine bladder transitional cell carcinoma (TCC) cell lines. The effects of RTKIs and COX inhibitors in bladder TCC cells were assessed by MTS for cell viability, by Caspase-3/7 and Annexin V assay for apoptosis, by WB analysis for detection of COX-2 and Akt signaling pathways, and by enzyme-linked immunosorbent assay for detection of prostaglandin E2 (PGE₂) levels.

Results

All tested TCC cells expressed the c-Kit and PDGFRα receptors, except human 5637 cells that had low RTKs expression. In addition, all tested cells expressed COX-1, COX-2, Akt, extracellular signal regulated kinases 1/2, and nuclear factor kappa-light-chain-enhance of activated B cells proteins, except human UM-UC-3 cells, where no COX-2 expression was detected by WB analysis. Both RTKIs inhibited cell viability and increased apoptosis in a dose-dependent manner in tested bladder TCC cells, which positively correlated with their expression levels of the PDGFRα and c-Kit receptors. RTKIs increased the expression of COX-2 in h-5637 and K9TCC#1Lillie cells. Co-treatment of indomethacin inhibited AB1010-induced COX-2 expression leading to an additive effect in inhibition of cell viability and PGE₂ production in tested TCC cells.

Conclusion

Co-treatment of RTKIs with indomethacin inhibited cell viability and AB1010-induced COX-2 expression resulting in decreased PGE₂ production in tested TCC cells. Thus, COX inhibition may further potentiate RTKIs therapies in bladder cancer.

Prostaglandin receptors induce urothelial tumourigenesis as well as bladder cancer progression and cisplatin resistance presumably via modulating PTEN expression

Background:

We investigated the role of prostaglandin receptors (e.g. prostaglandin E2 receptor 2 (EP2), EP4) and the efficacy of celecoxib in urothelial tumourigenesis and cancer progression.

Methods:

We performed immunohistochemistry in bladder cancer (BC) tissue microarrays, in vitro transformation assay in a normal urothelial SVHUC line, and western blot/reverse transcription–polymerase chain reaction/cell growth assays in BC lines.

Results:

EP2/EP4 expression was elevated in BCs compared with non-neoplastic urothelial tissues and in BCs from those who were resistant to cisplatin-based neoadjuvant chemotherapy. Strong positivity of EP2/EP4 in non-muscle-invasive tumours or positivity of EP2/EP4 in muscle-invasive tumours strongly correlated with disease progression or disease-specific mortality, respectively. In SVHUC cells, exposure to a chemical carcinogen 3-methylcholanthrene considerably increased and decreased the expression of EP2/EP4 and phosphatase and tensin homologue (PTEN), respectively. Treatment with selective EP2/EP4 antagonist or celecoxib also resulted in prevention in 3-methylcholanthrene-induced neoplastic transformation of SVHUC cells. In BC lines, EP2/EP4 antagonists and celecoxib effectively inhibited cell viability and migration, as well as augmented PTEN expression. Furthermore, these drugs enhanced the cytotoxic activity of cisplatin in BC cells. EP2/EP4 and PTEN were also elevated and reduced, respectively, in cisplatin-resistant BC sublines.

Conclusions:

EP2/EP4 activation correlates with induction of urothelial cancer initiation and outgrowth, as well as chemoresistance, presumably via downregulating PTEN expression.

A Nonselective Cyclooxygenase Inhibitor Enhances the Activity of Vinblastine in a Naturally-Occurring Canine Model of Invasive Urothelial Carcinoma

Background: Chemotherapy is expected to remain an important part of invasive urothelial carcinoma (UC) treatment. Strategies to enhance chemotherapy efficacy are needed.

Objective: To determine the chemotherapy-enhancing effects of a nonselective cyclooxygenase (COX) inhibitor on vinblastine in a naturally-occurring canine model of invasive UC.

Methods: With IACUC approval, privately-owned dogs with naturally-occurring histologically-diagnosed invasive UC, expected survival ≥6 weeks, and informed owner consent were randomly allocated to receive vinblastine (2.5 mg/m² intravenously every 2 weeks) plus piroxicam (0.3 mg/kg daily per os) or vinblastine alone (same dose) with the option to receive piroxicam alone when vinblastine failed. Scheduled evaluations included physical exam, standard laboratory analyses, thoracic radiography, abdominal ultrasonography, and standardized measurement of urinary tract tumors.

Results: Dogs receiving vinblastine alone (n = 27) and vinblastine-piroxicam (n = 24) were similar in age, sex, breed, tumor stage, and grade. Remission occurred more frequently (P <  0.02) with vinblastine-piroxicam (58.3%) than with vinblastine alone (22.2%). The median progression free interval was 143 days with vinblastine alone and 199 days with the combination. Interestingly, the overall median survival time was significantly longer (P <  0.03) in dogs receiving vinblastine alone followed by piroxicam alone (n = 20, 531 days) than in dogs receiving the combination (299 days). Treatment was well tolerated in both arms.

Conclusions: Piroxicam significantly enhanced the activity of vinblastine in dogs with UC where the cancer closely mimics the human condition, clearly justifying further study. The study suggest the potential importance of tracking COX inhibitor use in patients in clinical trials as COX inhibitors could affect treatment response.

The interplay between GRP78 expression and Akt activation in human colon cancer cells under celecoxib treatment

It has been reported previously that celecoxib shows antitumor effects in many types of cancers. Here, we detected its effects on DLD-1 and SW480 (two human colon cancer cell lines) and investigated the dynamic relationship between the 78-kDa glucose-regulatory protein (GRP78) and the phosphoinositide 3-kinase (PI3K)/Akt pathway. Gene expression was detected by real-time PCR and western blot analysis; the cytotoxicity was determined by the MTT assay and flow cytometry. First, the results showed that celecoxib induced cytotoxicity in a dose-dependent and time-dependent manner. Furthermore, we found the celecoxib-triggered unfolded protein response and the bidirectional regulation of Akt activation in both cell lines. Inhibiting the Akt activation by the PI3K inhibitor LY294002 markedly enhanced GRP78 expression. Besides, silencing the GRP78 expression regulated Akt activation in a time-dependent manner and increased the induction of the C/EBP homologous protein (CHOP) as well as considerably promoted celecoxib-induced apoptosis. In conclusion, these findings provide evidence that under the celecoxib treatment, GRP78 plays a protective role by modulating Akt activation and abrogating CHOP expression. However, Akt activation can provide a feedback loop to inhibit GRP78 expression. These studies can lead to novel therapeutic strategies for human colon cancer.

Positive selection of Wharton's jelly-derived CD105(+) cells by MACS technique and their subsequent cultivation under suspension culture condition: A simple, versatile culturing method to enhance the multipotentiality of mesenchymal stem cells

OBJECTIVE

Wharton's jelly (WJ), an appropriate source of mesenchymal stem cells (MSCs), has been shown to have a wide array of therapeutic applications. However, the WJ-derived MSCs are very heterogeneous and have limited expression of pluripotency markers. Hence, improvement of their culture condition would promote the efficiency of WJ-MSCs. This study aims to employ a simple method of cultivation to obtain WJ-MSCs which express more pluripotency markers.

METHODS

CD105(+) cells were separated by magnetic-associated (activated) cell sorting from umbilical cord mucous tissue. CD105(+) cells were added to Methocult medium diluted in α-minimum essential medium (α-MEM) and seeded in poly(2-hydroxyethyl methacrylate) (poly-HEMA)-coated plates for suspension culture preparation. Differentiation capacity of isolated cells was evaluated in the presence of differentiation-inducing media. The expression of pluripotency markers such as Oct3/4, Nanog, and Sox2 was also analyzed by RT-PCR and western blot techniques. Moreover, immunocytochemistry was performed to detect alpha-smooth muscle actin (antigene) (α-SMA) protein.

RESULTS

WJ-MSCs grew homogeneously and formed colonies when cultured under suspension culture conditions (Non-adhesive WJ-MSCs). They maintained their growth ability in both adherent and suspension cultures for several passages. Non-adhesive WJ-MSCs expressed Oct3/4, Nanog, and Sox2 both at transcriptional and translational levels in comparison to those cultured in conventional adherent cultures. They also expressed α-SMA protein.

DISCUSSION

In this study, we isolated WJ-MSCs using a slightly modified culture condition. Our simple non-genetic method resulted in a homogeneous population of WJ-MSCs, which highly expressed pluripotency markers.

CONCLUSION

In the future, more multipotent WJ-MSCs can be harnessed as a non-embryonic source of MSCs in MSC-based cell therapy.

Differences in Expression of Uroplakin III, Cytokeratin 7, and Cyclooxygenase-2 in Canine Proliferative Urothelial Lesions of the Urinary Bladder

The expression of immunohistochemical markers that have been used in diagnosis and/or prognostication of urothelial tumors in humans (uroplakin III [UPIII], cytokeratin 7 [CK7], cyclooxygenase-2 [COX-2], and activated caspase 3) was evaluated in a series of 99 canine proliferative urothelial lesions of the urinary bladder and compared to the lesion classification and grade as defined by the World Health Organization / International Society of Urologic Pathology consensus system. There were significant associations between tumor classification and overall UPIII pattern ( P = 1.49 × 10–18), loss of UPIII ( P = 1.27 × 10–4), overall CK7 pattern ( P = 4.34 × 10–18), and COX-2 pattern ( P = 8.12 × 10–25). In addition, there were significant associations between depth of neoplastic cell infiltration into the urinary bladder wall and overall UPIII pattern ( P = 1.54 × 10–14), loss of UPIII ( P = 2.07 × 10–4), overall CK7 pattern ( P = 1.17 × 10–13), loss of CK7 expression ( P = .0485), and COX-2 pattern ( P = 8.23 × 10–21). There were no significant associations between tumor classification or infiltration and caspase 3 expression pattern.

Celecoxib-induced cytotoxic effect is potentiated by inhibition of autophagy in human urothelial carcinoma cells

Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, can elicit anti-tumor effects in various malignancies. Here, we sought to clarify the role of autophagy in celecoxib-induced cytotoxicity in human urothelial carcinoma (UC) cells. The results shows celecoxib induced cellular stress response such as endoplasmic reticulum (ER) stress, phosopho-SAPK/JNK, and phosopho-c-Jun as well as autophagosome formation in UC cells. Inhibition of autophagy by 3-methyladenine (3-MA), bafilomycin A1 or ATG7 knockdown potentiated celecoxib-induced apoptosis. Up-regulation of autophagy by rapamycin or GFP-LC3B-transfection alleviated celecoxib-induced cytotoxicity in UC cells. Taken together, the inhibition of autophagy enhances therapeutic efficacy of celecoxib in UC cells, suggesting a novel therapeutic strategy against UC.

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin inhibits epidermal growth factor receptor signaling pathway activation and induces apoptosis in bladder cancer cells in vitro and in vivo

OBJECTIVES

Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PA-MSHA), a peritrichous P. aeruginosa strain with MSHA fimbriae, has been shown to be a valuable anticancer drug in many kinds of cancers. However, the effect of PA-MSHA on bladder cancer has not been elucidated. In this study, we focused on the antitumor activities and related mechanisms of PA-MSHA on bladder cancer in vitro and in vivo.

MATERIALS AND METHODS

SV-40-immortalized normal uroepithelial cells (SV-HUC-1) and human bladder cancer cell lines (T24, 5637, and HT-1376) were treated with PA-MSHA or PA (heat-killed P. aeruginosa). At first, the effect of PA-MSHA on cancer cell proliferation was measured using Cell Counting Assay Kit-8 (CCK-8), whereas the changes of cell morphology were observed by transmission electron microscopy. The early apoptosis induced by PA-MSHA was evaluated by flow cytometry, and the expression level of apoptosis-related molecules was detected using Western blot assay. We then investigated the activation of the epidermal growth factor receptor signaling pathway stimulated by PA-MSHA; the expression and phosphorylation of several key regulators involved in the EGFR signaling pathway were detected. At last, xenograft tumor in nude mice was used to further investigate the antitumor effect of PA-MSHA in vivo.

RESULTS

Our results showed that PA-MSHA could efficiently inhibit proliferation and induce apoptosis in human bladder cancer cell lines. Furthermore, cells stimulated with PA-MSHA exhibited an inactivation of EGFR signaling. In vivo, PA-MSHA treatment significantly suppressed tumor growth and induced apoptosis in xenografts tumor in nude mice.

CONCLUSIONS

PA-MSHA could efficiently inhibit proliferation and induce apoptosis in human bladder cancer cells in vitro and in vivo, which is associated with the inactivation of EGFR signaling pathway, and it might be used as a potential therapeutic agent for bladder cancer.

Down-regulation of glucose-regulated protein (GRP) 78 potentiates cytotoxic effect of celecoxib in human urothelial carcinoma cells

Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor that has been reported to elicit anti-proliferative response in various tumors. In this study, we aim to investigate the antitumor effect of celecoxib on urothelial carcinoma (UC) cells and the role endoplasmic reticulum (ER) stress plays in celecoxib-induced cytotoxicity. The cytotoxic effects were measured by MTT assay and flow cytometry. The cell cycle progression and ER stress-associated molecules were examined by Western blot and flow cytometry. Moreover, the cytotoxic effects of celecoxib combined with glucose-regulated protein (GRP) 78 knockdown (siRNA), (−)-epigallocatechin gallate (EGCG) or MG132 were assessed. We demonstrated that celecoxib markedly reduces the cell viability and causes apoptosis in human UC cells through cell cycle G1 arrest. Celecoxib possessed the ability to activate ER stress-related chaperones (IRE-1α and GRP78), caspase-4, and CCAAT/enhancer binding protein homologous protein (CHOP), which were involved in UC cell apoptosis. Down-regulation of GRP78 by siRNA, co-treatment with EGCG (a GRP78 inhibitor) or with MG132 (a proteasome inhibitor) could enhance celecoxib-induced apoptosis. We concluded that celecoxib induces cell cycle G1 arrest, ER stress, and eventually apoptosis in human UC cells. The down-regulation of ER chaperone GRP78 by siRNA, EGCG, or proteosome inhibitor potentiated the cytotoxicity of celecoxib in UC cells. These findings provide a new treatment strategy against UC.

Cyclooxygenase inhibitors: scope of their use and development in cancer chemotherapy

The traditional nonsteroidal anti-inflammatory drugs (NSAIDs) exert their effect by inhibition of cyclooxygenase-1 (COX-1) as well as COX-2 enzymes. As COX-1 is responsible for maintaining normal biological functions, the nonselective inhibition of these enzymes caused side effects including gastrointestinal (GI) problems. Recently developed selective COX-2 inhibitors could reduce these adverse effects, but the evidence of cardiovascular side effects including an increased risk of myocardial infarction began to emerge, and some of the COX-2 inhibitors were eventually withdrawn from the market and this led to the downfall of this research. So, the discovery of novel COX-2 inhibitors with their safety profile became the biggest challenge in pharmaceutical research. However, recent mechanistic and clinical studies revolutionized this area by indicating the fact that COX-2 is involved in apoptosis resistance, angiogenesis, and tumor progression. Epidemiological data suggest that selective COX-2 inhibitors might prevent the development of cancers. Moreover, COX-2 is found to be overexpressed in many cancers thus making it an attractive therapeutic target for the prevention and treatment of a number of malignancies. The purpose of this review is to focus on the medicinal chemistry aspects of COX-2 inhibitors in cancer chemotherapy and recent reports on these inhibitors as anticancer agents. We attempted to cover only the COX inhibitors that showed anticancer activity, although a number of potent COX-2 inhibitors have been reported without their anticancer effects. Furthermore, structure-activity relationships (SAR) of different classes of compounds for COX-2 inhibition as well as anticancer activity, and their future applications are discussed.

Effect of liposomal celecoxib on proliferation of colon cancer cell and inhibition of DMBA-induced tumor in rat model

Celecoxib, a selective cyclooxygenase-2 inhibitor, has shown potential anticancerous activity against majority of solid tumors especially on patients with colon cancer. However, associations of serious side effects limit the usage of celecoxib in colon cancer treatment. To address this issue and provide an alternative strategy to increase the efficacy of celecoxib, liposomal formulation of celecoxib was prepared and characterized. Anticancer activity of liposomal celecoxib on colon cancer cell HCT 15 was evaluated in vitro. Furthermore, tumor inhibition efficiency by liposomal celecoxib was studied on 7,12-dimethyl benz(a)anthracene (DMBA)-induced tumor in rat model. In order to elucidate the antioxidant activity of celecoxib-loaded liposomes, antioxidant superoxide dismutase (SOD) generation and lipid peroxide (LPx) formation in both liver and kidney tissues were examined. Characterization of the formed unilamellar liposomes revealed the formation of homogeneous suspension of neutral (empty) or anionic (celecoxib-loaded) liposomes with a well-defined spherical shape which have a mean size of 103.5 nm (empty liposome) and 169 nm (liposomal celecoxib). High-performance liquid chromatography (HPLC) analysis and hemolytic assay demonstrated 46% of celecoxib entrapment efficiency and significantly low hemolysis, respectively. Liposomal celecoxib exhibited dose-dependent cytotoxicity and apoptotic activity against HCT 15 cells which are comparable to free celecoxib. In vivo study demonstrated inhibition of tumor growth. Biochemical analysis of the liposomal celecoxib-treated group significantly inhibited the LPx formation (oxygen-free radicals) and increased the activity of SOD. Our results present the potential of inhibiting colon cancer in vitro and DMBA-induced tumor in rat model in vivo by liposomal celecoxib.

Leaf Extracts of Calocedrus formosana (Florin) Induce G2/M Cell Cycle Arrest and Apoptosis in Human Bladder Cancer Cells

Calocedrus formosana (Florin) bark acetone/ethylacetate extracts are known to exert an antitumor effect on some human cancer cell lines, but the mechanism is yet to be defined. The aim of this study was to determine the effects of Florin leaf methanol extracts on the growth and apoptosis of human bladder cancer cell lines. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that the growth of these bladder cancer cells was potently inhibited by the Florin leaf extracts. The cell cycle of these extract-treated cells (TCCSUP cells) was arrested at the G2/M phase as determined by flow cytometry. Western blot analysis revealed the increases of cyclin B1 and Cdc2 kinase levels, alone with the decrease of phosphorylated Cdc2 kinase, after treating these cells with the extracts. An immunofluorescence assessment of β-tubulin showed decreased levels of polymerized tubulin in treated cells. However, the proteolytic cleavage of poly ADP-ribose polymerase and the activation of caspase-3/-8/-9 were all increased upon treatments of extracts. The concurrent increase of Bax and decrease of Bcl-2 levels indicated that the extracts could induce apoptosis in these treated cells. Taken together, these results suggest that the Florin leaf extracts may be an effective antibladder cancer agent.

Improved cancer specific-survival in patients with carcinoma invading bladder muscle expressing cyclo-oxygenase-2

Study Type - Prognosis (case series).

LEVEL OF EVIDENCE

4 OBJECTIVE: To determine whether the expression of cyclo-oxygenase (COX)-2 has an influence on survival and on the response to chemotherapy in invasive bladder cancer.

PATIENTS AND METHODS

A population of 266 patients from a tertiary university centre with carcinoma invading bladder muscle without evidence of metastasis at time of cystectomy was analyzed retrospectively. COX-2 expression was evaluated immunohistochemically with a monoclonal anti-COX-2 antibody. All pertinent clinical and pathological parameters were reviewed and correlated with risk factors influencing outcome, including disease-specific and overall survival, as well as COX-2 expression. Immunoreactivity was categorized as positive if COX-2 staining was present in >5% tumour cells.

RESULTS

The expression of COX-2 was not influenced by tumour stage, grade or nodal status, nor any other parameters. The risk factors that influenced disease-specific survival in carcinoma invading bladder muscle on multivariate analysis were lymph node status (hazards ratio, HR = 2.46 for N1, P = 0.001, HR = 2.90 for N2, P < 0.001, HR = 5.19 for N3, P = 0.012), use of neoadjuvant chemotherapy (HR = 3.54; P= 0.004) or adjuvant chemotherapy (HR = 0.57, P = 0.014) and COX-2 expression (HR = 0.64 if >5% cells had positive expression; P = 0.025). Kaplan-Meier analysis showed an increased disease-specific survival (P = 0.0063), as well as longer recurrence-free survival (P = 0.003), in patients with muscle-invasive bladder tumours expressing COX-2 in >5% of the cells. A tendency was also observed in a subgroup with positive nodes treated with adjuvant chemotherapy (P = 0.093).

CONCLUSIONS

The overexpression of COX-2 is associated with a better recurrence-free and disease-specific survival in a large cohort of 266 patients with carcinoma invading bladder muscle treated by cystectomy. A trend for increased disease-specific survival was also observed for patients with COX-2 overexpression and positive nodes who received adjuvant chemotherapy. Potential of COX-2 as a prognostic marker in bladder cancer should be considered.

Preclinical evaluation of a gene therapy treatment for transitional cell carcinoma

Three drugs were compared for their efficacy in treating murine transitional cell carcinoma (TCC) of the bladder. Intravesical gene therapy treatments utilizing expression-targeted plasmids, where the murine cyclooxygenase-2 (Cox-2) promoter was used to drive the expression of exogenously inducible forms of caspases 3 and 9, were compared with treatment modalities employing Bacille Calmette-Guérin (BCG) and celecoxib. When administered via lavage, only the gene therapy regimen was found to be effective at restricting tumor progression following a 7-day incubation of tumor tissues. Celecoxib was also administered via the diet to allow for systemic delivery of the drug. The most efficacious celecoxib use tested yielded tumors with masses of (18.3±8.4 mg) versus the gene delivery method, which yielded tumors with masses of (3.6±7.7 mg). The difference was significant (t-test, n≥4, P<0.025). The results showed that the Cox-2 expression-targeted gene therapy system could efficiently bypass the bladder permeability barrier and more effectively inhibit tumor growth and development than either BCG or celecoxib treatments. Long-term data further demonstrated that the gene therapy system could effectively inhibit tumor growth and elongate life expectancy.

Induction of VEGF by tepoxalin does not lead to increased tumour growth in a canine osteosarcoma xenograft

The purpose of this study was to determine the impact of the non-steroidal anti-inflammatory drug tepoxalin on canine tumour cell growth and describe the changes associated with tepoxalin treatment. In vitro experiments were performed to assess tepoxalin-associated alterations in tumour cell growth. Clinically achievable tepoxalin concentrations did not significantly alter tumour cell growth in vitro. Vascular endothelial growth factor (VEGF) production and hypoxia-inducible factor-1α dose-dependently increased in vitro in the presence of tepoxalin. A canine osteosarcoma xenograft was used to determine in vivo effects of tepoxalin on tumour growth and angiogenesis. Despite increased VEGF in vitro, there was a significant growth delay associated with tepoxalin treatment. Normal dogs were administered tepoxalin to assess effects on systemic VEGF production, but not found to have significantly increased VEGF. These data suggest that tepoxalin may moderately inhibit tumour growth and may be administered as an analgesic to tumour-bearing dogs.

Effects of short-term celecoxib treatment in patients with invasive transitional cell carcinoma of the urinary bladder

High-grade invasive transitional cell carcinoma (InvTCC) kills >14,000 people yearly in the United States, and better therapy is needed. Cyclooxygenase-2 (Cox-2) is overexpressed in bladder cancer. Cox inhibitors have caused remission of InvTCC in animal studies, and cancer regression was associated with doubling of the apoptotic index in the tumor. The purpose of this study was to determine the apoptosis-inducing effects of celecoxib (a Cox-2 inhibitor) in InvTCC in humans. Patients (minimum of 10 with paired tumor samples) with InvTCC who had elected to undergo cystectomy were enrolled. The main study end point was induction of apoptosis in tumor tissues. Patients received celecoxib (400 mg twice daily p.o. for a minimum of 14 days) between the time of diagnosis [transurethral resection of bladder tumor (TURBT)] and the time of cystectomy (standard frontline treatment for InvTCC). Terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling assay and immunohistochemistry were done on TURBT and cystectomy samples. Of 13 cases treated with celecoxib, no residual invasive cancer was identified in 3 patients at the time of cystectomy (post celecoxib). Of the 10 patients with residual cancer, 7 had induction of apoptosis in their tumor. Induction of apoptosis was less frequent (3 of 13 cases; P < 0.04) in control patients not receiving a Cox inhibitor. Expression of vascular endothelial growth factor in the tumor cells decreased more frequently (P < 0.026) in the treated patients as compared with nontreated control cases. The biological effects of celecoxib treatment (increased apoptosis) justify further study of the antitumor effects of Cox-2 inhibitors in InvTCC.

Cyclooxygenase-2 expression on urothelial and inflammatory cells of cystoscopic biopsies and urine cytology as a possible predictive marker for bladder carcinoma

Cyclooxygenase-2 (COX-2) is a key inducible enzyme involved in the production of prostaglandins. It contributes to human carcinogenesis by various mechanisms. The aim of the current study was to elucidate the possible involvement of COX-2 in human bladder carcinoma by examining its expression on both urothelial and inflammatory cells in tissue biopsies and urine cytology samples of different urinary bladder lesions. A total of 65 patients were included in the study and were selected from cases admitted to Urology Department, Theodor Bilharz Research Institute (TBRI), Giza, Egypt. They represented seven control cases with almost normal-looking bladder tissue; pure chronic cystitis (n=12); premalignant lesions (18) in the form of squamous metaplasia (n=8) or urothelial dysplasia (n=10) as well as transitional cell carcinoma (TCC) (n=18), and squamous cell carcinoma (SqCC) (n=10). Immunohistochemistry of formalin-fixed, paraffin-embedded tissue sections and urine cytology samples was performed for all cases using COX-2 (H-62): sc-7951, a rabbit polyclonal antibody. The study revealed positive COX-2 expression on the urothelial and inflammatory cells of cystoscopic biopsies from all cases of pure chronic cystitis, squamous metaplasia and SqCC compared with 42.8% and 71.4% of normal controls, respectively. The score of urothelial COX-2 expression was sequentially up-regulated from normal to chronic cystitis (either pure or associated with premalignant changes) (p<0.05) to malignant changes (p<0.05). However, the inflammatory cellular expression was down-regulated with malignant transformation compared with chronic cystitis (p<0.05). In TCC, COX-2 was over-expressed on both urothelial and inflammatory cells in advanced tumors. Urine cytology samples were positive for COX-2 in a comparable manner to that observed in cystoscopic biopsies. Accordingly, the results of the current study have provided new information in two aspects: First, is the possibility of using the differential COX-2 expression on both inflammatory and urothelial cells as markers for premalignant or malignant transformation; second, besides cystoscopy, urine cytology was found to have a high sensitivity for COX-2 expression and hence proved to be valuable in malignancy as a non-invasive substitute for cystoscopy.

Endocavitary Prophylaxis of Superficial Urothelial Bladder Tumours: New Compounds

Bladder urothelial carcinoma is the fourth most frequent cancer among European men, accounting for about 7% of the total cancers. Transurethral resection (TUR) is usually indicated as the standard treatment for non-muscle invasive bladder cancer (NMIBC). However, TUR is unable to guarantee a complete eradication of Ta, T1 tumors with a recurrence rate ranging from 50 to 70%, and a progression rate to muscle invasive disease ranging from 10 to 15%.

Methods

The European Association of Urology guidelines recommend adjuvant intravesical chemotherapy after definitive diagnosis of intermediate/high risk NMIBC to reduce both recurrence and progression of the disease. To provide a comprehensive review of intravesical treatment options for NMIBC, we performed a search of the PubMed database for articles between 1980 and 2009 that reported on intravesical agents for treating this disease.

Results

A critical analysis of the findings resulting from large multicenter trials, phase I, II, III studies for pertinent novel agents and from review articles was carried out. We focused on the following issues: 1) the role of the treatment with Bacillus Calmette-Guérin (BCG) and the need of maintaining the drug schedule (with or without interferon-alpha); 2) the correct timing of adjuvant immuno- and chemotherapy; 3) the use of the novel chemotherapeutic agents; 4) the use of the novel technique of chemotherapeutic agents administration, with a particular interest on electromotive administration of mitomycin.