Enhanced expression of cyclooxygenase-2 in high grade human transitional cell bladder carcinomas

Integrated network pharmacology and RNA sequencing analysis to reveal the mechanisms of Qici Sanling decoction in the treatment of gemcitabine resistant bladder cancer

Bladder cancer (BCa) is the most prevalent cancer of the urinary system in adults; the prognosis is dismal for BCa treated with gemcitabine (GEM) owing to intrinsic or acquired chemoresistance. This study investigated the potential of Qici Sanling decoction (QCSL), an herbal Chinese medicine, to augment the efficacy of GEM in treating GEM-resistant BCa via network pharmacology and RNA sequencing. We screened 103 active components of QCSL and their 226 targets from the TCMSP database and identified 3985 targets of GEM-resistant BCa via transcriptome sequencing. On the basis of the 69 common targets, a proteinprotein interaction (PPI) network was constructed to identify the top 7 targets. Disease Ontology (DO), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analyses were conducted to uncover key pathways. CCK-8 assays, Western blotting, flow cytometry, colony formation, and EdU assays were used to assess the apoptosis and proliferation of GEM-resistant T24 and J82 cells treated with QCSL. The BCa gene set was among the top enriched gene sets in the DO analysis; GO analysis revealed enrichment of 2020 terms linked to GEM resistance, and KEGG analysis revealed 161 enriched signalling pathways. Molecular docking indicated that PTGS2 has high affinity for targets of QCSL components. In vitro experiments demonstrated that cells treated with both QCSL and GEM had significantly reduced viability, increased levels of apoptosis, and decreased proliferative capacity. Thus, QCSL enhances the therapeutic effects of GEM in BCa by promoting cell apoptosis and inhibiting cell proliferation. These findings have significant clinical implications, highlighting a potential combined treatment strategy for GEM-resistant BCa to improve patient outcomes.

A conditionally replicative adenovirus vector containing the synNotch receptor gene for the treatment of muscle-invasive bladder cancer

Muscle-invasive bladder cancer (MIBC), a highly heterogeneous disease, shows genomic instability and a high mutation rate, making it difficult to treat. Recent studies revealed that cancer stem cells (CSCs) play a critical role in MIBC frequent recurrence and high morbidity. Previous research has shown that Cyclooxygenases-2 (COX-2) is particularly highly expressed in bladder cancer cells. In recent years, the development of oncolytic adenoviruses and their use in clinical trials have gained increased attention. In this study, we composed a conditionally replicative adenovirus vector (CRAd-synNotch) that carries the COX-2 promotor driving adenoviral E1 gene, the synNotch receptor therapeutic gene, and the Ad5/35 fiber gene. Activation of the COX-2 promoter gene causes replication only within COX-2 expressing cancer cells, thereby leading to tumor oncolysis. Also, CD44 and HIF signals contribute to cancer stemness and maintaining CSCs in bladder cancer, and the transduced synNotch receptor inhibits both CD44 and HIF signals simultaneously. We performed an in vivo study using a mouse xenograft model of T24 human MIBC cells and confirmed the significant antitumor activity of CRAd-synNotch. Our findings in this study warrant the further development of CRAd-synNotch for treating patients with MIBC.

DNA Polymerase Theta Plays a Critical Role in Pancreatic Cancer Development and Metastasis

Pancreatic ductal adenocarcinoma (PDAC), due to its genomic heterogeneity and lack of effective treatment, despite decades of intensive research, will become the second leading cause of cancer-related deaths by 2030. Step-wise acquisition of mutations, due to genomic instability, is considered to drive the development of PDAC; the KRAS mutation occurs in 95 to 100% of human PDAC, and is already detectable in early premalignant lesions designated as pancreatic intraepithelial neoplasia (PanIN). This mutation is possibly the key event leading to genomic instability and PDAC development. Our study aimed to investigate the role of the error-prone DNA double-strand breaks (DSBs) repair pathway, alt-EJ, in the presence of the KRAS G12D mutation in pancreatic cancer development. Our findings show that oncogenic KRAS contributes to increasing the expression of Polθ, Lig3, and Mre11, key components of alt-EJ in both mouse and human PDAC models. We further confirm increased catalytic activity of alt-EJ in a mouse and human model of PDAC bearing the KRAS G12D mutation. Subsequently, we focused on estimating the impact of alt-EJ inactivation by polymerase theta (Polθ) deletion on pancreatic cancer development, and survival in genetically engineered mouse models (GEMMs) and cancer patients. Here, we show that even though Polθ deficiency does not fully prevent the development of pancreatic cancer, it significantly delays the onset of PanIN formation, prolongs the overall survival of experimental mice, and correlates with the overall survival of pancreatic cancer patients in the TCGA database. Our study clearly demonstrates the role of alt-EJ in the development of PDAC, and alt-EJ may be an attractive therapeutic target for pancreatic cancer patients.

Antiproliferative and apoptotic activity of gemcitabine-lauric acid conjugate on human bladder cancer cells

Objectives

Gemcitabine is a first-line drug for the treatment of bladder cancer. One of the most important mechanisms of gemcitabine resistance is the low expression of cellular membrane transporter hENT1. Various derivatives containing fatty acid side chains have been developed in order to facilitate gemcitabine uptake and prolong its retention in cells, such as CP-4126. In this study, the anti-tumor effect and mechanism of a new derivative of gemcitabine named SZY-200 on bladder cancer cells were investigated. SZY-200 was assembled from the gemcitabine-lauric acid conjugate.

Materials and Methods

Antiproliferative activities of SZY-200 and lauric acid were evaluated using CCK-8 assay and clonogenic survival assay. The hENT1 inhibitor NBMPR was employed to determine the role of hENT1 in the apoptotic activity of GEM, CP-4126, and SZY-200. RT-qPCR, flow cytometry, fluorescence microscope, western blotting, and wound healing assay were used to study the mechanisms of SZY-200. The target genes were predicted using the BATMAN-TCM database.

Results

Our data showed that SZY-200 could inhibit the proliferation of bladder cancer cells by inducing cell cycle arrest and apoptosis. The inhibitory effects were comparable to gemcitabine and CP-4126. SZY-200 does not rely on hENT1 to help it enter bladder cancer cells. Also, we found that lauric acid could inhibit the proliferation of bladder cancer cells. SZY-200 could down-regulate the expressions of PPARG and PTGS2 which were related to the occurrence and development of bladder cancer.

Conclusion

SZY-200 has the same or more advantages as CP-4126 and could be an ideal candidate drug for further in vivo investigation.

Gut-Restricted Selective Cyclooxygenase-2 (COX-2) Inhibitors for Chemoprevention of Colorectal Cancer

Selective cyclooxygenase (COX)-2 inhibitors have been extensively studied for colorectal cancer (CRC) chemoprevention. Celecoxib has been reported to reduce the incidence of colorectal adenomas and CRC but is also associated with an increased risk of cardiovascular events. Here, we report a series of gut-restricted, selective COX-2 inhibitors characterized by high colonic exposure and minimized systemic exposure. By establishing acute ex vivo ¹⁸F-FDG uptake attenuation as an efficacy proxy, we identified a subset of analogues that demonstrated statistically significant in vivo dose-dependent inhibition of adenoma progression and survival extension in an APC^min/+ mouse model. However, in vitro-in vivo correlation analysis showed their chemoprotective effects were driven by residual systemic COX-2 inhibition, rationalizing their less than expected efficacies and highlighting the challenges associated with COX-2-mediated CRC disease chemoprevention.

Detection of carcinogen-induced bladder cancer by fluorocoxib A

BACKGROUND

Conventional cystoscopy can detect advanced stages of bladder cancer; however, it has limitations to detect bladder cancer at the early stages. Fluorocoxib A, a rhodamine-conjugated analog of indomethacin, is a novel fluorescent imaging agent that selectively targets cyclooxygenase-2 (COX-2)-expressing cancers.

METHODS

In this study, we have used a carcinogen N-butyl-N-4-hydroxybutyl nitrosamine (BBN)-induced bladder cancer immunocompetent mouse B6D2F1 model that resembles human high-grade invasive urothelial carcinoma. We evaluated the ability of fluorocoxib A to detect the progression of carcinogen-induced bladder cancer in mice. Fluorocoxib A uptake by bladder tumors was detected ex vivo using IVIS optical imaging system and Cox-2 expression was confirmed by immunohistochemistry and western blotting analysis. After ex vivo imaging, the progression of bladder carcinogenesis from normal urothelium to hyperplasia, carcinoma-in-situ and carcinoma with increased Ki67 and decreased uroplakin-1A expression was confirmed by histology and immunohistochemistry analysis.

RESULTS

The specific uptake of fluorocoxib A correlated with increased Cox-2 expression in progressing bladder cancer. In conclusion, fluorocoxib A detected the progression of bladder carcinogenesis in a mouse model with selective uptake in Cox-2-expressing bladder hyperplasia, CIS and carcinoma by 4- and 8-fold, respectively, as compared to normal bladder urothelium, where no fluorocoxib A was detected.

CONCLUSIONS

Fluorocoxib A is a targeted optical imaging agent that could be applied for the detection of Cox-2 expressing human bladder cancer.

Detection of tyrosine kinase inhibitors-induced COX-2 expression in bladder cancer by fluorocoxib A

Among challenges of targeted therapies is the activation of alternative pro-survival signaling pathways in cancer cells, resulting in an acquired drug resistance. Cyclooxygenase-2 (COX-2) is overexpressed in bladder cancer cells, making it an attractive molecular target for the detection and treatment of cancer. Fluorocoxib A is an optical imaging agent that selectively targets COX-2. In this study, we evaluated the ability of fluorocoxib A to monitor the responses of bladder cancer to targeted therapies in vivo. The effects of several tyrosine kinase inhibitors (TKIs: axitinib, AB1010, toceranib, imatinib, erlotinib, gefitinib, imatinib, sorafenib, vandetanib, SP600125, UO126, and AZD 5438) on COX-2 expression were validated in ten human and canine bladder cancer cell lines (J82, RT4, T24, UM-UC-3, 5637, SW780, TCCSUP, K9TCC#1Lillie, K9TCC#2Dakota, K9TCC#5Lilly) in vitro. The effects of TKIs on bladder cancer in vivo were evaluated using the COX-2-expressing K9TCC#5Lilly xenograft mouse model and detected by fluorocoxib A. The increased COX-2 expression was detected by all tested TKIs in at least one of the tested COX-2-expressing bladder cancer cell lines (5637, SW780, TCCSUP, K9TCC#1Lillie, K9TCC#2Dakota, and K9TCC#5Lilly) in vitro. In addition, fluorocoxib A uptake correlated with the AB1010- and imatinib-induced COX-2 expression in the K9TCC#5Lilly xenografts in vivo. In conclusion, these results indicate that fluorocoxib A could be used for the monitoring the early responses to targeted therapies in COX-2-expressing bladder cancer.

Association of Cyclooxygenase-2 Immunoreactivity with Tumor Recurrence and Disease Progression in Superficial Urothelial Bladder Cancer

Aims and Background

The main characteristic of urothelial bladder cancer is a clear predisposition to recurrence and disease progression. The aim of this study was to assess the possible relationship between cyclooxygenase-2 (COX-2) immunoreactivity in superficial urothelial bladder carcinoma and tumor grade, stage, number of recurrences and clinical disease progression.

Methods

In this prospective study 70 consecutive patients who underwent transurethral resection for superficial urothelial bladder cancer were included. Tumor slides were immuno-histochemically stained for COX-2, and COX-2 immunoreactivity in tumor and inflammatory stromal cells was categorized as negative or mildly, moderately or strongly positive. Patients were followed up for 2 years, and during this period the possible association of COX-2 immunoreactivity with tumor stage and grade, number of recurrences and progression of disease was evaluated.

Results

COX-2 immunoreactivity in tumor cells was found in 57 (81.4%) patients and did not correlate with tumor grade, stage of disease, number of recurrences, and progression of disease. COX-2 immunoreactivity in inflammatory cells was found in 16 of the 57 patients with COX-2 positive tumors, and was significantly related to the number of recurrences, time to appearance of the first recurrence, and disease progression.

Conclusions

COX-2 immunoreactivity in inflammatory stromal cells adjacent to the COX-2-positive tumor might be useful in clinical practice for selection of patients with a high risk of tumor recurrence and disease progression.

Correlation of BRAF Variant V595E, Breed, Histological Grade and Cyclooxygenase-2 Expression in Canine Transitional Cell Carcinomas

The presence of BRAF variant V595E, as well as an increased cyclooxygenase-2 (COX-2) expression in canine transitional cell carcinoma (TCC) are well-described in the literature. The aim of the present study was to investigate the correlation between breed (terrier versus non-terrier dogs), histological grade, COX-2 expression, and BRAF mutation in canine TCC. Therefore, transmural TCC biopsies from 65 dogs (15 terriers, 50 non-terriers) were graded histologically into low- and high-grade. Immunohistochemical evaluation of the intensity of COX-2 expression was performed using an immunoreactive score (IRS). Exon 15 of chromosome 16 was examined for the BRAF variant c.1799T>A by TaqMan^® SNP assay. TCC was low-grade in 20 cases (one terrier, 19 non-terriers) and high-grade in 45 cases (14 terriers, 31 non-terriers). Contrary to humans, histological grade was not significantly correlated to the intensity of COX-2 expression. BRAF mutation was detected in 11/15 (73%) TCC of terriers and in 18/50 (36%) TCC of non-terriers. Histological grade and BRAF mutation were not correlated significantly (p = 0.2912). Terriers had a considerably higher prevalence of high-grade tumors (p < 0.0001), as well as of BRAF mutation (p ≤ 0.05) compared to non-terriers. In non-terriers, neoplasms with BRAF mutation showed a significantly higher intensity of COX-2 expression than those without BRAF mutation (p ≤ 0.05). In conclusion, in contrast to humans, testing for BRAF mutation in canine TCC is a sensitive diagnostic method especially in terriers (73%) and may be recommended as a screening test. However, evidence of BRAF mutation in canine TCC is not a predictor for the histological grade. Moreover, a positive correlation between histological grade and the intensity of COX-2 expression was not found. Further studies are necessary to clarify the clinical and prognostic relevance of the elevated intensity of COX-2 expression of TCC with BRAF mutation detected in non-terriers.

Inflammatory gene mRNA expression in human peripheral blood and its association with colorectal cancer

Objective

The present study planned to investigate the changes in the mRNA expression of inflammatory genes and their association with colorectal cancer (CRC). Our findings could be useful for noninvasive early screening of CRC patients.

Patients and methods

Venous blood of 20 CRC cases and 15 healthy controls was collected. The mRNA expression of COX-2, TNF-α, NF-κB and IL-6 genes was carried out by using real-time polymerase chain reaction. Relative quantification was done to find out the fold change of these genes.

Results

The mean age of cases and controls was 55 and 50 years, respectively. The ΔCt of COX-2, TNF-α, NF-κB and IL-6 genes was significantly (p < 0.05) lower in cases as compared to controls. Subsequently, the mRNA expression of these genes was, respectively, 3.56-, 3.4-, 1.71- and 3.86-fold higher in CRC cases as compared to controls. Positive correlation of ΔCt of COX-2 was found with ΔCt of TNF-α (r = 0.461, p = 0.041) and NF-κB (r = 0.536, p = 0.015) in CRC cases. The mRNA expression of COX-2 was significantly lower in T2 stage, while mRNA expression of NF-κB was significantly lower in both T2 and T3 stages of CRC as compared to T4 stage.

Conclusion

The increased mRNA expression of COX-2 along with the high mRNA expression of TNF-α, NF-κB and IL-6 genes may be associative risk factors for CRC. COX-2 and NF-κB genes were more expressed in advanced stages of CRC indicating their role in tumor progression. Our findings support the possible role of blood biomarker in the screening of CRC patients in the early stages.

Halobenzoquinone-Induced Alteration of Gene Expression Associated with Oxidative Stress Signaling Pathways

Halobenzoquinones (HBQs) are emerging disinfection byproducts (DBPs) that effectively induce reactive oxygen species and oxidative damage in vitro. However, the impacts of HBQs on oxidative-stress-related gene expression have not been investigated. In this study, we examined alterations in the expression of 44 genes related to oxidative-stress-induced signaling pathways in human uroepithelial cells (SV-HUC-1) upon exposure to six HBQs. The results show the structure-dependent effects of HBQs on the studied gene expression. After 2 h of exposure, the expression levels of 9 to 28 genes were altered, while after 8 h of exposure, the expression levels of 29 to 31 genes were altered. Four genes ( HMOX1, NQO1, PTGS2, and TXNRD1) were significantly upregulated by all six HBQs at both exposure time points. Ingenuity pathway analysis revealed that the Nrf2 pathway was significantly responsive to HBQ exposure. Other canonical pathways responsive to HBQ exposure included GSH redox reductions, superoxide radical degradation, and xenobiotic metabolism signaling. This study has demonstrated that HBQs significantly alter the gene expression of oxidative-stress-related signaling pathways and contributes to the understanding of HBQ-DBP-associated toxicity.

Arterial stiffness induces remodeling phenotypes in pulmonary artery smooth muscle cells via YAP/TAZ-mediated repression of cyclooxygenase-2

Pulmonary arterial stiffness is an independent risk factor for mortality in pulmonary hypertension (PH) and plays a critical role in PH pathophysiology. Our laboratory has recently demonstrated arterial stiffening early in experimental PH, along with evidence for a mechanobiological feedback loop by which arterial stiffening promotes further cellular remodeling behaviors (Liu F, Haeger CM, Dieffenbach PB, Sicard D, Chrobak I, Coronata AM, Suárez Velandia MM, Vitali S, Colas RA, Norris PC, Marinković A, Liu X, Ma J, Rose CD, Lee SJ, Comhair SA, Erzurum SC, McDonald JD, Serhan CN, Walsh SR, Tschumperlin DJ, Fredenburgh LE. JCI Insight 1: e86987, 2016). Cyclooxygenase-2 (COX-2) and prostaglandin signaling have been implicated in stiffness-mediated regulation, with prostaglandin activity inversely correlated to matrix stiffness and remodeling behaviors in vitro, as well as to disease progression in rodent PH models. The mechanism by which mechanical signaling translates to reduced COX-2 activity in pulmonary vascular cells is unknown. The present work investigated the transcriptional regulators Yes-associated protein (YAP) and WW domain-containing transcription regulator 1 (WWTR1, a.k.a., TAZ), which are known drivers of downstream mechanical signaling, in mediating stiffness-induced changes in COX-2 and prostaglandin activity in pulmonary artery smooth muscle cells (PASMCs). We found that YAP/TAZ activity is increased in PAH PASMCs and experimental PH and is necessary for the development of stiffness-dependent remodeling phenotypes. Knockdown of YAP and TAZ markedly induces COX-2 expression and downstream prostaglandin production by approximately threefold, whereas overexpression of YAP or TAZ reduces COX-2 expression and prostaglandin production to near undetectable levels. Together, our findings demonstrate a stiffness-dependent YAP/TAZ-mediated positive feedback loop that drives remodeling phenotypes in PASMCs via reduced COX-2 and prostaglandin activity. The ability to interrupt this critical mechanobiological feedback loop and enhance local prostaglandin activity via manipulation of YAP/TAZ signaling presents a highly attractive novel strategy for the treatment of PH.

Clinical and prognosis relevance of COX-2 expression in Tunisian patients with primary gastric adenocarcinoma

BACKGROUND

Inflammation and hormonal signalling induce the cyclooxygenase-2 (COX-2) expression in various human cancers including Gastric Cancer (GC). GC remains among the human malignancies diagnosticated at advanced tumor stage and thus having a poor prognosis. COX-2 is a key protein in cancer progression which is involved in proliferation, invasion, and metastasis of tumor cells.

OBJECTIVE

The aim of this study was to investigate the expression of COX-2 and its association with clinico-patholocigal parameters and survival in Tunisian GC patients and to correlate COX-2 expression with others cancer-related proteins.

METHODS

The immunohistochemistry was used to study the expression of COX-2 on 93 patients with gastric adenocarcinoma.

RESULTS

Our results show that COX-2 immunostaining is negative to weak in 51.6%, moderate in 33.3%, and intense in 15.1% of tumor tissues. The expression of COX-2 associated significantly with tumor differentiation (p = 0.003), and histological type (p = 0.039). Furthermore, lack of COX-2 expression is significantly associated with 1-year (p= 0.005), 2-years (p= 0.000), and 5-years (p= 0.042) relapse free survival. In addition, Cox regression model, revealed that metastasis (p= 0.014), tumor site (p= 0.013), histotype (p = 0.02), and COX-2 expression (p = 0.003) are independent factors for prognosis. Regarding the relationship between COX-2 and cancer related proteins, we found that COX-2 expression is positively associated with APC (p = 0.006), and P53 (p = 0.026), supporting a cross link between these proteins in gastric carcinogenesis.

CONCLUSION

Our findings emphasize the importance of COX-2 as a potential marker of tumor progression and prognosis in GC, and that the inhibition of COX-2 activity may have a therapeutic benefit in GC.

COX2/mPGES1/PGE2 pathway regulates PD-L1 expression in tumor-associated macrophages and myeloid-derived suppressor cells

In recent years, it has been established that programmed cell death protein ligand 1 (PD-L1)-mediated inhibition of activated PD-1⁺ T lymphocytes plays a major role in tumor escape from immune system during cancer progression. Lately, the anti-PD-L1 and -PD-1 immune therapies have become an important tool for treatment of advanced human cancers, including bladder cancer. However, the underlying mechanisms of PD-L1 expression in cancer are not fully understood. We found that coculture of murine bone marrow cells with bladder tumor cells promoted strong expression of PD-L1 in bone marrow-derived myeloid cells. Tumor-induced expression of PD-L1 was limited to F4/80⁺ macrophages and Ly-6C⁺ myeloid-derived suppressor cells. These PD-L1-expressing cells were immunosuppressive and were capable of eliminating CD8 T cells in vitro. Tumor-infiltrating PD-L1⁺ cells isolated from tumor-bearing mice also exerted morphology of tumor-associated macrophages and expressed high levels of prostaglandin E₂ (PGE₂)-forming enzymes microsomal PGE₂ synthase 1 (mPGES1) and COX2. Inhibition of PGE₂ formation, using pharmacologic mPGES1 and COX2 inhibitors or genetic overexpression of PGE₂-degrading enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH), resulted in reduced PD-L1 expression. Together, our study demonstrates that the COX2/mPGES1/PGE₂ pathway involved in the regulation of PD-L1 expression in tumor-infiltrating myeloid cells and, therefore, reprogramming of PGE₂ metabolism in tumor microenvironment provides an opportunity to reduce immune suppression in tumor host.

A Histone Deacetylase Inhibitor, OBP-801, and Celecoxib Synergistically Inhibit the Cell Growth with Apoptosis via a DR5-Dependent Pathway in Bladder Cancer Cells

The prognosis of muscle-invasive bladder cancer with metastasis is poor. There have been no therapeutic improvements for many years, and an innovative therapy for muscle-invasive bladder cancer has been awaited to replace the conventional cytotoxic chemotherapy. Here, we show a candidate method for the treatment of bladder cancer. The combined treatment with a novel histone deacetylase (HDAC) inhibitor, OBP-801, and celecoxib synergistically inhibited cell growth and markedly induced apoptosis through the caspase-dependent pathway in high-grade bladder cancer cells. Furthermore, the combined treatment induced expression of death receptor 5 (DR5). We identified that knockdown of DR5 by small interfering RNA (siRNA) significantly suppressed apoptosis by the combined treatment. Therefore, we conjectured that the apoptosis induced by OBP-801 and celecoxib is at least partially dependent on DR5. However, it was interesting that the combined treatment drastically suppressed expression of DR5 ligand, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). These data suggest that there is no involvement of TRAIL in the induction of apoptosis by the combination, regardless of the dependence of DR5. Moreover, xenograft studies using human bladder cancer cells showed that the combined therapy suppressed tumor growth by upregulating expressions of DR5 and Bim. The inhibition of tumor growth was significantly more potent than that of each agent alone, without significant weight loss. This combination therapy provided a greater benefit than monotherapy in vitro and in vivo These data show that the combination therapy with OBP-801 and celecoxib is a potential novel therapeutic strategy for patients with muscle-invasive bladder cancer. Mol Cancer Ther; 15(9); 2066-75. ©2016 AACR.

Inflammatory networks underlying colorectal cancer

Inflammation is emerging as one of the hallmarks of cancer, yet its role in most tumors remains unclear. Whereas a minority of solid tumors are associated with overt inflammation, long-term treatment with non-steroidal anti-inflammatory drugs is remarkably effective in reducing cancer rate and death. This indicates that inflammation might have many as-yet-unrecognized facets, among which an indolent course might be far more prevalent than previously appreciated. In this Review, we explore the various inflammatory processes underlying the development and progression of colorectal cancer and discuss anti-inflammatory means for its prevention and treatment.

Suppressive Effect of Matrine on Tumor Invasion in N-Butyl-N-(4-Hydroxybutyl)Nitrosamine-Induced Urinary Bladder Carcinogenesis

AIMS

This study was designed to investigate the mechanisms and suppressive effects of matrine on the development of urinary bladder cancers induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in rats.

METHODS

Male Sprague-Dawley rats were given BBN (200 mg/rat) twice a week for a period of 8 weeks. Oral administration of matrine (50 and 100 mg/kg) was started 1 week before BBN exposure for 35 weeks. Half of each bladder was histopathologically analyzed and the remainder was extracted for protein analysis by Western blot.

RESULTS

The bladders of BBN-treated rats demonstrated progression from epithelial hyperplasia to papillary urothelial neoplasia and even poorly differentiated invasive cancer. Matrine (50 and 100 mg/kg) treatment decreased the formation of large bladder tumors by 31.6 and 21.1%, respectively. An incidence of cancer cells was detected in rats given BBN [70% (14/20)] and matrine [50 mg/kg: 68.4% (13/19) and 100 mg/kg: 57.9% (11/19), respectively]. The frequency of invasive tumors in the matrine treatment groups [50 mg/kg: 15.4% (2/13), 100 mg/kg: 9.1% (1/11)] was significantly lower than in the BBN-alone group [57% (8/14)]. Furthermore, oral administration of matrine (50 and 100 mg/kg) markedly attenuated the BBN-induced upregulation of bladder cyclooxygenase-2 (COX-2) expression and the elevation of bladder cytosolic phospholipase A2 (cPLA2) levels. Although the contents of 15-prostaglandin dehydrogenase (PGDH), which degrades PGE2, were dramatically reduced by BBN, matrine exerted no effects on reduced PGDH contents.

CONCLUSION

Our results suggest that matrine suppressed bladder tumor invasion in a rat model, and this might be primarily mediated through regulation of the protein contents, COX-2 and cPLA2 in the bladder.

Expression of Prostacyclin-Synthase in Human Breast Cancer: Negative Prognostic Factor and Protection against Cell Death In Vitro

Endogenously formed prostacyclin (PGI2) and synthetic PGI2 analogues have recently been shown to regulate cell survival in various cell lines. To elucidate the significance of PGI2 in human breast cancer, we performed immunohistochemistry to analyze expression of prostacyclin-synthase (PGIS) in 248 human breast cancer specimens obtained from surgical pathology files. We examined patients' 10-year survival retrospectively by sending a questionnaire to their general practitioners and performed univariate analysis to determine whether PGIS expression correlated with patient survival. Lastly, the effects of PGI2 and its analogues on cell death were examined in a human breast cancer cell line (MCF-7) and a human T-cell leukemia cell line (CCRF-CEM). PGIS expression was observed in tumor cells in 48.7% of samples and was associated with a statistically significant reduction in 10-year survival (P = 0.038; n = 193). Transient transfection of PGIS into MCF-7 cells exposed to sulindac increased cell viability by 50% and exposure to carbaprostacyclin protected against sulindac sulfone induced apoptosis in CCRF-CEM cells. Expression of PGIS is correlated with a reduced patient survival and protects against cell death in vitro, suggesting that PGIS is a potential therapeutic target in breast cancer.

Disruption of prostaglandin E2 receptor EP4 impairs urinary concentration via decreasing aquaporin 2 in renal collecting ducts

The antidiuretic hormone arginine vasopressin is a systemic effector in urinary concentration. However, increasing evidence suggests that other locally produced factors may also play an important role in the regulation of water reabsorption in renal collecting ducts. Recently, prostaglandin E2 (PGE2) receptor EP4 has emerged as a potential therapeutic target for the treatment of nephrogenic diabetes insipidus, but the underlying mechanism is unknown. To evaluate the role of EP4 in regulating water homeostasis, mice with renal tubule-specific knockout of EP4 (Ksp-EP4(-/-)) and collecting duct-specific knockout of EP4 (AQP2-EP4(-/-)) were generated using the Cre-loxP recombination system. Urine concentrating defect was observed in both Ksp-EP4(-/-) and AQP2-EP4(-/-) mice. Decreased aquaporin 2 (AQP2) abundance and apical membrane targeting in renal collecting ducts were evident in Ksp-EP4(-/-) mice. In vitro studies demonstrated that AQP2 mRNA and protein levels were significantly up-regulated in mouse primary inner medullary collecting duct (IMCD) cells after pharmacological activation or adenovirus-mediated overexpression of EP4 in a cAMP/cAMP-response element binding protein-dependent manner. In addition, EP4 activation or overexpression also increased AQP2 membrane accumulation in a mouse IMCD cell line (IMCD3) stably transfected with the AQP2 gene, mainly through the cAMP/protein kinase A and extracellular signal-regulated kinase pathways. In summary, the EP4 receptor in renal collecting ducts plays an important role in regulating urinary concentration under physiological conditions. The ability of EP4 to promote AQP2 membrane targeting and increase AQP2 abundance makes it a potential therapeutic target for the treatment of clinical disorders including acquired and congenital diabetes insipidus.

Senescence-associated inflammatory responses: aging and cancer perspectives

Senescent cells, albeit not proliferating, are metabolically and transcriptionally active, thereby capable of affecting their microenvironment, notably via the production of inflammatory mediators. These mediators maintain and propagate the senescence process to neighboring cells, and then recruit immune cells for clearing senescent cells. Among the inflammatory cues are molecules with pronounced tumor-controlling properties, both growth and invasion factors and inhibitory factors, working directly or via recruited immune cells. These senescence-inflammatory effects also prevail within tumors, mediated by the senescent tumor cells and the senescent tumor stroma. Here, we review the course and impact of senescence-associated inflammatory responses in aging and cancer. We propose that controlling senescence-associated inflammation by targeting specific inflammatory mediators may have a beneficial therapeutic effect in treatment of cancer and aging-related diseases.

Prostacyclin synthase: upregulation during renal development and in glomerular disease as well as its constitutive expression in cultured human mesangial cells

Prostacyclin (PGI₂) plays a critical role in nephrogenesis and renal physiology. However, our understanding of how prostacyclin release in the kidney is regulated remains poorly defined. We studied expression of prostacyclin synthase (PGIS) in developing and adult human kidneys, and also in selected pediatric renal diseases. We also examined PGI₂ formation in human mesangial cells in vitro. We observed abundant expression of PGIS in the nephrogenic cortex in humans and in situ hybridization revealed an identical pattern in mice. In the normal adult kidney, PGIS-immunoreactive protein and mRNA appear to localize to mesangial fields and endothelial and smooth muscle cells of arteries and peritubular capillaries. In kidney biopsies taken from pediatric patients, enhanced expression of PGIS-immunoreactive protein was noted mainly in endothelial cells of patients with IgA-nephropathy. Cultured human mesangial cells produce primarily PGI₂ and prostaglandin E₂, followed by prostaglandin F₂α Cytokine stimulation increased PGI₂ formation 24-fold. Under these conditions expression of PGIS mRNA and protein remained unaltered whereas mRNA for cyclooxygenase-2 was markedly induced. In contrast to its constitutive expression in vitro, renal expression of prostacyclin-synthase appears to be regulated both during development and in glomerular disease. Further research is needed to identify the factors involved in regulation of PGIS-expression.

Adenovirus-mediated IL-24 confers radiosensitization to human lung adenocarcinoma in vitro and in vivo

The current paper aims to study the effect of adenovirus-mediated IL-24 (Ad-IL-24) on human lung adenocarcinoma in vitro and in vivo and determine its possible mechanism of action. The growth-suppressing and apoptosis-inducing effects of Ad-IL-24, radiotherapy, and Ad-IL-24+ radiotherapy (hereinafter referred to as the joint group) on SPC-A1 lung carcinoma cells were assessed by using 3-(4,5-dimethyliazolyl-2)-2,5-diphnyltetrazolium bromide and flow cytometry. A human lung model was established with SPC-A1 cells in nude mice. Groups of mice were subjected to multi-point injections to their tumors. Gross tumor volumes were measured dynamically. The ratios of tumor suppression and radiosensitization effect were evaluated according to the method of probability sum Q values. The expressions of Bax, Bcl-2, Survivin, and Caspase-3 in tumor samples were detected by immunohistochemistry. The ratios of inhibition and apoptosis in the joint group were higher than those in the individual Ad-IL-24 and radiotherapy groups. In vitro, the joint group suppressed tumor growth conspicuously, showing a weight inhibition rate of about 64 %. The expressions of FasL, Bax and Caspase-3 were upregulated in the joint group, while the expressions of Cox,Bcl-2,VEGF,CD34 and Survivin were downregulated. The current study proves that Ad-IL-24 suppresses growth of SPC-A1 cells both in vitro and in vivo. Its functions appear to be related to cell apoptosis and antiangiogenesis.

Arsenic induced overexpression of inflammatory cytokines based on the human urothelial cell model in vitro and urinary secretion of individuals chronically exposed to arsenic

Chronic persistent inflammation could play an important role in the pathogenesis of some malignancies, and inflammation is a critical factor for bladder cancer development. In this study, we measured urine levels of transforming growth factor-α (TGF-α), tumor necrosis factor-α (TNF-α), and IL-8 in arsenic exposure workers and expressions of inflammatory cytokines in human urothelial cells in vivo and in vitro. We found the concentrations of IL-8, TNF-α, and TGF-α presented in urine were significantly elevated in the high urinary arsenic workers compared with the low urinary arsenic workers. Multiple regression analysis showed that the urinary IL-8 level was significantly positively associated with urinary iAs concentration after adjusting for the confounding effects of age, employed years, body mass index (BMI), smoking, alcohol, and seafood consumption in recent 3 days. Urinary TNF-α and TGF-α levels were also significantly positively associated with urinary iAs concentration, and SMI. TGF-α level was negatively associated with age after adjusting for the confounding effects. Consistent with the results in vivo, mRNA expressions of TNF-α, TGF-α, and IL-8 and protein expressions of TGF-α, TGF-β1, and IL-8 were significantly elevated in SV-HUC-1 cells after exposure to lower concentrations of arsenite for 24h as compared to the control group. These data indicated that arsenic increased the secretion of inflammatory factors and IL-8, TNF-α, and TGF-α expression may be a useful biomarker of the effect of arsenic exposure.

Piroxicam inhibits Masitinib-induced cyclooxygenase 2 expression in oral squamous cell carcinoma cells in vitro

Development and characterization of animal models for human cancers is important for the improvement of diagnosis and therapy. The oral squamous cell carcinoma (OSCC) of domestic animals resembles human OSCC in many aspects; thus, cell lines derived from OSCC of cats and dogs are a valuable model for human OSCC. We characterized 1 feline OSCC (FeOSCC-Sidney) and 1 canine OSCC (K9OSCC-Abby) cell line and compared their characteristics with human OSCC cell line hSCC-25. We calculated the doubling time of the new OSCC cell lines and evaluated the expression profiles of cancer-related markers and cell-cycle proteins such as c-kit, platelet-derived growth factor receptor, vascular endothelial growth factor receptor, epidermal growth factor receptor, cyclooxygenase (COX)-1, COX-2, and p27 by immunocytochemistry and Western blot analysis. We evaluated the effects of novel receptor tyrosine kinase inhibitor (Masitinib, AB1010) and the nonsteroidal anti-inflammatory drug piroxicam on the previously mentioned OSCC cells. Interestingly, AB1010 increased expression levels of COX-2 in all tested OSCCs. Cotreatment of piroxicam with Masitinib significantly inhibited cell proliferation of OSCC as compared to either drug alone through the c-kit and AKT signaling pathways. Piroxicam inhibited Masitinib-induced COX-2 expression in all tested OSCCs. Therefore, targeting these two signaling pathways simultaneously was more efficient for inhibition of OSCCs across these species.

Animal model of naturally occurring bladder cancer: characterization of four new canine transitional cell carcinoma cell lines

Background

Development and further characterization of animal models for human cancers is important for the improvement of cancer detection and therapy. Canine bladder cancer closely resembles human bladder cancer in many aspects. In this study, we isolated and characterized four primary transitional cell carcinoma (K9TCC) cell lines to be used for future in vitro validation of novel therapeutic agents for bladder cancer.

Methods

Four K9TCC cell lines were established from naturally-occurring canine bladder cancers obtained from four dogs. Cell proliferation rates of K9TCC cells in vitro were characterized by doubling time. The expression profile of cell-cycle proteins, cytokeratin, E-cadherin, COX-2, PDGFR, VEGFR, and EGFR were evaluated by immunocytochemistry (ICC) and Western blotting (WB) analysis and compared with established human bladder TCC cell lines, T24 and UMUC-3. All tested K9TCC cell lines were assessed for tumorigenic behavior using athymic mice in vivo.

Results

Four established K9TCC cell lines: K9TCC#1Lillie, K9TCC#2Dakota, K9TCC#4Molly, and K9TCC#5Lilly were confirmed to have an epithelial-cell origin by morphology analysis, cytokeratin, and E-cadherin expressions. The tested K9TCC cells expressed UPIa (a specific marker of the urothelial cells), COX-2, PDGFR, and EGFR; however they lacked the expression of VEGFR. All tested K9TCC cell lines confirmed a tumorigenic behavior in athymic mice with 100% tumor incidence.

Conclusions

The established K9TCC cell lines (K9TCC#1Lillie, K9TCC#2Dakota, K9TCC#4Molly, and K9TCC#5Lilly) can be further utilized to assist in development of new target-specific imaging and therapeutic agents for canine and human bladder cancer.

Cyclooxygenase-2 expression in urinary bladder transitional cell carcinoma and its association with clinicopathological characteristics

BACKGROUND

Transitional cell carcinoma (TCC) is the most predominant type of urinary bladder tumor. As cyclooxygenase (COX)-2 is recently introduced as an attractive target molecule in bladder TCC, we evaluated the immunohistochemical expression of this marker and its association with several clinicopathological characteristics.

MATERIALS AND METHODS

This cross-sectional study was performed in the Pathology department of Sina Hospital in Tehran, Iran during 2006-2011. Ninety-two paraffin embedded blocks were selected from patients with urinary bladder TCC who underwent cystectomy or transurethral resection (TUR). Then, we assessed COX-2 expression by immunohistochemical staining using antibody against COX-2. Staining in more than 5% of tumor cells was considered as positive expression.

RESULTS

COX-2 was expressed in 50 % of our patients. This marker was markedly expressed in high grade bladder TCC (62.1%) versus other grades and there was statistically a significant difference in COX-2 expression between various grades (p=0.008). In addition, patients' age, lymphatic and perineurial invasion were associated with the expression of COX-2 (p=0.001, 0.015 and 0.039, respectively). However, other parameters such as stage, tumor size, venous invasion and lymph node metastasis did not show any significant relationship with this marker (all, p>0.05).

CONCLUSIONS

COX-2 was expressed in urinary bladder TCC especially in high grade forms, advocating its probable role in the differentiation of this tumor. Accordingly, COX-2 could be a valuable biological target molecule in the evaluation and treatment of patients with bladder TCC.

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.

Sodium arsenite induces cyclooxygenase-2 expression in human uroepithelial cells through MAPK pathway activation and reactive oxygen species induction

Arsenic can induce reactive oxygen species (ROS) leading to oxidative stress and carcinogenesis. Bladder is one of the major target organs of arsenic, and cyclooxygenase-2 (COX-2) may play an important role in arsenic-induced bladder cancer. However, the mechanism by which arsenic induces COX-2 in bladder cells remains unclear. This study aimed at investigating arsenic-mediated intracellular redox status and signaling cascades leading to COX-2 induction in human uroepithelial cells (SV-HUC-1). SV-HUC-1 cells were exposed to sodium arsenite and COX-2 expression, mitogen-activated protein kinase (MAPK) phosphorylation, glutathione (GSH) levels, ROS induction and Nrf2 expression were quantified. Our results demonstrate that arsenite (1-10 μM) elevates COX-2 expression, GSH levels, ROS and Nrf2 expression. Arsenite treatment for 24h stimulates phosphorylation of ERK and p38, but not JNK in SV-HUC-1 cells. Induction of Cox-2 mRNA levels by arsenite was attenuated by inhibitors of ERK, p38 and JNK. Arsenite-induced ROS generation and COX-2 expression were significantly attenuated by treatment with melatonin (a ROS scavenger), but enhanced by DL-buthionine-(S, R)-sulfoximine (BSO, an inhibitor of gamma-glutamylcysteine synthetase (γ-GCS) resulting in lower GSH and increased ROS levels). These data indicate that arsenite promotes an induction of ROS, which results in an induction of COX-2 expression through activation of the MAPK pathway.

Systematic review and meta-analysis of COX-2 expression and polymorphisms in prostate cancer

Evidence is accumulating that cyclooxygenase-2 (COX-2) may play an important role in prostate cancer (PCa). Recently, gene polymorphisms in COX-2 have been implicated to alter the risk of PCa and overexpression of COX-2 may be associated with clinical and prognostic significance in PCa. However, the results of these studies are inconclusive or controversial. To derive a more precise estimation of the relationships, we performed an updated meta-analysis. A comprehensive search was conducted to examine all the eligible studies of COX-2 polymorphism and expression in PCa. We used odds ratios (ORs) to assess the strength of the association and the 95 % confidence intervals (CIs) give a sense of the precision of the estimate. Overall, no significant associations between COX-2 polymorphism and PCa risk were found. However, high expression of COX-2 was significantly higher in T3-T4 stages of PCa than in T1-T2 stages of PCa (OR = 2.33, 95 %CI: 1.54-3.53, P < 0.0001). COX-2 might play an important role in the progress of PCa, overexpression of COX-2 correlates with T3-T4 stages of PCa. COX-2 might be a potential therapy target for PCa and work as a prognostic factor for PCa patients.

Cyclooxygenase-2 expression in bladder cancer and patient prognosis: results from a large clinical cohort and meta-analysis

Aberrant overexpression of cyclooxygenase-2 (COX2) is observed in urothelial carcinoma of the bladder (UCB). Studies evaluating COX2 as a prognostic marker in UCB report contradictory results. We determined the prognostic potential of COX2 expression in UCB and quantitatively summarize the results with those of the literature through a meta-analysis. Newly diagnosed UCB patients recruited between 1998–2001 in 18 Spanish hospitals were prospectively included in the study and followed-up (median, 70.7 months). Diagnostic slides were reviewed and uniformly classified by expert pathologists. Clinical data was retrieved from hospital charts. Tissue microarrays containing non-muscle invasive (n = 557) and muscle invasive (n = 216) tumours were analyzed by immunohistochemistry using quantitative image analysis. Expression was evaluated in Cox regression models to assess the risk of recurrence, progression and disease-specific mortality. Meta-hazard ratios were estimated using our results and those from 11 additional evaluable studies. COX2 expression was observed in 38% (211/557) of non-muscle invasive and 63% (137/216) of muscle invasive tumors. Expression was associated with advanced pathological stage and grade (p<0.0001). In the univariable analyses, COX2 expression - as a categorical variable - was not associated with any of the outcomes analyzed. As a continuous variable, a weak association with recurrence in non-muscle invasive tumors was observed (p-value = 0.048). In the multivariable analyses, COX2 expression did not independently predict any of the considered outcomes. The meta-analysis confirmed these results. We did not find evidence that COX2 expression is an independent prognostic marker of recurrence, progression or survival in patients with UCB.

Long-term NSAID use and incident urothelial cell carcinoma in the VITamins and Lifestyle (VITAL) study

PURPOSE

Literature on the chemopreventive role of nonsteroidal anti-inflammatory drugs (NSAIDs) in urothelial carcinoma of the bladder (UC) is conflicting. A recent pooled analysis of 3 cohorts reported regular use of nonaspirin NSAIDs was associated with reduced risk of urothelial carcinoma (UC) among nonsmokers only; however, nonsmokers are a group with a low risk of UC. We examine the association between NSAID use and UC risk.

MATERIALS AND METHODS

Study participants were members of the VITamins and Lifestyle (VITAL) cohort of 77,048 Washington State residents aged 50-76 years who completed a baseline questionnaire in 2000-2002 on NSAID use and cancer risk factors. Ten-year use of aspirin and other NSAIDs was categorized as none, low-use (1-3 d/wk or <4 years), or high-use (≥ 4 d/wk and ≥ 4 years). Incident UC cases were prospectively identified via linkage to a local cancer registry. Hazard ratios (HR) were estimated by multivariate Cox regression.

RESULTS

A total of 385 incident cases of UC were diagnosed over a mean follow-up of 7 years. There was no association with NSAID use and risk of UC. However, the association of use of nonaspirin NSAIDs with UC risk differed by smoking status (P for interaction = 0.02). Specifically, among long-term former smokers (quit ≥ 10 years), nonaspirin NSAID use was associated with a 31% reduction in risk of UC in low-users (HR 0.69, 95% CI 0.46-1.04), and 48% reduction in risk for high-users (HR 0.52, 95% CI 0.24-1.11, P for trend = 0.02).

CONCLUSIONS

Our results show a risk reduction with nonaspirin NSAID use among long-term quitters, a group with significant risk of UC.

FGFR1-induced epithelial to mesenchymal transition through MAPK/PLCγ/COX-2-mediated mechanisms

Tumour invasion and metastasis is the most common cause of death from cancer. For epithelial cells to invade surrounding tissues and metastasise, an epithelial-mesenchymal transition (EMT) is required. We have demonstrated that FGFR1 expression is increased in bladder cancer and that activation of FGFR1 induces an EMT in urothelial carcinoma (UC) cell lines. Here, we created an in vitro FGFR1-inducible model of EMT, and used this model to identify regulators of urothelial EMT. FGFR1 activation promoted EMT over a period of 72 hours. Initially a rapid increase in actin stress fibres occurred, followed by an increase in cell size, altered morphology and increased migration and invasion. By using site-directed mutagenesis and small molecule inhibitors we demonstrated that combined activation of the mitogen activated protein kinase (MAPK) and phospholipase C gamma (PLCγ) pathways regulated this EMT. Actin stress fibre formation was regulated by PLCγ activation, and was also important for the increase in cell size, migration and altered morphology. MAPK activation regulated migration and E-cadherin expression, indicating that combined activation of PLCγ and MAPK is required for a full EMT. We used expression microarrays to assess changes in gene expression downstream of these signalling cascades. COX-2 was transcriptionally upregulated by FGFR1 and caused increased intracellular prostaglandin E(2) levels, which promoted migration. In conclusion, we have demonstrated that FGFR1 activation in UC cells lines promotes EMT via coordinated activation of multiple signalling pathways and by promoting activation of prostaglandin synthesis.

Chemoprevention in bladder cancer: What's new?

Bladder cancer is the sixth most common tumour in Canada and ranks eighth in terms of cancer mortality. Up to now, management of this condition relied mostly on surgical and intravesical treatments once the disease is established. Chemoprevention is an attractive option to prevent the disease in high-risk populations and may well reduce the costs related to its treatment. This review examines the available data on chemoprevention strategies in bladder cancer, with special emphasis on randomized controlled trials when available.

Reciprocal correlation between the expression of cyclooxygenase-2 and E-cadherin in human bladder transitional cell carcinomas

Carcinoma cells become more motile and invasive via downmodulation of E-cadherin. Cyclooxygenase-2 (COX-2) expression is associated with tumor invasion and metastasis. The aim of this study is to investigate the relationship between the expression of COX-2 and E-cadherin in a bladder cancer cell line and human bladder transitional cell carcinoma (TCCs). Phorbol 12-myristate 13-acetate (PMA) treatment for 5637 bladder cancer cells increased COX-2 expression, slightly induced Slug expression, and decreased E-cadherin expression. Ectopic expression of COX-2 or prostaglandin E(2) (PGE(2)) treatment for 5637 cells reduced E-cadherin expression. This finding was confirmed by the result that knockdown of COX-2 expression or indomethacin administration increased the expression of E-cadherin. When compared with cells' motility in serum-free medium, the treatment of PMA and PGE(2) increased cell motility, and indomethacin treatment slightly decreased cell motility. In the tissues of bladder TCCs, COX-2 expression was inversely correlated with membranous E-cadherin expression and positively correlated with nuclear beta-catenin expression. The expression of COX-2 and nuclear beta-catenin expression was significantly higher in TCCs of high grade and invasive growth than in TCCs of low grade and noninvasive growth. In contrast, membranous E-cadherin expression was more decreased in tumors of high grade and invasive growth. In addition, nuclear beta-catenin expression was significantly related to tumor recurrence. We suggest that COX-2 pathway reduces membranous E-cadherin expression in bladder TCCs and their expression pattern may provide important information in predicting the clinical behavior of bladder TCCs.

The current state of head and neck cancer gene therapy

The incidence of head and neck cancer continues to increase worldwide, with tobacco exposure and human papillomavirus type 16 infections being the major etiological factors. Current therapeutic options are ineffective in approximately half of the individuals afflicted with this malignancy. Developments in the identification of molecules that sustain head and neck squamous cell carcinoma (HNSCC) growth and survival have made molecular targeting by gene therapy approaches a feasible therapeutic strategy. Although gene therapy was originally designed to correct single gene defects, it has now evolved to encompass all forms of therapeutic interventions involving engineered cells and nucleic acids that modify the overall pattern of gene expression within target tissues. Several preclinical studies and clinical trials have tested the efficacy of targeting specific molecules in patients with HNSCC, using genetic therapy approaches. This review discusses promising preclinical and clinical approaches and new directions for HNSCC gene therapy.

Study of arachidonic Acid pathway in human bladder tumor

Recent epidemiological studies and animal experiments have demonstrated that nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the incidence of colorectal carcinoma. Cyclooxygenase (COX) is the principal target of NSAIDs. COX is the first oxidase in the process of prostaglandin production from arachidonic acid. COX enzyme may be involved in the initiation and/or the promotion of tumorigenesis due to NSAIDs inhibition of COX. Lipoxygenase (LOX) is also an initial enzyme in the pathway for producing leukotrienes from arachidonic acid. Similar to COX, LOX enzyme may also be involved in the initiation and/or promotion of tumorigenesis. Peroxisome proliferator activator-receptor (PPAR)-γ is a ligand-activated transcriptional factor belonging to the steroid receptor superfamily. PPAR-γ plays a role in both adipocyte differentiation and tumorigenesis. PPAR-γ is one target for cell growth modulation of NSAIDs. In this review, we report the expression of COX-2, LOX and PPAR-γ in human bladder tumor tissues as well as the effects of COX-2 and LOX inhibitors and PPAR-γ ligand.

Inflammation and cancer: how friendly is the relationship for cancer patients?

Evidence has emerged in the last two decades that at the molecular level most chronic diseases, including cancer, are caused by a dysregulated inflammatory response. The identification of transcription factors such as NF-kappaB, AP-1 and STAT3 and their gene products such as tumor necrosis factor, interleukin-1, interleukin-6, chemokines, cyclooxygenase-2, 5 lipooxygenase, matrix metalloproteases, and vascular endothelial growth factor, adhesion molecules and others have provided the molecular basis for the role of inflammation in cancer. These inflammatory pathways are activated by tobacco, stress, dietary agents, obesity, alcohol, infectious agents, irradiation, and environmental stimuli, which together account for as much as 95% of all cancers. These pathways have been implicated in transformation, survival, proliferation, invasion, angiogenesis, metastasis, chemoresistance, and radioresistance of cancer, so much so that survival and proliferation of most types of cancer stem cells themselves appear to be dependent on the activation of these inflammatory pathways. Most of this evidence, however, is from preclinical studies. Whether these pathways have any role in prevention, progression, diagnosis, prognosis, recurrence or treatment of cancer in patients, is the topic of discussion of this review. We present evidence that inhibitors of inflammatory biomarkers may have a role in both prevention and treatment of cancer.

More Than Structural Cells, Fibroblasts Create and Orchestrate the Tumor Microenvironment

The tumor microenvironment comprises many cell types including infiltrating immune cells such as lymphocytes, endothelial cells and a complex stroma consisting mainly of fibroblasts. Fibroblasts are heterogeneous and consist of Thy-1+ and Thy-1- subsets that define different biosynthetic and differentiation potential. They produce mediators linked to carcinogenesis and metastasis, including Cox-2 and PGE2, both of which are also increased in most cancers. This review will highlight the emerging role of the complex fibroblastic stroma in establishing a microenvironment supporting malignant transformation, tumor growth and attenuation of host anti-tumor immune responses.

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.

Molecular Pathology of the Genitourinary Tract: Prostate and Bladder

The knowledge of cellular mechanisms in tumors of the prostate and bladder has grown exponentially. Molecular technologies have led to the discovery of TMPRSS2 in prostate cancer and the molecular pathways distinguishing low- and high-grade urothelial neoplasms. UroVysion with fluorescence in situ hybridization is already commonplace as an adjunct to cytologic diagnosis of urothelial neoplasms. This trend portends the future in which classification and diagnosis of tumors of the prostate and bladder through morphologic analysis will be supplemented by molecular information correlating with prognosis and targeted therapy. This article outlines tumor molecular pathology of the prostate and bladder encompassing current genomic, epigenomic, and proteonomic findings.

Combined action of celecoxib and ionizing radiation in prostate cancer cells is independent of pro-apoptotic Bax

BACKGROUND AND PURPOSE

The cyclooxygenase-2-inhibitor celecoxib has been shown to inhibit cell growth and to reduce prostatic intraepithelial neoplasia in mice. The drug was suggested to increase efficacy of ionizing radiation. However, extent and mechanisms of the suggested benefit of celecoxib on the radiation response are still unclear. The aim of the present study was to analyze cytotoxic efficacy of celecoxib in combination with irradiation on human prostate cancer cell lines and to define the importance of pro-apoptotic Bax in this process.

MATERIALS AND METHODS

Induction of apoptosis and global and clonogenic cell survival upon irradation- (2-10Gy), celecoxib- (10-75microM) or combined treatment were evaluated in prostate cancer cells by fluorescence microscopy, WST-1 assay and standard colony formation assays.

RESULTS

Celecoxib <25microM caused morphological changes and growth inhibition without substantial apoptosis or radiosensitization in terms of decreased clonogenic cell survival. In contrast, celecoxib 25microM increased radiation-induced cell death and clonogenic kill. While radiation-induced clonogenic death was increased in the presence of Bax, effects of celecoxib or combined treatment were Bax independent.

CONCLUSIONS

Our findings reveal Bax-independent beneficial effects of celecoxib on radiation-induced apoptosis and eradication of clonogenic prostate cancer cells in vitro providing a rationale for clinical evaluation of high-dose celecoxib in combination with irradiation in prostate cancer patients.

Possible role of cyclooxygenase-2 in schistosomal and non-schistosomal-associated bladder cancer

BACKGROUND AND PURPOSE

Cyclooxygenase (COX) is an angiogenic factor that is strongly related to inflammatory diseases and the development of cancer and metastasis in several cancers. It is overexpressed in a variety of premalignant and malignant conditions, including urinary bladder cancer. Our aim was to investigate and compare the expression of COX-2 enzyme in patients with bladder cancer, chronic cystitis, and normal bladder tissue. The results were correlated to the classic prognostic factors, mainly tumor stage and grade, in a trial to determine the prognostic significance of COX-2 marker.

MATERIALS AND METHODS

Seventy-five bladder samples were taken, including 50 cases with bladder cancer (31 were schistosomal-associated and 19 non-schistosomal-associated), 20 samples from cases with chronic cystitis (7 were nonschistosomal and 13 were schistosomal cystitis), and 5 samples from normal bladder tissue taken as control. The specimens were stained by streptavidin-biotin immunohistochemistry protocol, with COX-2 monoclonal antibody.

RESULTS

Although no notable expression of COX-2 was observed in the normal bladder, it was slightly expressed in chronic cystitis especially in areas of dysplasia and squamous metaplasia, whereas there was a significant increase in COX-2 (P < .001) with moderate-to-strong granular cytoplasmic expression in all malignant histologic types. The COX-2 reactivity was higher in transitional cell carcinoma (TCC) than in squamous cell carcinoma (SqCC) (P < .01). COX-2 expression was significantly higher in schistosomal-associated TCC than in non-schistosomal-associated TCC (P < .01). There was a statistically significant positive correlation between COX-2 expression and tumor grade (P = .0052). COX-2 expression was significantly higher in grade 3 bladder TCC than in grades 1 and 2 bladder TCC (P < .05, P < .01). A correlation between COX-2 expression and progression of bladder TCC also was observed (P = .001). There was a significant difference in COX-2 expression level between the bladder TCCs at different clinical stages (P < .01).

CONCLUSION

COX-2 is overexpressed in schistosomal-associated bladder cancer. COX-2 may be of significance to the development and proliferation of bladder TCC, consistent with a potential role for COX-2 inhibitors in the prevention and management of this disease.