BackgroundPheochromocytoma (paraganglioma) of the urinary bladder is a rare tumor. Herein we sought to review the contemporary literature on pheochromocytomas of the urinary bladder in order to further illustrate the presentation, treatment options and outcomes of patients diagnosed with these tumors.MethodsA comprehensive review of the current literature was conducted according to the PRISMA guidelines by accessing the NCBI PubMed database and using the search terms “paraganglioma, pheochromocytoma, bladder.” This search resulted in the identification of 186 articles published between January 1980 and April 2012 of which 80 articles were ultimately included in our analysis.ResultsPheochromocytomas usually occurred in young adult Caucasians (mean age, 43.3 years; range,11–84 years). According to the literature, the most common symptoms and signs of pheochromocytomas of the urinary bladder were hypertension, headache, and hematuria. Of the 77 cases that commented on catecholamine production, 65 patients had biochemically functional tumors. Approximately 20% of patients were treated by transurethral resection alone, 70% by partial cystectomy and 10% by radical cystectomy. The 75 patients with follow-up information had a mean follow-up of 35 months. At the time of last follow-up, 15 (14.2%) had disease recurrence, 10 (9.4%) had metastasis, and 65 (61.3%) were alive.ConclusionsPheochromocytomas of the urinary bladder tend to be functional and occur mostly in young adult Caucasians. Patients with localized tumors have an extremely favorable prognosis and may be managed by less aggressive modalities, whereas patients with metastatic disease have a significant reduction in survival rates despite aggressive treatment.

BackgroundCancer invasion and metastasis develops through a series of steps that involve the loss of cell to cell and cell to matrix adhesion, degradation of extracellular matrix and induction of angiogenesis. Different protease systems (e.g., matrix metalloproteinases, MMPs) are involved in these steps. MMP-10, one of the lesser studied MMPs, is limited to epithelial cells and can facilitate tumor cell invasion by targeting collagen, elastin and laminin. Enhanced MMP-10 expression has been linked to poor clinical prognosis in some cancers, however, mechanisms underlying a role for MMP-10 in tumorigenesis and progression remain largely unknown. Here, we report that MMP-10 expression is positively correlated with the invasiveness of human cervical and bladder cancers.MethodsUsing commercial tissue microarray (TMA) of cervical and bladder tissues, MMP-10 immunohistochemical staining was performed. Furthermore using a panel of human cells (HeLa and UROtsa), in vitro and in vivo experiments were performed in which MMP-10 was overexpressed or silenced and we noted phenotypic and genotypic changes.ResultsExperimentally, we showed that MMP-10 can regulate tumor cell migration and invasion, and endothelial cell tube formation, and that MMP-10 effects are associated with a resistance to apoptosis. Further investigation revealed that increasing MMP-10 expression stimulates the expression of HIF-1α and MMP-2 (pro-angiogenic factors) and PAI-1 and CXCR2 (pro-metastatic factors), and accordingly, targeting MMP-10 with siRNA in vivo resulted in diminution of xenograft tumor growth with a concomitant reduction of angiogenesis and a stimulation of apoptosis.ConclusionTaken together, our findings show that MMP-10 can play a significant role in tumor growth and progression, and that MMP-10 perturbation may represent a rational strategy for cancer treatment.

Tumor angiogenesis is essential for tumor growth and metastasis and is dependent on key angiogenic factors. Angiogenin (ANG), a 14.2-kDa polypeptide member of the RNase A superfamily, is an angiogenic protein that has been reported to be upregulated and associated with poor prognosis in some human cancers. The mechanisms through which aberrant ANG levels promote specific steps in tumor progression are unknown. Here, we show that ANG expression in human tissues is strongly correlated with an invasive cancer phenotype. We also show that ANG induces cellular survival, proliferation, endothelial tube formation and xenograft angiogenesis and growth. Novel mechanistic investigations revealed that ANG expression stimulated matrix metallopeptidase-2 (MMP2) expression through the phosphorylation of ERK1/2. Targeting ANG in vivo with N65828, a small-molecule inhibitor of the ribonucleolytic activity of human ANG, resulted in the diminution of xenograft tumoral growth through the inhibition of angiogenesis. Our findings support an unrecognized interplay between ANG, ERK1/2 and MMP2 that can impact tumor growth and progression. The targeting of ANG and associated factors could provide a novel strategy to inhibit tumor establishment and growth.

BackgroundChemokines, including chemokine (C-X-C motif) ligand 1 (CXCL1), may regulate tumor epithelial-stromal interactions that facilitate tumor growth and invasion. Studies have linked CXCL1 expression to gastric, colon and skin cancers, but limited studies to date have described CXCL1 protein expression in human bladder cancer (BCa).MethodsCXCL1 protein expression was examined in 152 bladder tissue specimens (142 BCa) by immunohistochemical staining. The expression of CXCL1 was scored by assigning a combined score based on the proportion of cells staining and intensity of staining. CXCL1 expression patterns were correlated with clinicopathological features and follow-up data.ResultsCXCL1 protein expression was present in cancerous tissues, but was entirely absent in benign tissue. CXCL1 combined immunostaining score was significantly higher in high-grade tumors relative to low-grade tumors (p = 0.012). Similarly, CXCL1 combined immunostaining score was higher in high stage tumors (T2-T4) than in low stage tumors (Ta-T1) (p < 0.0001). An increase in the combined immunostaining score of CXCL1 was also associated with reduced disease-specific survival.ConclusionTo date, this is the largest study describing increased CXCL1 protein expression in more aggressive phenotypes in human BCa. Further studies are warranted to define the role CXCL1 plays in bladder carcinogenesis and progression.

The canonical function of Plasminogen activator inhibitor-1 (PAI-1/SERPINE1) is as an inhibitor of uPA for blood clot maintenance, but it is now also considered a pleiotropic factor that can exert diverse cellular and tumorigenic effects. However, the mechanism controlling its pleiotropic effects is far from being understood. To elucidate the tumorigenic role of PAI-1, we tested the effects of PAI-1 after manipulation of its expression or through the use of a small molecule inhibitor, tiplaxtinin. Down-regulation of PAI-1 significantly reduced cellular proliferation through an inability to progress from the G0/G1-phase of the cell cycle. Accordingly, overexpression of PAI-1 augmented proliferation by encouraging S-phase entry. Biochemically, cell cycle arrest was associated with the depletion of the G1-phase transition complexes, Cyclin D3/CDK4/6 and Cyclin E/CDK2, in parallel with the up-regulation of the cell cycle inhibitors p53, p21Cip1/Waf1 and p27Kip1. PAI-1 depletion significantly decreased the tumor size of urothelial T24 and UM-UC-14 xenografts and overexpression of PAI-1 substantially increased the tumor size of HeLa xenografts. Lastly, immunohistochemical analysis of human bladder and cervical tumor tissue microarrays revealed increased expression of PAI-1 in cancerous tissue, specifically in aggressive tumors, supporting the relevance of this molecule in human tumor biology.