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Objectives: To study the prognostic impact of muscularis mucosae (MM) invasion for pT1 bladder cancer treated by transurethral resection (TUR) and adjuvant Bacille Calmette-Guerin (BCG) intravesical immunotherapy., Methods: Sixty-six patients treated by BCG intravesical instillations were substaged into pT1a and pT1b, regarding Muscularis Mucosae invasion. Tumor grade, associated carcinoma in situ (CIS), multifocality, tumoral size up to 3cm, BCG maintenance were noted. With a mean follow-up of 50.5±38 months, we studied recurrence, progression, overall and specific survival. Cox's model method was used for multivariate analysis., Results: Tumor recurrence was observed in 30±7% and 43±10% (P=0.29) and tumor progression in 16.3±5% and 39±10% (P=0.04) for pT1a and pT1b. The rate of progression was higher (P=0.04) and progression free survival was decreased (P=0.04) for pT1b. Specific death rates were 11±5% and 21±9% (P=0.28), median overall survival was 80.9 [1.5-92] and 48.2 [12-93] months for pT1a and pT1b. Overall and specific survival weren't different between the two populations (P=0.38; P=0.3). Cystectomy rates were 2.3±2% and 30±9% for pT1a and PT1b (P=0.0006). For pT1a patients, recurrence (P=0.8) or progression rates (P=0.64) were no different regarding BCG maintenance immunotherapy but pT1b population had a better progression free survival with BCG maintenance than without (P=0.0051). Only CIS had prognostic value in multivariate analysis., Conclusions: Tumors with Muscularis Mucosae invasion have a higher risk of progression and BCG failure. Maintenance immunotherapy should be given to improve results with these patients., (Copyright © 2011. Published by Elsevier Masson SAS.)

The present investigation was conducted first to determine whether correlation exists between VEGF-A and -B mRNA levels and clinicopathological parameters and to assess their prognostic value in bladder cancer, then to clarify the expression level and biological significance of VEGF-A isoforms. Total RNA was isolated from 37 specimens of bladder cancer. Northern blot analysis revealed that VEGF-B mRNA was not expressed either in normal urothelium or in bladder cancer and detected three VEGF-A transcripts of 5.2, 4.5 and 1.7 kb in length, respectively. The VEGF-A transcript levels were greater in cancer tissues than in normal urothelium. They were significantly higher in pT2-T4 than in pTa and pT1 urothelial tumors and thus, were correlated to the pathologic stage. Contrary to the 4.5 kb transcript, elevated expression of the 5.2 and 1.7 kb transcripts was correlated with the histologic grade and the presence of carcinoma in situ. Patients with higher VEGF-A mRNA levels had a significantly shorter survival without progression compared to those with lower levels. Three VEGF-A splice variants were detected by southern blotting namely, VEGF121, 165 and 189. The expression intensity of each isoform was evaluated by quantitative real-time RT-PCR in 20 new fresh frozen recent tumors. VEGF121 and VEGF165 were expressed at the similar level. On the contrary, they were significantly more expressed than VEGF189 (p<0.05). The three isoforms were higher expressed in pT2 bladder cancers than in pTa tumors (p<0.05). There was only a significant correlation between the increased expression level of VEGF121 and 165 and the histological grade of the lesion (p<0.05). To conclude, VEGF-A mRNA level is a potential prognostic indicator of progression in bladder cancer as well as the expression level of the different VEGF-A splice variants.

The growth of any solid tumor depends on angiogenesis. Vascular endothelial growth factor (VEGF) plays a prominent role in vesical tumor angiogenesis regulation. Previous studies have shown that the peroxisome proliferator-activated receptor gamma (PPARgamma) was involved in the angiogenesis process. Here, we report for the first time that in two different human bladder cancer cell lines, RT4 (derived from grade I tumor) and T24 (derived from grade III tumor), VEGF (mRNA and protein) is differentially up-regulated by the three PPAR isotypes. Its expression is increased by PPARalpha, beta, and gamma in RT4 cells and only by PPARbeta in T24 cells via a transcriptional activation of the VEGF promoter through an indirect mechanism. This effect is potentiated by an RXR (retinoid-X-receptor), selective retinoid LG10068 providing support for a PPAR agonist-specific action on VEGF expression. While investigating the downstream signaling pathways involved in PPAR agonist-mediated up-regulation of VEGF, we found that only the MEK inhibitor PD98059 reduced PPAR ligand-induced expression of VEGF. These data contribute to a better understanding of the mechanisms by which PPARs regulate VEGF expression. They may lead to a new therapeutic approach to human bladder cancer in which excessive angiogenesis is a negative prognostic factor.

Purpose: Vascular endothelial growth factor is an overriding growth factor mediating tumor angiogenesis. We correlated serum vascular endothelial growth factor in patients with bladder cancer with clinical parameters., Materials and Methods: Serum vascular endothelial growth factor in 58 patients with bladder cancer, including superficial and invasive tumors in 42 and 16, respectively, and 41 healthy controls was measured by sandwich enzyme immunoassay., Results: Significant differences in serum vascular endothelial growth factor were observed in healthy controls and patients with bladder cancer (mean 248 versus 100 pg./ml., p <0.001). The serum level was significantly associated with tumor stage (p <0.0001), grade (p <0.002), vascular invasion (p <0.001) and carcinoma in situ (p <0.01). Patients with metastasis had a significantly higher levels than those with localized diseases (mean 582 versus 194 pg./ml., p <0.0001). At a cut-off of 400 pg./ml. the sensitivity and specificity of the test for differentiating patients with and without metastatic diseases was 87.5% and 98%, respectively (p <0.0001). Univariate statistical analysis showed that an increase in serum vascular endothelial growth factor level greater than 400 pg./ml. was significantly related to disease-free survival. On multivariate analysis only stage remained as an independent prognostic factor., Conclusions: Although vascular endothelial growth factor did not remain an independent prognostic factor on multivariate analysis, our data indicate that the level of vascular endothelial growth factor may be a valuable angiogenic marker for identifying metastatic bladder cancer. It may be used as a new predictor of disease.

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor associated with the growth and metastasis of various cancers and plays a prominent role in vesical angiogenesis regulation. In this study, we investigated the effect of the phorbol 12-myristate 13-acetate (PMA) on the expression of VEGF in human bladder transitional carcinoma cells (RT4). RT4 cells expressed three VEGF isoforms (VEGF(189), VEGF(165), VEGF(121)). PMA increased VEGF mRNA expression time-dependently with a peak at 4 h. PMA increased the half-life of VEGF mRNA. The amount of VEGF protein in conditioned media was increased by PMA in a dose-dependent manner with a maximal effect at 10(-7) M. Staurosporine and calphostin C (PKC inhibitors) decreased PMA-induced VEGF mRNA expression as opposed to protein kinase A or cyclic nucleotide-dependent protein kinase inhibitors. Thus, in RT4 cells, VEGF expression is up-regulated by PMA via the PKC signalling pathway and according to a posttranscriptional mechanism.

Angiogenesis is a complex, multi-step process which leads to the formation of new blood capillaries (neovessels) from preexisting vessels. It is essential top the growth of solid tumours and tumour metastasis (tumour angiogenesis). This process is initiated by the synthesis, by tumour cells and non-malignant tumour-associated cells, of growth factors called antigenic factors or inducers. bFGF (basic Fibroblast Growth Factor) and VEGF (Vascular Endothelial Growth Factor) are the two angiogenic factors involved in bladder tumour angiogenesis. The angiogenic activity of a bladder tumour can be measured by the microvascular density (MVD), considered by some authors to be an independent prognostic indicator of recurrence and survival in the group of invasive bladder tumours. VEGF expression in bladder tumours and biological fluids (serum, urine) appears to be a predictive marker of the risk of progression of superficial bladder tumours. Urinary bFGF assay reveals high levels in patients with bladder tumour, but this elevation is not specific to bladder tumours. Inhibition of tumour angiogenesis has become a therapeutic target. Intravesical suramine and a fumagillin analogue (TNP-470) have given promising results in terms of efficacy and safety in the treatment of bladder tumours.

The antioncogene p53 has been the subject of many studies in the field of bladder cancer, for many years and there appears to be a good correlation between p53 protein overexpression and pejorative clinicopathological factors, but contradictory results have been reported concerning its prognostic value. These discordances can be partly explained by the various immunohistochemical methods used in published series. Standardization of a highly sensitive and specific immunohistochemical method for the detection of p53 alterations now appears to be essential in order to accurately determine the value of p53 in the clinical management of bladder cancer.

The occurrence of upper urinary tract tumors has been studied in 479 patients followed for bladder cancer: The incidence rate is low (2.9%) but increases with time (mean: 58 months). Some patients are more exposed: those who underwent repeated transurethral resections of Ta-T1 multifocal bladder carcinoma. Retrograde and voiding cystourethrogram seems to be useful to select a group "at risk" during the follow-up of patients with bladder tumors treated by endoscopic resection: a yearly excretory urography for upper urinary tract survey should then be performed.