Expression analysis of VEGF-A and VEGF-B: relationship with clinicopathological parameters in bladder cancer.

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.

A-FABP, a candidate progression marker of human transitional cell carcinoma of the bladder, is differentially regulated by PPAR in urothelial cancer cells.

Superficial pT1 bladder tumors are characterized by a high risk of recurrence and progression in grade and stage. Few studies provided evidence that loss of adipocyte-fatty acid binding protein (A-FABP) expression was associated with bladder cancer progression. A-FABP is a lipid binding protein playing a role in intracellular lipid transport and metabolism, as well as in signal transduction. We reported from bladder tumors that decrease of A-FABP transcript level significantly correlated to tumor stage and to histologic grade (p < 0.05). Namely, in poor prognosis high grade pT1 tumors there was a loss of A-FABP expression compared to good prognosis tumors suggesting that re-expression of A-FABP could be a therapeutic approach in early stage bladder cancer to prevent disease progression. We demonstrated for the first time that this marker is upregulated by Peroxisome Proliferator-Activated Receptor (PPAR) alpha, beta and gamma in T24 cells (derived from an undifferentiated grade III carcinoma) and only by PPARbeta in RT4 cells (derived from a well differentiated grade I papillary tumor). This effect occurred through a PPAR-dependent transcriptional mechanism without modifying mRNA stability and interestingly required de novo protein synthesis. Data as a whole suggest a prognostic significance of A-FABP in bladder cancer outcome and the potential utility of overexpression of this protein by PPAR agonists open up new perspectives in the treatment of bladder cancer. (c) 2008 Wiley-Liss, Inc.

[Malignant rhabdoid tumor of the liver with spontaneous rupture: a case report]. / Tumeur rhabdoïde hépatique maligne avec rupture spontanée: à propos d'un cas.

We report the case of an 8-year-old child, presenting a rhabdoid tumor of the liver with spontaneous rupture, revealed by an intra-abdominal bleeding with rapidly fatal course. This clinical and pathological report raises the problem of the differential diagnosis of primary malignant hepatic tumors of the child with no alpha-foetoprotein increase.

N-cadherin as a novel prognostic marker of progression in superficial urothelial tumors.

PURPOSE: Loss of intercellular adhesion and increased cell motility promote tumor cell invasion and spreading. In bladder cancer, loss or reduced E-cadherin expression has been associated with poor survival, and aberrant expression of N-cadherin has been associated with the invasive phenotype of bladder carcinoma cells. The purpose of this study was to investigate whether N-cadherin expression was associated with the bladder tumor progression. EXPERIMENTAL DESIGN: E-cadherin and N-cadherin expression was evaluated by immunohistochemistry in 101 tumors (pT1 and pT2-T3) and by reverse transcription-PCR analysis and immunohistochemistry in 28 other fresh frozen tumors (pT(a), pT1, and pT2-T3). RESULTS: N-cadherin expression was absent in normal urothelium, appeared in stage pT1, and increased in pT2-pT3 tumors. In most cases, increased N-cadherin expression in invasive tumors was associated with loss of E-cadherin expression. Progression-free survival and multivariate analyses revealed that N-cadherin expression is an independent prognostic marker for pT1 tumor progression. Analysis of the 28 frozen tumors by immunohistochemistry and reverse transcription-PCR showed a good correlation between protein and gene expression in pT1 and pT2-T3 tumors. Interestingly, in pT(a) tumors, N-cadherin was not immunodetected, whereas mRNA was present in 50% of cases. CONCLUSION: Regulatory defects in the N-cadherin promoter, abnormalities at the translational, or protein processing levels could explain the discrepancies between protein and mRNA expression. Most importantly, this study identified N-cadherin as a novel prognostic marker of progression in superficial urothelial tumors. Clearly, N-cadherin acts in an invasive mode in bladder cancer, but whether it has a primary role in urothelial neoplastic progression has yet to be investigated.

Expression of E-cadherin and alpha-, beta-, gamma-catenins in patients with bladder cancer: identification of gamma-catenin as a new prognostic marker of neoplastic progression in T1 superficial urothelial tumors.

Loss of intercellular adhesion facilitates tumor invasion. To clarify the relation between altered expression of cell adhesion molecules and progression of T1 superficial bladder tumors, 101 cases (71 T1 tumors, 30 T2/T3 tumors) were examined immunohistochemically for E-cadherin and alpha-, beta-, and gamma-catenins. A highly significant correlation was observed between the decreased expression of all molecules and increased TNM stage (P < .001). Univariate analysis, performed in cases of T1 tumors, revealed association of abnormal E-cadherin with beta-catenin diminution. Survival curves were established with the Kaplan-Meier method and analyzed according to clinical and histopathologic parameters using the log-rank test. Cox multivariate analysis revealed only gamma-catenin as an independent predictor of progression-free survival in patients with stage T1 bladder urothelial tumors. The characterization of T1 tumors that will progress could lead to the identification of patients who might benefit from surgery to avoid vesical muscle invasion and, consequently, metastasis.