Oncoprotein 18 is necessary for malignant cell proliferation in bladder cancer cells and serves as a G3-specific non-invasive diagnostic marker candidate in urinary RNA.

BACKGROUND: Urine-based diagnostics indicated involvement of oncoprotein 18 (OP18) in bladder cancer. In cell culture models we investigated the role of OP18 for malignant cell growth. METHODS: We analyzed 113 urine samples and investigated two human BCa cell lines as a dual model: RT-4 and ECV-304, which represented differentiated (G1) and poorly differentiated (G3) BCa. We designed specific siRNA for down-regulation of OP18 in both cell lines. Phenotypes were characterized by cell viability, proliferation, and expression of apoptosis-related genes. Besides, sensitivity to cisplatin treatment was evaluated. RESULTS: Analysis of urine samples from patients with urothelial BCa revealed a significant correlation of the RNA-ratio OP18:uroplakin 1A with bladder cancer. High urinary ratios were mainly found in moderately to poorly differentiated tumors (grade G2-3) that were muscle invasive (stage T2-3), whereas samples from patients with more differentiated non-invasive BCa (G1) showed low OP18:UPK1A RNA ratios. Down-regulation of OP18 expression in ECV-304 shifted its phenotype towards G1 state. Further, OP18-directed siRNA induced apoptosis and increased chemo-sensitivity to cisplatin. CONCLUSIONS: This study provides conclusive experimental evidence for the link between OP18-derived RNA as a diagnostic marker for molecular staging of BCa in non-invasive urine-based diagnostics and the patho-mechanistic role of OP18 suggesting this gene as a therapeutic target.

Destruction of stone extraction basket during an in vitro lithotripsy--a comparison of four lithotripters.

BACKGROUND: Various techniques are available for intracorporeal disintegration of renal and ureteral stones, among them ballistic lithotripsy, ultrasonic lithotripsy and laser lithotripsy. The therapeutic effectiveness of these devices has been sufficiently studied and compared. This does not apply, however, to the risk of destroying the stone basket. MATERIALS AND METHODS: The time until destruction of the wires of various baskets with use of four different lithotripsy devices (LithoClast, EMS; LithoRapid, Olympus; Calcuson 27610029, Storz; Vera Pulse, Coherent) was measured in a model closely aligned with the clinic. RESULTS: As expected, the direct application of laser pulses (wavelength 2.1 µm) irrespective of thickness and shape led to a melting of all wires of the stone extraction basket in less than 50 seconds (pulse energy: 800 mJ, pulse repetition rate: 8 hertz; fiber diameter: 365 µm). The purely kinetic functioning lithotripters (electrokinetic-ballistic and pneumatic-ballistic) were not able to destroy any wire within the set time limit of one minute. The sonotrode of the ultrasonic device, which is considered to be very tissue-conserving, separated all wires of baskets with a diameter of 1.8F (4 wires), 75% of baskets with a diameter of 2.5F (9 of 12), but only 8.3% of baskets with a diameter of 3.5F (1 of 12). Plaited wires demonstrated a good resistance (0 of 4) in comparison with the sonotrode. CONCLUSION: Our study consequently shows that in addition to the laser, the ultrasonic probe can also easily destroy nitinol (nickel titanium) baskets.

mTOR inhibitors show promising in vitro activity in bladder cancer and head and neck squamous cell carcinoma.

Bladder cancer and head and neck squamous cell carcinoma (HNSCC) are frequent but lack efficient therapies especially in advanced disease. Almost no studies on mTOR function and inhibition in these tumor entities have been reported. We examined the gene and protein expression levels of mTOR and its activated form (pmTOR) in three human bladder carcinoma cell lines (RT-4, T24, EJ28) and three HNSCC cell lines (PCI-1, PCI-13, BHY). Furthermore, the consequences of mTOR inhibition by mTOR-specific siRNAs and the mTOR inhibitor temsirolimus were analysed in vitro using immunohistochemical Ki-67 staining, mTOR and pmTOR western blot analysis, MTT assay, as well as cell cycle analysis with flow cytometry. Especially pmTOR protein expression levels showed marked differences between cell lines. siRNA transfection was associated with dose-dependent target protein reduction but not proliferation inhibition or apoptosis. On the contrary, temsirolimus significantly reduced cell viability and induced apoptosis and cell cycle arrest. According to these data, bladder cancer and HNSCC are promising tumor entities for mTOR inhibition with temsirolimus.

[Quality of life after radical cystectomy - an overview and analysis of a contemporary series]. / Lebensqualität nach radikaler Zystektomie - Ubersicht und Analyse einer aktuellen Serie.

OBJECTIVE: Published evidence does not support a clear advantage in quality of life for continent versus incontinent urinary diversion or vice versa. PATIENTS AND METHODS: We retrospectively assessed 61 patients after radical cystectomy with the EORTC-QLQ-C30 and -BLM30 instruments. Analysis was performed in dependence of age, sex, technique of urinary diversion and time-course of therapy. RESULTS: 36 patients had an incontinent and 20 patients a continent urinary diversion. Younger patients (p = 0.001) and those with a continent urinary diversion (p = 0.03) were found to have a statistically significant higher incidence of financial problems. Also patients with continent urinary diversion had significantly (p = 0.032) more problems in social integration. Furthermore, there were significant differences in social integration (p = 0.03) and emotional ability (p = 0.008) in the age-dependent analysis. Patients with a continent diversion had significantly more meteoristic problems (p = 0.007). CONCLUSION: This study also could not demonstrate any clear differences in dependence on the technique of urinary diversion. A good postoperative quality of life seems possible independent of age.

Metastases of squamous cell carcinoma of the head and neck show increased levels of nucleotide excision repair protein XPF in vivo that correlate with increased chemoresistance ex vivo.

Nucleotide excision repair (NER) is a key node of resistance of tumour cells to the anticancer drug cisplatin. Testicular germ cell tumours (TGCT) show exquisite sensitivity towards cisplatin, and this has been connected to low levels of the NER proteins ERCC1 and XPF. Tumours of some patients with advanced head and neck squamous cell carcinoma (HNSCC) regress well under cisplatin chemotherapy but prediction of responsiveness is poor. Little is known about the levels of ERCC1-XPF in HNSCC tissues and cell lines. We investigated mRNA and protein levels of ERCC1 and XPF in 13 HNSCC cell lines and seven testis tumour cell lines and examined the correlation between levels of ERCC1 and XPF and cellular resistance towards cisplatin. No significant difference in mRNA expression of either ERCC1 or XPF in the HNSCC cell lines compared to the testis tumour cell lines was observed. Significantly higher XPF protein levels were found in HNSCC cell lines compared to testis tumour cell lines resulting in cellular cisplatin resistance. The data indicate a contribution of XPF protein for the cisplatin resistance observed in HNSCC cell lines. Subsequently, XPF and ERCC1 protein expression was investigated in cancer tissue of 34 patients. XPF levels were significantly higher in metastases of HNSCC patients than in primary cancer tissue. These findings indicate a contribution of XPF protein for the observed chemoresistance in some HNSCC tissue. XPF protein may be a predictive marker for cisplatin responsiveness of metastases in HNSCC patients.

A robust methodology to study urine microRNA as tumor marker: microRNA-126 and microRNA-182 are related to urinary bladder cancer.

OBJECTIVES: MicroRNAs have been shown to be related to specific types of malignant cell growth. In case of urothelial bladder cancer (BCa), novel noninvasive diagnosis is particularly required and it is attractive to consider, as urine is an easily available source for molecular markers including RNA. In this context, we aimed to develop a clinically applicable and sensitive protocol for the preparation and molecular analysis of low molecular weight RNA from urine samples obtained from bladder cancer patients or healthy volunteers. MATERIALS AND METHODS: First, a method was developed for the preparation of low molecular weight RNA from a set of urine samples from different donor groups: (1) patients with low-grade BCa, (2) patients with high-grade BCa, (3) patients with urinary tract infections, (4) healthy donors; each n = 9. The RNA extracts were then used to monitor a number of 157 microRNA species by quantitative reverse transcriptase-polymerase chain reaction. Subsequently, those microRNAs that showed a higher abundance in urine samples from BCa patients were detected in an independent set of urine samples (n = 47). RESULTS: The significance and diagnostic usefulness of this methodology is reflected by the finding that the RNA ratio of microRNA-126:microRNA-152 enabled the detection of BCa from urine at a specificity of 82% and a sensitivity of 72%, with an area under the curve of 0.768 (95% confidence interval, 0.605-0.931). CONCLUSIONS: This study describes a novel, robust, and useful technology platform that is suitable to analyze small RNAs, including novel RNA-based tumor markers, in urine samples. A detailed technical analysis of this methodology provides new insights into the characteristics of urine microRNA such as composition and the donor-dependent variability.

Photodynamic diagnosis in non-muscle-invasive bladder cancer: a systematic review and cumulative analysis of prospective studies.

CONTEXT: The clinical benefit of photodynamic diagnosis (PDD) with 5-aminolevulinic acid or hexaminolevulinate in addition to white-light cystoscopy (WLC) in bladder cancer has been discussed controversially. OBJECTIVE: To assess in a systematic review the effect of PDD in addition to WLC on (1) the diagnosis and (2) the therapeutic outcome of primary or recurrent non-muscle-invasive bladder cancer investigated by cystoscopy or transurethral resection. EVIDENCE ACQUISITION: An electronic database search of Medline, Embase, the Cochrane Library, and CancerLit was undertaken, plus hand searching of relevant congress abstracts and urologic journals. Trials were included if they prospectively compared WLC with PDD in bladder cancer. The review process followed the guidelines of the Cochrane Collaboration. Two reviewers evaluated independently both trial eligibility and methodological quality and data extraction. EVIDENCE SYNTHESIS: The primary end point of diagnostic accuracy was additional detection rate. The primary end points of therapeutic outcome were residual tumour at second resection and recurrence-free survival (RFS). Seventeen trials were identified. Twelve diagnostic trials used WLC and PDD with the same patients. Seven reported results for the subgroup of patients with carcinoma in situ (CIS). Five randomised trials studied therapeutic outcome. The results were combined in random effects meta-analyses if end points, designs, and populations were comparable. Twenty percent (95% confidence interval [CI], 8-35) more tumour-positive patients were detected with PDD in all patients with non-muscle-invasive tumours and 39% (CI, 23-57) more when only CIS was analysed. Heterogeneity was present among diagnostic studies even when the subgroup of patients with CIS was investigated. Residual tumour was significantly less often found after PDD (odds ratio: 0.28; 95% CI, 0.15-0.52; p<0.0001). RFS was higher at 12 and 24 mo in the PDD groups than in the WLC-only groups. The combined p value of log-rank tests of RFS was statistically significant (0.00002). CONCLUSIONS: PDD detects more bladder tumour-positive patients, especially more with CIS, than WLC. More patients have a complete resection and a longer RFS when diagnosed with PDD.

In vivo studies on the availability and toxicity of antisense oligonucleotides in bladder cancer.

BACKGROUND: The urinary bladder is an ideal organ for topical treatment. A substantial number of bladder cancer patients are resistant to conventional intravesical therapy. In search of new agents, antisense oligonucleotides (AS-ON) may be interesting candidates. The availability and toxicity as well as the effectivity of AS-ON after intravesical instillation in different rodent models were examined. MATERIALS AND METHODS: Acute toxicity of AS-ON was tested by intravenous application (215-1,000 mg/kg body weight (bw)) in NMRI mice (n=30). The uptake and distribution of isotope-labelled AS-ON in bladder tissue was determined in Sprague Dawley rats (n=12) by radioactivity after intravesical application (2.5 mg/kg bw 3H-labelled AS-ON). Additionally, uptake and effectivity studies of AS-ON in tumors were performed in MB-49 bladder cancer-bearing C57/B16 mice (n=6) by immunohistochemistry and fluorescence microscopy. RESULTS: No systematic side-effects were noticed after intravenous application of physiological doses of AS-ON in NMRI mice. The mortality rate was 20% at the highest dose of 1,000 mg/kg bw. The highest AS-ON availability after intravesical application in rats was noticed in the bladder wall (12.3 microg/g), while the systemic concentration was low (1.1 microg/g). In fluorescence microscopy analysis, AS-ON were detected in the outer cells of the bladder wall and around vessels. AS-ON accumulated in the cytoplasm and in the nuclei. Immunohistochemical analysis demonstrated a reduction of the Ki-67 positivity after treatment with AS-ON (43%) compared to the untreated controls (58%). CONCLUSION: These preclinical experiments have shown that intravesical antisense oligonucleotides are safe and accumulate in the bladder and in bladder tumors, whereas systemic concentrations remain low. These data are the basis of a first clinical phase I study with intravesical instillation of Ki-67 antisense oligonucleotides.

Antisense-mediated inhibition of survivin, hTERT and VEGF in bladder cancer cells in vitro and in vivo.

Since cancer cells are characterised by multiple genetic alterations the single inhibition of one tumour- associated gene might not be sufficient as a therapeutic strategy. We examined the effects of a combined inhibition of survivin, human telomerase reverse transcriptase (hTERT) and vascular endothelial growth factor (VEGF) with antisense oligodeoxynucleotides (AS-ODNs) and small interfering RNAs (siRNAs) in EJ28 and 5637 bladder cancer (BCa) cells. Following verification of the uptake of intraperitoneally applied fluorescence-labelled AS-ODNs and siRNAs in subcutaneous BCa xenografts, the target-directed constructs were tested as single agents in SCID mice bearing subcutaneous EJ28. Simultaneous inhibition of two of the selected transcripts significantly enhanced cell viability reduction compared to the controls consisting of a target directed construct and an appropriate control construct without any homology to the human genome. The uptake of both antisense inhibitor types in the subcutaneous BCa was achieved even without a carrier. In vivo studies with 9 consecutive intraperitoneal injections with 20 mg/kg AS-ODNs or 4.6 mg/kg siRNAs revealed the biocompatibility of both antisense inhibitor types and showed anti-tumoural activity of the AS-ODNs used.

Prostate cancer vaccines: current status and future potential.

Standard systemic treatment of prostate cancer today is comprised of antihormonal and cytostatic agents. Vaccine therapy of prostate cancer is principally attractive because of the presence of tumor-associated antigens such as prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), prostate-specific membrane antigen (PSMA), and others. Most prostate cancer vaccine trials have demonstrated some activation of the immune system, limited clinical success, and few adverse effects.One strategy to overcome the problem of limited clinical success of vaccine therapies in prostate cancer could be strict patient selection. The clinical course of patients with prostate cancer (even in those with PSA relapse following surgery or radiotherapy with curative intention, or those with metastatic disease) can vary significantly. In patients with organ-confined prostate cancer, the most promising immunotherapeutic approach would be an adjuvant therapy following surgery or radiotherapy. Patients with PSA relapse following surgery or radiotherapy could also benefit from immunotherapy because tumor burden is usually low. However, most patients in prostate cancer vaccine trials had metastatic hormone-refractory prostate cancer (HRPC). High tumor burden correlates with immune escape phenomena. Nevertheless, 2 years ago, it was demonstrated, for the first time, that a tumor vaccine can prolong survival compared with placebo in patients with HRPC. This was demonstrated with the vaccine sipuleucel-T (APC-8015; Provenge), a mixture of cells obtained from the patient's peripheral blood by leukapheresis followed by density centrifugation and exposition. The Biologics License Application for this vaccine was denied by the US FDA in mid 2007, however, because the trial had failed to reach the primary endpoint (prolongation of time to tumor progression). Nevertheless, clinical trials with sipuleucel-T are ongoing, and the approach still looks promising. Another interesting approach is a vaccine made from whole tumor cells: GVAX. This vaccine is presently being studied in phase III trials against, and in combination with, docetaxel. The results from these trials will become available in the near future. Besides the precise definition of the disease status of patients with prostate cancer, combinations of vaccine therapy with radiotherapy, chemotherapy, and/or hormonal therapy are approaches that look promising and deserve further investigation.

Detailed technical analysis of urine RNA-based tumor diagnostics reveals ETS2/urokinase plasminogen activator to be a novel marker for bladder cancer.

BACKGROUND: The noninvasive detection of RNA tumor markers in body fluids represents an attractive diagnostic option, but diagnostic performance of tissue-derived markers is often poorer when measured in body fluids rather than in tumors. We aimed to develop a procedure for measurement of tumor RNA in urine that would minimize donor-dependent influences on the results. METHODS: RNA isolated from urinary cell pellet, cell-depleted fraction, and whole urine was quantified by reverse transcription quantitative-PCR. The donor-dependent influence of urine background on individual steps of the standardized procedure was analyzed using an external RNA standard. Using a test set of samples from 61 patients with bladder cancer and 37 healthy donors, we compared 4 putative RNA tumor markers identified in whole urine with 5 established, tissue-derived RNA tumor markers for the detection of bladder cancer. RESULTS: Of the markers analyzed by this system, the RNA ratio of v-ets erythroblastosis virus E26 oncogene homolog 2 (avian; ETS2) to urokinase plasminogen activator (uPA) enabled the most specific (100%) and sensitive (75.4%) detection of bladder cancer from whole urine, with an area under the curve of 0.929 (95% CI 0.882-0.976). CONCLUSIONS: The described methodology for RNA marker detection in urine appears to be clinically applicable. The ratio of ETS2 mRNA to uPA mRNA in urine is a potential marker for bladder cancer.

Drug evaluation: Therion's rV-PSA-TRICOM + rF-PSA-TRICOM prime-boost prostate cancer vaccine.

Therion Biologics Corp is developing PROSTVAC-VF-TRICOM, a prime-boost vaccine regimen that consists of a priming injection with a recombinant attenuated vaccinia virus expressing PSA and TRICOM (the company's proprietary triad of costimulatory molecules: ICAM-1, B7.1 and lymphocyte function-associated antigen-3), and a booster injection with a fowlpox virus expressing the same combination, for the potential treatment of prostate cancer. Phase II clinical trials are underway.

Recent improvements in the detection and treatment of nonmuscle-invasive bladder cancer.

In total, 70-80% of newly diagnosed bladder cancers are confined to the mucosa and staged as Ta, T1 or carcinoma in situ according to the 2002 tumor, lymph nodes and metastasis classification. The standard treatment for these nonmuscle-invasive bladder cancers is transurethral tumor resection with or without adjuvant intravesical chemotherapy or intravesical immunotherapy and subsequent follow-up. Diagnosis and follow-up of nonmuscle-invasive bladder cancer offers two main problems. First, approximately 10-20% of all tumors are not seen in standard cystoscopy. Additionally, frequently repeated follow-up cystoscopies are bothersome for the patient. As an adjunct to standard cystoscopy, fluorescence-guided cystoscopy has demonstrated significantly higher tumor detection rates and optimized patient treatment in recent Phase III studies. Second, routinely performed urine cytology is characterized by high specificity but low sensitivity. Today, several urine tests are available that may increase diagnostic accuracy and potentially prolong intervals of follow-up cystocopy. Owing to rather high recurrence rates after transurethral tumor resection in most tumors and high progression rates in poorly differentiated tumors, adjuvant intravesical chemotherapy or intravesical immunotherapy has gained widespread use in patients with nonmuscle-invasive bladder cancer. Only a few further immunomodulatory drugs, such as recombinant cytokines, have shown significant clinical effectiveness. Additional approaches, such as photodynamic therapy with different photosensitizers and thermotherapy in combination with intravesical chemotherapy, have been evaluated in Phase III studies.

Mesonephroid adenocarcinoma arising from mesonephroid metaplasia of the urinary bladder.

We present a rare case of mesonephroid adenocarcinoma arising from mesonephroid metaplasia of the urinary bladder. For the first time, the unique histopathologic features in this patient provide evidence for the theory that vesical mesonephroid adenocarcinoma might be a highly aggressive metaplastic variant of urothelial carcinoma that should be treated accordingly.

Value of clusterin immunoreactivity as a predictive factor in muscle-invasive urothelial bladder carcinoma.

OBJECTIVES: To determine whether clusterin immunoreactivity of muscle-invasive bladder carcinoma can predict disease-related survival of patients treated by radical cystectomy. METHODS: Multi-tissue arrays were constructed from 132 tumors and stained immunohistochemically using a mouse monoclonal antibody (clone 7D1). Positive clusterin staining was defined as immunoreactivity in more than 10% of tumor cells. We also studied tumor proliferation (Ki-67 antigen), p53, and Her2 expression. Immunoreactivity was compared with disease-related survival. Univariate and multivariate analyses were performed. RESULTS: Positive immunohistochemical clusterin expression was found in 25% of the tumors. On univariate analysis, clusterin immunoreactivity (P = 0.048), tumor stage (P = 0.011), nodal status (P = 0.0001), sex (P = 0.039), Ki-67 antigen index (P = 0.011), and Her2 expression (P = 0.020) were significantly associated with disease-related survival. On multivariate analysis, tumor stage (P = 0.01), nodal status (P = 0.0001), Ki-67 antigen (P = 0.0001), and Her2 expression (P = 0.001) were identified as significant independent predictive factors; clusterin expression missed the level of statistical significance by only a narrow margin (P = 0.058). CONCLUSIONS: Although clusterin immunoreactivity showed only a trend towards an independent prognostic relevance in this study, we conclude that it may be used, in addition to conventional and other immunohistochemical prognosticators, as a supplementary tool to provide more prognostic information in patients undergoing cystectomy for muscle-invasive bladder cancer.

Papillary urothelial bladder carcinoma associated with osteoclast-like giant cells.

We report the case of a papillary urothelial carcinoma associated with osteoclast-like giant cells. A 60-year old woman presented with hematuria. A papillary neoplasm was detected by cystoscopy and removed transurethrally. Histological examination revealed a papillary urothelial carcinoma (grade I) associated with multiple stromal giant cells, which displayed morphological, ultrastructural and immunohistochemical characteristics of osteoclast-like giant cells. The formation of osteoclast-like giant cells in association with urothelial bladder carcinoma is a rare event, of which only six cases have been reported in the Anglo-American literature. It may cause diagnostic problems because primary giant cell tumor, giant cell carcinoma and foreign body stromal reaction have to be considered. Immunohistochemistry and electron microscopy may help to rule out these differential diagnoses.

E-cadherin immunoreactivity correlates with recurrence and progression of minimally invasive transitional cell carcinomas of the urinary bladder.

E-cadherin is a transmembrane glycoprotein involved in intercellular adhesion. Abnormal (i.e., lost or decreased) expression of E-cadherin has been linked to invasiveness of many malignant tumors, including bladder carcinomas. To our knowledge, studies analyzing the prognostic impact of E-cadherin immunoreactivity especially in minimally invasive transitional cell bladder carcinomas (stage pT1) have not been published in the Anglo-American literature. In the present study, we immunostained 69 cases of pT1 transitional cell bladder carcinomas for E-cadherin using multitissue arrays. The results were compared with p53 and Ki-67 antigen immunoreactivity, clinicopathological parameters and the patients' outcome. E-cadherin immunoreactivity, which was found abnormal in 42% of cases, correlated significantly with substage (pT1a/pT1b; p=0.029) and p53 index (p=0.041) and tendentiously with Ki-67 antigen index (p=0.089) and age (p=0.07). By univariate Cox regression analysis, abnormal E-cadherin immunostaining correlated significantly (p=0.005) with early tumor recurrence, but not with early tumor progression (p=0.168). In a multivariate analysis, this parameter was identified, besides tumor grade (p=0.002), as an independent predictor of recurrence-free survival (p=0.016). Concerning tumor progression, age was identified as the single independent prognostic parameter (p=0.041), but E-cadherin immunoreactivity displayed a tendentious independent predictive value in this respect (p=0.071). We conclude from our data that immunohistochemical E-cadherin staining may provide additional prognostic information in patients with pT1 bladder carcinomas.

Expression of KIT (CD117) in renal cell carcinoma and renal oncocytoma.

OBJECTIVE: Overexpression of KIT (CD117), a tyrosine kinase receptor, has been reported in a variety of tumors, some of which are susceptible to therapy with imatinib mesylate. Our aim was to analyze KIT expression immunohistochemically in renal cell carcinomas (RCCs) and in oncocytomas. METHODS: Routinely processed, paraffin-embedded specimens from 61 RCCs and 13 renal oncocytomas were investigated immunohistochemically. Cytoplasmic and membrane-bound KIT staining of tumor cells was determined semiquantitatively. A subset of cases was additionally analyzed for point mutations of c-kit exon 17 by peptide nucleic acid-mediated nested polymerase chain reaction-clamping. RESULTS: All cases of oncocytomas and chromophobe RCCs showed membrane-bound KIT positivity, while about three-quarters of cases showed cytoplasmic reactivity. All other types of RCC were found KIT negative. Within the group of chromophobe RCCs, negative cytoplasmatic KIT reactivity was significantly correlated with advanced tumor stage (pT > or = 2; p = 0.036). Analysis of c-kit exon 17 revealed no 'gain-of-function' mutation like the codon 816 Asp-->Val mutation (D816V). CONCLUSIONS: KIT expression is a hallmark of oncocytoma and chromophobe RCC. Since all other types of RCC were found to be KIT negative, immunohistochemical KIT reactivity may be used as an additional diagnostic criterion to distinguish chromophobe RCC from other RCC types. KIT reactivity and the absence of c-kit mutation D816V in chromophobe RCC justify speculations that imatinib mesylate therapy could be effective in patients with advanced disease.

Protein expression and gene copy number analysis of topoisomerase 2alpha, HER2 and P53 in minimally invasive urothelial carcinoma of the urinary bladder--a multitissue array study with prognostic implications.

BACKGROUND: Due to their variable clinical course, there is a need for new prognostic parameters in minimally invasive (stage T1) bladder carcinomas. MATERIALS AND METHODS: Using multitissue arrays, protein expression and gene copy numbers of topoisomerase (TOP2alpha), HER2 and p53 were investigated by immunohistochemistry and by fluorescence in situ hybridization (FISH) in 73 T1 tumors. The results were compared with tumor recurrence and progression. RESULTS: The median TOP2alpha and p53 index was 21% (range, 3-59%) and 7% (range, 0-93%), respectively. HER2 overexpression (score 3+) was detected in 9 cases (12%). High TOP2alpha and p53 indices and HER2 overexpression were significantly associated with earlier tumor recurrence, but not with earlier tumor progression. While TOP2alpha and p53 gene amplification was detected in no case, 5 cases (8%) showed HER2 gene amplification, which was related to HER2 3+ score in 4 cases. Loss of TOP2alpha, HER2 and p53 gene was observed in 4 (8%), 8 (13%) and 6 cases (12%), respectively. By univariate analysis, TOP2alpha index (p=0.0267), HER2 score (p =0.028) and p53 index (p=0.0188) were significantly and loss of TOP2alpha gene (p=0.0575) tendentially correlated with tumor recurrence, while loss of HER2 gene (p=0.069) and loss of p53 gene (p=0.0587) were tendentially correlated with tumor progression. In a multivariate analysis, which also included tumor grade and T1 substage, TOP2alpha index (p=0.043) and p53 index (p=0.02) were identified as independent predictors of tumor recurrence and loss of p53 gene (p=0.012) and T1 substage (p=0.029) as independent predictors of tumor progression. CONCLUSION: Immuno-histochemical TOP2alpha and p53 staining as well as FISH analysis of p53 gene copy numbers and T1 substaging are helpful means of providing additional information on the biological behavior of T1 transitional cell carcinomas.

P16 immunoreactivity is an independent predictor of tumor progression in minimally invasive urothelial bladder carcinoma.

OBJECTIVE: To evaluate the prognostic impact of p16 immunoreactivity in minimally invasive transitional cell bladder carcinomas (stage T1). METHODS: Multi-tissue-arrays containing 73 samples of T1 bladder carcinomas were stained immunohistochemically for p16. Additionally, p53 and Ki-67 antigen expression were examined. A multivariate analysis including other prognostically relevant factors like tumor grade and sub-stage was performed. RESULTS: Loss of p16 expression occurred in 54% of cases and was significantly associated with reduced progression-free (p=0.018 by univariate analysis), but not with recurrence-free survival (p=0.341). Median Ki-67 antigen and p53 index were 51% (range, 1-93%) and 10% (range, 0-100%), respectively. Both indices correlated significantly (p=0.041 and p=0.024, respectively) with recurrence-free, but not with progression-free survival. Also tumor grade was significantly associated with tumor recurrence (p=0.006). By multivariate analysis, tumor grade (p=0.008) was identified as an independent predictor of tumor recurrence, whereas p16 expression (p=0.009) was identified as an independent predictor of tumor progression. CONCLUSION: According to our data, there is a significant correlation between loss of p16 expression and tumor progression in patients with minimally-invasive bladder cancer. Immunohistochemical p16 staining may therefore represent a useful tool of providing additional information on the clinical outcome of these patients.