Gender specific expression of tumor suppressor PKCd versus oncogenic PKCn in renal cell carcinoma

Tumor incidence for renal cell carcinoma is two-fold higher in males than in females. Members of the protein kinase C (PKC) gene family have been shown to be relevant for carcinogenesis. However, little is known about a possible gender specific role of PKC in renal cell carcinoma (RCC). In this study, we quantified expression of eleven PKC-isoforms in clear cell RCCs (ccRCC) and in the corresponding normal renal tissue. A possible association of PKC-isoforms with gender of the patients was examined. Tissue specimens of 27 patients, 14 males and 13 females, with ccRCC and of the corresponding normal renal tissue were examined. Expression of PKC-isoforms were detected by Western blot analysis and quantified by computer-aided integration. In ccRCCs, as well as in the corresponding normal renal tissue, all PKC-isoforms except PKCy and 0 were detectable. Clear associations with gender of the patients were observed: (i) PKCd was reduced in tumor tissue of female patients (p = 0.023), but not of male patients (p = 0.198). (ii) A 3.6-fold enhanced expression of the oncogene PKC? was found in tumor tissue of female compared to male patients (p = 0.049). Gender specific differences in PKCd as well as PKCn expression suggest that different molecular mechanisms are relevant for carcinogenesis of ccRCC in male and female patients. This may become important for classification and treatment of ccRCC

In renal cell carcinoma the PTEN splice variant PTEN-Δ shows similar function as the tumor suppressor PTEN itself

BACKGROUND: Loss of PTEN is involved in tumor progression of several tumor entities including renal cell carcinoma (RCC). During the translation process PTEN generates a number of splice variants, including PTEN-Δ. We analyzed the impact of PTEN-Δ in RCC progression. METHODS: In specimens of RCC patients the expression of PTEN-Δ and PTEN was quantified. The PTEN expressing RCC cell line A498 and the PTEN deficient 786-O cell line were stably transfected with the PTEN-Δ or PTEN transcript. In Caki-1 cells that highly express PTEN-Δ, this isoform was knocked down by siRNA. Cell migration, adhesion, apoptosis and signaling pathways activities were consequently analyzed in vitro. RESULTS: Patients with a higher PTEN-Δ expression had a longer lymph node metastasis free and overall survival. In RCC specimens, the PTEN-Δ expression correlated with the PTEN expression. PTEN-Δ as well as PTEN induced a reduced migration when using extracellular matrix (ECM) compounds as chemotaxins. This effect was confirmed by knockdown of PTEN-Δ, inducing an enhanced migration. Likewise a decreased adhesion on these ECM components could be shown in PTEN-Δ and PTEN transfected cells. The apoptosis rate was slightly increased by PTEN-Δ. In a phospho-kinase array and Western blot analyses a consequently reduced activity of AKT, p38 and JNK could be shown. CONCLUSIONS: We could show that the PTEN splice variant PTEN-Δ acts similar to PTEN in a tumor suppressive manner, suggesting synergistic effects of the two isoforms. The impact of PTEN-Δ in context of tumor progression should thus be taken into account when generating new therapeutic options targeting PTEN signaling in RCC

Strong Expression of Chemokine Receptor CXCR4 by Renal Cell Carcinoma Correlates with Advanced Disease

Diverse chemokines and their receptors have been associated with tumor growth, tumor dissemination, and local immune escape. In different tumor entities, the level of chemokine receptor CXCR4 expression has been linked with tumor progression and decreased survival. The aim of this study was to evaluate the influence of CXCR4 expression on the progression of human renal cell carcinoma. CXCR4 expression of renal cell carcinoma was assessed by immunohistochemistry in 113 patients. Intensity of CXCR4 expression was correlated with both tumor and patient characteristics. Human renal cell carcinoma revealed variable intensities of CXCR4 expression. Strong CXCR4 expression of renal cell carcinoma was significantly associated with advanced T-status (P = .039), tumor dedifferentiation (P = .0005), and low hemoglobin (P = .039). In summary, strong CXCR4 expression was significantly associated with advanced dedifferentiated renal cell carcinoma

Ultrasound-guided intramural inoculation of orthotopic bladder cancer xenografts: a novel high-precision approach

Orthotopic bladder cancer xenografts are essential for testing novel therapies and molecular manipulations of cell lines in vivo. Current xenografts rely on tumor cell inoculation by intravesical instillation or direct injection into the bladder wall. Instillation is limited by the lack of cell lines that are tumorigenic when delivered in this manner. The invasive model inflicts morbidity on the mice by the need for laparotomy and mobilization of the bladder. Furthermore this procedure is complex and time-consuming. Three bladder cancer cell lines (UM-UC1, UM-UC3, UM-UC13) were inoculated into 50 athymic nude mice by percutaneous injection under ultrasound guidance. PBS was first injected between the muscle wall and the mucosa to separate these layers, and tumor cells were subsequently injected into this space. Bioluminescence and ultrasound were used to monitor tumor growth. Contrast-enhanced ultrasound was used to study changes in tumor perfusion after systemic gemcitabine/cisplatin treatment. To demonstrate proof of principle that therapeutic agents can be injected into established xenografts under ultrasound guidance, oncolytic virus (VSV) was injected into UM-UC3 tumors. Xenograft tissue was harvested for immunohistochemistry after 23–37 days. Percutaneous injection of tumor cells into the bladder wall was performed efficiently (mean time: 5.7 min) and without complications in all 50 animals. Ultrasound and bioluminescence confirmed presence of tumor in the anterior bladder wall in all animals 3 days later. The average tumor volumes increased steadily over the study period. UM-UC13 tumors showed a marked decrease in volume and perfusion after chemotherapy. Immunohistochemical staining for VSV-G demonstrated virus uptake in all UM-UC3 tumors after intratumoral injection. We have developed a novel method for creating orthotopic bladder cancer xenograft in a minimally invasive fashion. In our hands this has replaced the traditional model requiring laparotomy, because this model is more time efficient, more precise and associated with less morbidity for the mice

Survival advantage of partial over radical nephrectomy in patients presenting with localized renal cell carcinoma

Background Partial nephrectomy (PN) preserves renal function and has become the standard approach for T1a renal cell carcinoma (RCC). However, there is still an ongoing debate as to which patients will actually derive greater benefit from partial than from radical nephrectomy (RN). The aim of this study was to retrospectively evaluate the impact of the type of surgery on overall survival (OS) in patients with localized RCC. Methods Renal surgery was performed in 4326 patients with localized RCC (pT ≤ 3a N/M0) at six German tertiary care centers from 1980 to 2010: RN in 2955 cases (68.3%), elective (ePN) in 1108 (25.6%), and imperative partial nephrectomy (iPN) in 263 (6.1%) cases. The median follow-up for all patients was 63 months. Kaplan-Meier and Cox regression analyses were carried out to identify prognosticators for OS. Results PN was performed significantly more often than RN in patients presenting with lower tumor stages, higher RCC differentiation, and non-clear cell histology. Accordingly, the calculated 5 (10)-year OS rates were 90.0 (74.6)% for ePN, 83.9 (57.5)% for iPN, and 81.2 (64.7)% for RN (p < 0.001). However, multivariate analysis including age, sex, tumor diameter and differentiation, histological subtype, and the year of surgery showed that ePN compared to RN still qualified as an independent factor for improved OS (HR 0.79, 95% CI 0.66-0.94, p = 0.008). Conclusion Even allowing for the weaknesses of this retrospective analysis, our multicenter study indicates that in patients with localized RCC, PN appears to be associated with better OS than RN irrespective of age or tumor size

The application of adjuvant autologous antravesical macrophage cell therapy vs. BCG in non-muscle invasive bladder cancer: a multicenter, randomized trial

<p>Abstract</p> <p>Introduction</p> <p>While adjuvant immunotherapy with Bacille Calmette Guérin (BCG) is effective in non-muscle-invasive bladder cancer (BC), adverse events (AEs) are considerable. Monocyte-derived activated killer cells (MAK) are discussed as essential in antitumoural immunoresponse, but their application may imply risks. The present trial compared autologous intravesical macrophage cell therapy (BEXIDEM^®) to BCG in patients after transurethral resection (TURB) of BC.</p> <p>Materials and methods</p> <p>This open-label trial included 137 eligible patients with TaG1-3, T1G1-2 plurifocal or unifocal tumours and ≥ 2 occurrences within 24 months and was conducted from June 2004 to March 2007. Median follow-up for patients without recurrence was 12 months. Patients were randomized to BCG or mononuclear cells collected by apheresis after ex vivo cell processing and activation (BEXIDEM). Either arm treatment consisted of 6 weekly instillations and 2 cycles of 3 weekly instillations at months 3 and 6. Toxicity profile (primary endpoint) and prophylactic effects (secondary endpoint) were assessed.</p> <p>Results</p> <p>Patient characteristics were evenly distributed. Of 73 treated with BCG and 64 with BEXIDEM, 85% vs. 45% experienced AEs and 26% vs. 14% serious AEs (SAE), respectively (p < 0.001). Recurrence occurred significantly less frequent with BCG than with BEXIDEM (12% vs. 38%; p < 0.001).</p> <p>Discussion</p> <p>This initial report of autologous intravesical macrophage cell therapy in BC demonstrates BEXIDEM treatment to be safe. Recurrence rates were significantly lower with BCG however. As the efficacy of BEXIDEM remains uncertain, further data, e.g. marker lesions studies, are warranted.</p> <p>Trial registration</p> <p>The trial has been registered in the ISRCTN registry <url>http://isrctn.org</url> under the registration number ISRCTN35881130.</p