Neuropilin-2 regulates androgen-receptor transcriptional activity in advanced prostate cancer

Aberrant transcriptional activity of androgen receptor (AR) is one of the dominant mechanisms for developing of castration-resistant prostate cancer (CRPC). Analyzing AR-transcriptional complex related to CRPC is therefore important towards understanding the mechanism of therapy resistance. While studying its mechanism, we observed that a transmembrane protein called neuropilin-2 (NRP2) plays a contributory role in forming a novel AR-transcriptional complex containing nuclear pore proteins. Using immunogold electron microscopy, high-resolution confocal microscopy, chromatin immunoprecipitation, proteomics, and other biochemical techniques, we delineated the molecular mechanism of how a specific splice variant of NRP2 becomes sumoylated upon ligand stimulation and translocates to the inner nuclear membrane. This splice variant of NRP2 then stabilizes the complex between AR and nuclear pore proteins to promote CRPC specific gene expression. Both full-length and splice variants of AR have been identified in this specific transcriptional complex. In vitro cell line-based assays indicated that depletion of NRP2 not only destabilizes the AR-nuclear pore protein interaction but also inhibits the transcriptional activities of AR. Using an in vivo bone metastasis model, we showed that the inhibition of NRP2 led to the sensitization of CRPC cells toward established anti-AR therapies such as enzalutamide. Overall, our finding emphasize the importance of combinatorial inhibition of NRP2 and AR as an effective therapeutic strategy against treatment refractory prostate cancer.

Abstract 521: The role of the E3 ubiquitin ligase Parkin in clear cell renal cell carcinoma

Introduction: The E3 ubiquitin ligase Parkin has been described in several cancer entities, including clear cell renal cell carcinoma (ccRCC). Decreased Parkin expression is associated with poor prognosis. We aimed to clarify the biological role of Parkin in ccRCC and to evaluate its expression in a clinically characterized renal cancer cohort.

Methods: We analyzed cell lines and clinically annotated patient material with qPCR (n=63), immunohistochemistry (n=262), LC-mass spectrometry and performed functional analyses in cell line models.

Results: We found that overexpression of Parkin results in a less aggressive phenotype in the clear cell renal cell carcinoma cell line 786-O indicated by lower migration and invasion. Mass spectrometry revealed decreased levels of several proteins in Parkin expressing cells. One of these proteins was cyclin kinase subunit 2 (CKS2). The introduction of a C431S mutation in the catalytic domain of the Parkin gene abolished the effect of decreased migration. In addition, knockdown of CKS2 in cells lacking Parkin caused decreased migration suggesting that the effect of Parkin is CKS2 mediated. Furthermore, the correlation of CKS2 and tumor grading is highly significant and high levels of CKS2 are associated with shorter survival times.

Conclusions: Parkin plays a major role in ccRCC biology, regulation cell migration and invasion, possibly exerted by CKS2 signaling. In consequence CKS2 appears to be an interesting prognostic biomarker in clear cell renal cell carcinoma and might also serve as a new therapy target.

Citation Format: Laura Kristin Esser, Vittorio Branchi, Farhad Shaker, Adrian Georg Simon, Carsten Stephan, Glen Kristiansen, Andreas Buness, Hubert Schorle, Marieta I. Toma. The role of the E3 ubiquitin ligase Parkin in clear cell renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 521.

CD103+ Tissue Resident T-Lymphocytes Accumulate in Lung Metastases and Are Correlated with Poor Prognosis in ccRCC

Clear cell renal cell carcinoma (ccRCC) is a highly immunogenic tumor with variable responses to immune checkpoint therapy. The significance of the immune cell infiltrate in distant metastases, their association with the immune infiltrate in the primary tumors and their impact on prognosis are poorly described. We hypothesized that specific subtypes of immune cells may be involved in the control of metastases and may have an impact on the prognosis of ccRCC. We analyzed the immune microenvironment in ccRCC primary tumors with distant metastases, paired distant metastases and non-metastasized ccRCC (n = 25 each group) by immunohistochemistry. Confirmatory analyses for CD8+ and CD103+ cells were performed in a large ccRCC cohort (n = 241) using a TCGA-KIRC data set (ITGAE/CD103). High immune cell infiltration in primary ccRCC tumors was significantly correlated with the development of distant tumor metastasis (p < 0.05). A high density of CD103+ cells in ccRCC was more frequent in poorly differentiated tumors (p < 0.001). ccRCCs showed high levels of ITGAE/CD103 compared with adjacent non-neoplastic tissue. A higher density of CD103+ cells and a higher ITGAE/CD103 expression were significantly correlated with poor overall survival in ccRCC (log rank p < 0.05). Our results show a major prognostic value of the immune pattern, in particular CD103+ cell infiltration in ccRCC, and highlight the importance of the tumor immune microenvironment.

Tumor Infiltrating Neutrophils Are Frequently Found in Adenocarcinomas of the Biliary Tract and Their Precursor Lesions with Possible Impact on Prognosis

Biliary tract cancer (BTC) is characterized by an intense stromal reaction and a complex landscape of infiltrating immune cells. Evidence is emerging that tumor-infiltrating neutrophils (TINs) have an impact on carcinogenesis and tumor progression. TINs have also been associated with outcomes in various solid malignant tumors but their possible clinical role in BTC is largely unknown. Tissue samples from patients with sporadic BTC ("spBTC" cohort, N = 53) and BTC in association with primary sclerosing cholangitis ("PSC-BTC" cohort, N = 7) were collected. Furthermore, tissue samples from 27 patients with PSC who underwent liver transplantation ("PSC-LTX" cohort) were investigated. All specimens were assessed for TIN density in invasive and precancerous lesions (biliary intraepithelial neoplasia, BilIN). Most spBTC showed low TIN density (LD, 61%). High TIN density (HD) was detected in 16% of the tumors, whereas 23% were classified as intermediate density (ID); the majority of both HD and ID groups were in T1-T2 tumors (83% and 100%, p = 0.012). TIN density in BilIN lesions did not significantly differ among the three groups. The HD group had a mean overall survival (OS) of 53.5 months, whereas the mean OS in the LD and ID groups was significantly shorter (LD 29.5 months vs. ID 24.6 months, log-rank p < 0.05). The results of this study underline the possible prognostic relevance of TINs in BTC and stress the complexity of the immune cell landscape in BTC. The prognostic relevance of TINs suggests a key regulator role in inflammation and immune landscape in BTC.

Cultivation of Clear Cell Renal Cell Carcinoma Patient-Derived Organoids in an Air-Liquid Interface System as a Tool for Studying Individualized Therapy

Clear cell renal cell carcinoma (ccRCC) is the most common renal cancer accounting for 80% of all renal cancers as well as the majority of renal cancer-associated deaths. During the last decade, the treatment paradigm for ccRCC has radically changed. In particular, the recent development of immune checkpoint inhibitors (ICI) has led to an increased overall survival in the metastatic setting. Moreover, novel immune therapies targeting the tumor microenvironment have been developed. In this rapidly evolving treatment landscape, precise tools for personalized cancer therapy are needed. Here, we collected fresh tissue from 42 patients who underwent surgical resection for renal cell carcinoma. Part of the tissue was used to obtain formalin-fixed, paraffin-embedded samples or RNA. The remaining tissue was minced and cultured in a collagen-based three-dimensional, air-liquid interface (ALI) culture system. The generated patient-derived tumor organoids (ALI PDOs) were characterized by immunohistochemistry staining and RNA sequencing to validate their close similarity to the matched tumor. Immune cells and stromal cells within the microenvironment could be identified. Finally, we treated 10 ALI PDOs with the commonly used targeted cancer drug cabozantinib or the ICI nivolumab. Interestingly, we observed varying responses of ALI PDOs to these treatments and future studies are needed to investigate whether the ALI PDO approach could inform about treatment responses in patients. In conclusion, this three-dimensional ccRCC culture model represents a promising, facile tool for monitoring tumor responses to different types of therapies in a controlled manner, yet, still preserves the key features of the tumor of origin.

ProstaTrend-A Multivariable Prognostic RNA Expression Score for Aggressive Prostate Cancer

BACKGROUND

Prostate cancer (PCa) is the most prevalent solid cancer among men in Western Countries. The clinical behavior of localized PCa is highly variable. Some cancers are aggressive leading to death, while others can even be monitored safely. Hence, there is a high clinical need for precise biomarkers for identification of aggressive disease in addition to established clinical parameters.

OBJECTIVE

To develop an RNA expression-based score for the prediction of PCa prognosis that facilitates clinical decision making.

DESIGN, SETTING, AND PARTICIPANTS

We assessed 233 tissue specimens of PCa patients with long-term follow-up data from fresh-frozen radical prostatectomies (RPs), from formalin-fixed and paraffin-embedded RP specimens and biopsies by transcriptome-wide next-generation sequencing and customized expression microarrays.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We applied Cox proportional hazard models to the cohorts from different platforms and specimen types. Evidence from these models was combined by fixed-effect meta-analysis to identify genes predictive of the time to death of disease (DoD). Genes were combined by a weighted median approach into a prognostic score called ProstaTrend and transferred for the prediction of biochemical recurrence (BCR) after RP in an independent cohort of The Cancer Genome Atlas (TCGA).

RESULTS AND LIMITATIONS

ProstaTrend comprising ∼1400 genes was significantly associated with DoD in the training cohort of PCa patients treated by RP (leave-one-out cross-validation, Cox regression: p=2e-09) and with BCR in the TCGA validation cohort (Cox regression: p=3e-06). The prognostic impact persisted after multivariable Cox regression analysis adjusting for Gleason grading group (GG) ≥3 and resection status (p=0.001; DoD, training cohort) and for GG≥3, pathological stage ≥T3, and resection state (p=0.037; BCR, validation cohort).

CONCLUSIONS

ProstaTrend is a transcriptome-based score that predicts DoD and BCR in cohorts of PCa patients treated with RP.

PATIENT SUMMARY

ProstaTrend provides molecular patient risk stratification after radical prostatectomy.

The Role of lncRNAs TAPIR-1 and -2 as Diagnostic Markers and Potential Therapeutic Targets in Prostate Cancer

In search of new biomarkers suitable for the diagnosis and treatment of prostate cancer, genome-wide transcriptome sequencing was carried out with tissue specimens from 40 prostate cancer (PCa) and 8 benign prostate hyperplasia patients. We identified two intergenic long non-coding transcripts, located in close genomic proximity, which are highly expressed in PCa. Microarray studies on a larger cohort comprising 155 patients showed a profound diagnostic potential of these transcripts (AUC~0.94), which we designated as tumor associated prostate cancer increased lncRNA (TAPIR-1 and -2). To test their therapeutic potential, knockdown experiments with siRNA were carried out. The knockdown caused an increase in the p53/TP53 tumor suppressor protein level followed by downregulation of a large number of cell cycle- and DNA-damage repair key regulators. Furthermore, in radiation therapy resistant tumor cells, the knockdown leads to a renewed sensitization of these cells to radiation treatment. Accordingly, in a preclinical PCa xenograft model in mice, the systemic application of nanoparticles loaded with siRNA targeting TAPIR-1 significantly reduced tumor growth. These findings point to a crucial role of TAPIR-1 and -2 in PCa.

Abstract B087: PARK2 expression reduces migration and invasion and deregulates metabolic pathways in ccRCC

PARK2 is an E3-ubiquitin-ligase, which plays an important role in mitophagy, a macroautophagy process that selectively degrades defective mitochondria. The significant downregulation of mRNA and protein levels in clear cell renal cell carcinoma (ccRCC) were shown to be associated with aggressive disease and poor clinical outcome (Toma et al., 2013). The aim of our study was to investigate the role of of PARK2 in ccRCC. First, we transduced the ccRCC cell line 786-O with a PLVX-EF1a-PARK2-IRES-mcherry construct to overexpress PARK2. Subsequently, we performed functional assays, analyzed the mitochondria and mitochondrial respiration, and RNA-Sequencing. While apoptosis, cell cycle and cell proliferation remained unaffected, we found a marked reduction of migration and invasion in PARK2 overexpressing cells compared to wt controls. PARK2 is involved in the degradation of damaged mitochondria during mitophagy, therefore, we investigated the amount of active and total mitochondria and found more active mitochondria in the PARK2 clones. The overall amount of mitochondria was unchanged. To verify the results and get a further insight into the functionality of the mitochondria mitochondrial respiration was analyzed. As expected, the mitochondrial respiration of the PARK2 clones was upregulated. In addition, we observed a general shift towards metabolic upregulation in 786-O cells expressing PARK2. To find specific pathways affected by the expression of PARK2, we performed RNA Sequencing. Several metabolic pathways were deregulated in the cells expressing PARK2 compared to wt controls. We were able to identify several genes being downregulated in transgenic wild type cells that play a role in the epithelial-to-mesenchymal transition underlining our phenotypic findings of invasion and migration. In conclusion, PARK2 has an impact on the aggressiveness of the disease, the health of the mitochondria and effects a deregulation of metabolic pathways. Lately, several groups reported on the connection between migration/invasion and metabolic changes (Kenny et al., 2019; Yizhak et al., 2014; Gaude and Frezza; 2016, Yao et al., 2018) suggesting a potential link between these two events. Our study adds additional proof towards that link, nevertheless, further research needs to be conducted to identify if these two events are indeed interconnected and dependent on each other. Literature Gaude E and Frezza C. Tissue-specific and convergent metabolic transformation of cancer correlates with metastatic potential and patient survival. Nat Commun. 7:13041. 2016. Kenny TC et al. Mitohormesis Primes Tumor Invasion and Metastasis. Cell Rep. 27(8):2292-2303. 2019. Toma MI et al. PARK2 and PACRG are commonly downregulated in clear-cell renal cell carcinoma and are associated with aggressive disease and poor clinical outcome. Genes Chromosomes Cancer. 52(3):265-73. 2013. Yao L, Guo X, Gui Y. Acetyl-CoA Synthetase 2 Promotes Cell Migration and Invasion of Renal Cell Carcinoma by Upregulating Lysosomal Associated Membrane Protein 1 Expression. Cell Physiol Biochem. 45(3):984-992. 2018. Yizhak K et al. A computational study of the Warburg effect identifies metabolic targets inhibiting cancer migration. Mol Syst Biol. 10:744. 2014.

Citation Format: Laura K Eßer, Lena Arévalo, Glen Kristiansen, Hubert Schorle, Marieta I Toma. PARK2 expression reduces migration and invasion and deregulates metabolic pathways in ccRCC [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B087. doi:10.1158/1535-7163.TARG-19-B087

Abstract 3113: Expression of autophagy- and mitophagy-related genes in clear cell renal cell carcinoma

Objectives: First objective of this study was to establish primary cell cultures from renal cell carcinoma (RCC). Second objective was to analyze mRNA and protein expression of PINK1, PARK2, PACRG and a-Synuclein, genes involved in cell survival, apoptosis and mitophagy.

Methods: Tumor and non-neoplastic tissue from 15 patients undergoing surgery for clear cell renal cell carcinoma (ccRCC, n=9), papillary renal cell carcinoma (pRCC, n=3) as well as three retroperitoneal metastases (two clear cell, one papillary type) were obtained. After tissue digestion and filtration malignant and non-malignant cells were cultivated in two different media in order to establish an optimized cultivation procedure. DNA and RNA were extracted and immunohistochemical analyses (IHC) and qPCR from cultivated cells were performed for VHL and CAIX to verify tumor histotype. RNA was isolated from fresh-frozen primary ccRCC samples and corresponding non-malignant tissues from 50 patients (30 male, 20 female). Expression of PINK1, PARK2, PACRG and a-synuclein was measured by qPCR in the cultivated ccRCC cell lines as well as in the patient samples.

Results: All tumor specimens were successfully cultivated to first confluence. Six out of nine ccRCC cell lines and all other tumor specimens could be passaged more than two times. Cultivated RCC cells showed protein expression matching to their tumor of origin in IHC analyses, confirming tumor identity. QPCR demonstrated VHL expression downregulated or lost in all ccRCC cell lines and CA9 highly upregulated in most cases, which is both typical for ccRCC. The mRNA expression of PINK1, PARK2 and PACRG was downregulated in ccRCC cultures as well as in the 50 patient tumors in comparison to normal tissue. A-synuclein expression was highly variable.

Conclusions: We successfully established primary cell cultures from various renal tumor entities suitable for further investigation. Loss of PACRG and PARK2 are common events in ccRCC. PACRG and PARK2 might function as tumor suppressors in ccRCC and their loss may be involved in tumor progression as reported before for other tumor entities. Further investigation of PINK1, PARK2 and PACRG might allow new therapeutic approaches.

Citation Format: Adrian G. Simon, Joerg Ellinger, Yuri Tolkach, Stefan C. Mueller, Glen Kristiansen, Marieta I. Toma. Expression of autophagy- and mitophagy-related genes in clear cell renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3113.

Abstract 1278: Accumulation of tolerogenic human 6-sulfo LacNAc+ dendritic cells in renal cell carcinoma is associated with poor prognosis

6-sulfo LacNAc+ (slan) DCs, representing a myeloid human blood DC subset, produce various proinflammatory cytokines, display cytotoxic activity and efficiently stimulate natural killer (NK) cells and T lymphocytes. Recent studies demonstrated that slanDCs accumulate in metastatic tumor-draining lymph nodes from cancer patients, indicating that slanDCs may contribute to antitumor immunity.

We constructed tissue microarrays from primary clear-cell renal cell carcinomas (ccRCC) and paired non-neoplastic renal tissues from 265 patients who underwent radical/partial nephrectomy in the Department of Urology, University Clinic, TU Dresden. The slanDCs were identified by immunohistochemistry using a DD2 antibody, developed in the Institute of Immunology, TU Dresden. Freshly prepared tumor-infiltrating cells from 10 specimens were used for phenotypic characterization by flow cytometry. The effects of slanDCs and T-lymphocytes isolated from freshly prepared peripheral blood mononuclear cells on ACHN, CAKI-1 and on two native ccRCC cell lines were assessed by flow-cytomtery, proliferation assays. The frequency of slanDCs in ccRCC and paired non-neoplastic renal tissues were correlated with the clinico-pathological characteristics of patients. SlanDCs were detectable in the majority of primary tumors (93.2%), metastatic lymph nodes (87.5%) and distant metastases (85.1%). A significantly (p&lt;0.001) higher number of slanDCs were detected in primary ccRCC tissues (mean: 3.74 slanDC/mm2, range: 0-19.82 slanDC/mm2) compared to tumor-free tissues (mean: 1.19 slanDC/mm2, range: 0-9.9 slanDC/mm2). A higher density of slanDCs in ccRCC tissues was significantly correlated with a higher grading and stage of the primary tumor (p = 0.001 and p = 0.006 respectively), as well as with lymph node- or distant metastases (p = 0.039 and p&lt;0.001, respectively). Remarkably, a higher density of slanDCs was significantly correlated with a reduced progression-free, tumor-specific or overall survival of ccRCC patients. Freshly prepared ccRCC-infiltrating slanDCs expressed HLA-DR and low densities of CD86, but CD40, CD80, CD83 and CCR7 could not be detected. Whereas the proinflammatory cytokines TNF-α and IL-12 were not found, a proportion of slanDCs showed expression of the anti-inflammatory cytokine IL-10. Further studies revealed that primary ccRCC cells efficiently impair the capacity of slanDCs to stimulate CD4+ and CD8+ T-cell proliferation and Th1 programming. In addition, ccRCC cells significantly inhibited slanDC-mediated NK cell activation.

These findings indicate that higher slanDC numbers in ccRCC tissues are associated with poor prognosis. The induction of a tolerogenic phenotype in slanDCs leading to an insufficient activation of innate and adaptive antitumor immunity may represent a novel immune escape mechanism of ccRCC.

Citation Format: Marieta I. Toma, Rebekka Wehner, Anja Kloß, Kati Erdmann, Susanne Fuessel, Barbara Seliger, Dorothee Brech, Elfriede Noessner, Knut Schaekel, Manfred Wirth, Gustavo Baretton, Marc Schmitz. Accumulation of tolerogenic human 6-sulfo LacNAc+ dendritic cells in renal cell carcinoma is associated with poor prognosis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1278. doi:10.1158/1538-7445.AM2015-1278

Lack of ephrin receptor A1 is a favorable independent prognostic factor in clear cell renal cell carcinoma

The EPH receptor tyrosine kinases and their cell-bound ligands, the ephrins, have been shown to be associated with cancer development and progression. In this study, mRNA and protein expression of the receptors EPHA1 and EPHA2 as well as of their ligand EFNA1 and their prognostic relevance in clear cell renal cell carcinoma was evaluated. Gene expression was measured in 75 cryo-preserved primary tumors and matched non-malignant renal specimens by quantitative PCR. Protein expression was analyzed by immunohistochemistry on tissue microarrays comprising non-malignant, primary tumors and metastatic renal tissues of 241 patients. Gene and protein expression of all three factors was altered in tumor specimens with EPHA1 and EPHA2 being generally diminished in tumors compared to normal renal tissue, whereas EFNA1 was commonly elevated. A positive EPHA1 and EPHA2 protein staining as well as a low EFNA1 protein level were significantly linked to more aggressive tumor features, but only a positive EPHA1 immunoreactivity was significantly associated with poor survival. In subgroup analyses, EPHA1 and EPHA2 protein levels were significantly higher in metastatic than in primary lesions. Patients with EPHA1/EPHA2-positive tumors or with tumors with positive EPHA1 and low EFNA1 immunoreactivity had the shortest survival rates compared to the respective other combinations. In a multivariate model, EPHA1 was an independent prognostic marker for different survival endpoints. In conclusion, an impaired EPH-ephrin signaling could contribute to the pathogenesis and progression of clear cell renal cell carcinoma.

PARK2 and PACRG are commonly downregulated in clear-cell renal cell carcinoma and are associated with aggressive disease and poor clinical outcome

PARK2 is an E3 ligase, known to be involved in ubiquitination of several proteins and to play a role in neuronal protection. The gene PARK2 and its potentially co-regulated gene PACRG have been previously found to be deleted in clear-cell renal cell carcinomas (ccRCCs). The aim of our study was to evaluate the mRNA and protein expression of PARK2 and PACRG in a large cohort of ccRCC, and to investigate their association with outcome. The expression of both genes was measured by quantitative PCR in 94 primary ccRCCs and autologous nonmalignant kidney tissues. PACRG and PARK2 protein expression was determined immunohistochemically using tissue microarrays comprising 133 ccRCCs. The mRNA and protein expression of PARK2 and PACRG was significantly downregulated in ccRCCs compared with nonmalignant tissues. Low levels of PARK2 mRNA were associated with high-grade ccRCC and lymph node metastasis. Patients with low PARK2 mRNA levels showed a higher tumor-specific mortality rate and a shorter overall survival (OS) than those with high PARK2 expression. Patients without PACRG mRNA expression in the tumor had a shorter disease-free survival and OS than those with tumors expressing PACRG. In multivariate analyses, neither PARK2 nor PACRG expression were independent prognostic factors. The protein expression of PARK2 and PACRG was significantly downregulated in ccRCCs (82.8, and 96.9%, respectively), but no association with clinical outcome was noticed.

CD31, EDNRB and TSPAN7 are promising prognostic markers in clear-cell renal cell carcinoma revealed by genome-wide expression analyses of primary tumors and metastases

Currently used clinicopathological parameters are insufficient for a reliable prediction of metastatic risk and disease-free survival (DFS) of patients with clear-cell renal cell carcinoma (ccRCC). To identify prognostic genes, the expression profiles of primary ccRCC obtained from patients with different DFS--eight synchronously, nine metachronously and seven not metastasized tumors--were determined by genome-wide expression analyses. Synchronously and metachronously metastasized primary ccRCC differed in the expression of 167 genes. Thirty-six of these genes were also differentially expressed in synchronously vs. metachronously developed pulmonary metastases analyzed in a previous study. Because of their DFS-associated deregulation that is concordant in metastases and primary ccRCC, these genes are potentially functionally involved in metastatic tumor growth and are also prognostically useful. A prognostic impact was confirmed for the genes CD31, EDNRB and TSPAN7 at the mRNA level (n=86), and for TSPAN7 at the protein level (n=106). Patients with a higher gene expression of EDNRB or TSPAN7, or with TSPAN7-positive vessels in both cores investigated on tissue microarrays had a significantly longer DFS and tumor-specific survival (TSS). Patients with a higher CD31 gene expression showed a significantly longer TSS. EDNRB was an independent prognostic marker for the DFS. CD31, EDNRB and TSPAN7 had an independent impact on the TSS. In summary, comparative analysis of primary tumors and metastases is appropriate to identify independent prognostic markers in ccRCC. Gene expression of CD31 and EDNRB, and endothelial TSPAN7 protein level are potentially useful to improve outcome prediction because of their independent prognostic impact.

Correlation of centrosomal aberrations with cell differentiation and DNA ploidy in prostate cancer

OBJECTIVE

To analyze the centrosomal abnormalities in correlation with DNA ploidy and clinicopathologic data in prostate cancer.

STUDY DESIGN

Formalin-fixed, paraffin-embedded material from 63 prostate cancers (PCa) and 10 normal control cases were studied. Centrosomal features (number, area and shape) were assessed by immunohistochemistry with a gamma-tubulin monoclonal antibody. For each case centrosomal features were assessed in 100 cells, and the mean and median value was calculated. Statistical analysis was done by Student's t test, Mann-Whitney U test and multivariate analysis. The colocalization of gamma-tubulin and pericentrin at the centrosome was proven by double immunofluorescence staining. The DNA ploidy status was analyzed on Feulgen-stained, disintegrated paraffin sections using the OPTIMAS-based work station (Media Cybernetics, Silver Spring, Maryland, U.S.A.).

RESULTS

PCa cells showed centrosomal aberrations when compared to normal tissue. Poorly differentiated PCa showed more centrosomal abnormalities than well differentiated PCa (p < 0.05). Twenty-seven percent PCa were DNA nondiploid and 73% PCa were DNA diploid, respectively, just as all control specimens. DNA nondiploid status correlates with centrosomal abnormalities (p < 0.05). pT4 tumors showed significantly more centrosomes than pT2 and pT3 tumors (p < 0.05).

CONCLUSION

Changes in centrosome features indicate disturbed centrosome function and are significantly correlated with loss of differentiation in PCa. This is the first image analysis study of centrosome features in PCa, confirming that centrosome defects are involved in the acquisition of chromosomal aberrations in PCa.

[DNA methylation on urinalysis and as a prognostic marker in urothelial cancer of the bladder]

INTRODUCTION AND OBJECTIVES

Detection of promoter hypermethylation has been proposed as a promising tool for cancer diagnosis and as a prognostic marker in various cancers. We studied the versatility of DNA methylation for noninvasive diagnosis and as a prognostic marker for non-muscle-invasive bladder carcinoma.

METHODS

Tumor specimens were microdissected and DNA was extracted from 105 paraffin-embedded paraffin specimens from patients undergoing transurethral resection for non-muscle-invasive bladder carcinoma. Urine specimens were collected from patients undergoing cystectomy for bladder cancer and from healthy volunteers. Methylation status was assessed with the real-time quantitative methylation-sensitive PCR (MethyLight). We checked a panel of 20 cancer-associated genes (p14ARF, p16 CDKN2A, STAT-1, SOCS-1, DR-3, DR-6, PIG-7, BCL-2, H-TERT, BAX, EDNRB, DAPK, RASSF-1A, FADD, TMS-1, E-CADHERIN, ICAM-1, TIMP-3, MLH-1, COX-2) for DNA methylation.

RESULTS

Follow-up data were available in 95 of 105 patients (91.4%). A tumor recurrence was observed in 26 patients (27.3%). We could identify six genes (SOCS-1, STAT-1, BCL-2, DAPK, TIMP-3, E-cadherin), where methylation was associated with tumor recurrence. In Kaplan-Meier analysis, TIMP-3 showed a significant association with recurrence-free survival. Methylation of TIMP-3 predicted prolonged disease-free interval. Regarding urinalysis we could identify a pattern of methylation markers including DAPK, BCL-2, and H-TERT that yielded a sensitivity of 81.1% with a specificity of 100% in a cancer-free control population

CONCLUSIONS

We present data on the clinical usefulness of methylation analysis in bladder carcinoma. Our data confirm that methylation analysis is a promising tool for bladder cancer diagnosis and prognosis.

The role of the endothelin axis and microvessel density in bladder cancer - correlation with tumor angiogenesis and clinical prognosis

Endothelin-1 (ET-1) and its receptors, entothelin-A (ETAR) and endothelin-B (ETBR), commonly referred to as the endothelin (ET)-axis, are involved in tumor biology and growth. We investigated the effects of the ET-axis on microvessel density (MVD) and the clinicopathological parameters of patients with invasive bladder cancer. Paraffin tumor sections of 120 patients who had undergone radical cystectomy were assessed immunohistochemically using mono- and polyclonal antibodies for ET-1, ETAR, ETBR and CD34 (MVD). Staining intensities were analyzed semiquantitatively and the MVD was calculated as vessels per field. The results were correlated with various pathological and clinical factors, as well as with disease-free and overall survival. Transitional cell carcinomas (MVD=23.7) were better vascularized than squamous cell carcinomas (MVD=17.8, p=0.04). Organ-confined tumors (MVD=32.2) were better vascularized than T3- and T4-tumors (MVD=21.2, p=0.02) and ET-1 was overexpressed in this subgroup (p=0.027). Patients with metastatic regional lymph nodes (MVD=20.9) tended to have less MVD than patients without regional lymph node metastases (MVD=24.1) (p=0.15). The account of MVD did not reveal any significant differences in disease-free or overall survival. Organ-confined tumors and ET-1 overexpression are associated with upregulated microvessel density. These results suggest that MVD and ET-1 could be considered good prognostic factors.

Prognostic relevance of methylation markers in patients with non-muscle invasive bladder carcinoma

There is increasing evidence for the role of epigenetic gene silencing in superficial bladder cancer. The aim of the current study was to investigate the prognostic value of epigenetic alterations in patients with non-muscle invasive bladder carcinoma. We checked the methylation status of 20 cancer associated genes (p14ARF, p16 CDKN2A, STAT-1, SOCS-1, DR-3, DR-6, PIG-7, BCL-2, H-TERT, BAX, EDNRB, DAPK, RASSF-1A, FADD, TMS-1, E-Cadherin, ICAM-1, TIMP-3, MLH-1, COX-2) for DNA methylation. We analysed microdissected tumour samples from 105 consecutive patients with primary non-muscle invasive bladder carcinoma. Quantitative methylation analysis of CpG sites in the promoter region of the genes was performed with methylation sensitive quantitative real time PCR ('Methylight'). Univariate analysis for association with tumour recurrence was carried out with the Kaplan-Meier analysis and the log-rank test. Follow-up data were available in 95/105 patients (91.4%). A tumour recurrence was observed in 26 patients (27.3%). We could identify six genes (SOCS-1, STAT-1, BCL-2, DAPK, TIMP-3, E-Cadherin), where methylation was associated with tumour recurrence. In Kaplan-Meier analysis, TIMP-3 showed a significant association with recurrence free survival. Methylation of TIMP-3 predicted prolonged disease free interval. In this study, we report a comprehensive analysis on prognostic relevance of gene methylation in non-muscle invasive bladder cancer. We identified one gene (TIMP-3) where methylation was associated with a more favourable outcome. Our data strongly support the usefulness of gene methylation as a prognostic marker in patients with non-muscle invasive bladder cancer.

Detection of methylated apoptosis-associated genes in urine sediments of bladder cancer patients

PURPOSE

There is increasing evidence for a fundamental role for epigenetic silencing of apoptotic pathways in cancer. Changes in DNA methylation can be detected with a high degree of sensitivity, so we used the MethyLight assay to determine how methylation patterns of apoptosis-associated genes change during bladder carcinogenesis and whether DNA methylation could be detected in urine sediments.

EXPERIMENTAL DESIGN

We analyzed the methylation status of the 5' regions of 12 apoptosis-associated genes (ARF, FADD, TNFRSF21, BAX, LITAF, DAPK, TMS-1, BCL2, RASSF1A, TERT, TNFRSF25, and EDNRB) in 18 bladder cancer cell lines, 127 bladder cancer samples, and 37 samples of adjacent normal bladder mucosa using the quantitative MethyLight assay. We also analyzed the methylation status in urine sediments of 20 cancer-free volunteers and 37 bladder cancer patients.

RESULTS

The 5' regions of DAPK, BCL2, TERT, RASSFIA, and TNFRSF25 showed significant increases in methylation levels when compared with nonmalignant adjacent tissue (P < or = 0.01). Methylation levels of BCL2 were significantly associated with tumor staging and grading (P < or = 0.01), whereas methylation levels of RASSF1A and ARF were only associated with tumor stage (P < or = 0.04), and TERT methylation and EDNRB methylation were predictors of tumor grade (P < or = 0.02). To investigate clinical usefulness for noninvasive bladder cancer detection, we further analyzed the methylation status of the markers in urine samples of patients with bladder cancer. Methylation of DAPK, BCL2, and TERT in urine sediment DNA from bladder cancer patients was detected in the majority of samples (78%), whereas they were unmethylated in the urine sediment DNA from age-matched cancer-free individuals.

CONCLUSIONS

Our results indicate that methylation of the 5' region of apoptosis-associated genes is a common finding in patients with bladder carcinoma. The ability to detect methylation not only in bladder tissue, but also in urine sediments, suggests that methylation markers are promising tools for noninvasive detection of bladder cancers. Our results also indicate that some methylation markers, such as those in regions of RASSF1A and TNFRSF25, might be of limited use for detection because they are also methylated in normal bladder tissues.

Expression of Maspin in non-muscle invasive bladder carcinoma: correlation with tumor angiogenesis and prognosis

OBJECTIVES

Maspin is a member of the serpin (serine protease inhibitor) family and has been shown to be a suppressor of tumor growth and an inhibitor of angiogenesis as well as metastasis in several types of tumors. We studied expression patterns of Maspin in pTa/pT1 urothelial carcinoma of the bladder and compared them with microvessel density (MVD) for two vascular markers (CD34 and CD105) and correlated the findings with clinical outcome.

MATERIAL AND METHODS

We investigated tumor samples of 110 patients undergoing transurethral resection for pTa/pT1 bladder carcinoma (pTa, n=84; pT1, n=26; grade 1, n= 22; grade 2, n= 81; grade 3, n=7). Immunohistochemical studies were performed using the monoclonal antibodies, anti-human Maspin (NCL Maspin), anti-CD34 Class II and anti-CD105. Maspin expression level was classified according to the staining intensity (- to +++). The blood vessels (CD34) and specifically proliferating blood vessels (CD105) were counted as vessels per field (microvessel density, MVD).

RESULTS

Of the 110 tumors, 27 showed a negative immunostaining for Maspin, 46 tumors stained +, 29 stained ++, and 8 stained +++. Maspin expression correlated inversely with CD34 reactivity. In tumors with loss of or only weak Maspin expression, the MVD for CD34 was 21.7 vessels per field, and 4.2 vessels per field for proliferating vessels (CD105), whereas Maspin-positive tumors had an MVD of 17.7 vessels per field (CD34), and of 6.0 vessels per field (CD105). Complete follow-up data are available in 92 patients. After a median follow-up of 25 months, 18 of the 92 patients (19.6%) had tumor recurrences. Tumors with decreased Maspin expression (-/+) had a shorter disease-free interval (23 months) than patients with stronger Maspin (++/+++) expression (29 months), whereas a Kaplan-Meier analysis and the log-rank test showed no significant difference in disease-free survival between the patients.

CONCLUSION

The clinical importance of Maspin has been mainly investigated regarding tumor progression or metastasis. We found a decreased Maspin expression in a large portion of pTa/pT1 bladder tumors. Even if patients with decreased Maspin expression have a slightly shorter disease-free survival Maspin does not appear to be a promising prognostic marker.

Comparison of the ImmunoCyt test and urinary cytology with other urine tests in the detection and surveillance of bladder cancer

Despite several new urine markers urinary cytology remains the gold standard for the non-invasive detection of bladder carcinoma. The use of monoclonal antibodies against tumor associated antigens offers a promising approach to improve urinary cytology. The aim of this study was to compare fluorescence immunocytology (ImmunoCyt/Ucyt+ test), alone and in combination with the conventional cytology, with other urine markers. Urine samples from 126 patients undergoing cystoscopy were included in the study. Among them, 42 patients had urothelial carcinoma, two dysplasia, two other malignancies, and 78 had no evidence of bladder cancer. Urine samples were taken before any manipulation. We used the ImmunoCyt test and Papanicolaou staining for conventional cytology. The ImmunoCyt slides were examined under a fluorescence microscope. Evaluations of the tests were blinded to clinical and pathological data and were carried out by three independent observers. The results of cytology and ImmunoCyt were compared with the BTAstat, NMP22, Lewis X, 486p3/12, and Urovision tests. The sensitivity for the ImmunoCyt test was 78.3% and for conventional cytology 84.6%. The combination of ImmunoCyt and cytology showed a sensitivity of 89.1%. The specificity was 73.8% for the ImmunoCyt alone, 80.0% for the cytology, and 72.5% for the combination of ImmunoCyt and cytology. Sensitivities for the other tests were 68.8% for (FISH), 66.6% (BTA-Stat), 68.8% (486p3/12), 95.5% (Lewis X), and 71.1% for (NMP22). Specificity was 89.1% for (FISH), 78.2% (BTA-Stat), 76.4% (486p3/12), 32.8% (Lewis X), and 65.5% for (NMP22). Urinary cytology can be improved by immunostaining with monoclonal antibodies against tumor-associated antibodies. The combination of ImmunoCyt with conventional cytology offers a superior sensitivity to other commercial tests. The ImmunoCyt test provides a useful supplement to urinary cytology in the diagnosis of bladder cancer.

Comparison of multitarget fluorescence in situ hybridization in urine with other noninvasive tests for detecting bladder cancer

OBJECTIVES

To present a single-centre study investigating aneuploidy at chromosomes 3, 7, 17 and 9p21 (e.g. loss at 9p21) using a multitarget fluorescence in situ hybridization (FISH) system, as identifying genetic alterations in urine specimens is a promising approach for the noninvasive detection of bladder cancer.

PATIENTS AND METHODS

Urine samples from 103 patients were evaluated, including those from 46 with histologically confirmed urothelial carcinoma, two with other urological malignancies, and 55 who acted as controls. The urine samples were taken before any manipulation. The validity of FISH (Urovision, Vysis, Downers Grove, Ill, USA) was compared with other noninvasive urine tests, including the BTA-Stat test, the nuclear matrix protein (NMP)-22 test, and immunocytology against 486p3/12 and LewisX. Those evaluating the tests were unaware of the clinical and histopathological data. FISH was considered positive if five or more urinary cells had gains of two or more chromosomes. The threshold for the urine tests were 10 U/mL (NMP-22), 30% positive cells (486p3/12), or 5% positive cells, respectively (LewisX).

RESULTS

The sensitivity was 69% (FISH), 67% (BTA-Stat), 69% (486p3/12), 96% (LewisX) and 71% (NMP22), respectively; the respective specificity was 89%, 78%, 76%, 33% and 66%.

CONCLUSION

Multitarget FISH had a better specificity than the other urine markers but because of its inadequate sensitivity it does not seem to be powerful enough to replace endoscopy. Optimizing the marker panel could provide a higher sensitivity.

Cyclooxygenase-2 promotes angiogenesis in pTa/T1 urothelial bladder carcinoma but does not predict recurrence

OBJECTIVE

To investigate the effect of cyclooxygenase-2 (COX-2) on microvessel density (MVD) and on the clinical prognosis in patients with non-muscle invasive urothelial carcinoma of the bladder, as COX-2 expression is significantly greater in epithelial tumours and there is increasing evidence that COX-2 might contribute to tumour neovascularization.

PATIENTS AND METHODS

We assessed tumour samples from 110 patients undergoing transurethral resection for primary pTa/pT1 bladder carcinoma (pTa, 84; pT1, 26; grade 1, 22; grade 2, 81; grade 3, seven). Paraffin sections were assessed immunohistochemically using antibodies against COX-2, CD34 (endothelial cells) and CD105 (proliferating vessels). COX-2 expression was quantified by the number of stained cells (negative, +, ++) and the MVD calculated as vessels per field.

RESULTS

Of the 110 tumours, 45 (41%) had no immunostaining for COX-2, 40 had faint staining with at least isolated positive cells (+) and 25 stained ++. COX-2 positive tumours had significantly greater vascularization for proliferating vessels. In COX-2 negative tumours the MVD was 22.1, identified by CD34 immunostaining, and 3.4 for proliferating vessels (CD105), whereas COX-2 positive tumours had a MVD of 18.3 (CD34), and of 5.8, respectively (CD105). Complete follow-up data were available in 91 patients; after a mean follow-up of 25 months, 18 (20%) had tumour recurrences. There was no significant difference in the recurrence rates or disease-free survival between COX-2-positive (19%, 25.6 months) or -negative patients (21%, 25.2 months).

CONCLUSION

These results confirm the involvement of COX-2 in angiogenesis in bladder cancer, as COX-2 promoted blood vessel proliferation in the tumour zone, and indicate the usefulness of COX-2-inhibiting drugs in preventing and treating superficial bladder cancer.

Are false-positive urine markers for the detection of bladder carcinoma really wrong or do they predict tumor recurrence?

INTRODUCTION AND OBJECTIVES

A problem in the interpretation of noninvasive urine tests for detection of bladder carcinoma is the finding of false-positive results. Several authors have described that patients with false-positive results are at high risk for tumor recurrence or progression. Only few data are available for comparing the clinical course of patients with false-positive test results and patients with true-negative results. We studied whether patients with false-positive results of various urine test had a higher recurrence rate than patients with true-negative results.

METHODS

Urine samples from 61 patients without evidence of active bladder carcinoma were included. Of the 61 patients, 51 had a history of bladder cancer, and 10 underwent transurethral resection for suspect of bladder carcinoma but had negative pathologic findings. Immunocytology (Lewis X and 486p3/12) was performed on bladder washings, and BTAstat and NMP22 were performed on urine samples.

RESULTS

During the follow-up period, 22 patients had one or more false-positive BTAstat test results, 25 patients had one or more false-positive NMP22 tests, 42 patients had at least one false-positive Lewis X test, and 11 patients had one or more false-positive 486p3/12 test. During a follow-up period of 3-39 months (median, 17.6 months) four patients expected a tumor recurrence. Among patients with false-positive urine test results 2 of 22 (9.1%, BTAstat), 2 of 25 (8%, NMP22), 4 of 42 (9.5%, Lewis X), and 3 of 11 (27.2%, 486p3/12) suffered from tumor recurrence. In contrast, among patients with true-negative test results 2 of 39 (5.2%, BTAstat), 2 of 36 (5.6%, NMP22), 0 of 18 (0%, Lewis X), 1 of 50 (2.0%, 486p3/12) had a tumor recurrence.

CONCLUSIONS

Patients with a false-positive urine test result do not generally have a greater risk of tumor recurrence or progression than patients with a true-negative result. In our series, only patients with false-positive 486p3/12 test result had a higher recurrence rate. Our findings do not justify a more aggressive adjuvant treatment or surveillance for patients with false-positive urine tests.