Human Bladder Tumor Cells Research Articles

895 Invasive human bladder tumor cells form invadopodia that is initiated by macular expression of formin-binding protein(FBP) 17

895 Invasive human bladder tumor cells form invadopodia that is initiated by macular expression of formin-binding protein(FBP) 17

Thiothymidine combined with UVA as a potential novel therapy for bladder cancer

Background:Thiothymidine (S4TdR) can be incorporated into DNA and sensitise cells to DNA damage and cell death following exposure to UVA light. Studies were performed to determine if the combination of S4TdR and UVA could be an effective treatment for bladder cancer.Methods:Uptake and incorporation of S4TdR was determined in rat and human bladder tumour cell lines. Measures of DNA crosslinking and apoptosis were also performed. In vivo activity of the combination of S4TdR and UVA was investigated in an orthotopic model of bladder cancer in rats.Results:Thiothymidine (200 μM) replaced up to 0.63% of thymidine in rat and tumour bladder cancer cells. The combination of S4TdR (10–200 μM) and UVA (1–5 kJ m−2) caused apoptosis and cell death at doses that were not toxic alone. Addition of raltitrexed (Astra Zeneca, Alderley Edge, Cheshire, UK) increased the incorporation of S4TdR into DNA (up to 20-fold at IC5) and further sensitised cells to UVA. Cytotoxic effect was associated with crosslinking of DNA, at least partially to protein. Intravenous administration of S4TdR, in combination with UVA delivered directly to the bladder, resulted in an antitumour effect in three of five animals treated.Conclusion:These data indicate that the combination of S4TdR and UVA has potential as a treatment for bladder cancer, and give some insight into the mechanism of action. Further work is necessary to optimise the delivery of the two components.

Abstract 2233: Phage display selection of cancer-specific peptides on human bladder for molecular imaging of bladder cancer

Abstract Introduction and Objectives: Molecular imaging could transform cancer diagnosis by coupling existing imaging modalities with labeled tumor-specific antibodies or peptides. Current diagnosis of bladder cancer is by white light cystoscopy, which has suboptimal specificity for differentiating non-papillary cancer from inflammation. To identify bladder cancer-specific peptides, we applied phage display, an unbiased, combinatorial strategy in which up to 10⁁9 foreign peptides or proteins are individually expressed on bacteriophage to screen against cellular targets (biopanning). We report our effort to identify bladder cancer-specific peptides via biopanning with cystectomy specimens. Methods: An M13 phage library displaying random linear heptapeptides was instilled into fresh cystectomy specimens (n=2). Non-specific phage were washed away and tumor was excised to extract tumor-bound phage, which were validated by bladder cancer cell line-based ELISA, flow cytometry, and immunofluorescence. Results: Both bladders had high-grade urothelial carcinoma on pathology. 148 phage were obtained after 2 rounds of selection. 77 of these showed preferential binding to 2 bladder cancer cell lines (HT-1376, T24) by ELISA compared to negative control (insertless phage). 7 phage with >10-fold signals over the negative control were further validated with flow cytometry and immunofluorescence. By detecting cell-bound phage with fluorescently labeled M13 phage antibody, increased staining of T24 cells by all candidate phage compared to negative control was demonstrated by both flow cytometry (2-3-fold) and immunofluorescence. Peptides were sequenced for additional validation of tumor specificity with primary normal human urothelial and bladder tumor cells. Conclusions: We have developed a technique for efficient biopanning of bladder cancer-specific peptides using whole cystectomy specimens. These peptides could serve as molecular contrast agents for targeted imaging with confocal laser endomicroscopy or fluorescent cystocsopy, and could potentially be utilized for targeted therapy. Compared to prior reports, which utilized cell lines and xenografts as biopanning targets, our approach offers a more clinically-relevant, efficient approach to identify peptides for cancer-specific imaging and therapy. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2233. doi:10.1158/1538-7445.AM2011-2233

Expression of σ receptors of human urinary bladder tumor cells (RT-4 cells) and development of a competitive receptor binding assay for the determination of ligand affinity to human σ 2 receptors

A selective competitive binding assay for the determination of the affinity of compounds to the human σ 2 receptor using 96-well multiplates and a solid state scintillator was developed. In the assay system, [ 3H]ditolylguanidine (DTG) was used as radioligand and membrane homogenates from human RT-4 cells physiologically expressing σ 2 receptors served as receptor material. In order to block the interaction of the unselective radioligand [ 3H]DTG with σ 1 receptors, all experiments were performed in the presence of the σ 1 selective ligand (+)-pentazocine. The density of σ 2 receptors of the cells was analyzed by a saturation experiment with [ 3H]DTG. The radioligand [ 3H]DTG was bound to a single, saturable site on human σ 2 receptors, resulting in a B max value of 2108 ± 162 fmol/mg protein and K d-value of 8.3 ± 2.0 nM. The expression of competing σ 1 receptors was evaluated by performing a saturation experiment using the σ 1 selective radioligand [ 3H](+)-pentazocine, which resulted in a B max value of 279 ± 40 fmol/mg protein and K d value of 13.4 ± 1.6 nM. For validation of the σ 2 binding assay, the K i-values of four σ 2 ligands (ditolylguanidine, haloperidol, rimczole and BMY-14802) were determined with RT-4 cell membrane preparations. The K i values obtained from these experiments are in good accordance with the K i-values obtained with rat liver membrane preparations as receptor material and with K i values given in the literature.

884 SELECTION OF CANCER-SPECIFIC PEPTIDES ON HUMAN BLADDER FOR MOLECULAR IMAGING OF BLADDER CANCER

INTRODUCTION AND OBJECTIVES: Molecular imaging could transform cancer diagnosis by coupling existing imaging modalities with labeled tumor-specific antibodies or peptides. Current diagnosis of bladder cancer is by white light cystoscopy, which has suboptimal specificity for differentiating non-papillary cancer from inflammation. To identify bladder cancer-specific peptides, we applied phage display, an unbiased, combinatorial strategy in which up to 10 9 foreign peptides or proteins are individually expressed on bacteriophage to screen against cellular targets (biopanning). We report our effort to identify bladder cancer-specific peptides via biopanning with cystectomy specimens. METHODS: An M13 phage library displaying random linear heptapeptides was instilled into fresh cystectomy specimens (n 2). Non-specific phage were washed away and tumor was excised to extract tumor-bound phage, which were validated by bladder cancer cell line-based ELISA, flow cytometry, and immunofluorescence. RESULTS: Both bladders had high-grade urothelial carcinoma on pathology. 148 phage were obtained after 2 rounds of selection. 77 of these showed preferential binding to 2 bladder cancer cell lines (HT-1376, T24) by ELISA compared to negative control (insertless phage). 7 phage with 10-fold signals over the negative control were further validated with flow cytometry and immunofluorescence. By detecting cell-bound phage with fluorescently labeled M13 phage antibody, increased staining of T24 cells by all candidate phage compared to negative control was demonstrated by both flow cytometry (2–3-fold) and immunofluorescence. Peptides were sequenced for additional validation of tumor specificity with primary normal human urothelial and bladder tumor cells. CONCLUSIONS: We have developed a technique for efficient biopanning of bladder cancer-specific peptides using whole cystectomy specimens. These peptides could serve as molecular contrast agents for targeted imaging with confocal laser endomicroscopy or fluorescent cystocsopy, and could potentially be utilized for targeted therapy. Compared to prior reports, which utilized cell lines and xenografts as biopanning targets, our approach offers a more clinically-relevant, efficient approach to identify peptides for cancer-specific imaging and therapy. Source of Funding: Stanford University Cancer Center Developmental Cancer Research Award Stanford University School of Medicine Dean’s Postdoctoral Fellowship

Sensitization of human bladder tumor cells to TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis with a small molecule IAP antagonist

Urothelial carcinoma of the bladder accounts for approximately 5% of all cancer deaths in humans. The large majority of bladder tumors are non-muscle invasive at diagnosis, but even after local surgical therapy there is a high rate of local tumor recurrence and progression. Current treatments extend time to recurrence but do not significantly alter disease survival. The objective of the present study was to investigate the tumoricidal potential of combining the apoptosis-inducing protein TNF-related apoptosis-inducing ligand (TRAIL) with a small molecule inhibitor of apoptosis proteins (IAP) antagonist to interfere with intracellular regulators of apoptosis in human bladder tumor cells. Our results demonstrate that the IAP antagonist Compound A exhibits high binding affinity to the XIAP BIR3 domain. When Compound A was used at nontoxic concentrations in combination with TRAIL, there was a significant increase in the sensitivity of TRAIL-sensitive and TRAIL-resistant bladder tumor lines to TRAIL-mediated apoptosis. In addition, modulation of TRAIL sensitivity in the TRAIL-resistant bladder tumor cell line T24 with Compound A was reciprocated by XIAP small interfering RNA-mediated suppression of XIAP expression, suggesting the importance of XIAP-mediated resistance to TRAIL in these cells. These results suggest the potential of combining Compound A with TRAIL as an alternative therapy for bladder cancer.

Mouse models of human bladder cancer as a tool for drug discovery.

Muscle-invasive bladder cancer is a deadly condition in dire need of effective new treatments. This unit contains a description of mouse models suitable for the evaluation of potential new therapies. Included is a genetically engineered mouse model of bladder cancer generated by the delivery of an adenovirus expressing Cre recombinase into the bladder lumen. Also described is an orthotopic mouse model created by the instillation of human bladder tumor cells into the bladder lumen of immune deficient mice. Protocols are also provided on the use of these models for the preclinical evaluation of new chemical entities, with mTOR inhibitors shown as an example.

Invadopodia Formation by Bladder Tumor Cells

A major cause of death in patients with bladder tumors is recurrence with metastasis. Bladder tumor metastasis is largely dependent upon the invasive capacity of tumor cells. Tumor cell invasion is mainly mediated by actin-rich protrusive membrane structures called invadopodia. The formation of invadopodia was observed in various types of invasive tumors such as breast cancer and melanomas. However, invadopodia formation so far has not been described in bladder tumor cells. We here report that human bladder tumor cells form functionally active invadopodia. By using a confocal laser scanning microscope, we demonstrated that invasive bladder tumor cell lines, YTS-1 and T24, with high Matrigel degradation activity form invadopodia but that noninvasive bladder tumor cell lines, RT4 and KK-47, form no detectable invadopodia. Invadopodia formed by YTS-1 cells had the ability to secrete matrix metalloproteases and degrade extracellular matrix to invade surrounding areas. Moreover, we observed that primary tumor cells obtained from patients with invasive bladder tumors also form invadopodia, validating the results from bladder tumor cell lines. Our results provide evidence that invasive human bladder tumor cells form invadopodia for tumor invasion.

Triterpenoid Saponins from Ardisia gigantifolia

Four new triterpenoid saponins (1-4) were isolated from the rhizome of Ardisia gigantifolia STAPF. The structures of new saponins were established as 3beta-o-alpha-L-rhamnopyranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-glucopyranosyl-(1-->4)-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl-16alpha-hydroxy-13,28-epoxy-oleanane (1), 3beta-o-alpha-L-rhamnopyranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-glucopyranosyl-(1-->4)-[beta-D-glucopyrano-syl-(1-->2)]-alpha-L-arabinopyranosyl-16alpha-hydroxy-13,28-epoxy-30-acetoxy-oleanane (2), 3beta-o-alpha-L-rhamnopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->2)]-beta-D-glucopyranosyl-(1-->4)-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl-16alpha-hydroxy-13,28-epoxy-oleanane (3) and 3beta-o-alpha-L-rhamnopyranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-glucopyranosyl-(1-->4)-[beta-D-6-O-acetylglucopranosyl-(1-->2)]-alpha-L-arabinopyranosyl-16alpha-hydroxy-13,28-epoxy-oleanane (4) were isolated from Ardisia gigantifolia STAPF. Their structures were elucidated by means of (1)H- and (13)C-NMR spectroscopic studies, including 2D-NMR technique. The cytotoxic activities of saponins 1-4 are reported against three human cancer cell lines, namely, Hela human cervical carcinoma cells, EJ human bladder tumor cells, and BCG-823 human gastric carcinoma cells.

Dendritic Cell Transfected with Secondary Lymphoid-Tissue Chemokine and/or Interleukin-2 Gene-Enhanced Cytotoxicity of T-Lymphocyte in Human Bladder Tumor Cell S In Vitro

ABSTRACTObjectives: The aim of this study was to investigate whether dendritic cells (DCs) transfected with human secondary lymphoid-tissue chemokine (hSLC) and human interleukin-2 (hIL-2) genes are capable of improving DC's proliferation and to produce a marked antitumor effect in vitro combined with T-lymphocyte (TC). Methods: SLC gene primer was designed based on the corresponding gene sequence in GenBank. The Kpn I site was introduced into the upstream of the primer and Xho I site into the downstream. The SLC gene was amplified with the template of pET32a(+)-SLC by polymerase chain reaction. SLC was cloned into pBudCE4.1/IL-2 (TRAIL was cut from pBudCE4.1/TRAIL- IL-2 before) to construct recombinant plasmid pBudCE4.1/SLC-IL-2(PSI). DCs were transfected with pBudCE4.1/SLC-IL-2 by gene electric transfection. Protein expression was determined with Western blot and enzyme-linked immunosorbent assays. Cytotoxicity of TC and DC against the human bladder tumor cell were examined by chromium release assay. Flow cytometric analyses were performed to determine the apoptosis of tumor cells and the percentage of Treg. Results: A high level of expression of SLC and IL-2 was observed in DCs transfected with SLC and IL-2 genes. The mean production of IL-2 was 19.8 ± 2.5, 511.10 ± 52.36, and 541.3 ± 62.04 ng/106 cells/24 hours in the DC/vector, DC/IL-2, and DC/SLC-IL-2, respectively. The mean SLC production was 29.8 ± 4.43, 506.10 ± 42.36, and 567.34 ± 52.05 ngs/106cells/24 hours in the DC/ vector, DC/SLC, and DC/SLC-IL-2, respectively. Cytotoxicity to bladder cancer cells was increased. The mean cytotoxicity (the effector/target ratio, 40:1) of TC-DC/parental, TC-DC/IL-2, TC-DC/SLC, and TC-DC/SLC-IL-2(TDSI) to the human bladder cancer cells was 32.1 ± 5.5%, 63.5 ± 6.6%, 78.1 ± 9.63%, respectively. The apoptotsis rate of bladder cancer cells treated with TDSI was 18.6% by flow cytometry. Treg cells' percentage was very small in the DC medium. Conclusions: SLC and IL-2 were produced by autocrine in DCs transfected with SLC and IL-2 genes. DC/SLC-IL-2 can promote DC proliferation, while TC-DC/SLC-IL-2 and TC-DC/SLC could strongly enhance significant cytotoxicity against bladder cancer cell that was induced by the coculture of DCs (transfected with SLC and IL-2) and TC.

A critical role for choline kinase-α in the aggressiveness of bladder carcinomas

Bladder cancer is one of the most common causes of death in industrialized countries. New tumor markers and therapeutic approaches are still needed to improve the management of bladder cancer patients. Choline kinase-alpha (ChoKalpha) is a metabolic enzyme that has a role in cell proliferation and transformation. Inhibitors of ChoKalpha show antitumoral activity and are expected to be introduced soon in clinical trials. This study aims to assess whether ChoKalpha plays a role in the aggressiveness of bladder tumors and constitutes a new approach for bladder cancer treatment. We show here that ChoKalpha is constitutively altered in human bladder tumor cells. Furthermore, in vivo murine models, including an orthotopic model to mimic as much as possible the physiological conditions, revealed that increased levels of ChoKalpha potentiate both tumor formation (P< or =0.0001) and aggressiveness of the disease on different end points (P=0.011). Accordingly, increased levels of ChoKalpha significantly reduce survival of mice with bladder cancer (P=0.05). Finally, treatment with a ChoKalpha-specific inhibitor resulted in a significant inhibition of tumor growth (P=0.02) and in a relevant increase in survival (P=0.03).

A possible mechanism of intravesical BCG therapy for human bladder carcinoma: involvement of innate effector cells for the inhibition of tumor growth.

Intravesical bacillus Calmette-Guerin (BCG) therapy is considered the most successful immunotherapy against solid tumors of human bladder carcinoma. To determine the actual effector cells activated by intravesical BCG therapy to inhibit the growth of bladder carcinoma, T24 human bladder tumor cells, expressing very low levels of class I MHC, were co-cultured with allogeneic peripheral blood mononuclear cells (PBMCs) with live BCG. The proliferation of T24 cells was markedly inhibited when BCG-infected dendritic cells (DCs) were added to the culture although the addition of either BCG or uninfected DCs alone did not result in any inhibition. The inhibitory effect was much stronger when the DCs were infected with live BCG rather than with heat-inactivated BCG. The live BCG-infected DCs secreted TNF-alpha and IL-12 within a day and this secretion continued for at least a week, while the heat-inactivated BCG-infected DCs secreted no IL-12 and little TNF-alpha. Such secretion of cytokines may activate innate alert cells, and indeed NKT cells expressing IL-12 receptors apparently proliferated and were activated to produce cytocidal perforin among the PBMCs when live BCG-infected DCs were externally added. Moreover, depletion of gammadelta T-cells from PBMCs significantly reduced the cytotoxic effect on T24 cells, while depletion of CD8beta cells did not affect T24 cell growth. Furthermore, the innate effectors seem to recognize MICA/MICB molecules on T24 via NKG2D receptors. These findings suggest the involvement of innate alert cells activated by the live BCG-infected DCs to inhibit the growth of bladder carcinoma and provide a possible mechanism of intravesical BCG therapy.

Dendritic Cell Transfected with Secondary Lymphoid-Tissue Chemokine and/or Interleukin-2 Gene-Enhanced Cytotoxicity of T-Lymphocyte in Human Bladder Tumor Cell S In Vitro

Dendritic Cell Transfected with Secondary Lymphoid-Tissue Chemokine and/or Interleukin-2 Gene-Enhanced Cytotoxicity of T-Lymphocyte in Human Bladder Tumor Cell S In Vitro

Cytotoxic T-lymphocytes response in vitro activated by dendritic cells pulsed with heat shock protein 70 derived from human bladder tumor cell lines of EJ

Objective To investigate whether human dendritic cells (DC) derived from peripheral blood mononuclear cells (PBMC), which were pulsed by heat shock protein 70 (HSP70) isolated from human bladder tumor cell lines of EJ, were able to induce peptide specific cytotoxic T-lymphocytes (CTL) response in vitro and give the experimental foundation for the future clinical trials of immunotherapy in bladder tumor.

Establishment of multidrug resistance cell line of human bladder tumor T24/ADM and the expression analysis of mechanism of multidrug resistance

Objective To establish a multidrug resistance cell line of human bladder tumor and study its characteristics and mechanism of muhidrug resistance. Methods Human bladder tumor cell line T24 was induced to muhidrug resistance cell line T24/ADM by intermittent administration of high dose ADM. The multidrug resistance to multianticancer agents of the ceils was evaluated by MTT assay; the expression of MDR gene was assessed by RT-PCR and P-gp expression was determined by flow cytometry. Results T24/ ADM resisted to many anti-tumor agents, and its IC50 of ADM was 16.3 times higher than that of T24. Significant overexpression of MDR gene and p-gp of the multidrug resistant cells were detected. Conclusion T24/ADM is a human muhidrug-resistant cell line, and it's drug resistance relates to the overexpression of MDR gene and p-gp. Key words: Urinary bladder neoplasms; Cell line, tumor, Muhidrug resistance-associated protein; Genes MDR

Intravesical Chemotherapy of High-Grade Bladder Cancer with HTI-286, A Synthetic Analogue of the Marine Sponge Product Hemiasterlin

HTI-286 is a fully synthetic analogue of the natural tripeptide hemiasterlin that inhibits tubulin polymerization and has strong cytotoxic potential. In this study, we evaluate the inhibitory effects of HTI-286 on human bladder cancer growth, both in vitro and as an intravesical agent in an orthotopic murine model. Various bladder cancer cell lines were treated with HTI-286 and mitomycin C (MMC) in vitro. Human KU-7 bladder tumor cells that stably express firefly luciferase were inoculated in female nude mice by intravesical instillation and quantified using bioluminescence imaging. Mice with established KU-7-luc tumors were given HTI-286 or MMC intravesically twice a week for 2 h. Pharmacokinetic data was obtained using high-performance liquid chromatography-mass spectrometry analyses. In vitro, HTI-286 was a potent inhibitor of proliferation in all tested cell lines and induced marked increases in apoptosis of KU-7-luc cells even after brief exposure. In vivo, HTI-286 significantly delayed cancer growth of bladder tumors in a dose-dependent fashion. HTI-286, at a concentration of 0.2 mg/mL, had comparable strong cytotoxicity as 2.0 mg/mL of MMC. The estimated systemic bioavailability of intravesically given HTI-286 was 1.5% to 2.1% of the initial dose. Intravesical HTI-286 instillation therapy showed promising antitumor activity and minimal toxicity in an orthotopic mouse model of high-grade bladder cancer. These findings provide preclinical proof-of-principle for HTI-286 as an intravesical therapy for nonmuscle-invasive bladder cancer and warrant further evaluation of efficacy and safety in early-phase clinical trials.

Oral Silibinin Inhibits In vivo Human Bladder Tumor Xenograft Growth Involving Down-Regulation of Survivin

Chemoprevention is an upcoming approach to control bladder cancer, which is one of the commonly diagnosed malignancies showing recurrence rate of 70% or even higher. Recently, we observed the in vitro efficacy of silibinin, a flavanolignan, in human bladder transitional cell papilloma RT4 cells. Here, we investigated the antitumor efficacy and associated mechanisms of silibinin in RT4 tumor xenograft. RT4 tumor xenograft was implanted s.c. in athymic nude mice, and then animals were oral gavaged with silibinin at 100 and 200 mg/kg doses, 5 days/week for 12 weeks. Tumor growth, body weight, and diet consumption were recorded, and tumors were analyzed for proliferation, apoptosis, and angiogenesis biomarkers and molecular alterations by immunohistochemistry, immunoblot analysis, and ELISA. p53 small interfering RNA was used in cell culture to examine the role of p53 in survivin expression. Silibinin feeding inhibited tumor xenograft growth without any gross signs of toxicity. Silibinin decreased tumor volume by 51% to 58% (P <or= 0.01) and tumor weight by 44% to 49% (P < 0.05). Silibinin moderately (P < 0.001) decreased cell proliferation and microvessel density and strongly (P < 0.001) increased apoptosis in tumors. Silibinin robustly decreased survivin protein expression and its nuclear localization, as well as tumor-secreted level in mouse plasma, but increased p53 and cleaved caspase-3 levels in tumors. Silibinin-caused decrease in survivin was independent of p53. These findings identified in vivo antitumor efficacy of silibinin against human bladder tumor cells involving down-regulation of survivin and an increase in p53 expression together with enhanced apoptosis.

Association of vitamin‐D receptor (Fok‐I) gene polymorphism with bladder cancer in an Indian population

To explore the association of vitamin-D receptor (VDR) genotypes and haplotypes (variants at the Fok-I, and Taq-I sites) with the risk of bladder cancer, as vitamin D is antiproliferative and reported to induce apoptosis in human bladder tumour cells in vitro. A case-control study using polymerase chain reaction-restriction fragment length polymorphism was conducted in 130 patients with bladder cancer and 346 normal healthy individuals in a north Indian population. Patients were also categorized according to grade and stage of tumour. There was a significant difference in genotype and allelic distribution of VDR (Fok-I) polymorphism in the patients (P = 0.033 and = 0.017, respectively). The FF genotype was associated with twice the risk for bladder cancer (odds ratio 2.042, 95% confidence interval, CI, 0.803-5.193). There was no significant difference in genotypic distribution or allelic frequencies of the VDR (Taq-I) polymorphism (P = 0.477 and 0.230) when compared with the controls. The stage and grade of the bladder tumours had no association with VDR (Fok-I and Taq-I) genotypes. There was a significant difference in the frequency distribution of the haplotypes FT and fT (P < 0.001); these haplotypes had a protective effect in the control group (odds ratio 0.167, 95% CI 0.096-0.291, and 0.079, 0.038-0.164). These data suggest that VDR (Fok-I) polymorphism is associated with the risk of bladder cancer. Further, the results for the haplotype FT and fT indicate that patients with this haplotype have a lower risk of developing bladder cancer than those with other haplotypes.

MP-600 Establishment and Characterization of a Novel Human bladder tumor cell line : Analysis of CD95 mediated apoptosis and survivin expression

MP-600 Establishment and Characterization of a Novel Human bladder tumor cell line : Analysis of CD95 mediated apoptosis and survivin expression

Increased expression of the acid sphingomyelinase-like protein ASML3a in bladder tumors.

The function of the tumor suppressor gene DBCCR1 (deleted in bladder cancer chromosome region 1) is unknown despite data supporting an important role for DBCCR1 in bladder tumorigenesis. DBCCR1 has not yet been placed in a protein family or functional pathway. Protein-protein interactions are crucial for almost every aspect of cellular function. We hypothesized that the discovery of DBCCR1 protein binding partners would yield important clues for solving the mystery of DBCCR1 function. We used the yeast 2-hybrid system to screen an adult human bladder cDNA library for DBCCR1 interacting proteins. In the screen ASML3a (acid sphingomyelinase-like phosphodiesterase 3a) was identified as a novel DBCCR1 binding partner. Transient transfection of bladder tumor cell lines showed that DBCCR1 over expression in human bladder tumor cells results in the up-regulation of ASML3a RNA and protein expression. ASML3a protein was also differentially expressed in 8 of 12 bladder tumors relative to corresponding normal urothelial tissue. It appears that DBCCR1 and ASML3a are involved in the process of bladder tumorigenesis. Their interaction may provide clues to discern their functions.