Orthotopic Bladder Tumor Model Research Articles

Bacterial outer membrane vesicle nanorobot

Autonomous nanorobots represent an advanced tool for precision therapy to improve therapeutic efficacy. However, current nanorobotic designs primarily rely on inorganic materials with compromised biocompatibility and limited biological functions. Here, we introduce enzyme-powered bacterial outer membrane vesicle (OMV) nanorobots. The immobilized urease on the OMV membrane catalyzes the decomposition of bioavailable urea, generating effective propulsion for nanorobots. This OMV nanorobot preserves the unique features of OMVs, including intrinsic biocompatibility, immunogenicity, versatile surface bioengineering for desired biofunctionalities, capability of cargo loading and protection. We present OMV-based nanorobots designed for effective tumor therapy by leveraging the membrane properties of OMVs. These involve surface bioengineering of robotic body with cell-penetrating peptide for tumor targeting and penetration, which is further enhanced by active propulsion of nanorobots. Additionally, OMV nanorobots can effectively safeguard the loaded gene silencing tool, small interfering RNA (siRNA), from enzymatic degradation. Through systematic in vitro and in vivo studies using a rodent model, we demonstrate that these OMV nanorobots substantially enhanced siRNA delivery and immune stimulation, resulting in the utmost effectiveness in tumor suppression when juxtaposed with static groups, particularly evident in the orthotopic bladder tumor model. This OMV nanorobot opens an inspiring avenue to design advanced medical robots with expanded versatility and adaptability, broadening their operation scope in practical biomedical domains.

Abstract 2816: Comparison of MB-49_luc bladder carcinoma cell clones in the orthotopic superficial bladder tumor model in C57BL/6 female mice

Abstract In preclinical research, cell inoculation via bladder wall injection is a standard for studying invasive bladder cancer into the bladder muscle wall. However, a subset of patients presents with non-muscle invasive (superficial) disease. The standard of care for these patients is excision coupled with BCG treatment via catheterization. There is a need to further establish mouse models of cell inoculation via bladder catheterization for early drug development. While the injection places cells into the bladder wall, catheterization coats the inside of the bladder by first instilling Poly-L-Lysine. After instilling Poly-L-Lysine, instillation of luciferase-tagged cell suspension occurs. MB49-luc cell lines were generated to determine the optimal cell lines for use in analyzing treatments for superficial bladder carcinoma. MB49-luc cells display varying degrees of luciferase activity and growth in vitro. A subset of cell lines were selected for further analysis in vivo, via bioluminescent imaging, survival analysis, flow cytometry and necropsy. The data provides a preclinical reference for the selection of a cell line for analysis of new drug candidates in C57BL/6 female mice inoculated via bladder catheterization. Citation Format: Mollie McArthur, Melissa Tran, Aliccia Koznecki, Helen Ketteringham, Corrine Silvio, Shannan Wenzel, Cheryl Davis, Shorena Nadaraia-Hoke, Chris Holding, Logan Salem, Victoria Caruso, Ben Hoerner, Madison Spencer, Marcus Josey, Alexa Tannu. Comparison of MB-49_luc bladder carcinoma cell clones in the orthotopic superficial bladder tumor model in C57BL/6 female mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2816.

Type 2 innate lymphoid cells are not involved in mouse bladder tumor development.

Therapies for bladder cancer patients are limited by side effects and failures, highlighting the need for novel targets to improve disease management. Given the emerging evidence highlighting the key role of innate lymphoid cell subsets, especially type 2 innate lymphoid cells (ILC2s), in shaping the tumor microenvironment and immune responses, we investigated the contribution of ILC2s in bladder tumor development. Using the orthotopic murine MB49 bladder tumor model, we found a strong enrichment of ILC2s in the bladder under steady-state conditions, comparable to that in the lung. However, as tumors grew, we observed an increase in ILC1s but no changes in ILC2s. Targeting ILC2s by blocking IL-4/IL-13 signaling pathways, IL-5, or IL-33 receptor, or using IL-33-deficient or ILC2-deficient mice, did not affect mice survival following bladder tumor implantation. Overall, these results suggest that ILC2s do not contribute significantly to bladder tumor development, yet further investigations are required to confirm these results in bladder cancer patients.

Establishment of Mouse Orthotopic Urinary Bladder Tumor Model and Its Analysis by Light and Electron Microscopy.

Mouse tumor models are an important tool in cancer research, and the orthotopic cancer cell transplantation model is the most widely used among them. Methods for establishing tumor models may differ in many ways, including the selection of cancer cell lines and the type of urinary bladder pretreatment. Here, we describe our mouse orthotopic bladder tumor model using a labeled MB49 urothelial cancer cell line and chemical pretreatment with the cationic polypeptide poly-L-lysine to traumatize the bladder epithelium. Double labeling of MB49 cancer cells by their transduction with GFP and internalization of metal nanoparticles allows the study of their implantation process from the first hours to several days after intravesical injection, as well as the analysis of developed tumors after 3weeks. Thus, our model provides a comprehensive analysis of the early and late stages of tumor development in the bladder at the light and electron microscopic level.

Co-delivery of oxaliplatin prodrug liposomes with Bacillus Calmette-Guérin for chemo-immunotherapy of orthotopic bladder cancer

To reduce recurrence rate after transurethral resection of bladder tumor, long-term intravesical instillations of Bacillus Calmette-Guérin (BCG) and/or chemotherapeutic drugs is the standard treatment for non-muscle invasive bladder carcinoma. However, the main challenges of intravesical therapy, such as short retention time and poor permeability of drugs in the bladder, often require frequent and high-dose administrations, leading to significant adverse effects and financial burden for patients. Aiming at addressing these challenges, we developed a novel approach, in which the cell-penetrating peptide modified oxaliplatin prodrug liposomes and a low-dose BCG were co-delivered via a viscous chitosan solution (LRO-BCG/CS). LRO-BCG/CS addressed these challenges by significantly improving the retention capability and permeability of chemotherapy agents across the bladder wall. Then, oxaliplatin triggered the immunogenic cell death, and the combination of BCG simultaneously further activated the systemic anti-tumor immune response in the MB49 orthotopic bladder tumor model. As a result, LRO-BCG/CS demonstrated superior anti-tumor efficacy and prolonged the survival time of tumor-bearing mice significantly, even at relatively low doses of oxaliplatin and BCG. Importantly, this combinational chemo-immunotherapy showed negligible side effects, offering a promising and well-tolerated therapeutic strategy for bladder cancer patients.

RGD peptide modified platinum nanozyme Co-loaded glutathione-responsive prodrug nanoparticles for enhanced chemo-photodynamic bladder cancer therapy

Bladder cancer is one of the most common malignant tumors in the urinary system worldwide. The poor permeability and uncontrollable release of drug and hypoxia of tumor tissues were the main reasons leading to poor therapeutic effect of chemo-photodynamic therapy for bladder cancer. To solve the above problems, a tumor-targeting peptide Arg-Gly-Asp (RGD) modified platinum nanozyme (PtNP) co-loaded glutathione (GSH)-responsive prodrug nanoparticles (PTX–SS–HPPH/Pt@RGD-NP) was constructed. Firstly, a GSH-responsive prodrug (PTX–SS–HPPH) was prepared by introducing a disulfide bond between paclitaxel (PTX) and photosensitizer 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH), which could realize the GSH-responsive release of the drug at the tumor sites. Also, the distearoylphosphoethanolamine-poly (ethylene glycol)-RGD peptide (DSPE-PEG-RGD) modified the prodrug to enhance the targeting and permeability ability to bladder cancer cells. Besides, to alleviate the hypoxia of tumor tissues, PtNP was introduced to produce oxygen (O2) and improve photodynamic therapy efficiency. The results showed that the PTX–SS–HPPH/Pt@RGD-NP could achieve GSH-responsive drug release in tumor microenvironment, enhance the drug accumulation time and permeability at tumor sites in T24 subcutaneous tumor model and T24 orthotopic bladder tumor model, and alleviate hypoxia in tumor tissues, thus realizing enhanced chemo-photodynamic therapy for bladder cancer, and providing new strategies and methods for clinical treatment of bladder cancer.

Magnetic-Powered Janus Cell Robots Loaded with Oncolytic Adenovirus for Active and Targeted Virotherapy of Bladder Cancer.

A unique robotic medical platform is designed by utilizing cell robots as the active "Trojan horse" of oncolytic adenovirus (OA), capable of tumor-selective binding and killing. The OA-loaded cell robots are fabricated by entirely modifying OA-infected 293T cells with cyclic arginine-glycine-aspartic acid tripeptide (cRGD) to specifically bind with bladder cancer cells, followed by asymmetric immobilization of Fe3 O4 nanoparticles (NPs) on the cell surface. OA can replicate in host cells and induce cytolysis to release the virus progeny to the surrounding tumor sites for sustainable infection and oncolysis. The asymmetric coating of magnetic NPs bestows the cell robots with effective movement in various media and wireless manipulation with directional migration in a microfluidic device and bladder mold under magnetic control, further enabling steerable movement and prolonged retention of cell robots in the mouse bladder. The biorecognition of cRGD and robust, controllable propulsion of cell robots work synergistically to greatly enhance their tissue penetration and anticancer efficacy in the 3D cancer spheroid and orthotopic mouse bladder tumor model. Overall, this study integrates cell-based microrobots with virotherapy to generate an attractive robotic system with tumor specificity, expanding the operation scope of cell robots in biomedical community.

How Cancer Cells Invade Bladder Epithelium and Form Tumors: The Mouse Bladder Tumor Model as a Model of Tumor Recurrence in Patients.

Non-muscle-invasive bladder cancer is the most common form of bladder cancer. The main problem in managing bladder tumors is the high recurrence after the transurethral resection of bladder tumors (TURBT). Our study aimed to examine the fate of intravesically applied cancer cells as the implantation of cancer cells after TURBT is thought to be a cause of tumor recurrence. We established an orthotopic mouse bladder tumor model with MB49-GFP cancer cells and traced them during the first three days to define their location and contacts with normal urothelial cells. Data were obtained by Western blot, immunolabeling, and light and electron microscopy. We showed that within the first two hours, applied cancer cells adhered to the traumatized epithelium by cell projections containing α3β1 integrin on their tips. Cancer cells then migrated through the epithelium and on day 3, they reached the basal lamina or even penetrated it. In established bladder tumors, E-cadherin and desmoplakin 1/2 were shown as feasible immunohistochemical markers of tumor margins based on the immunolabeling of various junctional proteins. Altogether, these results for the first time illustrate cancer cell implantation in vivo mimicking cellular events of tumor recurrence in bladder cancer patients.

How cancer cells attach to urinary bladder epithelium in vivo: study of the early stages of tumorigenesis in an orthotopic mouse bladder tumor model.

The majority of bladder cancers in humans are non-muscle-invasive cancers that recur frequently after standard treatment procedures. Mouse models are widely used to develop anti-tumor treatments. The purpose of our work was to establish an orthotopic mouse bladder tumor model and to explore early stages of implantation of cancerous MB49 cells in vivo using various labeling and microscopic techniques. To distinguish cancer cells from normal urothelial cells in mouse urinary bladders, we performed molecular characterization of MB49 cells before intravesical injection experiments. In this new approach we applied internalized metal nanoparticles to unequivocally discriminate cancer cells from normal cells. This method revealed that cancer cells attached to the urothelium or basal lamina within just 1hour of intravesical injection, whereas small tumors and localized hyperplastic urothelial regions developed within two days. We found that cancer cells initially adhere to normal urothelial cells through filopodia and by focal contacts with basal lamina. This is the first in vivo characterization of intercellular contacts between cancerous and normal urothelial cells in the bladder. Our study yields new data about poorly known early events of tumorigenesis in vivo, which could be helpful for the translation into clinic.

MP44-01 IN VIVO FLUORESCENCE IMAGING OF AN ORTHOTOPIC RAT BLADDER TUMOR MODEL INDICATES DIFFERENTIAL UPTAKE OF INTRAVESICALLY INSTILLED NEAR-INFRARED LABELED 2-DEOXYGLUCOSE ANALOG BY NEOPLASTIC URINARY BLADDER TISSUES

You have accessJournal of UrologyBladder Cancer: Basic Research & Pathophysiology I1 Apr 2017MP44-01 IN VIVO FLUORESCENCE IMAGING OF AN ORTHOTOPIC RAT BLADDER TUMOR MODEL INDICATES DIFFERENTIAL UPTAKE OF INTRAVESICALLY INSTILLED NEAR-INFRARED LABELED 2-DEOXYGLUCOSE ANALOG BY NEOPLASTIC URINARY BLADDER TISSUES Joel Slaton, Carole Davis, Robert Hurst, and Daqing Piao Joel SlatonJoel Slaton More articles by this author , Carole DavisCarole Davis More articles by this author , Robert HurstRobert Hurst More articles by this author , and Daqing PiaoDaqing Piao More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1332AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Bladder cancer is one of the most expensive cancers to manage due to frequent recurrences requiring life-long surveillance and treatment. Deoxyglucose radionucleotides have been shown to detect metastatic bladder cancer. This pilot study has explored differential uptake of intravesically administered IRDye800CW-DG, a near-infrared labeled 2-deoxy-d-glucose probe targeting glucose metabolism pathway, to detect surface cancer in an orthotopic rodent bladder tumor model. METHODS Twenty-five female Fischer rats were randomly grouped to four conditions: control (n=3), control and intravesically instilled with IRDye800CW-DG (n=6), treated with GFP-labeled AY-27 rat bladder urothelial cell carcinoma cells and washed with saline (n=5), and treated with AY-27 and intravesically instilled with IRDye800CW-DG (n=11). Near-infrared fluorescence was measured from the opened bladder wall of anesthetized rat at an excitation wavelength of 750nm and an emission wavelength of 776nm, by using an in-house fluorescence imaging system. RESULTS There is no statistically significant difference of the peak fluorescence intensity among the control bladders (n=3), the control bladders instilled with IRDye800CW-DG (n=6), and the GFP-labeled AY-27 treated bladders washed by saline (n=5). When compared to that of the control bladders instilled with IRDye800CW-DG (n=6), the fluorescence intensity of GFP-labeled AY-27 treated bladders instilled with IRDye800CW-DG and with histology confirmed neoplastic bladder tissue (n=11) was remarkably stronger (3.34 folds of the former) that was also statistically significant (p<0.0001). CONCLUSIONS The differential uptake of IRDye800CW-DG by the neoplastic urinary bladder tissues suggests the potential for cystoscopy-adaptation to enhance diagnosis and guiding surgical management of flat urinary bladder cancer. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e563 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Joel Slaton More articles by this author Carole Davis More articles by this author Robert Hurst More articles by this author Daqing Piao More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

A Murine Orthotopic Bladder Tumor Model and Tumor Detection System.

This protocol describes the generation of bladder tumors in female C57BL/6J mice using the murine bladder cancer cell line MB49, which has been modified to secrete human Prostate Specific Antigen (PSA), and the procedure for the confirmation of tumor implantation. In brief, mice are anesthetized using injectable drugs and are made to lay in the dorsal position. Urine is vacated from the bladder and 50 µL of poly-L-lysine (PLL) is slowly instilled at a rate of 10 µL/20 s using a 24 G IV catheter. It is left in the bladder for 20 min by stoppering the catheter. The catheter is removed and PLL is vacated by gentle pressure on the bladder. This is followed by instillation of the murine bladder cancer cell line (1 x 105 cells/50 µL) at a rate of 10 µL/20 s. The catheter is stoppered to prevent premature evacuation. After 1 h, the mice are revived with a reversal drug, and the bladder is vacated. The slow instillation rate is important, as it reduces vesico-ureteral reflux, which can cause tumors to occur in the upper urinary tract and in the kidneys. The cell line should be well re-suspended to reduce clumping of cells, as this can lead to uneven tumor sizes after implantation. This technique induces tumors with high efficiency. Tumor growth is monitored by urinary PSA secretion. PSA marker monitoring is more reliable than ultrasound or fluorescence imaging for the detection of the presence of tumors in the bladder. Tumors in mice generally reach a maximum size that negatively impacts health by about 3 - 4 weeks if left untreated. By monitoring tumor growth, it is possible to differentiate mice that were cured from those that were not successfully implanted with tumors. With only end-point analysis, the latter may be mistakenly assumed to have been cured by therapy.

A Murine Orthotopic Bladder Tumor Model and Tumor Detection System

This protocol describes the generation of bladder tumors in female C57BL/6J mice using the murine bladder cancer cell line MB49, which has been modified to secrete human Prostate Specific Antigen (PSA), and the procedure for the confirmation of tumor implantation. In brief, mice are anesthetized using injectable drugs and are made to lay in the dorsal position. Urine is vacated from the bladder and 50 µL of poly-L-lysine (PLL) is slowly instilled at a rate of 10 µL/20 s using a 24 G IV catheter. It is left in the bladder for 20 min by stoppering the catheter. The catheter is removed and PLL is vacated by gentle pressure on the bladder. This is followed by instillation of the murine bladder cancer cell line (1 x 105 cells/50 µL) at a rate of 10 µL/20 s. The catheter is stoppered to prevent premature evacuation. After 1 h, the mice are revived with a reversal drug, and the bladder is vacated. The slow instillation rate is important, as it reduces vesico-ureteral reflux, which can cause tumors to occur in the upper urinary tract and in the kidneys. The cell line should be well re-suspended to reduce clumping of cells, as this can lead to uneven tumor sizes after implantation. This technique induces tumors with high efficiency. Tumor growth is monitored by urinary PSA secretion. PSA marker monitoring is more reliable than ultrasound or fluorescence imaging for the detection of the presence of tumors in the bladder. Tumors in mice generally reach a maximum size that negatively impacts health by about 3 - 4 weeks if left untreated. By monitoring tumor growth, it is possible to differentiate mice that were cured from those that were not successfully implanted with tumors. With only end-point analysis, the latter may be mistakenly assumed to have been cured by therapy.

Comparison of therapeutic efficacy of lipo-doxorubicin and doxorubicin in treating bladder cancer

ObjectivesDoxorubicin is commonly used in the treatment of superficial bladder cancer, but more side effects and shorter intracellular retention time hamper its clinical application. Since lipo-doxorubicin (Lipodox) has the advantages of longer half-life and lower clearance rate than doxorubicin, it should improve the efficacy of tumor therapy and reduce the normal tissue toxicity of doxorubicin. Materials and MethodsIn this study, we compared the cytotoxicity of Lipodox and doxorubicin in different treatment durations on bladder cancer cells by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Drug distribution was tracked under fluorescence microscopy. The metabolic rate after treatment was measured by serial flow cytometry. Finally, an in vivo orthotopic MBT-2 bladder tumor model was established for comparing the differences of therapeutic efficacy, including tumor weight and survival rate. ResultsThe 50% inhibitory concentration (IC50) of doxorubicin and Lipodox for MBT-2 cells was 0.62 μg/mL and 130 μg/mL, respectively, after 48 hours treatment. Lipo-dox presented higher cytotoxicity than doxorubicin at 6 hours (93% vs 73%) and 12 hours (93% vs 80%) treatment. After drug treatment, Lipodox fluorescence distribution was observed mostly in the cell membrane, lysosomes, and nuclei of tumor cells, while doxorubicin was concentrated in the nuclei. Initial fluorescence intensity of doxorubicin was 27.3 times that of Lipodox (p < 0.001) at time of treatment. The fluorescence intensity of doxorubicin decreased to 12% after 24 hours culture but that of Lipodox remained at 81%. In an orthotopic model, the average tumor weight and survival were: control group: 1.0 ± 0.3 g, 25%; doxorubicin treatment group: 0.7 ± 0.05 g, 43%; and Lipodox treatment group: 0.2 ± 0.1 g, 57%. ConclusionOur study demonstrated that Lipodox can enhance doxorubicin cytotoxicity in bladder cancer cells and inhibit tumor growth in orthotopic bladder cancer with improved survival rate. Therefore, we suggest Lipodox may act as an alternative to doxorubicin in the treatment of local bladder cancer.

Anti-tumor effect of Radix Paeoniae Rubra extract on mice bladder tumors using intravesical therapy.

Radix Paeoniae Rubra (RPR) is the dried root of Paeonia lactiflora Pallas and Paeonia veitchii Lynch, and is a herbal medicine that is widely used in traditional Chinese medicine for the treatment of blood-heat and blood-stasis syndrome, similarly to Cortex Moutan. The present study identified the same three components in RPR and Cortex Moutan extracts. In addition, it has been reported that RPR has an anti-cancer effect. Bladder cancer is the seventh most common type of cancer worldwide. Due to the high recurrence rate, identifying novel drugs for bladder cancer therapy is essential. In the present study, RPR extract was evaluated as a bladder cancer therapy in vitro and in vivo. The present results revealed that RPR extract reduced the cell viability of bladder cancer cells with a half maximal inhibitory concentration of 1–3 mg/ml, and had an extremely low cytotoxic effect on normal urothelial cells. Additionally, RPR decreased certain cell cycle populations, predominantly cells in the G1 phase, and caused a clear sub-G increase. In a mouse orthotopic bladder tumor model, intravesical application of RPR extract decreased the bladder tumor size without altering the blood biochemical parameters of the mice. In summary, the present results demonstrate the anti-proliferative properties of RPR extract on bladder cancer cells, and its anti-bladder tumor effect in vivo. Compared to Cortex Moutan extract, RPR extract may provide a more effective alternative therapeutic strategy for the intravesical therapy of superficial bladder cancer.

Metformin can block precancerous progression to invasive tumors of bladder through inhibiting STAT3-mediated signaling pathways.

BackgroundMetformin is the first line of oral antidiabetic drug in the biguanide class for treatment of type 2 diabetes. Increasing evidence has suggested that it is a potential anti-tumor drug. However, the mechanisms underlying inhibiting tumor development remain elusive, especially in bladder tumors.MethodsT24 and J82 cell lines were used as an in vitro model, and 24 female SD rats were used to build an N-methyl-N-nitrosourea (MNU)-induced orthotopic rat bladder cancer model. Transfection of lentivirus-based shRNA was used to construct the STAT3-KNOCKDOWN T24 cell line. After metformin treatment, the viability of bladde cancer cells was determined by CCK8. Cell cycle distribution and apoptosis were assessed by flow cytometry. The migration and invasion abilities of cells were evaluated by wound healing and transwell asssays. The inactivation of stat3 pahtway was examined by qRTPCR, western blot and Immunofluorescence.ResultsMetformin can effectively inhibit precancerous progression to invasive cancer in an MNU-induced rat orthotopic bladder tumor model, although it could not completely suppress normal cells transforming into tumor cells. While the MNU could induce 50 % rats (4/8) to develop invasive bladder cancers, the rats co-administrated with metformin failed to develop invasive tumors but retained at precancerous or non-invasive stages, exhibiting as dysplasia, papillary tumor and/or carcinoma in situ (CIS). Accordingly, phosphorylation of signal transducer and activator of transcription 3 (STAT3), which is a well known oncogene, was significantly inhibited in the tumors of rats treated with metformin. In vitro experiments revealed that the metformin could efficiently inhibit STAT3 activation, which was associated with the cell cycle arrest, reduction of cell proliferation, migration and invasiveness, and increase in apoptotic cell death of bladder cancer cell lines.ConclusionsThese findings provide for the first time the evidence that metformin can block precancerous lesions progressing to invasive tumors through inhibiting the activation of STAT3 pathway, and may be used for treatment of the non-invasive bladder cancers to prevent them from progression to invasive tumors.Electronic supplementary materialThe online version of this article (doi:10.1186/s13046-015-0183-0) contains supplementary material, which is available to authorized users.

P70S6K and Elf4E dual inhibition is essential to control bladder tumor growth and progression in orthotopic mouse non-muscle invasive bladder tumor model.

We investigated how the dual inhibition of the molecular mechanism of the mammalian target of the rapamycin (mTOR) downstreams, P70S6 kinase (P70S6K) and eukaryotic initiation factor 4E (eIF4E), can lead to a suppression of the proliferation and progression of urothelial carcinoma (UC) in an orthotopic mouse non-muscle invasive bladder tumor (NMIBT) model. A KU-7-luc cell intravesically instilled orthotopic mouse NMIBC model was monitored using bioluminescence imaging (BLI) in vivo by interfering with different molecular components using rapamycin and siRNA technology. We then analyzed the effects on molecular activation status, cell growth, proliferation, and progression. A high concentration of rapamycin (10 µM) blocked both P70S6K and elF4E phosphorylation and inhibited cell proliferation in the KU-7-luc cells. It also reduced cell viability and proliferation more than the transfection of siRNA against p70S6K or elF4E. The groups with dual p70S6K and elF4E siRNA, and rapamycin reduced tumor volume and lamina propria invasion more than the groups with p70S6K or elF4E siRNA instillation, although all groups reduced photon density compared to the control. These findings suggest that both the mTOR pathway downstream of eIF4E and p70S6K can be successfully inhibited by high dose rapamycin only, and p70S6K and Elf4E dual inhibition is essential to control bladder tumor growth and progression.

Enhanced efficacy of ALT-803, an IL-15-based superagonist complex, in combination with immune checkpoint inhibitors in an orthotopic muscle invasive bladder tumor model in mice

Meeting abstracts Immune checkpoint therapy, which can target regulatory pathways of T cells to enhance antitumor immune responses, has led to important clinical advances and provides novel strategies for combination immunotherapies against cancer. ALT-803 is an IL-15 superagonist complex capable

Abstract B24: ATDC (Trim29) drives invasive bladder cancer formation

Abstract Bladder cancer is a common and deadly malignancy, but incomplete understanding of the molecular events driving tumor development and metastasis has limited development of effective treatments. Ataxia-Telangiectasia Group D Complementing (ATDC; also named TRIM29) is highly expressed in many cancer types, including bladder and pancreas. To determine the role of ATDC in tumorigenesis, we developed a novel transgenic mouse model in which ATDC was overexpressed in multiple tissue types. The dominant phenotype in these mice was the development of both papillary and invasive bladder carcinoma beginning at approximately 8 months of age. In this model, invasive bladder tumors were histologically indistinguishable and shared a similar gene expression signature with human invasive bladder cancers. We also found that ATDC was highly expressed in ~70% human bladder cancers where it marked invasive tumors and correlated with worse survival after chemotherapy (p = 0.002). Furthermore, ATDC knockdown decreased proliferation, invasion and tumor growth in multiple human bladder cancer cell lines and in an in vivo orthotopic bladder tumor model. ATDC-induced bladder tumorigenesis was mediated by upregulation of DNA methyltransferase 3A (DNMT3A), which drove PTEN promoter methylation and silencing, events which promoted invasion and proliferation in both transgenic mice and human bladder cancers. These findings establish ATDC as a novel driver and therapeutic target in bladder cancer. In addition, the ATDC transgenic mouse model should serve as an important and unique new model to study bladder cancer development, progression and therapeutic responses. Citation Format: Phillip Palmbos, Lidong Wang, Huibin Yang, Jake LeFlein, John E. Wilkinson, Chandan Kumar-Sinha, L. Priya Kunju, Stephanie Daignault, Xue-Ru Wu, Yair Lotan, Monica Liebert, Mats Ljungman, Diane Simeone. ATDC (Trim29) drives invasive bladder cancer formation. [abstract]. In: Proceedings of the AACR Special Conference: The Translational Impact of Model Organisms in Cancer; Nov 5-8, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(11 Suppl):Abstract nr B24.

Abstract 3127: The effect of Guizhi Fuling Wan (GFW) on bladder tumor growth in a mouse model

Abstract Bladder cancer is the second most common malignancy of the genitourinary tumors in the world and tenth most common cancer in Taiwan. The most common type of bladder cancer is urothelial carcinoma (UC, formerly known as transitional cell carcinoma, TCC). The incidence rate is particularly high in southwestern coast of Taiwan. Treatment for superficial non-invasive bladder carcinoma is currently using intravesical chemotherapy with mitomycin C and BCG after transurethral resection of bladder tumor (TUR-BT). However, this therapy usually causes adverse effects including urinary frequency, urinary urgency, hematuria and tuberculosis infection. Therefore, we intend to find a complementary and alternative medicine for bladder cancer treatment which can bring a good result with less side effects. In our previous study, we found that a traditional Chinese Medicine (TCM), Guizhi Fuling Wan (GFW) had an effect on growth inhibition of human bladder cancer cell lines as same as mitomycin-C, doxorubicin and cisplatin, but had mild toxicicity on normal human bladder epithelial cells. In this study we investigated whether GFW could be used as an intravesical chemotherapy agent in our orthotopic bladder cancer mouse model and compared its adverse effect with mitomycin-C and BCG. A mouse bladder cancer cell line, MB49, was selected and evaluated its response to GFW treatment. Cell Counting Kit-8 (CCK-8) assay was employed to analyze cell viability and flow cytometry was used to determine cell cycle and apoptosis. MB49 cells were implanted into female C57BL/6 mice to generate our orthotopic bladder tumor model which was confirmed under a microscope in histology by hematoxylin and eosin staining. Our data showed that GFW was a potent inhibitor of the proliferation of mouse bladder cancer cells in vitro as well as inhibited the tumor growth on MB49 bladder cancer orthotopic model. In addition, bladder hemorrhage which was observed in bladder cancer mice had completely disappeared 17 days after the intravesical GFW-treatment. These results support GFW as a strong candidate for intravesicle chemotherapy against bladder cancer. Citation Format: Chi-Chen Lu, Ling-Huei Tseng, Syue-Yi Chen, Jiann-Der Wu, Shu-Fen Wu, Michael W.Y. Chan, Yu-Wei Leu, Cheng-Da Hsu. The effect of Guizhi Fuling Wan (GFW) on bladder tumor growth in a mouse model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3127. doi:10.1158/1538-7445.AM2014-3127

Anti-tumor effects of anti-PD-L1 therapy in an orthotopic bladder tumor model

Meeting abstracts Antibodies that block PD-1/PD-L1 interactions have shown efficacy against both lung and skin cancers in early-stage clinical trials, and may also be effective in other tumor types, particularly bladder tumors. PD-L1 expression has been previously reported to correlate with high-