Treatment Of Bladder Cancer Research Articles

Evaluating a combination treatment of NK cells and reovirus against bladder cancer cells using an in vitro assay to simulate intravesical therapy

Intravesical treatment using either reovirus or natural killer (NK) cells serves as an efficient strategy for the treatment of bladder cancer cells (BCCs); however, corresponding monotherapies have often shown modest cytotoxicity. The potential of a locoregional combination using high-dose reovirus and NK cell therapy in an intravesical approach has not yet been studied. In this study, we evaluated the effectiveness of reoviruses and expanded NK cells (eNK) as potential strategies for the treatment of bladder cancer. The anti-tumor effects of mono-treatment with reovirus type 3 Dearing strain (RC402 and RP116) and in combination with interleukin (IL)-18/-21-pretreated eNK cells were investigated on BCC lines (5637, HT-1376, and 253J-BV) using intravesical therapy to simulate in vitro model. RP116 and IL-18/-21-pretreated eNK cells exhibited effective cytotoxicity against grade 1 carcinoma (5637 cells) when used alone, but not against HT-1376 (grade 2 carcinoma) and 253J-BV cells (derived from a metastatic site). Notably, combining RP116 with IL-18/-21-pretreated eNK cells displayed effective cytotoxicity against both HT-1376 and 253J-BV cells. Our findings underscore the potential of a combination therapy using reoviruses and NK cells as a promising strategy for treating bladder cancer.

Correlation between Ki-67 or Profilin-1 Expression Levels, Clinicopathological Characteristics and Postoperative Prognosis in Patients with Bladder Cancer.

Bladder cancer is the most common malignancy of the urinary system, and the search for new and reliable biomarkers has important clinical significance for the personalized treatment of bladder cancer. This study aims to explore the correlation between nuclear proliferation antigen (Ki-67) or Profilin-1 (PFN1) levels, clinicopathological characteristics, and postoperative prognosis in patients with bladder cancer. Patients with bladder cancer who underwent transurethral resection of bladder cancer tumor in The Fourth Affiliated Hospital of Soochow University, hospital from January 2019 to January 2021 were selected as the study group (n = 60), and patients with benign lesions of bladder cancer during the same period were selected as the control group (n = 60). The expression of Ki-67 and PFN1 in tumor and bladder tissues of the two groups was analyzed. Ki-67 recorded the patient's pathological parameters and calculated the patient's postoperative prognosis. The correlation between Ki-67 and PFN1 expression levels, pathological parameters, and postoperative prognosis was analyzed. The positive expression rates of Ki-67 and PFN1 in the study group were 63.33% and 73.33%, respectively, which were significantly higher than the positive expression rates in the control group (χ2 = 14.803, 17.757, p < 0.001). The positive expression rates of Ki-67 and PFN1 were related to histological grade, clinical stage, infiltration, and lymph node metastasis, and the differences were statistically significant (p < 0.05). Bladder cancer patients with non muscle-invasive bladder cancer (NMIBC), high-grade histological grade, Ta~T1 clinical stage, invasive, and lymph node metastasis have a higher Ki-67 positive expression rate than bladder cancer patients with muscle-invasive bladder cancer (MIBC), low-grade histological grade, T2~T4, non-invasive, and no lymph node metastasis. The high expression level of Ki-67 has little relationship with gender, age, tumor diameter, and vascular invasion (p > 0.05). The survival time and three-year survival rate of the Ki-67 positive expression group were significantly lower than those of the Ki-67 negative expression group (p < 0.05). The survival time and three-year survival rate of the PFN1 positive expression group were significantly lower than those of the PFN1 negative expression group (p < 0.05). The positive expression rates of Ki-67 and PFN1 in bladder tumor tissue are significantly higher than those in bladder tissue, and pathological pattern, histological grade, clinical stage, infiltration, and lymph node metastasis are related to the positive expression rates of Ki-67 and PFN1, and different genders, ages, tumors diameter and vascular invasion are not related to the positive expression rates of Ki-67 and PFN1. The survival time and three-year survival rates of bladder cancer patients with Ki-67 positive and PFN1 positive expression are shorter.

Comparison of red and green light for treating non-muscle invasive bladder cancer in rats using singlet oxygen-cleavable prodrugs with PPIX-PDT.

It has been 30 years since Photofrin-PDT was approved for the treatment of bladder cancer in Canada. However, Photofrin-PDT failed to gain popularity due to bladder complications. The PDT with red light and IV-administered Photofrin could permanently damage the bladder muscle. We have been developing a new combination strategy of PpIX-PDT with singlet oxygen-cleavable prodrugs for NMIBC with minimal side effects, avoiding damage to the bladder muscle layer. PpIX can be excited by either green (532 nm) or red (635 nm) light. Red light could be more efficacious invivo due to its deeper tissue penetration than green light. Since HAL preferentially produces PpIX in tumors, we hypothesized that illuminating PpIX with red light might spare the muscle layer. PpIX-PDT was used to compare green and red laser efficacy invitro and invivo. The IC50 of invitro PpIX-PDT was 18 mW/cm2 with the red laser and 22 mW/cm2 with the green laser. The invivo efficacy of the red laser with 50, 75, and 100 mW total dose was similar to the same dose of green laser in reducing tumor volume. Combining PpIX-PDT with prodrugs methyl-linked mitomycin C (Mt-L-MMC) and rhodamine-linked SN-38 (Rh-L-SN-38) significantly improved efficacy (tumor volume comparison). PpIX-PDT or PpIX-PDT + prodrug combination did not cause muscle damage in histological analysis. Overall, a combination of PpIX-PDT and prodrug with 635 nm laser is promising for non-muscle invasive bladder cancer treatment.

Disitamab Vedotin Alone or in Combination With Immune Checkpoint Inhibitors in Bladder-Sparing Treatment of Muscle-Invasive Bladder Cancer: A Real-World Study

PurposeTo evaluate the efficacy and safety of a novel humanized anti-HER2 antibody, RC48-ADC (Disitamab vedotin, DV), the combination of RC48-ADC with PD-1 inhibitors was used to treat muscle-invasive bladder cancer (MIBC). This combination therapy has potential applications in both bladder preservation and neoadjuvant therapy for MIBC. MethodsPatients with MIBC underwent transurethral resection of bladder tumors followed by RC48-ADC alone or in combination with PD-1 inhibitors. Radiological and endoscopic evaluations were conducted 3 months later. The primary endpoint was objective response rate (ORR), with secondary endpoints including complete response rate (CR), partial response rate (PR), and bladder preservation rate. Treatment safety was assessed according to RECIST v1.1 criteria. ResultsEleven patients were enrolled, with a median follow-up of 19.0 months. Nine patients achieved objective response, including 6 CR and 3 PR cases. The pathological ORR was 81.8%. Eight patients continued combined treatment after 3 months, maintaining a 72.7% bladder preservation rate at 16 months. One elderly patient progressed from ypT2N0M0 to ypT3N0M0 and underwent radical cystectomy but had no recurrence or metastasis 12 months postoperation. All patients reported varying degrees of treatment-related adverse reactions, which were largely manageable. ConclusionThe combination of RC48-ADC and PD-1 inhibitors proves to be a viable and safe option for bladder-sparing therapy, particularly for T2-stage MIBC patients who are ineligible for surgery and chemotherapy. This approach offers a promising new direction for bladder preservation or neoadjuvant therapy in MIBC patients.

Electrospun nanofibrous mats loaded with gemcitabine and cisplatin suppress bladder tumor growth by improving the tumor immune microenvironment

The perplexing issues related to positive surgical margins and the considerable negative consequences associated with systemic chemotherapy have posed ongoing challenges for clinicians, especially when it comes to addressing bladder cancer treatment. The current investigation describes the production of nanocomposites loaded with gemcitabine (GEM) and cisplatin (CDDP) through the utilization of electrospinning technology. In vitro and in vivo studies have provided evidence of the strong effectiveness in suppressing tumor advancement while simultaneously reducing the accumulation of chemotherapy drugs within liver and kidney tissues. Mechanically, the GEM and CDDP-loaded electrospun nanocomposites could effectively eliminate myeloid-derived suppressor cells (MDSCs) in tumor tissues, and recruit CD8+ T cells and NKp46+ NK cells to kill tumor cells, which can also effectively inhibit tumor microvascular formation. Our investigation into the impact of localized administration of chemotherapy through GEM and CDDP-loaded electrospun nanocomposites on the tumor microenvironment will offer novel insights for tackling tumors.Graphical abstractDrug-loaded electrospun nanofibrous mats suppress bladder tumor growth by improving the tumor immune microenvironment.

Abstract 1827: Exploring the feasibility and pharmacological mechanism of bufadienolides for the treatment of non-muscle invasive bladder cancer

Abstract The majority of diagnosed bladder cancer (BC) patients is presenting with non-muscle-invasive bladder cancer (NMIBC). Although NMIBC generally exhibits a favorable prognosis, a considerable number of patients suffer from short-term recurrence, and high risks of progression to the more aggressive muscle-invasive bladder cancer (MIBC). Therefore, there is an urgent need for innovative treatments to improve outcomes for patients with NMIBC. For centuries, traditional Chinese medicine (TCM) has played a significant role in Asian society, with ongoing research to investigate the intricate relationship between TCM and treatment of cancers. Bufadienolides, the principal active components in Chansu, are derived from the aqueous extract of the parotoid glands and the dried secretion of the Asiatic toad. Bufadienolides have been reported to demonstrate significant antitumor and anti-inflammatory activities. This study aims to evaluate the feasibility and elucidate the pharmacological mechanisms that underlie the anticancer effects of bufadienolides in NMIBC. Our experiments show that bufadienolides significantly decrease cell viability, induce cell-cycle arrest at the sub-G1 phase, and activate apoptosis in NMIBC cells (RT112 and RT4). Protein analysis reveals the activation of apoptosis-related proteins (PARP, caspase-3, -8, -9) by bufadienolides in NMIBC cells. In conclusion, our findings suggest that bufadienolides present promising potential as therapeutic agents for NMIBC treatment. Citation Format: Chih-Chieh Tu, Mei-Chuan Chen, Chun-Han Chen. Exploring the feasibility and pharmacological mechanism of bufadienolides for the treatment of non-muscle invasive bladder cancer [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 1827.

Abstract 2029: Investigation of anti-tumor activity of porcine myeloperoxidase for urothelial carcinoma of the bladder

Abstract Introduction: Porcine myeloperoxidase (pMPO) is a cationic enzyme secreted by granulocytic leukocytes capable of selectively binding cancer cells due to their negative surface charge. In the presence of hydrogen peroxide (H2O2) and sodium chloride (NaCl), MPO catalyzes the production of electronically excited singlet molecular oxygen, which exerts focused cytotoxic activity against cancer cells. Methods: Human bladder non-cancer (SV-HUC1) and cancer cells (T24 and 5637) were used to assess differential cytotoxic activity of pMPO. pMPO was combined with associated reagents, including H2O2, NaCl, and L-proline and glycine for 45 minutes to support the generation of singlet oxygen. MTS assay was used to assessed cell viability at day 3 post-treatment. Non-cancer and cancer cells were labeled with GFP and mCherry, respectively, via infection with lentivirus and cultured in tandem to allow for simultaneous treatment of both cell types. After the treatment, flow cytometry and microscopy were used to monitor the growth of the cells. Results: No cytotoxicity was noted when SV-HUC1 cells were cultured with individual reagents pMPO, NaCl, L-Proline, or Glycine, and limited cytotoxicity was observed with H2O2. Notably, cell viability was nearly maximally preserved for SV-HUC1 cells. The combination of pMPO with associated reagents resulted in killing of 5637 and T24 cells, with tumoricidal activity maintained across increasing tumor cell density, with cell viability preserved for SV-HUC1 cells. Within the cell co-culture system, simultaneous treatment of both cell types with the pMPO treatment resulted in selective killing of tumor cells and preservation of SV-HUC1 cells. Mechanistic studies confirm specificity of pMPO binding to tumor cells, and further, high levels of expression of gammaH2AX and phospho-ATM in 5637 and T24 cells following treatment. Conclusion: pMPO demonstrates selective and efficient killing of bladder cancer cells with minimal cytotoxicity against non-cancer urothelial cells. Given its reliance on direct surface contact with tumor cells for activity, pMPO may be developed as an intravesical therapy for treatment of non-muscle invasive bladder cancers. Acknowledgements: This work was partially supported by Mayo funds provided to Dr. Haojie Huang. Citation Format: Junnan Liu, Robert C. Allen, Jackson T. Stephens, Paras Shah, Haojie Huang. Investigation of anti-tumor activity of porcine myeloperoxidase for urothelial carcinoma of the bladder [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 2029.

Abstract 1916: Discovery of a novel Nectin4 IPSC-derived cell therapy for the treatment of solid tumors

Abstract Century Therapeutics is developing a Nectin4-targeting IPSC-derived cell therapy for the treatment of Nectin4 expressing solid tumors. The Nectin proteins (Nectin1, Nectin2, Nectin3 and Nectin4) are members of the calcium independent immunoglobulin superfamily of cell adhesion molecules (CAMs) involved in adhesive processes that help in the growth and development of tissues. Nectin 1, 2 and 3 are normally found in adult tissue whereas Nectin4 is mainly found in normal placental and embryonic tissue. Nectin4 is also expressed in different types of cancer including urothelial, ovarian, lung and head/neck cancers. Nectin4 is established as a biomarker for worse prognosis in cancers and is linked with carcinogenesis and disease severity. These features establish Nectin4 as a promising target for anti-tumor drug development. Enfortumab vedotin, an antibody drug conjugate targeting Nectin4 positive tumors, has demonstrated benefit in clinical trials and is FDA approved for treatment of advanced bladder cancer. We have identified novel single-domain antibodies (VHH) that bind to multiple epitopes on Nectin4 extracellular domain. The VHH antibodies were engineered into chimeric antigen receptor (CAR) formats and characterized for expression, cell activation through antigen engagement, and cytotoxicity activity in primary T-cells. Selected binders demonstrated efficacy in multiple CAR formats in primary T-cells in a mouse xenograft model using OVCar-3 tumor cells. The lead CARs engineered into primary T-cells demonstrated tumor inhibition similar to a reference CAR using the ASG-5ME antibody (Enfortumab) as the Nectin4 binder. The CARs were engineered into our IPSC-derived iNK and iT cells and demonstrated cytotoxicity activity against a panel of cell lines with a range of cell surface expression of Nectin4. Based on these studies, Century Therapeutics is advancing the lead Nectin4 binder for development of an IPSC-derived cell therapy to treat Nectin4 positive solid tumors. Citation Format: Jill M. Carton, Chris Dower, Michael Miller, John Wheeler, Sean Heron, Hillary J. Millar, David Walker, Daniel J. Perry, Andriana Lebid, Luis Cocka, Dae Hwan Kim, Barry Morse, Buddha Gurung, Maisha Harris, Annalise Jethon, Michael Naso, Hy Levitsky. Discovery of a novel Nectin4 IPSC-derived cell therapy for the treatment of solid tumors [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 1916.

Abstract 1820: Investigating the anticancer effects and pharmacological mechanisms of phenanthridine Amaryllidaceae alkaloid in bladder cancer

Abstract Bladder cancer (BC) ranks as the tenth most common malignancy worldwide. Despite the improved five-year survival rate of around 80% for bladder cancer patients, 25% of cases progress to muscle-invasive bladder cancer with associated metastases, leading to a notable five-year survival of 5%. This underscores the urgent clinical necessity for the development of novel therapeutic strategies in the management of bladder cancer. In this study, we demonstrate the anticancer potential of a phenanthridine Amaryllidaceae alkaloid (PAA), and investigate its underlying mechanisms in bladder cancer. The data demonstrates the selective cytotoxicity of PAA towards bladder cancer cells, revealing IC50 values of 2.47 μM in RT112 cells and 8.99 μM in normal uroepithelial SV-HUC-1 cells. Protein array analysis further showed that PAA attenuated phosphorylation of several kinases, which functions as critical regulators of cell survival and proliferation. PAA induces S phase retardation and increases the phosphorylation of ATM, potentially enhancing DNA damage capability. Furthermore, PAA induced apoptosis, as evidenced by the accumulation of sub-G1 cells and caspase activation. In summary, our findings demonstrate that PAA exerts diverse effects on cell cycle regulation and apoptosis. These results suggest that PAA holds promise as a potential candidate for the treatment of bladder cancer. Citation Format: Yu-Chi Su, Mei-Chuan Chen. Investigating the anticancer effects and pharmacological mechanisms of phenanthridine Amaryllidaceae alkaloid in bladder cancer [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 1820.

Abstract 2462: Live attenuated Salmonella ZH9 as novel microbial immunotherapy for the treatment of bladder cancer

Abstract Microbial immunotherapy with Bacillus Calmette-Guérin (BCG) has been the standard-of-care for non-muscle invasive bladder cancer (NMIBC) for over 30 years. Today, global demand for BCG exceeds supply, leaving many patients untreated. BCG is associated with high disease recurrence and presents high treatment burden for patients. There remains therefore significant unmet need for novel therapeutic approaches for NMIBC and we sought to establish the utility of the live-attenuated Salmonella enterica Typhi ZH9 as a more effective microbial immunotherapy. Efficacy of ZH9 was established in orthotopic, syngeneic, mouse MB49 tumor models in which animals were treated in the bladder via catheterization, with or without prior subcutaneous immune priming. Immune responses were measured by flow cytometry and Nanostring transcriptomic analyses of bladder tissues. An intravesical dose of ZH9 after orthotopic MB49 tumour inoculation demonstrated significant survival benefit compared to both vehicle control and equivalent colony forming unit (CFU) BCG treatments. Repeat, weekly dosing studies showed a single administration of ZH9 was sufficient for maximum efficacy. To explore the durability of protection, surviving intravesical ZH9 treated animals were rechallenged, demonstrating protection from both bladder and subcutaneous MB49 tumors suggestive of lasting local and systemic anti-tumor immunity. Flow cytometry analysis of bladders showed that intravesical ZH9 treatment resulted in cellular immune response characterised by recruitment of NK cells, CD4+ and CD8+ T cells, and dendritic cells with an activated, cross-presenting phenotype, in all cases of greater magnitude than after treatment with an equivalent dose of BCG. Based on observations that pre-existing immunity to BCG has been associated with improved outcomes to intravesical BCG therapy in NMIBC, we explored whether systemic priming with ZH9 benefits local bladder therapy. Systemic prime with ZH9 followed by a single intravesical dose of ZH9 showed a trend for improved survival and will be explored in the clinical setting. This systemic immune priming effect was associated with enhanced local bladder immune cell infiltrates and the upregulation of more than 150 immune response genes in the bladder compared to intravesical therapy alone. These data form the basis of preclinical package accepted by the FDA for a Phase 1/1b study evaluating the safety, pharmacology, and clinical effect of ZH9 treatment in patients with NMIBC, currently recruiting patients. The investigation includes thorough translational and biomarker studies to delve into the mechanism of action of ZH9 and explore patient stratification approaches. By easing the treatment burden on patients, lowering healthcare costs, and featuring a scalable manufacturing process, ZH9 has the potential to revolutionize the treatment paradigm in NMIBC and reshape the patient journey. Citation Format: Nicholas Glanville, Oluwatobiloba Oke, Claudia Prevosto, Alexandra Sevko, Andrew Scott, Sonia Domingos-Pereira, Lenka Polak, Denise Nardelli-Haefliger, Livija Deban. Live attenuated Salmonella ZH9 as novel microbial immunotherapy for the treatment of bladder cancer [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 2462.

Abstract 5640: Unlocking the therapeutic potential of SF3B1 inhibitors for bladder cancer treatment

Abstract RNA splicing dysregulation is a hallmark of cancer, occurring in multiple solid and hematological malignancies. Splicing factor 3 subunit B1 (SF3B1), a key component of the U2 small nuclear ribonucleoprotein (snRNP) complex that regulates RNA splicing, is frequently altered in a variety of cancer types, including non-muscle-invasive and muscle-invasive bladder cancer, where the E902K mutation is common. In this study, we investigated the therapeutic potential of the SF3B1 inhibitor, pladienolide B, in bladder cancer using in vitro models. We used a recombinant plasmid containing the SF3B1E902K mutation and established an UMUC3E902K mutant urothelial cell line. Both UMUC3WT and UMUC3E902K cells were treated with pladienolide B alone or in combination with cisplatin to evaluate differences in cell viability. Flow cytometry using annexin V staining and propidium iodide exclusion was utilized to assess the cell death mechanism. RNAseq was performed after RNA extraction from UMUC3WT, UMUC3E902K, RT4, and HT1376 bladder cancer cell lines were treated with pladienolide alone or combined with cisplatin. We determined that the IC50 for pladienolide B is 5nM for UMUC3 cells observed 72 hours post-treatment. Treatment with pladienolide B halted the cell cycle and caused cell death by apoptosis for both UMUC3WT and UMUC3E902K cell lines. We also observed that UMUC3E902K cells were significantly more sensitive to pladienolide B compared to UMUC3WT cells (p≤0.05). Furthermore, there was a synergistic effect observed after co-treatment with low-dose pladienolide B (2 nM) and cisplatin (3 µM) for both UMUC3WT and UMUC3E902K cell lines, with UMUC3E902K cells showing greater sensitivity to combination treatment. Our results provide insights into the potential use of splicing inhibitors, alone or in combination with chemotherapy, for treating bladder cancer, specifically for tumors that bear driver mutations in splicing factors. Currently, we are evaluating the mechanism by which SF3B1 mutations make cells sensitive to pladienolide B in vitro and in vivo, with the goal of identifying specific mRNA splicing vulnerabilities that can be targeted by anti-sense or splice-switching oligonucleotides to achieve anti-tumor outcomes. Additional differential splicing patterns and preliminary in vivo results will be presented. Citation Format: Rod Carlo Columbres, Arup Chakraborty, Andrea Apolo, Rouf Banday. Unlocking the therapeutic potential of SF3B1 inhibitors for bladder cancer treatment [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 5640.

Abstract 6899: Enfortumab vedotin (EV): Efficacy comparison with trastuzumab deruxtecan (T-DXd) and sacituzumab govitecan (SG) and its potential for combination benefit in bladder cancer XPDX models

Abstract EV is a Nectin-4 targeting antibody-drug conjugate (ADC) with an MMAE payload, recently approved for bladder cancer treatment. We established and characterized 18 bladder XPDX models representing primary and metastatic disease from naïve or clinically treated patients, some with actionable mutations. To better understand the potential additive benefit of EV in bladder cancer, we evaluated the ADC alone and in combination with agents targeting ERBB2, PIK3CA or FGFR3. In addition, we tested EV alone in ST5420B, a model established from a patient who progressed on EV after five cycles, as well as ST975B, a model which harbors a novel NECTIN4 fusion. 18 bladder XPDX models were established in immune-deficient mice, including 5 from newly diagnosed patients (2 from primary site), and 13 from recurrent disease (2 from primary site). Nectin-4, Trop2 protein and ERBB2 receptor expression was tested, and models profiled using WES and RNAseq. For in vivo studies, all models were evaluated against cisplatin, T-DXd, SG, and EV. Models with actionable mutations were tested with alpelisib, erdafitinib, and neratinib alone and in combination with EV. Endpoints in all studies included tumor volume and time from treatment initiation with %T/C values and tumor regression reported at study completion; a %T/C of ≤ 20% versus control was considered sensitive. Tumor regression (%T/C&amp;lt;0%) versus Day 0 tumor volume was also reported. Most models stained positive for Nectin-4 and Trop-2. FGFR3 variants were found in five models and ERBB2 mutations in two while several models reported PIK3CA variants; deletions in RB1 and CDKN2A were common. In vivo studies reported differential responses to cisplatin with the most sensitive models established from treatment-naïve patients. EV and SG tested alone reported activity in several models; EV added benefit in some combination treatments. We have characterized a panel of bladder XPDX models and benchmarked them against T-DXd, EV and SG alone and EV in combination with targeted therapies. This data is a valuable tool in further developing EV and identifying novel therapies for bladder cancer. Citation Format: Johnnie Flores, Heaven Sessions, Alyssa Simonson, Natalia Banos, Tahmineh Rouzbahani, Armando Diaz III, Jim Lund, Emiliano Calvo, Victor Moreno, Kyriakos Papadopoulos, Drew Rasco, Amita Patnaik, Scott Ulmer, Luis Rodriguez, Michael Wick. Enfortumab vedotin (EV): Efficacy comparison with trastuzumab deruxtecan (T-DXd) and sacituzumab govitecan (SG) and its potential for combination benefit in bladder cancer XPDX models [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 6899.

COVID-19 impact on bladder cancer treatment

COVID-19 impact on bladder cancer treatment

Development of high-efficiency superparamagnetic drug delivery system with MPI imaging capability.

In this study, a high-efficiency superparamagnetic drug delivery system was developed for preclinical treatment of bladder cancer in small animals. Two types of nanoparticles with magnetic particle imaging (MPI) capability, i.e., single- and multi-core superparamagnetic iron oxide nanoparticles (SPIONs), were selected and coupled with bladder anti-tumor drugs by a covalent coupling scheme. Owing to the minimal particle size, magnetic field strengths of 270mT with a gradient of 3.2T/m and 260mT with a gradient of 3.7T/m were found to be necessary to reach an average velocity of 2mm/s for single- and multi-core SPIONs, respectively. To achieve this, a method of constructing an in vitro magnetic field for drug delivery was developed based on hollow multi-coils arranged coaxially in close rows, and magnetic field simulation was used to study the laws of the influence of the coil structure and parameters on the magnetic field. Using this method, a magnetic drug delivery system of single-core SPIONs was developed for rabbit bladder therapy. The delivery system consisted of three coaxially and equidistantly arranged coils with an inner diameter of Φ50mm, radial height of 85mm, and width of 15mm that were positioned in close proximity to each other. CCK8 experimental results showed that the three types of drug-coupled SPION killed tumor cells effectively. By adjusting the axial and radial positions of the rabbit bladder within the inner hole of the delivery coil structure, the magnetic drugs injected could undergo two-dimensional delivery motions and were delivered and aggregated to the specified target location within 12s, with an aggregation range of about 5mm × 5mm. In addition, the SPION distribution before and after delivery was imaged using a home-made open-bore MPI system that could realistically reflect the physical state. This study contributes to the development of local, rapid, and precise drug delivery and the visualization of this process during cancer therapy, and further research on MPI/delivery synchronization technology is planned for the future.

Patterns of treatment of high-risk BCG-unresponsive non-muscle invasive bladder cancer (NMIBC) patients among Arab urologists.

To understand the treatment plans suggested for BCG-unresponsive non-muscle invasive disease (NMIBC) patients in the Arab countries and therapeutic decisions applied for BCG-naive patients during BCG shortage time. A 10-minute online survey was distributed through the Arab Association of Urology (AAU) office to urologists in the Arab countries who treat patients with NMIBC. One hundred six urologists responded to the survey. The majority of urologists had treated, in the past 6 months, > 10 patients with NMIBC who were considered BCG-unresponsive (55% of respondents). Radical cystectomy (RC) was the most popular treatment option (recommended by 50%) for these patients. This was followed by intravesical chemotherapy (30%), repeat BCG therapy (12%), resection with ongoing surveillance (8%). Clinical trials and intravenous checkpoint inhibitors were never selected. The most preferred intravesical chemotherapy was by ranking: 60% gemcitabine, 19% mitomycin C, 8% docetaxel, 8% gemcitabine/docetaxel, 4% sequential gemcitabine/mitomycin C, and 1% valrubicin. The use of intravesical chemotherapy appears limited by Arab urologists due to concerns regarding clinical efficacy (fear of progression) and the lack of clear recommendations by urology societies. Given the BCG shortage, which may vary per Arab country, Arab urologists have adjusted by prioritizing BCG for T1 and carcinoma in situ (CIS) patients over Ta, adapting intravesical chemotherapy, and reducing the dose/strength of BCG administered. Most physicians report an eagerness to utilize novel therapies to address the BCG deficit, especially to try intravesical chemotherapy. Even though Arab urologists are in the majority of cases selecting RC for BCG-unresponsive cases, one-third of them are most recently initiating intravesical chemotherapy as an alternative option. To further assist Arab urologists in the appropriate selection of BCG unresponsive high risk NMIBC patient treatments, enhanced education and pathway protocols are needed.

CircMCTP2 enhances the progression of bladder cancer by regulating the miR-99a-5p/FZD8 axis

BackgroundCircRNAs and miRNAs are involved in the progression of tumor. CircMCTP2 is considered as a novel tumor promoter. However, the exact functions of circMCTP2 in bladder cancer are still unclear. This study was designed to explore the underlying mechanisms of circMCTP2-modulated tumor development in bladder cancer.MethodsThe present study is an original research. The levels of circMCTP2 in a total of 39 bladder cancer specimens and cell lines were determined by RT-qPCR. The expression of FZD8 in T24 and RT-4 cells treated with miR-99a-5p mimics were examined using western blotting. In addition, the proliferative, migrative and invasive abilities of transfected cells were determined by CCK8 and Transwell assays. Furthermore, the apoptosis of transfected cells was evaluated using flow cytometry. Dual luciferase reporter assay was performed to elucidate the relationship between miR-99a-5p and circMCTP2/FZD8.ResultsThe levels of circMCTP2 were elevated in bladder cancer samples and cells, and this was related to worse survival rate. Downregulation of circMCTP2 suppressed growth and metastasis of cells, whereas the apoptotic rate of cells was enhanced. The levels of miR-99a-5rp was elevated after the downregulation of circMCTP2. Moreover, reverse correlation between the expression of miR-99a-5p and circMCTP2 was revealed in bladder cancer specimens. Additionally, FZD8 was the putative target of miR-99a-5p and the mimics of miR-99a-5p inhibited the proliferation, migration and invasion of bladder cancer cells via the FZD8/Wnt-b-catenin axis. Moreover, circMCTP2 regulated the growth and metastasis of bladder cancer cells potentially through regulating the miR-99a-5p/FZD8/Wnt-b-catenin axis. In summary, circMCTP2 was considered as an oncogenic factor through regulating the miR-99a-5p/FZD8/Wnt-b-catenin axis.ConclusionsThis novel signaling could regulate the biological behaviours of bladder cancer cells, and these findings highlighted circMCTP2 as a critical target for treating bladder cancer.

Systemic versus localized Bacillus Calmette Guérin immunotherapy of bladder cancer promotes an anti-tumoral microenvironment: Novel role of trained immunity.

Treatment for higher-risk non-muscle invasive bladder cancer (NMIBC) involves intravesical immunotherapy with Bacillus Calmette Guérin (BCG); however, disease recurrence and progression occur frequently. Systemic immunity is critical for successful cancer immunotherapy; thus, recurrence of NMIBC may be due to suboptimal systemic activation of anti-tumor immunity after local immunotherapy. We previously reported that systemically acquired trained immunity (a form of innate immune memory) in circulating monocytes is associated with increased time-to-recurrence in patients with NMIBC treated with BCG. Herein, we used a mouse model of NMIBC to compare the effects of intravesical versus intravenous (systemic) BCG immunotherapy on the local and peripheral immune microenvironments. We also assessed whether BCG-induced trained immunity modulates anti-tumor immune responses. Compared with intravesical BCG, which led to a tumor-promoting immune microenvironment, intravenous BCG resulted in an anti-tumoral bladder microenvironment characterized by increased proportions of cytotoxic T lymphocytes (CTLs), and decreased proportions of myeloid-derived suppressor cells. Polarization toward anti-tumoral immunity occurred in draining lymph nodes, spleen, and bone marrow following intravenous versus intravesical BCG treatment. Pre-treatment with intravesical BCG was associated with increased rate of tumor growth compared with intravenous BCG pre-treatment. Trained immunity contributed to remodeling of the tumor immune microenvironment, as co-instillation of BCG-trained macrophages with ovalbumin-expressing bladder tumor cells increased the proportion of tumor-specific CTLs. Furthermore, BCG-trained dendritic cells exhibited enhanced antigen uptake and presentation and promoted CTL proliferation. Our data support the concept that systemic immune activation promotes anti-tumor responses, and that BCG-induced trained immunity is important in driving anti-tumor adaptive immunity.

Securinine inhibits the tumor growth of human bladder cancer cells by suppressing Wnt/β-catenin signaling pathway and activating p38 and JNK signaling pathways

Bladder cancer (BC) is the most common malignant tumor in urinary system. Although chemotherapy is one of the most important adjuvant treatments for BC, drug resistance, non-specific toxicity and severe side effects are the major obstacles to BC chemotherapy. Natural products have always been a leading resource of antitumor drug discovery, with the advantages of excellent effectiveness, low toxicity, multi-targeting potency and easy availability.In this study, we evaluated the potential anti-tumor effect of securinine (SEC), a natural alkaloid from Securinega suffruticosa, on BC cells in vitro and in vivo, and delineated the underlying mechanism. We found that SEC inhibited the proliferation, migration and invasion, induced the apoptosis of BC cells in vitro, and retarded the xenograft tumor growth of BC cell in vivo. Notably, SEC had a promising safety profile because it presented no or low toxicity on normal cells and mice. Mechanistically, SEC inactivated Wnt/β-catenin signaling pathway while activated p38 and JNK signaling pathway. Moreover, β-catenin overexpression, the p38 inhibitor SB203580 and the JNK inhibitor SP600125 both mitigated the inhibitory effect of SEC on BC cells. Furthermore, we demonstrated a synergistic inhibitory effect of SEC and gemcitabine (GEM) on BC cells in vitro and in vivo.Taken together, our findings suggest that SEC may exert anti-BC cell effect at least through the activation of p38 and JNK signaling pathways, and the inhibition of Wnt/β-catenin signaling pathway. More meaningfully, the findings indicate that GEM-induced BC cell killing can be enhanced by combining with SEC.

Targeted Delivery of Catalase and Photosensitizer Ce6 by a Tumor-Specific Aptamer Is Effective against Bladder Cancer In Vivo.

Photodynamic therapy (PDT) is often applied in a clinical setting to treat bladder cancer. However, current photosensitizers report drawbacks such as low efficacy, low selectivity, and numerous side effects, which have limited the clinical values of PDT for bladder cancer. Previously, we developed the first bladder cancer-specific aptamer that can selectively bind to and be internalized by bladder tumor cells versus normal uroepithelium cells. Here, we use an aptamer-based drug delivery system to deliver photosensitizer chlorine e6 (Ce6) into bladder tumor cells. In addition to Ce6, we also incorporate catalase into the drug complex to increase local oxygen levels in the tumor tissue. Compared with free Ce6, an aptamer-guided DNA nanotrain (NT) loaded with Ce6 and catalase (NT-Catalase-Ce6) can specifically recognize bladder cancer cells, produce oxygen locally, induce ROS in tumor cells, and cause mitochondrial apoptosis. In an orthotopic mouse model of bladder cancer, the intravesical instillation of NT-Catalase-Ce6 exhibits faster drug internalization and a longer drug retention time in tumor tissue compared with that in normal urothelium. Moreover, our modified PDT significantly inhibits tumor growth with fewer side effects such as cystitis than free Ce6. This aptamer-based photosensitizer delivery system can therefore improve the selectivity and efficacy and reduce the side effects of PDT treatment in mouse models of bladder cancer, bearing a great translational value for bladder cancer intravesical therapy.

Bladder-cancer-derived exosomal circRNA_0013936 promotes suppressive immunity by up-regulating fatty acid transporter protein 2 and down-regulating receptor-interacting protein kinase 3 in PMN-MDSCs

BackgroundPolymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) is one of the causes of tumor immune tolerance and failure of cancer immunotherapy. Here, we found that bladder cancer (BCa)-derived exosomal circRNA_0013936 could enhance the immunosuppressive activity of PMN-MDSCs by regulating the expression of fatty acid transporter protein 2 (FATP2) and receptor-interacting protein kinase 3 (RIPK3). However, the underlying mechanism remains largely unknown.MethodsBCa-derived exosomes was isolated and used for a series of experiments. RNA sequencing was used to identify the differentially expressed circRNAs. Western blotting, immunohistochemistry, immunofluorescence, qRT-PCR, ELISA and Flow cytometry were performed to reveal the potential mechanism of circRNA_0013936 promoting the immunosuppressive activity of PMN-MDSC.ResultsCircRNA_0013936 enriched in BCa-derived exosomes could promote the expression of FATP2 and inhibit the expression of RIPK3 in PMN-MDSCs. Mechanistically, circRNA_0013936 promoted the expression of FATP2 and inhibited the expression of RIPK3 expression via sponging miR-320a and miR-301b, which directly targeted JAK2 and CREB1 respectively. Ultimately, circRNA_0013936 significantly inhibited the functions of CD8+ T cells by up-regulating FATP2 through the circRNA_0013936/miR-320a/JAK2 pathway, and down-regulating RIPK3 through the circRNA_0013936/miR-301b/CREB1 pathway in PMN-MDSCs.ConclusionsBCa-derived exosomal circRNA_0013936 promotes suppressive immunity by up-regulating FATP2 through the circRNA_0013936/miR-320a/JAK2 pathway and down-regulating RIPK3 through the circRNA_0013936/miR-301b-3p/CREB1 pathway in PMN-MDSCs. These findings help to find new targets for clinical treatment of human bladder cancer.