Approved checkpoint inhibitors in bladder cancer: which drug should be used when?

Targeting Protein Tyrosine Phosphatases to Improve Cancer Immunotherapies

Advances in immunotherapy have brought significant therapeutic benefits to many cancer patients. Nonetheless, many cancer types are refractory to current immunotherapeutic approaches, meaning that further targets are required to increase the number of patients who benefit from these technologies. Protein tyrosine phosphatases (PTPs) have long been recognised to play a vital role in the regulation of cancer cell biology and the immune response. In this review, we summarize the evidence for both the pro-tumorigenic and tumour-suppressor function of non-receptor PTPs in cancer cells and discuss recent data showing that several of these enzymes act as intracellular immune checkpoints that suppress effective tumour immunity. We highlight new data showing that the deletion of inhibitory PTPs is a rational approach to improve the outcomes of adoptive T cell-based cancer immunotherapies and describe recent progress in the development of PTP inhibitors as anti-cancer drugs.

New Nitric Oxide-Releasing Compounds as Promising Anti-Bladder Cancer Drugs

Bladder cancer is a worldwide problem and improved therapies are urgently needed. In the search for newer strong antitumor compounds, herein, we present the study of three nitric oxide-releasing compounds and evaluate them as possible therapies for this malignancy. Bladder cancer cell lines T24 and 253J were used to evaluate the antiproliferative, antimigratory, and genotoxic effects of compounds. Moreover, we determined the NF-κB pathway inhibition, and finally, the survivin downregulation exerted by our molecules. The results revealed that compounds 1 and 3 exerted a high antiproliferative activity against bladder cancer cells through DNA damage and survivin downregulation. In addition, compound 3 reduced bladder cancer cell migration. We found that nitric oxide donors are promising molecules for the development of a new therapeutic targeting the underlying mechanisms of tumorigenesis and progression of bladder cancer.

Oncology Simulation Model: A Comprehensive and Innovative Approach to Estimate and Project Prevalence and Survival in Oncology

OBJECTIVE

We demonstrate a new model framework as an innovative approach to more accurately estimate and project prevalence and survival outcomes in oncology.

METHODS

We developed an oncology simulation model (OSM) framework that offers a customizable, dynamic simulation model to generate population-level, country-specific estimates of prevalence, incidence of patients progressing from earlier stages (progression-based incidence), and survival in oncology. The framework, a continuous dynamic Markov cohort model, was implemented in Microsoft Excel. The simulation runs continuously through a prespecified calendar time range. Time-varying incidence, treatment patterns, treatment rates, and treatment pathways are specified by year to account for guideline-directed changes in standard of care and real-world trends, as well as newly approved clinical treatments. Patient cohorts transition between defined health states, with transitions informed by progression-free survival and overall survival as reported in published literature.

RESULTS

Model outputs include point prevalence and period prevalence, with options for highly granular prevalence predictions by disease stage, treatment pathway, or time of diagnosis. As a use case, we leveraged the OSM framework to estimate the prevalence of bladder cancer in the United States.

CONCLUSION

The OSM is a robust model that builds upon existing modeling practices to offer an innovative, transparent approach in estimating prevalence, progression-based incidence, and survival for oncologic conditions. The OSM combines and extends the capabilities of other common health-economic modeling approaches to provide a detailed and comprehensive modeling framework to estimate prevalence in oncology using simulation modeling and to assess the impacts of new treatments on prevalence over time.

Complete and long-lasting response to immunotherapy: A case report of urothelial cancer

INTRODUCTION

Bladder cancer is the tenth most common cancer worldwide, with Europe having the highest incidence rates. Regarding the treatment of metastatic disease, first-line treatment for fit patients is cisplatin-containing combination chemotherapy. However, a significant percentage of patients are ineligible for platinum-based chemotherapy, or progress under these regimens. Recently, immune checkpoint blockade has become a treatment option for this group of patients. In this report, we present the case of a male patient diagnosed with metastatic bladder cancer who did not tolerate cisplatin-containing chemotherapy and achieved complete response after treatment with pembrolizumab.

PATIENT CONCERNS

A 58 years-old Caucasian man with a medical history of high-grade urothelial carcinoma pT3bN0R0 under a watchful waiting strategy for 6 months presented to the Medical Oncology appointment with two axillary and cervical adenopathies.

DIAGNOSIS

Cervicothoracoabdominal computed tomography confirmed the presence of two large necrotic lymphadenopathies in the cervical and axillary lymphatic chains, and bone scintigraphy revealed dorsal (D11) and lumbar (L5) metastatic lesions. Ultrasonography-guided biopsy of the axillary nodule revealed the presence of metastatic tissue of primary urothelial origin.

INTERVENTIONS

The patient was initiated on a palliative chemotherapy regimen of carboplatin area under the curve 5 plus gemcitabine (1000 mg/m2). During the first cycle of chemotherapy, acute kidney failure akin 2 developed due to nonobstructive toxic acute tubular necrosis with progressive deterioration of kidney function. Therefore, palliative chemotherapy with carboplatin plus gemcitabine was changed to 200 mg of pembrolizumab every 21 days.

OUTCOMES

Overal survival of 57 months with an immune complete response according to the immune Response Evaluation Criteria in Solid Tumours criteria and an excellent quality of life.

CONCLUSION

This case illustrates that second-line therapy with ICIs (pembrolizumab or atezolizumab) has favourable results in achieving an immune complete response after intolerance to cisplatin-based regimens. ICIs provide durable responses that improve overall survival and quality of life.

Intravesical VAX014 Synergizes with PD-L1 Blockade to Enhance Local and Systemic Control of Bladder Cancer

Emerging clinical evidence indicates that the combination of local administration of immunotherapy with systemic immune checkpoint blockade targeting the PD-1/PD-L1 pathway improves response rates in select solid tumor indications; however, limited clinical experience with this approach exists in advanced bladder cancer patients. VAX014 is a novel bacterial minicell-based, integrin-targeted oncolytic agent undergoing clinical investigation for intravesical (IVE) treatment of non-muscle invasive bladder cancer. Here, we demonstrated that the antitumor activity of VAX014 following IVE administration was dependent upon CD4+ and CD8+ T cells in two syngeneic orthotopic bladder tumor models (MB49 and MBT-2). PD-L1 upregulation was found to be an acquired immune-resistance mechanism in the MB49 model, and the combination of VAX014 with systemic PD-L1 blockade resulted in a significant improvement in bladder tumor clearance rates and development of protective antitumor immunologic memory. Combination treatment also led to enhanced systemic antitumor immune responses capable of clearing distal intradermal tumors and controlling pulmonary metastasis. Distal tumors actively responding to combination therapy demonstrated a phenotypic shift from Treg to Th1 in intratumoral CD4+ T cells, which was accompanied by a higher percentage of activated CD8+ T cells and higher IFNγ. Finally, VAX014's target integrins α3β1 and α5β1 were overexpressed in tumor biopsies from advanced stage bladder cancer patients, as well as in both the MB49 and MBT-2 orthotopic mouse models of bladder cancer. These collective findings provide rationale for clinical investigation of VAX014 and systemic PD-1/PD-L1 blockade in advanced stage bladder cancer.

piRNAs and PIWI Proteins as Diagnostic and Prognostic Markers of Genitourinary Cancers

piRNAs (PIWI-interacting RNAs) are small non-coding RNAs capable of regulation of transposon and gene expression. piRNAs utilise multiple mechanisms to affect gene expression, which makes them potentially more powerful regulators than microRNAs. The mechanisms by which piRNAs regulate transposon and gene expression include DNA methylation, histone modifications, and mRNA degradation. Genitourinary cancers (GC) are a large group of neoplasms that differ by their incidence, clinical course, biology, and prognosis for patients. Regardless of the GC type, metastatic disease remains a key therapeutic challenge, largely affecting patients’ survival rates. Recent studies indicate that piRNAs could serve as potentially useful biomarkers allowing for early cancer detection and therapeutic interventions at the stage of non-advanced tumour, improving patient’s outcomes. Furthermore, studies in prostate cancer show that piRNAs contribute to cancer progression by affecting key oncogenic pathways such as PI3K/AKT. Here, we discuss recent findings on biogenesis, mechanisms of action and the role of piRNAs and the associated PIWI proteins in GC. We also present tools that may be useful for studies on the functioning of piRNAs in cancers.

Payload Delivery: Engineering Immune Cells to Disrupt the Tumour Microenvironment

Although chimeric antigen receptor (CAR) T cells have shown impressive clinical success against haematological malignancies such as B cell lymphoma and acute lymphoblastic leukaemia, their efficacy against non-haematological solid malignancies has been largely disappointing. Solid tumours pose many additional challenges for CAR T cells that have severely blunted their potency, including homing to the sites of disease, survival and persistence within the adverse conditions of the tumour microenvironment, and above all, the highly immunosuppressive nature of the tumour milieu. Gene engineering approaches for generating immune cells capable of overcoming these hurdles remain an unmet therapeutic need and ongoing area of research. Recent advances have involved gene constructs for membrane-bound and/or secretable proteins that provide added effector cell function over and above the benefits of classical CAR-mediated cytotoxicity, rendering immune cells not only as direct cytotoxic effectors against tumours, but also as vessels for payload delivery capable of both modulating the tumour microenvironment and orchestrating innate and adaptive anti-tumour immunity. We discuss here the novel concept of engineered immune cells as vessels for payload delivery into the tumour microenvironment, how these cells are better adapted to overcome the challenges faced in a solid tumour, and importantly, the novel gene engineering approaches required to deliver these more complex polycistronic gene constructs.

Stromal LAG-3+ cells infiltration defines poor prognosis subtype muscle-invasive bladder cancer with immunoevasive contexture

BACKGROUND

Lymphocyte activation gene 3 (LAG-3) is a promising immune checkpoint therapeutic target being evaluated in clinical trials. We assessed the LAG-3⁺ cells distribution, its association with clinical outcomes and immune contexture and its role in the landscape of muscle-invasive bladder cancer (MIBC) treatment.

METHODS

141 patients with MIBC from Zhongshan Hospital were included for survival and adjuvant chemotherapy (ACT) benefit analyses. 32 fresh resected samples of MIBC were collected to detect CD8⁺ T cells functional state. The molecular classification analyses were based on 391 patients with MIBC from The Cancer Genome Atlas. Immunohistochemistry and flow cytometry were performed to characterize various immune cells infiltration.

RESULTS

In Kaplan-Meier analyses and Cox regression models, stromal LAG-3⁺ cells enrichment was consistently associated with inferior overall survival and disease-free survival, and indicated suboptimal responsiveness to ACT. Patents with high stromal LAG-3⁺ cells possessed increased protumor cells, immunosuppressive cytokines and immune checkpoint expression. The phenotypic analyses of CD8⁺ T cells correlated its dysfunctional state with LAG-3⁺ cells. Besides, LAG-3 mRNA level was linked to luminal and basal subtypes of MIBC. LAG-3-high tumors exhibited limited FGFR3 mutation and signaling signature, and displayed activated immunotherapeutic and EGFR-associated pathway.

CONCLUSIONS

Stromal LAG-3⁺ cells abundance indicated an immunoevasive contexture with dysfunctional CD8⁺ T cells, and represented an independent predictor for adverse survival outcome and ACT resistance in MIBC. LAG-3 expression could potentially be a novel biomarker for FGFR3-targeted and EGFR-targeted therapies and immunotherapy. The crucial role of LAG-3⁺ cells in the therapeutic landscape of MIBC needs further validation retrospectively and prospectively.

Immune Checkpoint Inhibitors-Related Cardiotoxicity

BACKGROUND

Immunotherapy is a significant breakthrough in cancer therapy in the last decade. Immunotherapy is better tolerated compared with chemotherapy. However, it does have side effects, and one of the rare and serious side effects of immunotherapy is cardiotoxicity. Cardiotoxicity has been described with other cancer-related treatments such as chemotherapy and targeted therapy. A high index of suspicion is required, and prompt management with immunosuppression needs to be instituted as soon as possible to prevent fatal outcomes.

AREAS OF UNCERTAINTY

Research is still ongoing to identify biomarkers that will help us to choose the patients, who will respond well to immunotherapy. Tumor-infiltrating lymphocytes, tumor PD-L1 expression, and tumor mutational burden explored as potential biomarkers. There are no predictive biomarkers to identify patients who are at higher risk of severe cardiotoxicity. Both cardiologists and oncologists should be aware of cardiac toxicity from immune checkpoint inhibitors.

CONCLUSION

All patients who are starting immune checkpoint inhibitors should undergo baseline cardiac risk factor assessment with referral to a cardiologist in a patient with multiple risk factors or previous history of cardiovascular disease. Cardiac immune-related adverse events are higher in patients taking combination therapy with anti-CTLA-4/anti-PD-1 agents compared with monotherapy. Patients with known cardiac comorbidities require a higher level of vigilance to monitor for cardiac toxicity because nonspecific symptoms can lead to rapid clinical deterioration and a higher rate of mortality when treated with checkpoint inhibitors.

How Assessment-Schedule Matching Limits Bias When Comparing Progression-Free Survival in Single-Arm Studies: An Application in Second-Line Urothelial Carcinoma Treatments

OBJECTIVES

Population-adjusted comparisons of progression-free survival (PFS) from single-arm trials of cancer treatments can be derived using matching-adjusted indirect comparisons (MAICs); however, results are still susceptible to bias, particularly if the trials had different tumor assessment schedules. This study aims to assess the effects of assessment-schedule matching (ASM) on the relative effectiveness on the PFS of avelumab versus approved comparator immunotherapies or chemotherapy after population matching in the second-line (2L) setting for metastatic urothelial carcinoma.

METHODS

The MAIC used patient-level data for avelumab from the JAVELIN Solid Tumor trial (NCT01772004). PFS was compared with published curves for other treatments to obtain population-adjusted hazard ratios (HRs). The MAIC was repeated after conducting ASM for differences in tumor assessment scheduled first at 6 weeks for avelumab and durvalumab and at 8 or 9 weeks for other treatments.

RESULTS

MAIC adjustment alone altered the HR estimates up to 23%, whereas MAIC plus ASM resulted in up to 32.7% reductions from naive comparisons. Even in cases in which MAIC had little effect, ASM brought an additional change of 11.1% to 15.4%. Overall, the HR range of avelumab versus other treatments changed from 0.83 to 1.25 for naive comparisons to 0.76 to 0.99 after ASM plus MAIC, numerically favoring avelumab.

CONCLUSIONS

Small variations in assessment schedules can introduce bias in unanchored indirect treatment comparisons of interval-censored time-to-event outcomes. In this study, adjusted PFS was comparable across second-line urothelial carcinoma treatment options, numerically favoring avelumab versus immunotherapies and chemotherapy agents. Correcting this bias is especially important when HRs are applied in cost-effectiveness models to transition patients between states.

Detection of PD-L1 in the urine of patients with urothelial carcinoma of the bladder

There are currently five programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) inhibitors approved for the treatment of locally advanced or metastatic urothelial carcinoma (UC) of the bladder. For platinum-ineligible patients, testing of tumor specimens for PD-L1 expression is required. However, scoring of PD-L1 immunohistochemistry is complex due to different antibodies used, the requirement to score expression in different cellular compartments and intratumoral heterogeneity. It can also be difficult to obtain and test longitudinal tumor samples, which would be desirable to monitor treatment responses and tumor evolution under treatment-induced selective pressure. In the present proof-of concept study, we provide evidence that PD-L1 can be detected in the urine of patients with non-muscle invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC). Urine PD-L1 levels were significantly higher in NMIBC and MIBC patients when compared to patients with various non-malignant urological diseases. Further prospective and independent studies are required to assess the value of PD-L1 in the urine as a novel biomarker with potential for the early detection, prediction and therapeutic monitoring of patients with UC of the bladder.

Epigenomic and Metabolomic Integration Reveals Dynamic Metabolic Regulation in Bladder Cancer

Bladder cancer (BC) represents a clinical, social, and economic challenge due to tumor-intrinsic characteristics, limitations of diagnostic techniques and a lack of personalized treatments. In the last decade, the use of liquid biopsy has grown as a non-invasive approach to characterize tumors. Moreover, the emergence of omics has increased our knowledge of cancer biology and identified critical BC biomarkers. The rewiring between epigenetics and metabolism has been closely linked to tumor phenotype. Chromatin remodelers interact with each other to control gene silencing in BC, but also with stress-inducible factors or oncogenic signaling cascades to regulate metabolic reprogramming towards glycolysis, the pentose phosphate pathway, and lipogenesis. Concurrently, one-carbon metabolism supplies methyl groups to histone and DNA methyltransferases, leading to the hypermethylation and silencing of suppressor genes in BC. Conversely, α-KG and acetyl-CoA enhance the activity of histone demethylases and acetyl transferases, increasing gene expression, while succinate and fumarate have an inhibitory role. This review is the first to analyze the interplay between epigenome, metabolome and cell signaling pathways in BC, and shows how their regulation contributes to tumor development and progression. Moreover, it summarizes non-invasive biomarkers that could be applied in clinical practice to improve diagnosis, monitoring, prognosis and the therapeutic options in BC.

Prospective bladder cancer infrastructure for experimental and observational research on bladder cancer: study protocol for the 'trials within cohorts' study ProBCI

INTRODUCTION

A better understanding of the molecular profile of bladder tumours, the identification of novel therapeutic targets, and introduction of new drugs and has renewed research interest in the field of bladder cancer. We describe the design and setup of a Dutch Prospective Bladder Cancer Infrastructure (ProBCI) as a means to stimulate and accelerate clinically meaningful experimental and observational research.

METHODS AND ANALYSIS

ProBCI entails an open cohort of patients with bladder cancer in which the trials within cohorts (TwiCs) design can be embedded. Physicians in participating hospitals prospectively recruit invasive (≥T1) patients with bladder cancer on primary diagnosis for inclusion into the study. Extensive clinical data are collected and updated every 4 months, along with patient-reported outcomes and biomaterials. Informed consent includes participation in TwiCs studies and renewed contact for future studies. Consent for participation in questionnaires and molecular analyses that may yield incidental findings is optional.

ETHICS AND DISSEMINATION

The Dutch ProBCI is a unique effort to construct a nation-wide cohort of patients with bladder cancer including clinical data, patient-reported outcomes and biomaterial, to facilitate observational and experimental research. Data and materials are available for other research groups on request through www.probci.nl. Ethics approval was obtained from METC Utrecht (reference: NL70207.041.19).

TRIAL REGISTRATION NUMBER

NCT04503577.

Imaging and Management of Bladder Cancer

Simple Summary

Bladder cancer is a complex disease, the sixth most common cancer, and one of the most expensive cancers to treat. In the last few decades, there has been a significant decrease in the bladder cancer-related mortality rate, potentially related to decreased smoking prevalence, improvements in diagnosing bladder cancer, and advances in treatment. Those advances in diagnostic tools and therapies and greater understanding of the disease are helping to evolve how bladder cancer is managed. The purpose of this article is to provide a review of bladder cancer pathology, diagnosis, staging, radiologic imaging, and management, and highlight recent developments and research.

Abstract

Methods: Keyword searches of Medline, PubMed, and the Cochrane Library for manuscripts published in English, and searches of references cited in selected articles to identify additional relevant papers. Abstracts sponsored by various societies including the American Urological Association (AUA), European Association of Urology (EAU), and European Society for Medical Oncology (ESMO) were also searched. Background: Bladder cancer is the sixth most common cancer in the United States, and one of the most expensive in terms of cancer care. The overwhelming majority are urothelial carcinomas, more often non-muscle invasive rather than muscle-invasive. Bladder cancer is usually diagnosed after work up for hematuria. While the workup for gross hematuria remains CT urography and cystoscopy, the workup for microscopic hematuria was recently updated in 2020 by the American Urologic Association with a more risk-based approach. Bladder cancer is confirmed and staged by transurethral resection of bladder tumor. One of the main goals in staging is determining the presence or absence of muscle invasion by tumor which has wide implications in regards to management and prognosis. CT urography is the main imaging technique in the workup of bladder cancer. There is growing interest in advanced imaging techniques such as multiparametric MRI for local staging, as well as standardized imaging and reporting system with the recently created Vesicle Imaging Reporting and Data System (VI-RADS). Therapies for bladder cancer are rapidly evolving with immune checkpoint inhibitors, particularly programmed death ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) inhibitors, as well as another class of immunotherapy called an antibody-drug conjugate which consists of a cytotoxic drug conjugated to monoclonal antibodies against a specific target. Conclusion: Bladder cancer is a complex disease, and its management is evolving. Advances in therapy, understanding of the disease, and advanced imaging have ushered in a period of rapid change in the care of bladder cancer patients.

PD-L2 Is Constitutively Expressed in Normal and Malignant Urothelium

The use of immune checkpoint blockade, in particular PD-1 and PD-L1 inhibitors, is now commonplace in many clinical settings including the treatment of muscle-invasive bladder cancer (MIBC). Notwithstanding, little information exists regarding the expression of the alternative PD-1 ligand, PD-L2 in urothelial bladder cancer (UBC). We therefore set out to characterise the expression of PD-L2 in comparison to PD-L1. Firstly, we assessed PD-L2 expression by immunohistochemistry and found widespread expression of PD-L2 in UBC, albeit with reduced expression in MIBC. We further investigated these findings using RNA-seq data from a cohort of 575 patients demonstrating that PDCD1LG2 (PD-L2) is widely expressed in UBC and correlated with CD274 (PD-L1). However, in contrast to our immunohistochemistry findings, expression was significantly increased in advanced disease. We have also provided detailed evidence of constitutive PD-L2 expression in normal urothelium and propose a mechanism by which PD-L2 is cleaved from the cell surface in MIBC. These data provide a comprehensive assessment of PD-L2 in UBC, showing PD-L2 is abundant in UBC and, importantly, constitutively present in normal urothelium. These data have implications for future development of immune checkpoint blockade, and also the understanding of the function of the immune system in the normal urinary bladder.

Management of Clinically Regional Node-Positive Urothelial Carcinoma of the Bladder

PURPOSE OF REVIEW

Clinically regional node-positive (cN+) urothelial carcinoma of the bladder requires a multi-modal management approach amidst growing recognition that it represents a spectrum of disease. Herein, we review the contemporary evidence for the natural history, evaluation, and management of clinically regional node-positive urothelial carcinoma of the bladder, highlighting recent changes in lymph node staging.

RECENT FINDINGS

Despite advances in techniques, cross-sectional imaging remains relatively insensitive for the detection of lymph node metastases. Recent changes to nodal staging that distinguish between cN1, cN2-3, and non-regional lymph node metastases reflect an increasing understanding that node-positive disease is heterogeneous and its management must be individualized according to nodal staging. Systemic therapy remains the initial management strategy, either alone or in conjunction with radiotherapy, with choice and sequencing of agents extrapolated from studies of metastatic disease. Consolidative radical cystectomy is an option for patients with disease response to upfront systemic therapy, and several series demonstrate a subset of patients with favorable oncologic outcomes. The comparative effectiveness of radiotherapy and radical cystectomy as local therapy remains an important evidence gap. Future studies that identify predictive biomarkers will help inform optimal choice of systemic therapy. The management of clinically regional node-positive disease requires a multimodal approach comprising both systemic and local therapy, tailored to the patient and to disease response. While choice of systemic therapy will be informed by ongoing studies in patients with metastatic disease, including the elucidation of predictive biomarkers, the comparative effectiveness of local therapies remains an important evidence gap.

Epidemiology and treatment patterns for locally advanced or metastatic urothelial carcinoma: a systematic literature review and gap analysis

BACKGROUND: Several immuno-oncology (IO) agents targeting programmed death-1 or programmed death-ligand 1 (PD-1/L1) are approved second-line therapy options for patients with locally advanced or metastatic urothelial carcinoma (la/mUC) previously treated with platinum-based chemotherapy or first-line options in patients ineligible for cisplatin whose tumors express PD-L1 or for any platinum-based chemotherapy regardless of PD-L1 expression levels. However, literature on the epidemiology of la/mUC is limited, and real-world treatment patterns are not well established, especially with respect to therapies used following IO. OBJECTIVES: To (a) report the epidemiology of urothelial carcinoma (UC) and la/mUC; (b) identify and summarize the published literature on la/mUC treatment patterns, including IO and post-IO treatment; and (c) identify evidence gaps. METHODS: A systematic literature review was conducted using Cochrane dual-reviewer methodology and the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Literature databases and selected congress abstracts (2017-2018) were searched for retrospective studies published January 2013-August 2018 in English reporting epidemiological and treatment data (all lines of therapy) for adult patients with la/mUC. RESULTS: Among 6,584 database references and 1,832 congress abstracts screened, 45 publications (29 manuscripts, 1 poster, 15 abstracts; reporting 37 unique studies) were retained. All studies related to treatment patterns, and the majority were from the United States (n = 17), Japan (n = 8), and the United Kingdom (n = 5). Epidemiological data were not identified among the searches thus online registries were leveraged. Among the identified publications, 21 (20 unique) reported on cisplatin versus non-cisplatin regimens, 14 (8 unique) on IO, and 9 (7 unique) on vinflunine. Cisplatin use varied both within and among countries (ranging from 18.4% in 1 U.S. study to 87.9% in 1 Japanese study). The use of IO was higher in later lines of therapy, ranging from 1.4% to 7.9% as first-line therapy to 57.8% as second-line and 64.4% as third-line therapy. Among studies reporting IO discontinuation rates, 41.4%-71% of patients were reported to discontinue IO across the studies, and the median time to discontinuation ranged from 2.7 to 5.8 months. Only 25%-35.5% of patients received subsequent therapy following IO discontinuation; post-IO treatments varied widely. CONCLUSIONS: Additional published data on the country-specific epidemiology of UC and la/mUC are needed, including rates of progression from early-stage disease to la/mUC. There was large variation in treatment rates, particularly cisplatin use, within and across countries. The few published real-world IO studies reported high levels of discontinuation with only a small percentage of patients receiving subsequent therapy. As IO therapies continue to be granted regulatory approval in countries outside the United States and novel therapies gain approval in the post-IO setting, the treatment paradigm for patients with la/mUC is shifting, and future studies with more recent data will be required. DISCLOSURES: This study was funded by Astellas/Seagen. Hepp is an employee of and owns stock in Seagen. Shah was a contractor for Astellas Pharma at the time of the study and owns stock in Pfizer. Smoyer is an employee and shareholder of Envision Pharma Group, paid consultants to Seagen. Vadagam was an employee of Envision Pharma Group, paid consultants to Seagen, at the time of the study. Parts of these data have been presented at the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) 2019 Annual Meeting; May 18-22, 2019; New Orleans, LA.

The Functional Crosstalk between Myeloid-Derived Suppressor Cells and Regulatory T Cells within the Immunosuppressive Tumor Microenvironment

Simple Summary

Immunotherapy improved the therapeutic landscape for patients with advanced cancer diseases. However, many patients do not benefit from immunotherapy. The bidirectional crosstalk between myeloid-derived suppressor cells (MDSC) and regulatory T cells (Treg) contributes to immune evasion, limiting the success of immunotherapy by checkpoint inhibitors. This review aims to outline the current knowledge of the role and the immunosuppressive properties of MDSC and Treg within the tumor microenvironment (TME). Furthermore, we will discuss the importance of the functional crosstalk between MDSC and Treg for immunosuppression, issuing particularly the role of cell adhesion molecules. Lastly, we will depict the impact of this interaction for cancer research and discuss several strategies aimed to target these pathways for tumor therapy.

Abstract

Immune checkpoint inhibitors (ICI) have led to profound and durable tumor regression in some patients with metastatic cancer diseases. However, many patients still do not derive benefit from immunotherapy. Here, the accumulation of immunosuppressive cell populations within the tumor microenvironment (TME), such as myeloid-derived suppressor cells (MDSC), tumor-associated macrophages (TAM), and regulatory T cells (Treg), contributes to the development of immune resistance. MDSC and Treg expand systematically in tumor patients and inhibit T cell activation and T effector cell function. Numerous studies have shown that the immunosuppressive mechanisms exerted by those inhibitory cell populations comprise soluble immunomodulatory mediators and receptor interactions. The latter are also required for the crosstalk of MDSC and Treg, raising questions about the relevance of cell–cell contacts for the establishment of their inhibitory properties. This review aims to outline the current knowledge on the crosstalk between these two cell populations, issuing particularly the potential role of cell adhesion molecules. In this regard, we further discuss the relevance of β2 integrins, which are essential for the differentiation and function of leukocytes as well as for MDSC–Treg interaction. Lastly, we aim to describe the impact of such bidirectional crosstalk for basic and applied cancer research and discuss how the targeting of these pathways might pave the way for future approaches in immunotherapy.

Aristolochic acid and its effect on different cancers in uro-oncology

PURPOSE OF REVIEW

To acquaint urologists with aristolochic acid nephropathy, an iatrogenic disease that poses a distinct threat to global public health. In China alone, 100 million people may currently be at risk. We illustrate the power of molecular epidemiology in establishing the cause of this disease.

RECENT FINDINGS

Molecular epidemiologic approaches and novel mechanistic information established a causative linkage between exposure to aristolochic acid and urothelial carcinomas of the bladder and upper urinary tract. Noninvasive tests are available that detect urothelial cancers through the genetic analysis of urinary DNA. Combined with cytology, some of these tests can detect 95% of patients at risk of developing bladder and/or upper urothelial tract cancer. Robust biomarkers, including DNA-adduct and mutational signature analysis, unequivocally identify aristolochic acid-induced tumours. The high mutational load associated with aristolochic acid-induced tumours renders them candidates for immune-checkpoint therapy.

SUMMARY

Guided by recent developments that facilitate early detection of urothelial cancers, the morbidity and mortality associated with aristolochic acid-induced bladder and upper tract urothelial carcinomas may be substantially reduced. The molecular epidemiology tools that define aristolochic acid-induced tumours may be applicable to other studies assessing potential environmental carcinogens.

Utilization of systemic treatment for metastatic bladder cancer in everyday practice: Results of a nation-wide population-based cohort study

BACKGROUND

With the introduction of new therapeutic options, the landscape of metastatic bladder cancer (mBC) management is shifting. We describe current clinical practice and outcomes of mBC patients as a benchmark for translation of developments into clinical practice in the near future.

PATIENTS AND METHODS

Nation-wide population-based cohort study including all patients diagnosed with synchronous metastatic bladder cancer in the Netherlands in 2016-2017, identified through the Netherlands Cancer Registry (NCR). Clinical data on patient and disease characteristics, treatments and survival from the NCR were supplemented with specific information from electronic health records and descriptively analyzed. This study was part of the Prospective Bladder Cancer Infrastructure.

RESULTS

Synchronous metastatic bladder cancer was diagnosed in 636 patients in the Netherlands in 2016 and 2017. 35% (221 patients) received systemic treatment, of whom 88 received multiple treatment lines. Most common first-line regimen was carboplatin-based chemotherapy (49%), followed by cisplatin-based chemotherapy (41%) and immunotherapy (8%). Factors associated with systemic treatment were: young age, <2 comorbidities, adequate renal function and performance-status (WHO-0-1/Karnofsky-80-100), urothelial carcinoma and lymph node only metastases. Median overall survival was 4.4 months for the total cohort, and 12.3, 12.9 and 11.1 months for patients treated with first-line immunotherapy, cisplatin-based and carboplatin-based chemotherapy, respectively.

CONCLUSIONS

Many mBC patients received no systemic treatment or received carboplatin-based chemotherapy, partly because of cisplatin-ineligibility. Observed survival corresponded relatively well with rates reported from trials among chemotherapy-treated patients. These data can serve as a benchmark for future studies evaluating the application of immunotherapy outside a trial setting.

Identification of Sex Differences in Tumor-Specific T Cell Infiltration in Bladder Tumor-Bearing Mice Treated with BCG Immunotherapy

BACKGROUND: Bladder cancer is the fourth most common cancer for men. However, women are often diagnosed with later stage disease and have poorer outcomes. Whether immune-based sex differences contribute to this discrepancy is unclear. In addition, models to investigate tumor-specific immunity in bladder cancer, in the context of tumor development or response to therapy, are lacking. OBJECTIVE: To address this specific unmet need, we incorporated a commonly used model antigen, ovalbumin, into two well-established models of bladder cancer; the orthotopic MB49 cell line model and the carcinogenic BBN bladder cancer model. METHOD: We tested the utility of these models to investigate tumor-specific immunity in the context of immunotherapy in both sexes. RESULTS: We found that BCG vaccination, prior to weekly BCG instillation does not impart an immune-specific benefit to tumor-bearing mice in the context of multiple BCG instillations. Furthermore, tumors developed in the testes in male mice, precluding the use of the MB49 model to directly investigate sex-based immune differences. In the BBN model, we observed that more tumor antigen-specific CD8+ T cells infiltrated male bladders compared to female bladders in the context of BCG immunotherapy whereas regulatory T cells had higher levels of the exhaustion marker PD-1 in female mice. CONCLUSIONS: We propose our modified BBN model will contribute to our understanding of how tumor-specific immunity arises in bladder cancer. Additionally, the BBN bladder cancer model may help to uncover sex differences in tumor-specific immunity, which would provide valuable information for the development of new treatments or combination therapies for bladder cancer in women and men.

Update on bladder cancer molecular subtypes

In 2014, there was a burst of studies on the molecular subtypes of bladder cancer in the published literature that was made possible by the advances in high-throughput technologies. Based on gene expression profiling, the major molecular classification subdivisions were basal and luminal subtypes, which resembled to those observed in breast cancers. These basal and luminal subtypes were further subdivided by TCGA into squamous, infiltrated, luminal-papillary, luminal/genomically unstable (GU), and neuronal/small cell carcinoma (SCC) subtypes. Recently, an international subtypes consensus project further expanded on the TCGA subtypes by defining a consensus molecular classification (CMC). A multidisciplinary team of experts generated CMC to overcome the difficulties of clinical applications due to several published bladder cancer molecular classifications with various nomenclatures and molecular features. It included six molecular subtypes with the addition of one more luminal subtype (luminal nonspecified) compared to the TCGA subtype classification. The initial research efforts have focused on the characterization of each subtype at the molecular and histopathologic levels, but more recent studies have examined their significance in terms of clinical utility, i.e., biomarkers that inform prognostication and/or to predict therapeutic responses to be tested in future clinical trials. This review provides an overview of recent investigations into the relationship between molecular subtypes and the clinical management of patients with bladder cancer.

Maintenance avelumab for metastatic urothelial cancer: a new standard of care

The Javelin Bladder 100 trial was the first trial to establish the role of switch maintenance therapy in patients with metastatic urothelial cancer using avelumab, a PD-L1 inhibitor, for patients who achieve complete response, partial response, or stable disease to standard chemotherapy of 4-6 cycles with gemcitabine and cisplatin or carboplatin. Improvement in parameters of overall survival in both the overall population and the PD-L1 positive population was seen and has led to the US FDA approval of avelumab as maintenance therapy for metastatic urothelial cancer. This manuscript further discusses the highlights of the study, patient population, and considerations regarding choice of therapy for maintenance avelumab.

Targeted Molecular Therapeutics for Bladder Cancer-A New Option beyond the Mixed Fortunes of Immune Checkpoint Inhibitors?

The fact that there are now five immune checkpoint inhibitor (ICI) monoclonal antibodies approved since 2016 that target programmed cell death protein 1 or programmed death ligand-1 for the treatment of metastatic and refractory bladder cancer is an outstanding achievement. Although patients can display pronounced responses that extend survival when treated with ICIs, the main benefit of these drugs compared to traditional chemotherapy is that they are better tolerated and result in reduced adverse events (AEs). Unfortunately, response rates to ICI treatment are relatively low and, these drugs are expensive and have a high economic burden. As a result, their clinical efficacy/cost-value relationship is debated. Long sought after targeted molecular therapeutics have now emerged and are boasting impressive response rates in heavily pre-treated, including ICI treated, patients with metastatic bladder cancer. The antibody-drug conjugates (ADCs) enfortumab vedotin (EV) and sacituzumab govitecan (SG) have demonstrated the ability to provide objective response rates (ORRs) of 44% and 31% in patients with bladder tumor cells that express Nectin-4 and Trop-2, respectively. As a result, EV was approved by the U.S. Food and Drug Administration for the treatment of patients with advanced or metastatic bladder cancer who have previously received ICI and platinum-containing chemotherapy. SG has been granted fast track designation. The small molecule Erdafitinib was recently approved for the treatment of patients with advanced or metastatic bladder cancer with genetic alterations in fibroblast growth factor receptors that have previously been treated with a platinum-containing chemotherapy. Erdafitinib achieved an ORR of 40% in patients including a proportion who had previously received ICI therapy. In addition, these targeted drugs are sufficiently tolerated or AEs can be appropriately managed. Hence, the early performance in clinical effectiveness of these targeted drugs are substantially increased relative to ICIs. In this article, the most up to date follow-ups on treatment efficacy and AEs of the ICIs and targeted therapeutics are described. In addition, drug price and cost-effectiveness are described. For best overall value taking into account clinical effectiveness, price and cost-effectiveness, results favor avelumab and atezolizumab for ICIs. Although therapeutically promising, it is too early to determine if the described targeted therapeutics provide the best overall value as cost-effectiveness analyses have yet to be performed and long-term follow-ups are needed. Nonetheless, with the arrival of targeted molecular therapeutics and their increased effectiveness relative to ICIs, creates a potential novel paradigm based on 'targeting' for affecting clinical practice for metastatic bladder cancer treatment.

Clinical Pharmacokinetics and Pharmacodynamics of Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) have demonstrated significant clinical impact in improving overall survival of several malignancies associated with poor outcomes; however, only 20–40% of patients will show long-lasting survival. Further clarification of factors related to treatment response can support improvements in clinical outcome and guide the development of novel immune checkpoint therapies. In this article, we have provided an overview of the pharmacokinetic (PK) aspects related to current ICIs, which include target-mediated drug disposition and time-varying drug clearance. In response to the variation in treatment exposure of ICIs and the significant healthcare costs associated with these agents, arguments for both dose individualization and generalization are provided. We address important issues related to the efficacy and safety, the pharmacodynamics (PD), of ICIs, including exposure–response relationships related to clinical outcome. The unique PK and PD aspects of ICIs give rise to issues of confounding and suboptimal surrogate endpoints that complicate interpretation of exposure–response analysis. Biomarkers to identify patients benefiting from treatment with ICIs have been brought forward. However, validated biomarkers to monitor treatment response are currently lacking.

Monoclonal Antibody Against ROR1 Induces Apoptosis in Human Bladder Carcinoma Cells

BACKGROUND

Receptor tyrosine kinase-like Orphan Receptor 1 (ROR1) is one of the promising cell surface antigens for targeting cancer cells. The aim of this study was to evaluate ROR1 cell surface expression in bladder cancer cells using a murine anti-ROR1 monoclonal antibody (mAb) called 5F1-B10 as well as investigate its potential in apoptosis induction.

METHODS

Expression of ROR1 in two human bladder cell lines, 5637 and EJ138, as well as a non-cancerous human cell line, Human Fetal Foreskin Fibroblast (HFFF), was examined by flow cytometry and immunocytochemistry. Immunohistochemical staining of cancer and normal bladder tissues was also performed.

RESULTS

The flow cytometry results showed that 5F1-B10 mAb could recognize ROR1 molecules in 86.1% and 45.6% of 5637 and EJ138 cells, respectively. The expression level of ROR1 was 5.49% in HFFF cells. The immunocytochemistry and immunohistochemistry staining results also confirmed the presence of ROR1 on the surface of both bladder cancer cells and tissues, respectively. The obtained data from apoptosis assay demonstrated that 5F1-B10 mAb could induce apoptosis in both 5637 and EJ138 cell lines.

CONCLUSION

Taken together, our finding indicates the role of ROR1 in bladder cancer cell survival and suggests this receptor might be a promising target for developing novel therapeutic agents against bladder carcinoma.

Trial watch: IDO inhibitors in cancer therapy

Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first, rate-limiting step of the so-called “kynurenine pathway”, which converts the essential amino acid L-tryptophan (Trp) into the immunosuppressive metabolite L-kynurenine (Kyn). While expressed constitutively by some tissues, IDO1 can also be induced in specific subsets of antigen-presenting cells that ultimately favor the establishment of immune tolerance to tumor antigens. At least in part, the immunomodulatory functions of IDO1 can be explained by depletion of Trp and accumulation of Kyn and its derivatives. In animal tumor models, genetic or pharmacological IDO1 inhibition can cause the (re)activation of anticancer immune responses. Similarly, neoplasms expressing high levels of IDO1 may elude anticancer immunosurveillance. Therefore, IDO1 inhibitors represent promising therapeutic candidates for cancer therapy, and some of them have already entered clinical evaluation. Here, we summarize preclinical and clinical studies testing IDO1-targeting interventions for oncologic indications.

Metastatic retro-crural lymph nodes from transitional cell carcinoma of bladder successfully treated with single session cryoablation

Bladder cancer (BC) is a relatively common tumor, with a male preponderance. High-grade muscle invasive bladder cancer (MIBC) has a very high incidence of pelvic lymph node metastasis at presentation. Involvement of the retro-crural lymph nodes, although has been described in other pelvic tumors, is very uncommon for BC. Cryoablation in the retro-crural region is extremely challenging due to the proximity to the critical structures like inferior venacava and aorta and has not been extensively reported. We describe a 56-year old male patient with MIBC who underwent extensive treatments including radical cystoprostatectomy, chemoradiation and immunotherapy, ultimately with localized disease in the retro-crural region. Single session cryoablation of these lymph nodes was performed with a curative intent yielding a positive response that has persisted for more than 2 years.

Common phenotypic dynamics of tumor-infiltrating lymphocytes across different histologies upon checkpoint inhibition: impact on clinical outcome

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized the cancer therapeutic landscape and our perception of interactions between the immune system and tumor cells. Despite remarkable progress, disease relapse and primary resistance are not uncommon. Understanding the biological processes that tumor-infiltrating lymphocytes (TILs) undergo during ICI, how this affects the tumor microenvironment (TME) and, ultimately, clinical outcome is, therefore, necessary to further improve treatment efficacy.

AIM

In the current study, we sought to characterize TILs from patients with metastatic solid tumors undergoing ICI correlating flowcytometric findings with clinical outcome.

METHODS

In total, 20 patients with 10 different metastatic solid tumors treated with ICIs targeting programmed-cell death-1 (PD-1)/PD-L1 axis were included in this study. The phenotype of T cells deriving from biopsies obtained prior to treatment initiation and on-treatment was investigaded. Analyses were focused on T cells' degree of differentiation and activity and how they correlate with transcriptomic changes in the TME.

RESULTS

Data indicate that patients benefitting from ICIs accumulate CD8+central memory T cells. TILs developed an effector-like phenotype over time, which was also associated with a cytolytic gene signature. In terms of modulation of T-cell responses, we observed that high expression of checkpoint molecules pre-treatment (i.e., PD-1, lymphocyte activation gene-3 [LAG-3], B and T-lymphocyte attenuator [BTLA] and T-cell immunoglobulin and mucin domain containing-3 [TIM-3]) was associated with similar gene signature and correlated to treatment benefit. Increasing expression of LAG-3 and BTLA in the CD8 compartment and their co-expression with PD-1 during treatment were, however, a common feature for patients who failed to respond to ICIs.

CONCLUSIONS

Besides identifying immune profiles suggestive of response to ICI, our results provide a more nuanced picture regarding expression of checkpoint molecules that goes beyond T-cell anergy.

An improved mouse orthotopic bladder cancer model exhibiting progression and treatment response characteristics of human recurrent bladder cancer

Nonmuscle-invasive (superficial) bladder cancer is generally treated via surgical removal, followed by adjuvant therapy (bacillus Calmette-Guerin). However, bladder cancer can often recur, and in a substantial number of recurrent cases, the cancer progresses and metastasizes. Furthermore, residual microtumors following excision may lead to an increased risk of recurrence. An in vivo model mimicking the pattern of urinary bladder microtumor regrowth may provide an effective experimental system for improving postsurgical treatment outcomes. A mouse bladder cancer model established using orthotopic transplant of UM-UC-3 human urinary bladder carcinoma cells has been established, however, to the best of our knowledge, no report has investigated sequential histological changes, including early-phase changes and treatment responses in bladder cancer. In the present study, the efficiency of the model was optimized and the sequential changes were examined using histopathology and in situ imaging. The therapeutic effects of cisplatin (CDDP) and gemcitabine (GEM) were also examined, which are drugs that are often used for follow-up chemotherapy. Tumor-seeding efficiency reached 90-100%, with muscle layer and bladder lumen invasion occurring in ~21 days, using the following modifications: i) Shallow catheter insertion to mitigate bladder wall damage; ii) bladder pretreatment using prewarmed trypsin, followed by light urethral clamping and body temperature maintenance for more efficient removal of transitional epithelium; and iii) seeding with UM-UC-3 cells (rather than HT1376, 5637 or T24 tumor cells) in a medium supplemented with Matrigel. Transplant with UM-UC-3 cells resulted in isolated microlesions that progressed into tumors, invading the bladder lumen and muscle layer to the serosal surface. Tumor growth was markedly reduced by weekly intravenous injections of CDDP and partially suppressed by GEM. Therefore, this model is reliable, and pathological progression and treatment responses recapitulate the features of recurrent human bladder cancer.

9-ING-41, a small molecule inhibitor of GSK-3beta, potentiates the effects of anticancer therapeutics in bladder cancer

Glycogen synthase kinase-3 beta (GSK-3β), a serine/threonine kinase, has been identified as a potential therapeutic target in human bladder cancer. In the present study, we investigated the antitumor effect of a small molecule GSK-3β inhibitor, 9-ING-41, currently in clinical studies in patients with advanced cancer, in bladder cancer cell lines. We found that treatment with 9-ING-41 leads to cell cycle arrest, autophagy and apoptosis in bladder cancer cells. The autophagy inhibitor chloroquine potentiated the antitumor effects of 9-ING-41 when tested in combination studies. Our findings also demonstrate that 9-ING-41 enhanced the growth inhibitory effects of gemcitabine or cisplatin when used in combination in bladder cancer cells. Finally, we found that 9-ING-41 sensitized bladder cancer cells to the cytotoxic effects of human immune effector cells. Our results provide a rationale for the inclusion of patients with advanced bladder cancer in clinical studies of 9-ING-41.

A genetically defined disease model reveals that urothelial cells can initiate divergent bladder cancer phenotypes

Small cell carcinoma of the bladder (SCCB) is a lethal variant of bladder cancer with no effective treatment. A lack of available preclinical models and clinical cohorts impedes our understanding of its molecular pathogenesis. In this study, we provided a tumor model as functional evidence showing that SCCB and other bladder cancer phenotypes can be derived from normal human urothelial cells. We further demonstrated that SCCB has a distinct transcriptome and identified SCCB-associated cell surface proteins (CSPs) that can be further evaluated as potential therapeutic targets. We show that our model shares CSP profile with clinical SCCB samples. Our findings create a foundation to understand the molecular underpinnings of SCCB and provide tools for developing therapeutic strategies.

Small cell carcinoma of the bladder (SCCB) is a rare and lethal phenotype of bladder cancer. The pathogenesis and molecular features are unknown. Here, we established a genetically engineered SCCB model and a cohort of patient SCCB and urothelial carcinoma samples to characterize molecular similarities and differences between bladder cancer phenotypes. We demonstrate that SCCB shares a urothelial origin with other bladder cancer phenotypes by showing that urothelial cells driven by a set of defined oncogenic factors give rise to a mixture of tumor phenotypes, including small cell carcinoma, urothelial carcinoma, and squamous cell carcinoma. Tumor-derived single-cell clones also give rise to both SCCB and urothelial carcinoma in xenografts. Despite this shared urothelial origin, clinical SCCB samples have a distinct transcriptional profile and a unique transcriptional regulatory network. Using the transcriptional profile from our cohort, we identified cell surface proteins (CSPs) associated with the SCCB phenotype. We found that the majority of SCCB samples have PD-L1 expression in both tumor cells and tumor-infiltrating lymphocytes, suggesting that immune checkpoint inhibitors could be a treatment option for SCCB. We further demonstrate that our genetically engineered tumor model is a representative tool for investigating CSPs in SCCB by showing that it shares a similar a CSP profile with clinical samples and expresses SCCB–up-regulated CSPs at both the mRNA and protein levels. Our findings reveal distinct molecular features of SCCB and provide a transcriptional dataset and a preclinical model for further investigating SCCB biology.

A phase Ib study of utomilumab (PF-05082566) in combination with mogamulizumab in patients with advanced solid tumors

BACKGROUND

Expressed on activated T and natural killer cells, 4-1BB/CD137 is a costimulatory receptor that signals a series of events resulting in cytokine secretion and enhanced effector function. Targeting 4-1BB/CD137 with agonist antibodies has been associated with tumor reduction and antitumor immunity. C-C chemokine receptor 4 (CCR4) is highly expressed in various solid tumor indications and associated with poor prognosis. This phase Ib, open-label study in patients with advanced solid tumors assessed the safety, efficacy, pharmacokinetics, and pharmacodynamics of utomilumab (PF-05082566), a human monoclonal antibody (mAb) agonist of the T-cell costimulatory receptor 4-1BB/CD137, in combination with mogamulizumab, a humanized mAb targeting CCR4 reported to deplete subsets of regulatory T cells (Tregs).

METHODS

Utomilumab 1.2-5 mg/kg or 100 mg flat dose every 4 weeks plus mogamulizumab 1 mg/kg (weekly in Cycle 1 followed by biweekly in Cycles ≥2) was administered intravenously to 24 adults with solid tumors. Blood was collected pre- and post-dose for assessment of drug pharmacokinetics, immunogenicity, and pharmacodynamic markers. Baseline tumor biopsies from a subset of patients were also analyzed for the presence of programmed cell death-ligand 1 (PD-L1), CD8, FoxP3, and 4-1BB/CD137. Radiologic tumor assessments were conducted at baseline and on treatment every 8 weeks.

RESULTS

No dose-limiting toxicities occurred and the maximum tolerated dose was determined to be at least 2.4 mg/kg per the time-to-event continual reassessment method. No serious adverse events related to either treatment were observed; anemia was the only grade 3 non-serious adverse event related to both treatments. Utomilumab systemic exposure appeared to increase with dose. One patient with PD-L1-refractory squamous lung cancer achieved a best overall response of partial response and 9 patients had a best overall response of stable disease. No patients achieved complete response. Objective response rate was 4.2% (95% confidence interval: 0.1-21.1%) per RECIST 1.1. Depletion of Tregs in peripheral blood was accompanied by evidence of T-cell expansion as assessed by T-cell receptor sequence analysis.

CONCLUSIONS

The combination of utomilumab/mogamulizumab was safe and tolerable, and may be suitable for evaluation in settings where CCR4-expressing Tregs are suppressing anticancer immunity.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02444793.

Clinical impact of T cells, B cells and the PD-1/PD-L1 pathway in muscle invasive bladder cancer: a comparative study of transurethral resection and cystectomy specimens

In patients with muscle invasive bladder cancer (MIBC), neoadjuvant chemotherapy (NAC) prior to radical cystectomy has improved survival but there is an urgent unmet need to identify prognostic and predictive biomarkers to stratify patients who will benefit from treatment. This study aimed to examine the composition of tumor-infiltrating immune cells in MIBC, with particular reference to the clinical outcome and the potential modifying effect of NAC. To this end, the expression of CD8⁺ and FoxP3⁺ T cells, CD20⁺ B cells, PD-1⁺ and PD-L1⁺ immune cells and PD-L1⁺ tumor cells was evaluated by immunohistochemistry on tissue microarrays with paired transurethral resection (TURB) specimens, cystectomy specimens and lymph node metastases from 145 patients, 65 of whom had received NAC. Kaplan–Meier and Cox regression analyses were applied to assess the impact of investigated cell subsets on time to recurrence (TTR). In cystectomy specimens, high infiltration of the investigated immune cell populations, but not PD-L1⁺ tumor cells, were independently associated with a prolonged TTR, whereas in TURB specimens, this association was only seen for CD8⁺ lymphocytes. An additive beneficial prognostic effect of NAC was seen for the majority of the cell subsets but there was no significant interaction between any immune marker and NAC in relation to TTR. Furthermore, no differences in cell densities prior to NAC treatment were observed between complete and non-complete responders, or pre- and posttreatment in non-complete responders. In conclusion, immune cell infiltration provides important prognostic information in both pre- and postsurgical samples of MIBC, independently of NAC.

Integrative Metabolomic and Transcriptomic Analysis for the Study of Bladder Cancer

Metabolism reprogramming is considered a hallmark of cancer. The study of bladder cancer (BC) metabolism could be the key to developing new strategies for diagnosis and therapy. This work aimed to identify tissue and urinary metabolic signatures as biomarkers of BC and get further insight into BC tumor biology through the study of gene-metabolite networks and the integration of metabolomics and transcriptomics data. BC and control tissue samples (n = 44) from the same patients were analyzed by High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance and microarrays techniques. Besides, urinary profiling study (n = 35) was performed in the same patients to identify a metabolomic profile, linked with BC tissue hallmarks, as a potential non-invasive approach for BC diagnosis. The metabolic profile allowed for the classification of BC tissue samples with a sensitivity and specificity of 100%. The most discriminant metabolites for BC tissue samples reflected alterations in amino acids, glutathione, and taurine metabolic pathways. Transcriptomic data supported metabolomic results and revealed a predominant downregulation of metabolic genes belonging to phosphorylative oxidation, tricarboxylic acid cycle, and amino acid metabolism. The urinary profiling study showed a relation with taurine and other amino acids perturbed pathways observed in BC tissue samples, and classified BC from non-tumor urine samples with good sensitivities (91%) and specificities (77%). This urinary profile could be used as a non-invasive tool for BC diagnosis and follow-up.

Clinical utility of pembrolizumab in the management of advanced solid tumors: an evidence-based review on the emerging new data

Pembrolizumab is a full-length human immunoglobulin G4 (IgG4) monoclonal antibody directed against the immune checkpoint PD-1 to remove its binding with PD-L1 and thus to restore an anti-tumor immune response of T cells. Pembrolizumab is one of the most advanced immune checkpoint inhibitors for cancer care. Apart from rare and serious adverse effects, its favorable tolerance profile enables to treat fragile patients who have often no other choice than best supportive care. The effective retained dose of pembrolizumab is a venous administration of 200 mg every 3 weeks until disease progression, intolerance or up to 24 months. Pembrolizumab has already proven its efficacy and thus obtained marketing authorization in so-called hot or hypermutated tumors or tumors expressing PD-L1 such as melanomas, non-small cell lung cancers, urothelial carcinomas, cervical cancer, etc. Pembrolizumab is also authorized in the United States in the treatment of mismatch repair-deficient tumors or with microsatellite instability. The current challenge is to expand its use in tumor types that are supposed to be less immunogenic, for example, by attempting to warm up the tumor microenvironment, or by combining pembrolizumab with other molecules. An acceptable toxicity profile of such combinations remains to explore. We review here the current indications of this drug, the main prognostic and predictive factors of its efficacy as well as the potential forthcoming indications.

Drug strategies for bladder cancer in the elderly: is there promise for the future?

INTRODUCTION

Bladder cancer (BCa) is a disease that predominantly affects adult and elderly populations. As people live longer, it will become even more frequent and consequently represents a big health problem for health-care providers and is a challenging clinical dilemma. In the elderly, the treatment of BCa presents some peculiarities due to its more aggressive behavior and reduced patient reserves, impacting their response to medical and surgical therapies.

AREAS COVERED

The authors provide a non-systematic review of the literature using PubMed to obtain an overview of the therapeutic options for BCa in the elderly, from the low-risk non-muscle-invasive setting to muscle-invasive and advanced/metastatic disease.

EXPERT OPINION

The main challenge in the treatment of BCa in the elderly is represented by the need to find a compromise between the risk of under- and overtreatment. The wide spectrum of disease prognoses between low-risk non-muscle invasive BCa and invasive metastatic disease represents a perfect setting for a personalized approach. To pursue this aim, older patients need a multidisciplinary approach and clinical management, in order to optimize oncological outcomes as well as to face and support their frailty during cancer therapies.

A Combination of Positive Tumor HLA-I and Negative PD-L1 Expression Provides an Immune Rejection Mechanism in Bladder Cancer

BACKGROUND

Tumor human leukocyte antigen class I (HLA-I) expression plays an important role in T cell-mediated tumor rejection. Loss of HLA-I is associated with cancer progression and resistance to immunotherapy, including antibodies blocking programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) signaling. Our objective was to analyze a correlation between HLA-I, tumor immune infiltration, and PD-L1/PD-1 axis in bladder cancer in association with the clinicopathologic features of patients.

METHODS

We analyzed 85 cryopreserved bladder tumors by immunohistochemistry to investigate the expression of HLA-I, PD-L1, PD-1, CD3, CD8, and CXC chemokine receptor 4 (CXCR4). The results were correlated with tumor stage and other clinicopathologic variables of patients.

RESULTS

We found a strong positive correlation between tumor HLA-I expression and infiltration with CD3+ and CD8 + T cells. PD-L1 expression was positive in 15.5% of tumors and heterogeneous in 40.5%, and was linked to a more advanced tumor stage. The majority of HLA-I-positive/heterogeneous tumors also expressed PD-L1 and PD-1, which were significantly correlated with each other and with lymphocyte infiltration. Interestingly, the analysis of the simultaneous expression of both markers revealed that 85.2% of tumors with a positive/heterogeneous HLA-I phenotype and negative for PD-L1 were mostly non-invasive, representing a 'tumor rejection' immune phenotype.

CONCLUSIONS

High tumor HLA-I expression with absence of PD-L1 provides bladder cancer with an immune rejection mechanism. Evaluation of PD-L1 and HLA-I together should be considered in bladder cancer and may provide a new predictive biomarker of tumor invasiveness and of the response to 'immune checkpoint' therapy.

Targeted therapies in urothelial bladder cancer: a disappointing past preceding a bright future?

Bladder cancer (BC) is the most frequent cancer affecting the urinary tract. With the growing era of targeted therapies around the 2000s, many trials evaluated the efficacy of targeted therapy in advanced BC. However, no approval was given yet to any form of targeted therapy when it comes to BC. The aim of this paper was to report the most pivotal trials that evaluated different families of targeted therapy in the treatment of BC, according to their biomarkers (FGFR3, EGFR, HER2, VEGF and PI3K/AKT/mTOR). The ongoing trials testing targeted therapies in advanced BC were then summarized. Finally, the different immunotherapies approved for this disease and their potential combination with targeted therapy were addressed.

Pembrolizumab in the treatment of locally advanced or metastatic urothelial carcinoma: clinical trial evidence and experience

The treatment of advanced urothelial carcinoma (UC) has dramatically changed with the advent of immune checkpoint inhibitors that disrupt the T-cell inhibitory interaction between the programmed cell death (PD)-1 receptor and its ligand (PD-L1). Pembrolizumab, a highly specific, monoclonal antibody directed against PD-1, has demonstrated clinical efficacy as well as a favorable toxicity profile, and has emerged as a new standard of care in the treatment of advanced UC. This review will summarize clinical efficacy from recent trials that led to the approval of pembrolizumab in treating platinum-refractory advanced UC as well as treating patients who are ineligible for first-line cisplatin-containing chemotherapy. While immune checkpoint inhibition has reinvigorated the treatment landscape of advanced UC and generated a great deal of optimism, only a minority of patients benefit. Combination strategies with the goal of increasing response rates are desperately needed as are biomarkers predictive of response.

The Impact of Cisplatin- or Non-Cisplatin-Containing Chemotherapy on Long-Term and Conditional Survival of Patients with Advanced Urinary Tract Cancer

BACKGROUND

The impact of cisplatin use on long-term survival of unselected patients with advanced urinary tract cancer (aUTC) has not been adequately investigated. We used a multinational database to study long-term survival and the impact of treatment type in unselected patients with aUTC.

MATERIALS AND METHODS

A total of 1,333 patients with aUTC (cT4bN0M0, cTanyN+M0, cTanyNanyM+), transitional-cell, squamous, or adenocarcinoma histology who received systemic chemotherapy and had available survival data were selected. Long-term survival was defined as alive at 3 years following initiation of first-line chemotherapy. Conditional overall survival (COS) analysis was employed to study change in prognosis given time survived from initiation of first-line chemotherapy.

RESULTS

Median follow-up was 31.7 months. The combination of cisplatin use and cisplatin eligibility accurately predicted long-term survival. Eligible patients treated with cisplatin conferred a 31.6% probability of 3-year survival (95% confidence interval [CI]: 25.1-38.3), and 2-year COS for patients surviving 3 years after initiation of cisplatin-based chemotherapy was 83% (95% CI: 59.7-93.5). The respective probabilities for patients who were ineligible for cisplatin or not treated with cisplatin despite eligibility were 14% (95% CI: 10.8-17.6) and 49.3% (95% CI: 28.2-67.4). Two-year COS remained significantly different between these two groups up to 3 years after chemotherapy initiation.

CONCLUSION

Cisplatin-based therapy was associated with the highest likelihood of long-term survival in patients with aUTC and should be used in patients who fulfill the established eligibility criteria. Novel therapies are necessary to increase long-term survival in cisplatin-ineligible patients.

IMPLICATIONS FOR PRACTICE

Long-term, disease-free survival is possible in one in four eligible-for-cisplatin patients with advanced urinary tract cancer (aUTC) treated with cisplatin-based combination chemotherapy. Therefore, deviations from eligibility criteria should be avoided. Consolidation surgery should be considered in responders. These data provide benchmarks for the study of novel therapies in aUTC.

Immunotherapy in Bladder Cancer

BACKGROUND

Bladder cancer is the fifth most common cancer in the United States. Cisplatin-based chemotherapy is the current standard of care in stage IV bladder cancer. It has increased overall survival but rarely results in complete remission, with an overall survival of 14-15 months. The most significant breakthrough in cancer therapy over the last decade was the development of immunotherapy.

DATA SOURCES

KEYNOTE-045, IMvigor211, CheckMate275, Javelin Solid Tumor, MEDI4736, and KEYNOTE-0528 clinical trials.

AREAS OF UNCERTAINTY

There are ongoing clinical trials using combination of immunotherapy and chemotherapy as first line of therapy in the setting of metastatic urothelial cancer and also to determine the duration of treatment.

THERAPEUTIC ADVANCES

Immunotherapy is approved as a second-line treatment for metastatic urothelial cancer. Their use as a first-line agent is only limited to patients who are ineligible for cisplatin-based treatments. Five drugs are approved by Food and Drug Administration for metastatic urothelial cancer including 3 Programmed cell-death protein 1 (PD-1) inhibitors and 2 programmed cell-death ligand 1 (PD-L1) inhibitors in patients who have progressed during or after platinum-based therapy. Pembrolizumab, nivolumab, and atezolizumab are PD-1 inhibitors. Durvalumab and avelumab are PD-L1 inhibitors. However, only 2 drugs were approved based on phase III clinical trials-pembrolizumab and atezolizumab, of which only KEYNOTE study performed with pembrolizumab showed overall survival difference. Atezolizumab and pembrolizumab are the Food and Drug Administration-approved checkpoint inhibitors in cisplatin-ineligible patients.

CONCLUSION

This review article summarizes the significance of immunotherapy in treatment of bladder cancer, its side effects, and limitations.