Emerging role of immunotherapy in urothelial carcinoma—Advanced disease

Chemotherapy, immunotherapy, or combination first-line treatment for metastatic urothelial carcinoma of the bladder: A large real-world experience

INTRODUCTION

First-line systemic therapy for metastatic urothelial carcinoma of the bladder (mUC) consists of platinum-based chemotherapy in most patients and PD1/L1 inhibitors in selected patients. Multiple combination chemoimmunotherapy trials failed to show a clear benefit over chemotherapy alone. We used real-world data to evaluate clinical and sociodemographic factors associated with receipt of first-line chemotherapy, immunotherapy, or combination chemoimmunotherapy treatment for metastatic bladder cancer and examined differences in overall survival (OS).

MATERIALS AND METHODS

We used the National Cancer Database to identify patients with stage IV mUC diagnosed between 2014 and 2018, who were treated with first-line immunotherapy, chemotherapy, or combination treatment. We performed multivariable logistic regression modeling to determine factors associated with treatment receipt Adjusted Kaplan-Meier survival analysis and multivariable Cox proportional hazards regression were used to evaluate the association between treatment and OS.

RESULTS

In our cohort of 4,169 patients, multivariable analysis identified increasing age (RRR: 1.07, 95%CI, 1.06-1.08) and comorbidity burden (, as independent predictors of receiving immunotherapy. Treatment at an academic facility was associated with increased likelihood of combination treatment (RRR: 1.29, 95%CI, 1.01-1.65). After IPTW, we found that combination therapy (hazard ratio [HR]: 0.72; 95%CI, 0.62-0.83) was associated with improved survival compared to chemotherapy.

CONCLUSIONS

Patients with older age and more comorbidities were more likely to receive immunotherapy than chemotherapy for first-line treatment of metastatic urothelial carcinoma of the bladder. Utilization of chemoimmunotherapy was observed to be higher in academic centers and was associated with improved survival compared to chemotherapy.

Real-world epidemiology and treatment patterns of patients with locally advanced or metastatic urothelial carcinoma: Retrospective analysis of Diagnosis Procedure Combination claims data in Japan

OBJECTIVES

Evaluate real-world epidemiologic trends and treatment patterns in newly diagnosed patients with locally advanced or metastatic urothelial carcinoma (la/mUC) in Japan.

METHODS

This retrospective analysis included adults with newly diagnosed la/mUC in Japan (January 2015-December 2019) from a nationwide-linked electronic medical record Diagnostic Procedure Combination claims dataset. Outcomes included epidemiologic trends (incidence and prevalence), baseline demographics, clinical characteristics, and treatment patterns in newly diagnosed patients with la/mUC before (2015-2017) and after (2018-2019) approval of pembrolizumab in Japan.

RESULTS

Of 975 patients included, 76.4% were men; 71.6% were aged 70 years or older. Most cases (70.5%) were of the bladder. Between 2015 and 2019, the annual age-adjusted incidence increased from 6.8 to 12.4 per 100 000; the annual age-adjusted period prevalence increased from 13.0 to 25.2 per 100 000; and 307 (31.5%) and 668 (68.5%) patients were diagnosed from 2015 to 2017 and 2018 to 2019, respectively. Overall, 731 (75%) patients received systemic anticancer therapy; all received 1 line and 50.2% received 2 lines of therapy; 78.3% of patients received gemcitabine plus platinum-based therapy and 2.2% received pembrolizumab as first-line treatment. First-line treatment rates increased from 69.4% to 77.5% after pembrolizumab approval. Of 367 patients who received second-line treatment, 22.3% received gemcitabine plus platinum-based therapy; 14.7% received pembrolizumab.

CONCLUSIONS

In the Japanese regions considered, incidence and prevalence of newly diagnosed la/mUC increased over time and first-line treatment with pembrolizumab increased after approval.

Modification of lysine-260 2-hydroxyisobutyrylation destabilizes ALDH1A1 expression to regulate bladder cancer progression

ALDH1A1 is one of the classical stem cell markers for bladder cancer. Lysine 2-hydroxyisobutyrylation (Khib) is a newfound modification to modulate the protein expression, and the underlying mechanisms of how ALDH1A1 was regulated by Khib modification in bladder cancer remains unknown. Here, ALDH1A1 showed a decreased K260hib modification, as identified by protein modification omics in bladder cancer. Decreasing ALDH1A1 expression significantly suppressed the proliferation, migration and invasion of bladder cancer cells. Moreover, K260hib modification is responsible for the activity of ALDH1A1 in bladder cancer, which is regulated by HDAC2/3. Higher K260hib modification on ALDH1A1 promotes protein degradation through chaperone-mediated autophagy (CMA), and ALDH1A1 K260hib could sensitize bladder cancer cells to chemotherapeutic drugs. Higher ALDH1A1 expression with a lower K260hib modification indicates a poor prognosis in patients with bladder cancer. Overall, we demonstrated that K260hib of ALDH1A1 can be used as a potential therapeutic target for bladder cancer treatment.

FOXA1 repression drives lineage plasticity and immune heterogeneity in bladder cancers with squamous differentiation

Cancers arising from the bladder urothelium often exhibit lineage plasticity with regions of urothelial carcinoma adjacent to or admixed with regions of divergent histomorphology, most commonly squamous differentiation. To define the biologic basis for and clinical significance of this morphologic heterogeneity, here we perform integrated genomic analyses of mixed histology bladder cancers with separable regions of urothelial and squamous differentiation. We find that squamous differentiation is a marker of intratumoral genomic and immunologic heterogeneity in patients with bladder cancer and a biomarker of intrinsic immunotherapy resistance. Phylogenetic analysis confirms that in all cases the urothelial and squamous regions are derived from a common shared precursor. Despite the presence of marked genomic heterogeneity between co-existent urothelial and squamous differentiated regions, no recurrent genomic alteration exclusive to the urothelial or squamous morphologies is identified. Rather, lineage plasticity in bladder cancers with squamous differentiation is associated with loss of expression of FOXA1, GATA3, and PPARG, transcription factors critical for maintenance of urothelial cell identity. Of clinical significance, lineage plasticity and PD-L1 expression is coordinately dysregulated via FOXA1, with patients exhibiting morphologic heterogeneity pre-treatment significantly less likely to respond to immune checkpoint inhibitors.

Immune Checkpoint Inhibitors in Urothelial Bladder Cancer: State of the Art and Future Perspectives

Simple Summary

Urothelial bladder cancer (BC) is one of the most fatal cancers, with a dismal five-year survival rate of 5% in patients with metastatic disease. Clinically relevant benefits of immunotherapy in advanced or metastatic bladder cancer have led to Food and Drug Administration (FDA) approval of immune checkpoint inhibitors (ICIs) as second- or first-line therapy in patients unresponsive to or ineligible for standard treatment. The advantage of ICIs is being investigated in various stages of BC, either as monotherapy or in combination with other drugs. In this review we discuss the role of ICIs in BC, highlighting their current clinical application and outlining future therapeutic perspectives.

Abstract

Bladder cancer (BC) is the most common malignancy of the genitourinary tract, with high morbidity and mortality rates. Until recently, the treatment of locally advanced or metastatic urothelial BC was based on the use of chemotherapy alone. Since 2016, five immune checkpoint inhibitors (ICIs) have been approved by the Food and Drug Administration (FDA) in different settings, i.e., first-line, maintenance and second-line treatment, while several trials are still ongoing in the perioperative context. Lately, pembrolizumab, a programmed death-1 (PD-1) inhibitor, has been approved for Bacillus Calmette–Guérin (BCG)-unresponsive high-risk non-muscle invasive bladder cancer (NMIBC), using immunotherapy at an early stage of the disease. This review investigates the current state and future perspectives of immunotherapy in BC, focusing on the rationale and results of combining immunotherapy with other therapeutic strategies.

Immune Checkpoint Inhibitors for the Treatment of Bladder Cancer

A number of immune checkpoint inhibitors (ICIs) have been approved as first-line therapy in case of cisplatin-ineligible patients or as second-line therapy for patients with metastatic urothelial carcinoma (mUC) of the bladder. About 30% of patients with mUC will respond to ICIs immunotherapy. Programmed death-ligand 1 (PD-L1) expression detected by immunohistochemistry seems to predict response to immune checkpoint inhibitors in patients with mUC as supported by the objective response rate (ORR) and overall survival (OS) associated with the response observed in most clinical trials. Pembrolizumab, an anti-PD-1 antibody, demonstrated better OS respective to chemotherapy in a randomized phase 3 study for second-line treatment of mUC. Nivolumab, a PD-1 antibody, also demonstrated an OS benefit when compared to controls. Atezolizumab, Durvalumab, and Avelumab antibodies targeting PD-L1 have also received approval as second-line treatments for mUC with durable response for more than 1 year in selected patients. Atezolizumab and Pembrolizumab also received approval for first-line treatment of patients that are ineligible for cisplatin. A focus on the utility of ICIs in the adjuvant or neoadjuvant setting, or as combination with chemotherapy, is the basis of some ongoing trials. The identification of a clinically useful biomarker, single or in association, to determine the optimal ICIs treatment for patients with mUC is very much needed as emphasized by the current literature. In this review, we examined relevant clinical trial results with ICIs in patients with mUC alone or as part of drug combinations; emphasis is also placed on the adjuvant and neoadjuvant setting. The current landscape of selected biomarkers of response to ICIs including anti-PD-L1 immunohistochemistry is also briefly reviewed.

ATM Mutations Benefit Bladder Cancer Patients Treated With Immune Checkpoint Inhibitors by Acting on the Tumor Immune Microenvironment

Immune checkpoint inhibitors (ICIs) have shown promising results in bladder cancer (BC). However, only some patients respond to ICIs. DNA repair defects (DDR) play an important role in the therapeutic response of bladder cancer. Therefore, we aimed to elucidate the association between ICIs in bladder cancer and ataxia telangiectasia mutated (ATM), a core component of the DNA repair system. From a collected immunotherapy cohort (n = 210) and The Cancer Genome Atlas (TCGA)-Bladder cancer cohort, which were both retrieved from publicly available resources, we performed a series of analyses to evaluate the prognostic value and potential mechanism of ATM in bladder cancer immunotherapy. We found that ATM-mutant (ATM-MT) bladder cancer patients derived greater benefit from ICIs [overall survival (OS), hazard ratio (HR) = 0.28, [95% confidence interval (CI), 0.16 to 0.51], P = 0.007] and showed a higher mutation load (P < 0.05) and immunogenicity (P < 0.05) than ATM-wild-type (ATM-WT) patients. The immune inflammatory response to antigenic stimulation, the regulation of the IFN pathway and the macrophage activation pathway were significantly enriched in the ATM-MT group (NES > 1, P < 0.05), while insulin-like growth factor receptor signaling pathways and vasculogenesis were significantly downregulated (NES < −1, P < 0.05). ATM mutation significantly upregulated the number of DNA damage repair pathway gene mutations (P < 0.05). ATM mutations resulted in increased bladder cancer sensitivity to 29 drugs (P < 0.05), including cisplatin and BMS-536924, an IGF-1R inhibitor. Our results demonstrate the importance of ATM as a prognostic signature in bladder cancer and reveal that ATM may impact the effects of ICIs by acting on the tumor immune microenvironment.

Identification of 9-Core Immune-Related Genes in Bladder Urothelial Carcinoma Prognosis

Background: Immune microenvironment within tumors affects initiation, progression and clinical outcome of human cancers. Here we explored an immune-related gene signature associated with prognosis of patients with bladder urothelial carcinoma. Method: The Cancer Genome Atlas (TCGA) database was interrogated for expressions of immune-related genes in bladder urothelial carcinomas. Integrated bioinformatics analyses were performed to identify prognostic factors. Results: Twenty-seven immune-related genes were revealed significantly associated with patient's overall survival (OS) by univariate Cox proportional hazards regression analysis. Nine-core immune-related genes including MMP9, PDGFRA, AHNAK, OLR1, RAC3, IGF1, PGF, OAS1, and SH3BP2 were selected to construct a risk score model by multivariate Cox proportional hazards regression analysis. Bioinformatics analyses further validated that risk score could be used as an important independent factor in evaluating prognosis. Conclusion: We established a prognostic immune signature for patients with bladder urothelial carcinoma, which may provide novel targets for prediction and therapy of these patients.

Tumor-associated macrophages expressing galectin-9 identify immunoevasive subtype muscle-invasive bladder cancer with poor prognosis but favorable adjuvant chemotherapeutic response

PURPOSE

Tumor-associated macrophages (TAMs) exist as heterogeneous subsets and have dichotomous roles in cancer-immune evasion. This study aims to assess the clinical effects of Galectin-9⁺ tumor-associated macrophages (Gal-9⁺TAMs) in muscle-invasive bladder cancer (MIBC).

EXPERIMENTAL DESIGN

We identified Gal-9⁺TAMs by immunohistochemistry (IHC) analysis of a tumor microarray (TMA) (n = 141) from the Zhongshan Hospital and by flow cytometric analysis of tumor specimens (n = 20) from the Shanghai Cancer Center. The survival benefit of platinum-based chemotherapy in this subpopulation was evaluated. The effect of the tumor-immune microenvironment with different percentages of Gal-9⁺TAMs was explored.

RESULTS

The frequency of Gal-9⁺TAMs increased with tumor stage and grade. Gal-9⁺TAMs predicted poor overall survival (OS) and recurrence-free survival (RFS) and were better than Gal-9^-TAMs and TAMs to discriminate prognostic groups. In univariate and multivariate Cox regression analyses, patients with high percentages of Gal-9⁺TAMs showed the prominent survival benefit after receiving adjuvant chemotherapy (ACT). High Gal-9⁺TAM infiltration correlated with increasing numbers of regulatory T cells (Tregs) and mast cells and decreasing numbers of CD8⁺T and dendritic cells (DCs). Dense infiltration of Gal-9⁺TAMs was related to reduced cytotoxic molecules, enhanced immune checkpoints or immunosuppressive cytokines expressed by immune cells, as well as active proliferation of tumor cells. Additionally, the subpopulation accumulated was strongly associated with PD-1⁺TIM-3⁺CD8⁺T cells.

CONCLUSIONS

Gal-9⁺TAMs predicted OS and RFS and response to ACT in MIBC patients. High Gal-9⁺TAMs were associated with a pro-tumor immune contexture concomitant with T cell exhaustion.

The multifaceted immune regulation of bladder cancer

Bladder cancer is an important public health concern owing to its prevalence, high recurrence risk and treatment failures. Maintaining the equilibrium between prompt and effective immunity and an excessive and protracted immune response is critical for successful immune defence. This delicate balance is ensured by intrinsic or extrinsic immunoregulatory mechanisms. Intrinsic control of immune cell activation is mediated by stimulatory and inhibitory receptors expressed on the effector cell itself, whereas extrinsic control is mediated via other immune cells by cell-cell contact and/or secretion of inhibitory factors. Tumours can exacerbate these immunosuppressive pathways, fostering a tolerant microenvironment. These mechanisms have previously been poorly described in urothelial carcinoma, but a growing body of evidence highlights the key role of immune regulation in bladder cancer. This process includes immune checkpoints (mostly programmed cell death 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1)), as well as regulatory T cells, myeloid-derived suppressor cells, tumour-associated macrophages and type 2 innate and adaptive lymphocytes. For each component, quantitative and qualitative alterations, clinical relevance and potential targeting strategies are currently being explored. An improved understanding of immune regulation pathways in bladder cancer development, recurrence and progression will help in the design of novel diagnostic and prognostic tools as well as treatments.

Cisplatin contributes to programmed death-ligand 1 expression in bladder cancer through ERK1/2-AP-1 signaling pathway

Bladder cancer (BC) is the second most common urologic malignancy and the ninth most common malignancy worldwide. Surgical resection is the mainstay of treatment for patients with early-stage disease, whereas therapeutic options are limited for patients with advanced-stage or residual BC. Programmed cell death ligand-1 (PD-L1) is an important target for immunotherapy. It is known that PD-L1 is overexpressed in BC; a clinical trial involving PD-L1 immune checkpoint inhibitors in advanced BC is ongoing. In the present study, we used Western blot and quantitative real-time PCR (qPCR) to define the expression level of PD-L1 after cisplatin treatment in BC-derived cell lines. The signal activation was also evaluated by Western blot in BC-derived cell lines. We found that chemotherapeutic drug cisplatin can induce PD-L1 but not PD-L2 expression in BC-derived cell lines. Furthermore, the expression level of PD-L1 was increased in a dose- and time-dependent manner after cisplatin treatment. The cisplatin-induced PD-L1 expression is mainly mediated by ERK1/2 but not Akt/mTOR signal pathway. Moreover, we found that cisplatin activates transcription factor activator protein-1 (AP-1) to regulate PD-L1 expression. The chemotherapy drug such as cisplatin may trigger resistance of BC through PD-L1 up-regulation. The present study suggests that PD-L1 antibody should be used concomitantly with chemotherapy in the setting of advanced and metastatic BC.

Exploring the Pathological Mechanism of Bladder Cancer Based on Tumor Mutational Burden Analysis

Although immunotherapy has progressed in the treatment of bladder cancer, some patients still have poor prognosis. New therapeutic targets are eager to be discovered to improve the outcomes of bladder cancer. With the development of high-throughput sequencing and tumor profiling, potential tumor biomarkers were identified. Through the interpretation of related data from the Cancer Genome Atlas database (TCGA), some key genes have been discovered to drive the development and prognosis of urinary bladder neoplasm. On account of the success of immunotherapy in many cancer types, we established the relationship between tumor mutation burden and immune microenvironment of bladder cancer and found the changes of several immune cells in this disease. Based on the understanding of the bladder tumor genome and immune environment, this study is supposed to provide new therapies for the treatment of bladder neoplasm.

The current state of molecular testing in the treatment of patients with solid tumors, 2019

The world of molecular profiling has undergone revolutionary changes over the last few years as knowledge, technology, and even standard clinical practice have evolved. Broad molecular profiling is now nearly essential for all patients with metastatic solid tumors. New agents have been approved based on molecular testing instead of tumor site of origin. Molecular profiling methodologies have likewise changed such that tests that were performed on patients a few years ago are no longer complete and possibly inaccurate today. As with all rapid change, medical providers can quickly fall behind or struggle to find up-to-date sources to ensure he or she provides optimum care. In this review, the authors provide the current state of the art for molecular profiling/precision medicine, practice standards, and a view into the future ahead.

Urothelial cancer: a narrative review of the role of novel immunotherapeutic agents with particular reference to the management of non-muscle-invasive disease

AIM

This narrative review describes current guidelines for treating NMIBC, provides an overview of the principle behind immune checkpoint inhibition, and summarizes current evidence for checkpoint inhibitors in urothelial malignancy. Further, we discuss potential strategies for immune checkpoint inhibition in the management of NMIBC.

BACKGROUND

Adjuvant intravesical BCG immunotherapy has been the mainstay of treatment for high-risk non-muscle-invasive bladder cancer (NMIBC) for decades but is associated with both a significant side effect profile and failure rate. Recently, a substantial body of trial data has been published demonstrating the successful use of systemic immunotherapy in the treatment of advanced urothelial malignancy and, in particular, a class of drugs known as 'immune checkpoint inhibitors'. This has led to the approval of a number of these drugs by the UK National Institute of Health and Care Excellence and the US Food and Drug Administration, and ongoing trials are examining use in the management of NMIBC.

METHODS

To identify relevant published data, using the PubMed/ Medline search engine, an online search of the Pubmed/ Medline archives was conducted using the terms bladder cancer' in combination with 'checkpoint inhibitors', and limited to articles in English published between 1966 and September 2017.To identify ongoing trials of interest but not yet published, a further search of the clinical trials.gov search engine was conducted using the term 'non-muscle-invasive bladder cancer'.

CONCLUSION

There has been little advance in available adjuvant therapy for NMIBC treated with TURBT. Current intravesical therapies are associated with a high recurrence rate and significant side effect profile. The impending publication of the wealth of ongoing trials, both into the delivery and efficacy of checkpoint inhibition will direct the future treatment of NMIBC.

Treatment resistance in urothelial carcinoma: an evolutionary perspective

The emergence of treatment-resistant clones is a critical barrier to cure in patients with urothelial carcinoma. Setting the stage for the evolution of resistance, urothelial carcinoma is characterized by extensive mutational heterogeneity, which is detectable even in patients with early stage disease. Chemotherapy and immunotherapy both act as selective pressures that shape the evolutionary trajectory of urothelial carcinoma throughout the course of the disease. A detailed understanding of the dynamics of evolutionary drivers is required for the rational development of curative therapies. Herein, we describe the molecular basis of the clonal evolution of urothelial carcinomas and the use of genomic approaches to predict treatment responses. We discuss various mechanisms of resistance to chemotherapy with a focus on the mutagenic effects of the DNA dC->dU-editing enzymes APOBEC3 family of proteins. We also review the evolutionary mechanisms underlying resistance to immunotherapy, such as the loss of clonal tumour neoantigens. By dissecting treatment resistance through an evolutionary lens, the field will advance towards true precision medicine for urothelial carcinoma.

Revisiting Histone Deacetylases in Human Tumorigenesis: The Paradigm of Urothelial Bladder Cancer

Urinary bladder cancer is a common malignancy, being characterized by substantial patient mortality and management cost. Its high somatic-mutation frequency and molecular heterogeneity usually renders tumors refractory to the applied regimens. Hitherto, methotrexate-vinblastine-adriamycin-cisplatin and gemcitabine-cisplatin represent the backbone of systemic chemotherapy. However, despite the initial chemosensitivity, the majority of treated patients will eventually develop chemoresistance, which severely reduces their survival expectancy. Since chromatin regulation genes are more frequently mutated in muscle-invasive bladder cancer, as compared to other epithelial tumors, targeted therapies against chromatin aberrations in chemoresistant clones may prove beneficial for the disease. “Acetyl-chromatin” homeostasis is regulated by the opposing functions of histone acetyltransferases (HATs) and histone deacetylases (HDACs). The HDAC/SIRT (super-)family contains 18 members, which are divided in five classes, with each family member being differentially expressed in normal urinary bladder tissues. Since a strong association between irregular HDAC expression/activity and tumorigenesis has been previously demonstrated, we herein attempt to review the accumulated published evidences that implicate HDACs/SIRTs as critical regulators in urothelial bladder cancer. Moreover, the most extensively investigated HDAC inhibitors (HDACis) are also analyzed, and the respective clinical trials are also described. Interestingly, it seems that HDACis should be preferably used in drug-combination therapeutic schemes, including radiation.

New combinatorial strategies to improve the PARP inhibitors efficacy in the urothelial bladder Cancer treatment

BACKGROUND

Novel therapeutic strategies are urgently needed for the treatment of metastatic Urothelial Bladder Cancer. DNA damaging repair (DDR) targeting has been introduced in cinical trials for bladder cancer patients that carry alterations in homologous DNA repair genes, letting to envisage susceptibility to the Poly (adenosine diphosphate [ADP]) ribose polymerase (PARP) inhibitors.

MAIN BODY

PARP inhibition, by amplifying the DNA damage, augments the mutational burden and promotes the immune priming of the tumor by increasing the neoantigen exposure and determining upregulation of programmed death ligand 1 (PD-L1) expression. Thus, the combination of PARP-inhibition and the PD/PD-L1 targeting may represent a compelling strategy to treat bladder cancer and has been introduced in recent clinical trials. The targeting of DDR has been also used in combination with epigenetic drugs able to modulate the expression of genes involved in DDR, and also able to act as immunomodulator agents suggesting their use in combination with immune-checkpoint inhibitors.

CONCLUSION

In conclusion, it may be envisaged the combination of three classes of drugs to treat bladder cancer, by targeting the DDR process in a tumor context of DDR defect, together with epigenetic agents and immune-checkpoint inhibitors, whose association may amplify the effects and reduce the doses and the toxicity of each single drug.

CCDC6 and USP7 expression levels suggest novel treatment options in high-grade urothelial bladder cancer

Background

The muscle invasive form of urothelial bladder cancer (UBC) is a deadly disease. Currently, the therapeutic approach of UBC is mostly based on surgery and standard chemotherapy.

Biomarkers to establish appropriate drugs usage are missing. Deficiency of the tumor suppressor CCDC6 determines PARP-inhibitor sensitivity. The CCDC6 levels are modulated by the deubiquitinase USP7. In this work we scored CCDC6 and USP7 expression levels in primary UBC and we evaluated the expression levels of CCDC6 in correlation with the effects of the PARP-inhibitors combined with the USP7 inhibitor, P5091, in vitro. Since PARP-inhibitors could be enhanced by conventional chemotherapy or DNA damage inducers, we tested the new agent RRx-001, able to induce DNA damage, to prove the benefit of combined treatments in bladder cancer cells.

Methods

The J82, T24, 5637 and KU-19-19 bladder cancer cells were exposed to USP7 inhibitor P5091 in presence of cycloheximide to analyse the CCDC6 stability. Upon the CCDC6 degradation induced by P5091, the cells sensitivity to PARP-inhibitor was evaluated by cell viability assays. The ability of the DNA damage inducer RRx-001 to modulate CCDC6 protein levels and H2AX phosphorylation was detected at immunoblot. The combination of USP7 inhibitor plus RRx-001 enhanced the PARP-inhibitor sensitivity, as evaluated by cell viability assays. The results of the scores and correlation of CCDC6 and USP7 expression levels obtained by UBC primary biopsies staining were used to cluster patients by a K-mean cluster analysis.

Results

P5091 determining CCDC6 degradation promoted bladder cancer cells sensitivity to PARP-inhibitor drugs. RRx-001, by inducing DNA damage, enhanced the effects of the combined treatment. The immunohistochemical staining of both CCDC6 and USP7 proteins allowed to cluster the high grade (G3) UBC patients, on the basis of CCDC6 expression levels.

Conclusions

In high grade UBC the identification of two clusters of patients based on CCDC6 and USP7 expession can possibly indicate the use of PARP-inhibitor drugs, in combination with USP7 inhibitor in addition to the DNA damage inducer RRx-001, that also acts as an immunomodulatory agent, offering novel therapeutic strategy for personalized medicine in bladder cancer patients.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1087-1) contains supplementary material, which is available to authorized users.

Landscape of Tumor Mutation Load, Mismatch Repair Deficiency, and PD-L1 Expression in a Large Patient Cohort of Gastrointestinal Cancers

The efficacy of immunotherapy varies widely among different gastrointestinal cancers. Response to immune checkpoint inhibitors is shown to correlate with tumor mutation load (TML), mismatch repair deficiency (dMMR) status, and programmed cell death-ligand 1 (PD-L1) expression. Herein, we quantify TML, dMMR, and PD-L1 expression and determine their interrelationship in gastrointestinal cancers. Here, a total of 4,125 tumors from 14 different gastrointestinal cancer sites were studied using validated assays. Next-generation sequencing was performed on genomic DNA isolated from formalin-fixed paraffin-embedded tumor specimens using the NextSeq platform. TML was calculated using only somatic nonsynonymous missense mutations sequenced with a 592-gene panel. Microsatellite instability (MSI) was assessed using direct analysis of altered known MSI loci in the target regions of the sequenced genes. PD-L1 expression was analyzed by IHC. Interestingly, right-sided colon and small-bowel adenocarcinomas had the highest prevalence of TML-high tumors (14.6% and 10.2%, respectively). Pancreatic neuroendocrine tumors and gastrointestinal stromal tumors had the lowest rates of TML-high (1.3% and 0%, respectively). TML-high was strongly associated with MSI-H (P < 0.0001). However, all TML-high anal cancers (8.3%) were microsatellite stable (MSS). Higher PD-L1 expression was more likely to be seen in MSI compared with MSS tumors (20.6% vs. 7.8%, P < 0.0001).Implications: TML-high rate varied widely among gastrointestinal cancers. Although MSI is conceivably the main driver for TML-high, other factors may be involved. Future clinical trials are needed to evaluate whether the integration of TML, MSI, and PD-L1 could better identify potential responders to immunotherapy. Mol Cancer Res; 16(5); 805-12. ©2018 AACR.

Current markers and their value in the era of immuno-oncology

Immunotherapy in urothelial cancer is a quickly evolving field as new agents are being investigated in multiple clinical trials and various clinical settings. The purpose of this review is to provide an insight into the mechanism of these treatments, potential targets to evaluate treatment response and to give an update on the current status of clinical trials. Urothelial cancer is a polyclonal disease with a substantial tumor heterogeneity and a high mutational load which may be beneficial as this may trigger a stronger T-cell mediated immune response. PD-1 expression has been shown to correlate with stage, grade, progression and poorer survival but it appears challenging to be utilized as a predictor for treatment response in urothelial cancer. Another important concept is immune cell (IC) infiltration, which is a reflection of the activated immune response within the target tissue. Marker genes may represent signaling pathways involved in T-cell recognition and lysis of T-cells. The complexity of the tumor and host interaction requires multiple concepts to be integrated into a future model to assess treatment response. We have evaluated multiple biomarker approaches currently investigated in clinical trials in urothelial cancer.

Atezolizumab in urothelial bladder carcinoma

Metastatic bladder cancer is an aggressive malignancy with a poor prognosis when presenting with advanced stage. Cisplatin-based therapy has been the mainstay of first-line treatment but therapy in second-line setting has been an unmet medical need for decades. Moreover, many patients are unable to receive cisplatin-based therapy. Recently, immune-checkpoint inhibitors transformed the management and prognosis of many malignancies and will certainly redefine the standard of care for bladder cancer. Atezolizumab, an anti-PD-L1 antibody, was the first immune-checkpoint inhibitor to be approved by the US FDA in May 2016 for patients with urothelial carcinoma. In this review, we discuss the evidence behind this promising drug.

The role of pazopanib on tumour angiogenesis and in the management of cancers: A review

Pazopanib is a relatively new compound to be introduced into the chemotherapy field. It is thought to have decent anti-angiogenic properties, which gives an additional hope for the treatment of certain types of cancers. A systematic review solely discussing about pazopanib and its anti-angiogenic effect is yet to be published to date, despite several relevant clinical trials being conducted over the recent years. In this review, we aim to investigate the mechanism of pazopanib's anti-angiogenic effect and its effectiveness in treating several cancers. We have included, in this study, findings from electronically searchable data from randomized clinical trials, clinical studies, cohort studies and other relevant articles. A total of 352 studies were included in this review. From the studies, the effect of pazopanib in various cancers or models was observed and recorded. Study quality is indefinite, with a few decent quality articles. The most elaborately studied cancers include renal cell carcinoma, solid tumors, advanced solid tumors, soft tissue sarcoma, breast cancer and gynecological cancers. In addition, several less commonly studied cancers are included in the studies as well. Pazopanib had demonstrated its anti-angiogenic effect based on favorable results observed in cancers, which are caused by angiogenesis-related mechanisms, such as renal cell carcinoma, solid tumors, advanced solid tumors and soft tissue sarcoma. This review was conducted to study, analyze and review the anti-angiogenic properties of pazopanib in various cancers. The results obtained can provide a decent reference when considering treatment options for angiogenesis-related malignancies. Furthermore, the definite observations of the anti-angiogenic effects of pazopanib could provide newer insights leading to the future development of drugs of the same mechanism with increased efficiency and reduced adverse effects.

An Archaeosome-Adjuvanted Vaccine and Checkpoint Inhibitor Therapy Combination Significantly Enhances Protection from Murine Melanoma

Archaeosomes constitute archaeal lipid vesicle vaccine adjuvants that evoke a strong CD8⁺ T cell response to antigenic cargo. Therapeutic treatment of murine B16-ovalbumin (B16-OVA) melanoma with archaeosome-OVA eliminates small subcutaneous solid tumors; however, they eventually resurge despite an increased frequency of circulating and tumor infiltrating OVA-CD8⁺ T cells. Herein, a number of different approaches were evaluated to improve responses, including dose number, interval, and the combination of vaccine with checkpoint inhibitors. Firstly, we found that tumor protection could not be enhanced by repetitive and/or delayed boosting to maximize the CD8⁺ T cell number and/or phenotype. The in vivo cytotoxicity of vaccine-induced OVA-CD8⁺ T cells was impaired in tumor-bearing mice. Additionally, tumor-infiltrating OVA-CD8⁺ T cells had an increased expression of programmed cell death protein-1 (PD-1) compared to other organ compartments, suggesting impaired function. Combination therapy of tumor-bearing mice with the vaccine archaeosome-OVA, and α-CTLA-4 administered concurrently as well as α-PD-1 and an α-PD-L1 antibody administered starting 9 days after tumor challenge given on a Q3Dx4 schedule (days 9, 12, 15 and 18), significantly enhanced survival. Following multi-combination therapy ~70% of mice had rapid tumor recession, with no detectable tumor mass after >80 days in comparison to a median survival of 17-22 days for untreated or experimental groups receiving single therapies. Overall, archaeosomes offer a powerful platform for delivering cancer antigens when used in combination with checkpoint inhibitor immunotherapies.

The Emerging Role of PD-1/PD-L1-Targeting Immunotherapy in the Treatment of Metastatic Urothelial Carcinoma

OBJECTIVE

To summarize and evaluate immunotherapy agents targeting programmed cell death protein-1 (PD-1) and programmed death ligand-1 (PD-L1) recently approved for the treatment of metastatic urothelial carcinomas (UC).

DATA SOURCES

A literature review was performed using PubMed (2012 to June 2017), the American Society of Clinical Oncology abstract databases (2012 to June 2017 Annual Meetings/symposia), and the America Association for Cancer Research symposia (2012 to June 2017). A search using clinicaltrials.gov was conducted to identify studies for atezolizumab, avelumab, durvalumab, nivolumab, and pembrolizumab.

STUDY SELECTION AND DATA EXTRACTION

English language phase I to III studies assessing PD-1 and PD-L1 in UC were incorporated.

DATA SYNTHESIS

Atezolizumab, avelumab, durvalumab, nivolumab, and pembrolizumab have demonstrated clinical efficacy with tolerable toxicities in patients with metastatic UC with disease progression following platinum-based chemotherapy. Anti-PD-1/PD-L1 therapies may provide overall survival advantage; these are currently being evaluated in ongoing phase 3 studies. Greater objective response rates seem to be observed in PD-L1-positive patients versus PD-L1-negative patients, but methodologies in this assessment differ among clinical trials. The identification of biomarkers that provide greater insight into patients who positively respond to PD-1/PD-L1 therapies are needed.

CONCLUSIONS

Treatment options for metastatic UC have expanded to include PD-1/PD-L1 therapies. These agents should be strongly considered as second-line therapy over single-agent chemotherapy for patients who fail or progress after platinum-based treatment.

Cancer stem cells and epithelial-mesenchymal transition in urothelial carcinoma: Possible pathways and potential therapeutic approaches

There is growing evidence of the presence of cancer stem cells in urothelial carcinoma. Cancer stem cells have the ability to self-renew and to differentiate into all cell types of the original heterogeneous tumor. A panel of diverse cancer stem cell markers might be suitable for simulation studies of urothelial cancer stem cells and for the development of optimized treatment protocols. The present review focuses on the advances in recognizing the markers of urothelial cancer stem cells and possible therapeutic targets. The commonly reported markers and pathways that were evaluated include CD44, CD133, ALDH1, SOX2 & SOX4, BMI1, EZH1, PD-L1, MAGE-A3, COX2/PGE2/STAT3, AR, and autophagy. Studies on the epithelial-mesenchymal transition-related pathways (Shh, Wnt/β-catenin, Notch, PI3K/Akt, TGF-β, miRNA) are also reviewed. Most of these markers were recognized through the expression patterns of cancer stem cell-rich side populations. Their regulative role in the development and differentiation of urothelial cancer stem cells was confirmed in vitro by functional analyses (e.g. cell migration, colony formation, sphere formation), and in vivo in xenograft experiments. Although a small number of these pathways are targeted by currently available drugs or drugs that are the currently being tested in clinical trials, a clear treatment approach has not been developed for most pathways. A greater understanding of the mechanisms that control the proliferation and differentiation of cancer stem cells is expected to lead to improvements in targeted therapy.

Systemic chemotherapy in muscle invasive and metastatic bladder cancer: present and future

Bladder cancer is the most frequent among the urothelial tumors, and it is responsible for about 2% of all cancer mortality worldwide. The mainstay of chemotherapy treatment, both for muscle-invasive and metastatic disease, is cisplatin-based regimens. In recent years, ground-breaking results have been achieved with immunotherapy, which have led to important breakthroughs in the bladder cancer treatment scenario, with the approval of several new agents. New insights derive from a greater characterization of the tumor genome, which could lead to developing new therapies, more personalized, in the near future.

A review on the evolution of PD-1/PD-L1 immunotherapy for bladder cancer: The future is now

The treatment of bladder cancer has evolved over time to encompass not only the traditional modalities of chemotherapy and surgery, but has been particularly impacted by the use of immunotherapy. The first immunotherapy was the live, attenuated bacterial Bacillus Calmette-Guérin vaccine, which has been the standard of care non-muscle-invasive bladder cancer since 1990. Modern immunotherapy has focused on inhibitors of checkpoint proteins, which are molecules that impede immune function, thereby allowing tumor cells to grow and proliferate unregulated. Several checkpoint targets (programmed death ligand-1 [PD-L1] programmed cell death protien-1 [PD-1], and cytotoxic T-lymphocyte associated protein 4 [CTLA4]) have received the most attention in the treatment of bladder cancer, and have inhibitor agents either approved or in late-stage development. This review describes the most recent data on agents that inhibit PD-L1, found on the surface of tumor cells, and PD-1 found on activated T and B cells and macrophages. Atezolizumab is the only member of this class currently approved for the treatment of bladder cancer, but nivolumab, pembrolizumab, durvalumab, and avelumab all have positive results for this indication, and approvals are anticipated in the near future. The checkpoint inhibitors offer an effective alternative for patients for whom previously there were few options for durable responses, including those who are ineligible for cisplatin-based regimens or who are at risk of significant toxicity. Research is ongoing to further categorize responses, define ideal patient populations, and investigate combinations of checkpoint inhibitors to address multiple pathways in immune system functioning.

Making urothelial carcinomas less immune to immunotherapy

The success of immune checkpoint inhibitors in advanced urothelial carcinoma provides patients with the prospect for durable objective responses. However, the majority of patients do not respond to immune checkpoint blockade. Several potential predictive biomarkers of response have been evaluated in hopes of better identifying likely responders, though each has been shown to have limitations. Going forward, development of reliable predictive biomarkers is imperative. Likewise, innovative treatment combination approaches to convert non-responders to responders are essential to continue making progress in the field.