Expression of PDL1 (B7-H1) Before and After Neoadjuvant Chemotherapy in Urothelial Carcinoma

PD-L1 Expression in High-Risk Non-Muscle-Invasive Bladder Cancer Is Influenced by Intravesical Bacillus Calmette-Guérin (BCG) Therapy

In the expanding landscape of immune checkpoint inhibitors (CPI) in high-risk (HR) non-muscle-invasive bladder cancer (NMIBC), the role of programmed death ligand 1 (PD-L1) as prognostic and predictive is increasingly significant. However, data evaluating its variability and susceptibility to Bacillus Calmette-Guérin (BCG) therapy in HR NMIBC patients is scarce. This retrospective study analyzed 126 HR NMIBC tissue samples from 63 patients (38× BCG-treated, 25× BCG-naïve) at two time points to assess PD-L1 expression using the 'combined positivity score' (CPS) with the 22C3 DAKO antibody method and correlated it with clinicopathological parameters. A CPS > 10 defined PD-L1 positivity. The impact of initial PD-L1 status and its change over time on time-to-recurrence, progression-free survival, and overall survival (TTR, PFS, OS) was analyzed using Kaplan-Meier and Cox proportional hazard models. BCG treatment significantly increased PD-L1 expression (5.31 vs. 0.22, p = 0.0423), with PD-L1 positive cases rising post-treatment in the BCG group and remaining unchanged in BCG-naïve patients. Multivariate analysis including T-stage, CIS, grading, tumor size, multifocality, age, and sex revealed a significant correlation between PD-L1 status change to positivity and improved TTR (p = 0.03). Our findings demonstrate a potential modulation of the PD-L1 status by an intravesical BCG therapy. However, its prognostic value appears limited.

Cost-effectiveness of immune checkpoint inhibitors in treating metastatic urothelial cancer

Objectives: Immune checkpoint inhibitor (ICI) is an important treatment option for metastatic urothelial carcinoma (mUC) patients. A lot of clinical evidence proved the survival benefits of ICI, but cost-effectiveness of the treatment remains unclear. This study evaluates the cost-effectiveness of the ICIs treatment in different sequences among mUC patients. Methods: We retrospectively analyzed mUC patients who had been treated at our hospital between January 2016 and December 2020. These patients received chemotherapy with or without ICI treatment (Pembrolizumab, Atezolizumab, Nivolumab, Durvalumab, or Avelumab). The patients were divided into three different groups: receiving chemotherapy alone, receiving a combination of first-line ICI and chemotherapy (ICI combination therapy), and receiving chemotherapy as the first-line treatment followed by second-line ICI therapy (Subsequent ICI therapy). The primary endpoint was cost per life day, while lifetime medical costs and overall survival were also evaluated. Results: The 74 enrolled patients had a median age of 67.0 years, with 62.2% being male. Of these patients, 23 had received chemotherapy only, while the remaining patients had received combined therapy with ICI in either first-line or as subsequent agents (37 patients had ever received atezolizumab, 18 pembrolizumab, 1 Durvalumab, 1 Nivolumab, and 1 Avelumab separately.). Fifty-five patients (74.3%, 55/74) received cisplatin amongst all the patients who underwent chemotherapy. Median overall survival was 27.5 months (95% CI, 5.2-49.9) in the first-line ICI combination therapy group, and 8.9 months (95% CI, 7.1-10.8) in the chemotherapy only. Median overall survival for the subsequent ICI therapy group was not reached. The median lifetime cost after metastatic UC diagnosis was USD 31,221. The subsequent ICI therapy group had significantly higher costs when compared with the ICI combination therapy group (155.8 USD per day, [IQR 99.0 to 220.5] v 97.8 USD per day, [IQR 60.8 to 159.19], p = 0.026). Higher insurance reimbursement expenses for the subsequent ICI therapy group were observed when compared with the ICI combination therapy group. Conclusion: Our real-world data suggests that first line use of ICI combined with chemotherapy demonstrates better cost-effectiveness and similar survival outcomes for mUC patients, when compared with subsequent ICI therapy after chemotherapy.

Significance of PD-L1 in Metastatic Urothelial Carcinoma Treated With Immune Checkpoint Inhibitors: A Systematic Review and Meta-Analysis

Importance

Immune checkpoint inhibitors (ICIs) have broadened the metastatic urothelial carcinoma (mUC) therapeutic scenario. The association of programmed death ligand 1 (PD-L1) with response and survival in patients treated with ICIs is still controversial.

Objectives

To evaluate the association of PD-L1 with response rate and overall survival among patients with mUC treated with ICIs.

Data Sources

PubMed, Embase, American Society of Clinical Oncology and European Society for Medical Oncology Meeting Libraries, and Web of Science were searched up to December 10, 2023.

Study Selection

Two authors independently screened the studies. Included studies were randomized and nonrandomized clinical trials enrolling patients with mUC receiving ICIs with available overall survival (OS), progression-free survival (PFS), or overall response rate (ORR) data, separated between patients with PD-L1-positive and -negative tumors.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed. Two reviewers independently extracted data. Fixed- or random-effects models were used depending on the heterogeneity among the studies.

Main Outcomes and Measures

Primary outcomes were odds ratios (ORs) for ORR and hazard ratios (HRs) for OS, comparing patients with PD-L1-positive tumors and patients with PD-L1-negative tumors. Secondary outcomes were the PFS HR between patients with PD-L1-positive and -negative tumors and OS HR between ICI arms and non-ICI arms of only randomized clinical trials.

Results

A total of 14 studies were selected, comprising 5271 patients treated with ICIs (2625 patients had PD-L1-positive tumors). The ORR was 13.8% to 78.6% in patients with PD-L1-positive tumors and 5.1% to 63.2% in patients with PD-L1-negative tumors, with an association between PD-L1 status and ORR favoring patients with PD-L1-positive tumors (OR, 1.94; 95% CI, 1.47-2.56; P < .001). Median OS ranged from 8.4 to 24.1 months in patients with PD-L1-positive tumors and from 6.0 to 19.1 months in patients with PD-L1-negative tumors. The pooled HR showed a significant reduction for patients with PD-L1-positive tumors compared with those with PD-L1-negative tumors in the risk of death (HR, 0.71; 95% CI, 0.57-0.89; P = .003) and risk of progression (HR, 0.55; 95% CI, 0.44-0.69; P < .001) when ICIs were administered. PD-L1 is not likely to be a predictive biomarker of ICI response.

Conclusions and Relevance

This systematic review and meta-analysis suggests that PD-L1 expression is associated with improved ORR, OS, and PFS for patients with mUC who receive ICIs, but it is unlikely to be useful as a predictive biomarker. Developing predictive biomarkers is essential to select patients most likely to benefit from ICIs and avoid toxic effects and financial burden with these agents.

Effect of Clinical Complete Remission Following Neoadjuvant Pembrolizumab or Chemotherapy in Bladder-Preservation Strategy in Patients with Muscle-Invasive Bladder Cancer Declining Definitive Local Therapy

This study aimed to evaluate the outcomes and identify the predictive factors of a bladder-preservation approach incorporating maximal transurethral resection of bladder tumor (TURBT) coupled with either pembrolizumab or chemotherapy for patients diagnosed with muscle-invasive bladder cancer (MIBC) who opted against definitive local therapy. We conducted a retrospective analysis on 53 MIBC (cT2-T3N0M0) patients who initially planned for neoadjuvant pembrolizumab or chemotherapy after maximal TURBT but later declined radical cystectomy and radiotherapy. Post-therapy clinical restaging and conservative bladder-preservation measures were employed. Clinical complete remission was defined as negative findings on cystoscopy with biopsy confirming the absence of malignancy if performed, negative urine cytology, and unremarkable cross-sectional imaging (either CT scan or MRI) following neoadjuvant therapy. Twenty-three patients received pembrolizumab, while thirty received chemotherapy. Our findings revealed that twenty-three (43.4%) patients achieved clinical complete response after neoadjuvant therapy. The complete remission rate was marginally higher in pembrolizumab group in comparison to chemotherapy group (52.1% vs. 36.7%, p = 0.26). After a median follow-up of 37.6 months, patients in the pembrolizumab group demonstrated a longer PFS (median, not reached vs. 20.2 months, p = 0.078) and OS (median, not reached vs. 26.8 months, p = 0.027) relative to those in chemotherapy group. Those achieving clinical complete remission post-neoadjuvant therapy also exhibited prolonged PFS (median, not reached vs. 10.2 months, p < 0.001) and OS (median, not reached vs. 24.4 months, p = 0.004). In the multivariate analysis, clinical complete remission subsequent to neoadjuvant therapy was independently associated with superior PFS and OS. In conclusion, bladder preservation emerges as a viable therapeutic strategy for a carefully selected cohort of MIBC patients without definitive local therapy, especially those achieving clinical complete remission following neoadjuvant treatment. For patients unfit for chemotherapy, pembrolizumab offers a promising alternative treatment option.

Impact of glucose metabolism on PD-L1 expression in sorafenib-resistant hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer-related mortality worldwide. Programmed cell death ligand-1 (PD-L1) is an immune checkpoint protein that binds to programmed cell death-1 (PD-1), which is expressed in activated T cells and other immune cells and has been employed in cancer therapy, including HCC. Recently, PD-L1 overexpression has been documented in treatment-resistant cancer cells. Sorafenib is a multikinase inhibitor and the only FDA-approved treatment for advanced HCC. However, several patients exhibit resistance to sorafenib during treatment. This study aimed to assess the effect of glucose deprivation on PD-L1 expression in HCC cells. We used PD-L1-overexpressing HepG2 cells and IFN-γ-treated SK-Hep1 cells to explore the impact of glycolysis on PD-L1 expression. To validate the correlation between PD-L1 expression and glycolysis, we analyzed data from The Cancer Genome Atlas (TCGA) and used immunostaining for HCC tissue analysis. Furthermore, to modulate PD-L1 expression, we treated HepG2, SK-Hep1, and sorafenib-resistant SK-Hep1R cells with rapamycin. Here, we found that glucose deprivation reduced PD-L1 expression in HCC cells. Additionally, TCGA data and immunostaining analyses confirmed a positive correlation between the expression of hexokinase II (HK2), which plays a key role in glucose metabolism, and PD-L1. Notably, rapamycin treatment  decreased the expression of PD-L1 and HK2 in both high PD-L1-expressing HCC cells and sorafenib-resistant cells. Our results suggest that the modulation of PD-L1 expression by glucose deprivation may represent a strategy to overcome PD-L1 upregulation in patients with sorafenib-resistant HCC.

Autophagy as a Target for Non-Immune Intrinsic Functions of Programmed Cell Death-Ligand 1 in Cancer

Autophagy is a catabolic process that is essential to the maintenance of homeostasis through the cellular recycling of damaged organelles or misfolded proteins, which sustains energy balance. Additionally, autophagy plays a dual role in modulating the development and progression of cancer and inducing a survival strategy in tumoral cells. Programmed cell death-ligand 1 (PD-L1) modulates the immune response and is responsible for maintaining self-tolerance. Because tumor cells exploit the PD-L1-PD-1 interaction to subvert the immune response, immunotherapy has been developed based on the use of PD-L1-blocking antibodies. Recent evidence has suggested a bidirectional regulation between autophagy and PD-L1 molecule expression in tumor cells. Moreover, the research into the intrinsic properties of PD-L1 has highlighted new functions that are advantageous to tumor cells. The relationship between autophagy and PD-L1 is complex and still not fully understood; its effects can be context-dependent and might differ between tumoral cells. This review refines our understanding of the non-immune intrinsic functions of PD-L1 and its potential influence on autophagy, how these could allow the survival of tumor cells, and what this means for the efficacy of anti-PD-L1 therapeutic strategies.

[Practical aspects of PD-L1 assessment in the treatment of urothelial carcinoma: Consensus of the uropathology group of the SEAP]

The recent addition of novel immunotherapy drugs for the treatment of urothelial carcinoma makes it necessary the establishment of criteria to harmonize the immunohistochemical assessment of PD-L1, both as a prognostic factor and for the selection of patients to be treated. In this scenario, a group of uropathologists from the Spanish Society of Pathological Anatomy, together with a medical oncologist as an external collaborator subspecialized in uro-oncology, have prepared this document of recommendations based on the available evidence. During PD-L1 assessment it is especially relevant the selection of the sample, its processing, the immunohistochemical platform and antibody used, and the algorithm applied in the interpretation of results. All these aspects must be indicated in the results report, which should be easily interpretable in a context of rapid evolution of immunological therapies.

The evolving role of checkpoint inhibitors in the treatment of urothelial carcinoma

The most prevalent pathological subtype of bladder and upper urinary tract malignancy is urothelial carcinoma (UC). Traditional therapies mainly include surgical resection, chemotherapy and radiotherapy. Checkpoint inhibitors, which are monoclonal antibodies developed to specifically target immune checkpoint molecules, have recently emerged as potential treatment options for UC patients, especially those targeting the programmed cell death protein 1 (PD-1) and its ligand (PD-L1). However, anti-PD-1/PD-L1 therapy does not work for a considerable number of UC patients. Current antitumour immunotherapy research hotspots include seeking biomarkers that might predict therapeutic effects and exploring novel immune checkpoint molecules crucial for the antitumour immune response. Hence, we will recapitulate the latest preclinical and clinical trials of 5 PD-1/PD-L1 inhibitors, 1 cytotoxic T-lymphocyte-associated protein 4 inhibitor and combination therapies for UC treatment, including combined immunotherapy and immunotherapy with chemotherapy or radiotherapy. We will also summarize other potential immune checkpoint molecules found in ongoing UC studies. Moreover, we will highlight the role of biomarkers linked with the oncological efficacy of anti-PD-1/PD-L1 immunotherapy and address the mechanisms of immunotherapy drug resistance in UC, with the hope of providing more systematic guidance for its application and development.

Neoadjuvant immunochemotherapy in the treatment of nonmetastatic muscle-invasive bladder cancer: a systematic review

Introduction: Multiple trials are currently studying the additional effect of immunotherapy on neoadjuvant chemotherapy (NAC) in nonmetastatic muscle-invasive bladder cancer. Methods: We performed a systematic review of the literature that summarizes all ongoing trials, with their results when available. Results: From an initial 269 trials identified, 17 were included. Pathological response and pathological complete response rates of the immunotherapy + NAC combination in the cisplatin-eligible population varied between 56.6-75% and 34.0-66.7%, respectively. Two studies published their results in the cisplatin-ineligible population, with pathological complete response rates of 18 and 45.2%. Conclusion: Neoadjuvant immunochemotherapy in platinum-eligible patients results in response rates higher than those reported for NAC alone. Strong preliminary results are still lacking in the platinum-ineligible population.

Identification of New Prognostic Markers and Therapeutic Targets for Non-Muscle Invasive Bladder Cancer: HER2 as a Potential Target Antigen

Bacillus Calmette–Guérin (BCG) is the gold standard adjuvant treatment for non-muscle-invasive bladder cancer (NMIBC). However, given the current global shortage of BCG, new treatments are needed. We evaluated tumor microenvironment markers as potential BCG alternatives for NMIBC treatment. Programmed death-ligand 1, human epidermal growth factor receptor-2 (HER2), programmed cell death-1 (PD1), CD8, and Ki67 levels were measured in treatment-naïve NMIBC and MIBC patients (pTa, pT1, and pT2 stages). Univariate and multivariate Cox proportional hazard models were used to determine the impact of these markers and other clinicopathological factors on survival, recurrence, and progression. EP263, IM142, PD1, and Ki67 levels were the highest in the T2 stage, followed by the T1 and Ta stages. HER2 and IM263 expressions were higher in the T1 and T2 stages than in the Ta stage. In NMIBC, the significant prognostic factors for recurrence-free survival were adjuvant therapy, tumor grade, and HER2 positivity, whereas those for progression-free survival included age, T-stage, and IM263. Age, T-stage, EP263, PD1, CD8, and Ki67 levels were significant factors associated with overall survival. IM263 and HER2 are potential biomarkers for progression and recurrence, respectively. Therefore, we propose HER2 as a potential target antigen for intravesical therapeutics as a BCG alternative.

Extracellular Vesicle-Mediated IL-1 Signaling in Response to Doxorubicin Activates PD-L1 Expression in Osteosarcoma Models

The expression of programmed cell death ligand 1 (PD-L1) in tumors is associated with tumor cell escape from T-cell cytotoxicity, and is considered a crucial effector in chemoresistance and tumor relapse. Although PD-L1 induction has been observed in patients after chemotherapy treatment, the mechanism by which the drug activates PD-L1 expression remains elusive. Here, we identified the extracellular vesicles (EVs) as a molecular mediator that determines the effect of doxorubicin on PD-L1 expression in osteosarcoma models. Mechanistically, doxorubicin dependently stimulates the release of extracellular vesicles, which mediate autocrine/paracrine signals in osteosarcoma cells. The recipient cells were stimulated by these EVs and acquired the ability to promote the expression of inflammatory cytokines interleukin (IL)-1β and IL-6. In response to doxorubicin, IL-1β, but not IL-6, allowed- osteosarcoma cells to promote the expression of PD-L1, and the elimination of IL-1β/IL-1 receptor signaling with IL-1 receptor antagonist reduced PD-L1 expression. Together, these findings provided insights into the role of EV release in response to chemotherapy that mediates PD-L1 expression via the IL-1 signaling pathway, and suggested that the combination of a drug targeting IL-1 or PD-L1 with chemotherapy could be an effective treatment option for osteosarcoma patients.

Checkpoint Inhibition in Bladder Cancer: Clinical Expectations, Current Evidence, and Proposal of Future Strategies Based on a Tumor-Specific Immunobiological Approach

Simple Summary

In contrast with other strategies, immunotherapy is a treatment aimed at empowering the patient’s immune system in order to increase immunity and the response against cancer. Recently, a new class of drugs, immune checkpoint inhibitors, has shown potential in increasing treatment chances for patients with bladder cancers, improving their survival. However, predicting the response to immune checkpoint inhibition is important, since only a group of patients develop a good response. Biomarkers to predict the response to checkpoint inhibition must identify tumors’ and patients’ specific profiles. This study reviews the current knowledge on this most relevant clinical topic, focusing on bladder cancer, going from basic science to ongoing clinical trials and available clinical evidence. Finally, a critical analysis of published data is provided, and an original panel of biomarkers, able to select the right patients for treatments, based on patient-specific immune profiling, is proposed.

Abstract

In contrast with other strategies, immunotherapy is the only treatment aimed at empowering the immune system to increase the response against tumor growth. Immunotherapy has a role in the treatment of bladder cancer (BC) due to these tumors’ high tumor mutational burden (TMB) and mostly prominent immune infiltrate. The therapy or combination has to be adjusted to the tumor’s immunobiology. Recently, a new class of immunotherapeutic agents, immune checkpoint inhibitors (ICI), has shown potential in increasing treatment chances for patients with genitourinary cancers, improving their oncological outcomes. The clinical efficacy of ICI has been shown in both the first-line treatment of cisplatin-ineligible patients, with programmed death ligand 1 (PD-L1)-positive tumors (atezolizumab, pembrolizumab), and in second-line settings, for progression after platinum-based chemotherapy (atezolizumab, pembrolizumab, and nivolumab for FDA and EMA; durvalumab and avelumab for FDA alone). Predicting the response to ICI is important since only a subset of patients undergoing ICI therapy develop a concrete and lasting response. Most of the patients require a different therapy or therapy combination to achieve tumor control. The cancer immunity cycle provides a conceptual framework to assist therapy selection. Biomarkers to predict response to ICI must identify where the cancer immunity cycle is disrupted. We reviewed the current knowledge on ICI treatment in BC, going from basic science to current data and available clinical evidence. Secondly, a critical analysis of published data is provided, and an original panel of biomarkers able to predict response to ICI treatment, based on tumor-specific immune profiling, is proposed.

Cancer immunotherapy: it's time to better predict patients' response

In less than a decade, half a dozen immune checkpoint inhibitors have been approved and are currently revolutionising the treatment of many cancer (sub)types. With the clinical evaluation of novel delivery approaches (e.g. oncolytic viruses, cancer vaccines, natural killer cell-mediated cytotoxicity) and combination therapies (e.g. chemo/radio-immunotherapy) as well as the emergence of novel promising targets (e.g. TIGIT, LAG-3, TIM-3), the 'immunotherapy tsunami' is not about to end anytime soon. However, this enthusiasm in the field is somewhat tempered by both the relatively low percentage (<15%) of patients who display an effective anti-cancer immune response and the inability to accurately identify them. Recently, several existing or acquired features/parameters have been shown to impact the efficacy of immune checkpoint inhibitors. In the present review, we critically discuss current knowledge regarding predictive biomarkers for checkpoint inhibitor-based immunotherapy, highlight the missing/unclear links and emphasise the importance of characterising each neoplasm and its microenvironment in order to better guide the course of treatment.

Prognostic Role of Programmed Death Ligand-1 on Tumor-Infiltrating Immune Cells in "High-Risk" Patients Following Radical Cystectomy: A Retrospective Cohort Study

Purpose

The aim of this study is to investigate the prognostic role of programmed death ligand-1 (PD-L1) on tumor-infiltrating immune cells (TIICs) in patients after radical cystectomy (RC) for bladder cancer (BCa).

Materials and Methods

We retrospectively reviewed 92 “high-risk” (≥pT3a and/or pN+) patients who underwent RC for BCa, without adjuvant chemotherapy (AC), between April 2014 and December 2019. PD-L1 on TIICs was measured only using the VENTANA (SP-142) immunohistochemistry assay. Patients were categorized into three groups based to the percentage of the tumor area covered by PD-L1 on TIICs: IC0 (<1%), IC1 (≥1% and <5%), and IC2/3 (≥5%). Positive PD-L1 was defined as IC2/3 (≥5%). Kaplan–Meier survival analysis was used to illustrate recurrence-free survival (RFS), and Cox proportional hazard models were used to identify predictive factors of tumor recurrence.

Results

Within the cohort, the proportions of PD-L1 IC0, IC1, and IC2/3 were 21.7%, 23.9%, and 54.4%, respectively. At follow-up (mean 31.3 months), tumor recurrence was identified in 49 patients (53.3%). Using multivariable analysis, tumor stage (pT4; P=0.005), positive lymph nodes (P=0.021), and positive PD-L1 on TIICs (P=0.010) were independent predictors of tumor recurrence. The 2- and 3-year RFS rates were 67.7% and 64.2% in negative PD-L1 on TIICs, while 27.8% and 22.3% in positive PD-L1 on TIICs, respectively.

Conclusions

Positive PD-L1 on TIICs was significantly associated with poorer RFS in “high-risk” patients after RC without AC. Our results support the use of adjuvant immunotherapy in “high-risk” patients with positive PD-L1 on TIICs after RC.

Prognostic Function of Programmed Cell Death-Ligand 1 in Esophageal Squamous Cell Carcinoma Patients Without Preoperative Therapy: A Systematic Review and Meta-Analysis

Background

Studies investigating the correlation between the expression of programmed cell death-ligand 1 (PD-L1) and prognosis in patients with esophageal squamous cell carcinoma (ESCC) not receiving preoperative therapy have increased significantly, but conclusions remain inconclusive. Therefore, this study aimed to determine the association between clinical outcomes and expression of PD-L1 in ESCC patients without preoperative therapy.

Methods

We conducted a comprehensive literature search using four databases up to May 2020. Quality assessment was carried out according to the Newcastle-Ottawa Quality Assessment Scale (NOS). Hazard ratios (HRs) were used to analyze the association between PD-L1 expression with prognosis. Furthermore, we evaluated the correlation between PD-L1 and clinicopathological characteristics using odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Twenty studies (19 publications) comprising 3,677 patients were included in this meta-analysis. We found that the expression of PD-L1 was not related to overall survival (OS, HR: 1.16, 95% CI: 0.94-1.42, p = 0.16) or disease-free survival (DFS, HR: 0.85, 95% CI: 0.66-1.10, p = 0.21) in ESCC. Furthermore, although PD-L1 expression was not significantly associated with sex, degree of differentiation, TNM stage, T stage, lymph node status, smoking, or alcohol use, the merged OR demonstrated that the expression of PD-L1 was higher in older patients compared to younger patients (OR: 1.40, 95% CI: 1.07-1.83, p = 0.01). No obvious publication bias was observed.

Conclusions

Our present study illustrated that PD-L1 expression was not related to poor prognosis of ESCC patients not receiving preoperative therapy, albeit the association only showed a tendency for statistical significance. Notably, PD-L1 expression showed a significant association with age. This meta-analysis had several limitations; therefore, our results need to be verified through further large-scale and prospective studies.

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.

Impact of prior intravesical bacillus Calmette-Guerin therapy on the effectiveness of pembrolizumab for patients with metastatic urothelial carcinoma

OBJECTIVE

The aim of this study was to determine whether a history of treatment for non-muscle invasive bladder cancer (NMIBC), including intravesical bacillus Calmette-Guerin (BCG) therapy, affects the treatment outcomes of pembrolizumab in patients with metastatic, chemo-resistant urothelial carcinoma (UC).

MATERIALS AND METHODS

The clinicopathological data of 755 patients with metastatic, chemo-resistant UC who received pembrolizumab were retrospectively reviewed. Best overall response and overall survival (OS) from the initiation of pembrolizumab were analyzed with regard to the history of NMIBC treatment and BCG usage using propensity score matching (PSM).

RESULTS

A total of 155 (20.5%) patients had a history of NMIBC treatment, of which 97 (12.8%) had received intravesical BCG therapy. When compared to patients without a NMIBC history (median 10.0 months), the OS from the initiation of pembrolizumab for patients with a NMIBC history (13.3 months, HR [95% CI] 0.79 [0.62-1.02], P = 0.073), those with a NMIBC history and BCG (12.1 months, HR 0.87 [0.64-1.17], P = 0.356), or those with a NMIBC history but not BCG (14.5 months, HR 0.68 [0.45-1.12], P = 0.061) were not significantly different. This tendency was robust after 1:1 or 1:2 PSMs. The objective response rate (ORR, 24.5% vs. 31.0%, P = 0.222) and disease control rate (DCR, 56.1% vs. 52.1%, P = 0.501) of the 155 patients with an NMIBC history did not differ from those of 155 matched patients without an NMIBC history. Among those with an NMIBC history, the prior use of BCG did not affect OS (with vs. without BCG, 12.1 vs. 14.5 months, HR 1.29 [0.80-2.09], P = 0.295), ORR (24.5% vs. 34.0%, P = 0.298) or DCR (57.1% vs. 56.0%, P = 0.908). The ORR in BCG-treated patients was significantly lower than that in those without a NMIBC history (19.8% vs. 33.3%, P = 0.042), whereas DCR between the 2 groups did not differ significantly (55.8% vs. 54.4%, P = 0.855).

CONCLUSIONS

Our risk-adjusted analyses revealed that a history of prior NMIBC treatment, including intravesical BCG therapy, did not affect the treatment outcomes of pembrolizumab in metastatic UC patients.

Gemcitabine Plus Nab-Paclitaxel Induces PD-L1 mRNA Expression in Plasma-Derived Microvesicles in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a non-immunogenic tumor poorly responsive to immune checkpoint inhibitors. This study investigates the effect of 5-fluorouracil (5-FU), irinotecan, and oxaliplatin (FOLFIRINOX), and gemcitabine plus nab-paclitaxel (GEMnPAC) regimens on PD-L1 mRNA expression in plasma-derived microvesicles (MVs) in 50 PDAC patients. Plasma was collected before starting chemotherapy and after 3 months of treatment. mRNA was extracted from MVs, and PD-L1 expression was measured by digital droplet PCR. Twenty-eight patients were PD-L1 positive in MVs at baseline, of which 18 were in the GEMnPAC cohort and 10 in the FOLFIRINOX one. The amount of PD-L1 expression in MVs increased from baseline to 3 months of treatment in patients receiving GEMnPAC (median value 0.002 vs. 0.005; p = 0.01) compared to those treated with FOLFIRINOX (median 0.003 vs. 0.004; p = 0.97). The increase in PD-L1 mRNA expression in MVs was not related to tumor response (PR + SD: p = 0.08; PD: p = 0.28). Our findings demonstrate that GEMnPAC can increase PD-L1 mRNA expression in patient-derived circulating MVs, providing a rationale for testing the efficacy of this regimen in sequential or simultaneous combinations with immunotherapy in PDAC patients.

Prognostic Impact of PD-1 on Tumor-Infiltrating Lymphocytes in 433 Resected Esophageal Cancers

BACKGROUND

Immune checkpoint inhibitors targeting the programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway have demonstrated antitumor effects in patients with various malignancies, including esophageal cancer. Thus, a better understanding of local immunity in esophageal cancer is crucial for improving treatment and clinical outcomes.

METHODS

We evaluated PD-1 expression on tumor-infiltrating lymphocytes (TILs), as well as PD-L1 expression on cancer cells, by immunohistochemistry and immunofluorescence using a nonbiased database of 433 curatively resected esophageal cancers. With the idea of application as liquid biopsy, PD-1 expression status on peripheral lymphocytes was evaluated by flow cytometry.

RESULTS

The cutoff value of PD-1 expression was the median PD-1 count. Compared with cases of low PD-1 expression (n = 219), cases with high levels of PD-1 expression (n = 213) showed significantly worse overall survival (log-rank P = .0017). The prognostic effect of PD-1 differed according to the preoperative treatment status (P for interaction = .040); PD-1 expression was associated with high overall mortality among patients without preoperative therapy, while no such association was present among those with preoperative treatment. A stratification based on PD-1 and PD-L1 status was also significantly associated with overall survival (log-rank P = .0005). PD-1 expression on TILs was significantly associated with that on peripheral lymphocytes (P < .0001).

CONCLUSIONS

PD-1 expression on TILs was associated with an unfavorable clinical outcome in esophageal cancer, supporting its role as a prognostic biomarker. The combination of PD-1 and PD-L1 expression enabled further classification of patients according to clinical outcome.

The Dichotomous Role of Bone Marrow Derived Cells in the Chemotherapy-Treated Tumor Microenvironment

Bone marrow derived cells (BMDCs) play a wide variety of pro- and anti-tumorigenic roles in the tumor microenvironment (TME) and in the metastatic process. In response to chemotherapy, the anti-tumorigenic function of BMDCs can be enhanced due to chemotherapy-induced immunogenic cell death. However, in recent years, a growing body of evidence suggests that chemotherapy or other anti-cancer drugs can also facilitate a pro-tumorigenic function in BMDCs. This includes elevated angiogenesis, tumor cell proliferation and pro-tumorigenic immune modulation, ultimately contributing to therapy resistance. Such effects do not only contribute to the re-growth of primary tumors but can also support metastasis. Thus, the delicate balance of BMDC activities in the TME is violated following tumor perturbation, further requiring a better understanding of the complex crosstalk between tumor cells and BMDCs. In this review, we discuss the different types of BMDCs that reside in the TME and their activities in tumors following chemotherapy, with a major focus on their pro-tumorigenic role. We also cover aspects of rationally designed combination treatments that target or manipulate specific BMDC types to improve therapy outcomes.

PD-L1 expression in tumor-infiltrating lymphocytes (TILs) as an independent predictor of prognosis in patients with pN0 bladder cancer undergoing radical cystectomy

OBJECTIVES

Checkpoint inhibitors have led to a paradigm shift in urothelial carcinoma (UC) treatment. However, the relationship between PD-L1 expression status and oncological outcomes in UC patients remains uncertain. Here, we investigated the prognostic value of PD-L1 expression status in patients with UC of the bladder (UCB) who underwent radical cystectomy (RC).

MATERIALS AND METHODS

We retrospectively analyzed pathological specimens from 97 UCB patients treated with RC from 1990 to 2015 at Kitasato University Hospital. Immunohistochemical staining using SP263 was performed to evaluate PD-L1 expression in tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs). Kaplan-Meier plots and proportional Cox hazard ratios were examined to assess the relationship between PD-L1 expression and clinicopathological parameters and survival outcomes.

RESULTS

Of the 97 specimens, 19.5% contained PD-L1-positive TCs, and 35.0% contained PD-L1-positive TILs. Regarding clinicopathological factors, PD-L1-positive TCs and TILs were significantly associated with high-grade tumors (TCs, P = 0.01; TILs, P = 0.003). Kaplan-Meier analyses showed that PD-L1-positive TCs were not correlated with survival rates. However, PD-L1-positive TILs were significantly associated with better recurrence-free survival (RFS; P = 0.03) and better cancer-specific survival (CSS; P = 0.02). Univariate analysis, but not multivariate analysis, CSS indicated that PD-L1-positive TILs were significant predictors of patient prognoses. Multivariate analysis showed that PD-L1-positive TILs independently predicted CSS in patients without lymph node metastasis (pN0).

CONCLUSION

Positive PD-L1 expression is associated with high-grade tumors. PD-L1-positive TILs are independent predictors of favorable survival outcomes in surgically resected UCB patients at stage pN0.

ENERGIZE: a Phase III study of neoadjuvant chemotherapy alone or with nivolumab with/without linrodostat mesylate for muscle-invasive bladder cancer

Immune checkpoint inhibitors have revolutionized the treatment of patients with metastatic urothelial carcinoma. In cisplatin-eligible muscle-invasive bladder cancer (MIBC), cisplatin-based neoadjuvant chemotherapy (NAC) before radical cystectomy improves overall survival. Tumor PD-L1 expression increases in MIBC after NAC, suggesting potential synergy in combining PD1/PD-L1 inhibitors with NAC. IDO1 is overexpressed in bladder cancer and is associated with poor outcomes. Linrodostat mesylate (BMS-986205) – a selective, potent, oral IDO1 inhibitor – combined with nivolumab has demonstrated safety and preliminary evidence of clinical activity in metastatic urothelial carcinoma. Here, we discuss the rationale and trial design of the ENERGIZE, a Phase III trial investigating the efficacy of NAC in combination with nivolumab with or without linrodostat followed by postsurgery nivolumab or nivolumab with linrodostat in cisplatin-eligible patients with MIBC. Clinical trial registration number: NCT03661320

The Value of Programmed Death Ligand 1 Expression in Cancer Patients Treated with Neoadjuvant Chemotherapy

Programmed death ligand 1 (PD-L1) is an inhibitory molecule expressed by cancer cells to supress T-cell activity and escape anti-tumour immunity. The role of PD-L1 in cancer has been studied extensively as it is considered an important immune checkpoint against immune over-activation through its interaction with Programmed death receptor 1 (PD-1) expressed on activated lymphocytes. PD-L1 expression was found to be enhanced by chemotherapy through different proliferation pathways. However, the predictive and prognostic value for PD-L1 expression in cancer patients treated with neoadjuvant chemotherapy (NAC) is not yet established. This review focused on the potential effects of chemotherapy on PD-L1 expression and the role of PD-L1 as a prognostic and predictive marker in NAC-treated cancer patients. In addition, the potential use of this marker in clinical practice is discussed.

Programmed Cell Death Ligand 1 in Breast Cancer: Technical Aspects, Prognostic Implications, and Predictive Value

In the light of recent advances in the immunotherapy field for breast cancer (BC) treatment, especially in the triple-negative subtype, the identification of reliable biomarkers capable of improving patient selection is paramount, because only a portion of patients seem to derive benefit from this appealing treatment strategy. In this context, the role of programmed cell death ligand 1 (PD-L1) as a potential prognostic and/or predictive biomarker has been intensively explored, with controversial results. The aim of the present review is to collect available evidence on the biological relevance and clinical utility of PD-L1 expression in BC, with particular emphasis on technical aspects, prognostic implications, and predictive value of this promising biomarker. IMPLICATIONS FOR PRACTICE: In the light of the promising results coming from trials of immune checkpoint inhibitors for breast cancer treatment, the potential predictive and/or prognostic role of programmed cell death ligand 1 (PD-L1) in breast cancer has gained increasing interest. This review provides clinicians with an overview of the available clinical evidence regarding PD-L1 as a biomarker in breast cancer, focusing on both data with a possible direct impact on clinic and methodological pitfalls that need to be addressed in order to optimize PD-L1 implementation as a clinically useful tool for breast cancer management.

[Immunotherapy for locally advanced and metastasized bladder cancer]

Urothelial carcinoma of the bladder is difficult to treat in advanced and metastatic stages. Several factors play a role: age, multimorbidity including impaired renal function and neuropathy make access to life-prolonging chemotherapy impossible in many cases. Improvements of response rates and overall survival in the second-line setting are not much different compared to best supportive care. However, the therapeutic landscape has changed dramatically during the last 2 years. Immunotherapies represented by checkpoint inhibitors have showed positive trial outcomes and have been approved by EMA (European Medicines Agency). Both in second-line therapy after platinum-based chemotherapy and in first-line therapy in unfit patients, these drugs can be used. New concepts with combinations of immunotherapeutic compounds are currently being examined in various trials. If we follow the data of other malignancies (melanoma and non-small cell lung cancer), the future looks optimistic.

Synergistic effect of meta-tetra(hydroxyphenyl)chlorin-based photodynamic therapy followed by cisplatin on malignant Hep-2 cells

Purpose

Tumor drug resistance limits the response to chemotherapy. Interestingly, sequential combination therapy enhances the anticancer efficacy of drugs like cisplatin (CDDP) via synergistic effects. We assayed the synergistic effects of combined photodynamic therapy programmed death receptor-ligand 1 (PDT) and chemotherapy in malignant Hep-2 cells.

Methods

In the cultured Hep-2 cells, meta-tetra(hydroxyphenyl)chlorin (m-THPC) and CDDP were administered separately or in combination. The cellular viability and apoptosis were assessed, accompanied by measurement of the expression of Bax, Bcl-2, ATG-7, and LC3 (LC3-I and LC3-II). Additionally, nuclear chromatin changes, drug retention, and PD-L1 expression were further investigated following different treatments.

Results

The sequential treatment significantly diminished cell viability and induced cell apoptosis, in consistency with the usage of single therapeutic strategies, as reflected by an increase in Bax expression and decrease of Bcl-2 expression. Moreover, ATG-7 and LC3-II/LC3-I ratio were reduced after administration of the sequential treatment. Synergetic effect of nuclear chromatin configuration, negative effects of cellular drug retention, and a decrease in PD-L1 expression were observed following the sequential treatment.

Conclusion

The application of sequential treatment of PDT in combination with chemotherapy offers a promising therapeutic option for cancer treatment, by regulating the PD-L1 expression, autophagy, and non-mitochondrial pathways.

The emerging role of immunotherapy in advanced urothelial cancers

PURPOSE OF REVIEW

Recent Food and Drug Administration (FDA) approval of five new immune checkpoint inhibitors for the treatment of metastatic urothelial cancer represents the first major treatment breakthrough for this disease since the introduction of combination chemotherapy over 30 years ago. This review examines the recent clinical trials leading to FDA approval of these agents, the current challenges facing immunotherapy and areas that require further research.

RECENT FINDINGS

The programmed death 1 receptor (PD-1) and its ligand programmed death ligand-1 (PD-L1) are important negative regulators of immune activity, preventing destruction of normal tissues and autoimmunity. Aggressive bladder cancer cells express aberrantly high levels of PD-L1, hijacking the normal immune-regulatory pathway to evade detection and destruction by the immune system. Blockade of the PD-1/PD-L1 axis with immune checkpoint inhibitors augments the immune system's ability to eradicate bladder cancer with impressive safety and tolerability profiles.

SUMMARY

Recent clinical trials demonstrate that patients with metastatic urothelial carcinoma are responsive to immune checkpoint inhibitor therapy. Optimal treatment regimens are still under development, but activity has been demonstrated in both the first and second-line setting for metastatic disease.

Chemotherapeutic Treatments Increase PD-L1 Expression in Esophageal Squamous Cell Carcinoma through EGFR/ERK Activation

The current study reveals the clinicopathological association of PD-L1 in Hong Kong esophageal squamous cell carcinoma (ESCC) patients and the differential regulation of PD-L1 by standard first-line chemotherapy in ESCC. Immunohistochemical analysis of tissue microarray data from 84 Hong Kong ESCC patients shows that PD-L1 was expressed in 21% of the tumors. Positive PD-L1 staining was significantly associated with later disease stage (stages III and IV) (P value = .0379) and lymph node metastasis (P value = .0466) in the Hong Kong cohort. Furthermore, PD-L1 expression was significantly induced in ESCC cell lines after standard chemotherapy treatments, along with EGFR and ERK activation in both in vitro studies and the in vivo esophageal orthotopic model. The endogenous expression of PD-L1 was reduced by treatment with an EGFR inhibitor (erlotinib) or by the knockdown of EGFR. Moreover, the upregulation of PD-L1 by chemotherapy was also attenuated by the treatment with erlotinib and a MAPK/MEK inhibitor (AZD6244), suggesting that PD-L1 is regulated by the EGFR/ERK pathway in ESCC. The regulation of PD-L1 by the EGFR pathway was further supported by the correlation of PD-L1 and EGFR expression observed in the commercially available tissue microarray set (P value = .028). Taken together, the current study was the first to demonstrate the upregulation of PD-L1 by chemotherapy in ESCC and its regulation through the EGFR/ERK pathway. The results suggest the potential usefulness of combined conventional chemotherapy together with anti-PD-L1 immunotherapy to achieve better treatment outcome.

Combining Immunotherapy with Radiotherapy for the Treatment of Genitourinary Malignancies

CONTEXT

Immunotherapy drugs, particularly checkpoint inhibitors, have recently been approved by the Food and Drug Administration for various malignancies. Preclinical and early clinical data show that combining these agents with radiotherapy may produce an even more potent antitumor effect in the treatment of cancer.

OBJECTIVE

To describe the rationale, available data, and emerging data on the use of combined immunotherapy and radiation therapy in the setting of genitourinary (GU) malignancies.

EVIDENCE ACQUISITION

We performed a search of primary studies from PubMed/Medline that included combinations of the search terms "radiation therapy," "radiotherapy," "abscopal effect," "immunotherapy," "combined," and "combination."

EVIDENCE SYNTHESIS

Preclinical and clinical data support both immune-stimulating and immune-suppressing effects of radiotherapy. Preclinical and clinical studies investigating the combination of radiotherapy with immunotherapy, primarily in the setting of non-GU malignancies, have suggested efficacy and tolerability. Early randomized trials combining radiotherapy and immunotherapy have demonstrated success in lung cancer. Although a trial investigating combined immunotherapy and radiotherapy use for prostate cancer did not clearly improve survival, trials are ongoing in multiple GU malignancies to identify synergy between immunotherapy and radiotherapy. Several practical and technical questions remain about the optimal combination of radiotherapy and immunotherapy.

CONCLUSIONS

Preclinical and clinical trials show that the combination of the immunotherapy and radiation therapy has the potential to provide a synergistic effect in treating cancer, including GU malignancies, although more work is needed to uncover the mechanism and determine the optimal delivery of this treatment.

PATIENT SUMMARY

This paper reviews evidence that immunotherapy drugs can be given together with radiation therapy to improve outcomes in cancers of the genitourinary tract. We find promising initial results and raise important questions that need to be answered before this type of treatment can be utilized successfully.

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

The treatment of advanced metastatic urothelial carcinoma has recently evolved with the approval of five checkpoint inhibitors. In the second-line setting, in patients who have progressed on cisplatin-based chemotherapy, pembrolizumab, atezolizumab, durvalumab, nivolumab and avelumab are United States Food and Drug Administration (FDA) approved. In cisplatin-ineligible patients, atezolizumab and pembrolizumab are the FDA-approved checkpoint inhibitors. Here we describe the updated clinical efficacy of these checkpoint inhibitors in the treatment of advanced urothelial carcinoma and then suggest how they can be sequenced in the context of available chemotherapeutic options. For cisplatin-eligible patients, platinum-based chemotherapy remains the standard first-line treatment. For patients progressing on platinum-based therapy, phase III trials have been performed comparing pembrolizumab and atezolizumab separately with standard chemotherapy, and results favor the use of pembrolizumab.

Effect of neoadjuvant chemotherapy on the immune microenvironment in non-small cell lung carcinomas as determined by multiplex immunofluorescence and image analysis approaches

Background

The clinical efficacy observed with inhibitors of programed cell death 1/programed cell death ligand 1 (PD-L1/PD-1) in cancer therapy has prompted studies to characterize the immune response in several tumor types, including lung cancer. However, the immunological profile of non–small cell lung carcinoma (NSCLC) treated with neoadjuvant chemotherapy (NCT) is not yet fully characterized, and it may be therapeutically important. The aim of this retrospective study was to characterize and quantify PD-L1/PD-1 expression and tumor-associated immune cells (TAICs) in surgically resected NSCLCs from patients who received NCT or did not receive NCT (non-NCT).

Methods

We analyzed immune markers in formalin-fixed, paraffin-embedded tumor tissues resected from 112 patients with stage II/III NSCLC, including 61 non-NCT (adenocarcinoma [ADC] = 33; squamous cell carcinoma [SCC] = 28) and 51 NCT (ADC = 31; SCC = 20). We used multiplex immunofluorescence to identify and quantify immune markers grouped into two 6-antibody panels: panel 1 included AE1/AE3, PD-L1, CD3, CD4, CD8, and CD68; panel 2 included AE1/AE3, PD1, granzyme B, FOXP3, CD45RO, and CD57.

Results

PD-L1 expression was higher (> overall median) in NCT cases (median, 19.53%) than in non-NCT cases (median, 1.55%; P = 0.022). Overall, density of TAICs was higher in NCT-NSCLCs than in non-NCT-NSCLCs. Densities of CD3+ cells in the tumor epithelial compartment were higher in NCT-ADCs and NCT-SCCs than in non-NCT-ADCs and non-NCT-SCCs (P = 0.043). Compared with non-NCT-SCCs, NCT-SCCs showed significantly higher densities of CD3 + CD4+ (P = 0.019) and PD-1+ (P < 0.001) cells in the tumor epithelial compartment. Density of CD68+ tumor-associated macrophages (TAMs) was higher in NCT-NSCLCs than in non-NCT-NSCLCs and was significantly higher in NCT-SCCs than in non-NCT-SCCs. In NCT-NSCLCs, higher levels of epithelial T lymphocytes (CD3 + CD4+) and epithelial and stromal TAMs (CD68+) were associated with better outcome in univariate and multivariate analyses.

Conclusions

NCT-NSCLCs exhibited higher levels of PD-L1 expression and T-cell subset regulation than non-NCT-NSCLCs, suggesting that NCT activates specific immune response mechanisms in lung cancer. These results suggest the need for clinical trials and translational studies of combined chemotherapy and immunotherapy prior to surgical resection of locally advanced NSCLC.

Electronic supplementary material

The online version of this article (10.1186/s40425-018-0368-0) contains supplementary material, which is available to authorized users.

Immunotherapy: a new treatment paradigm in bladder cancer

PURPOSE OF REVIEW

T-cell checkpoint blockade has become a dynamic immunotherapy for bladder cancer. In 2016, atezolizumab, an immune checkpoint inhibitor, became the first new drug approved in metastatic urothelial carcinoma (mUC) in over 30 years. In 2017, nivolumab was also approved for the same indication. This overview of checkpoint inhibitors in clinical trials focuses on novel immunotherapy combinations, predictive biomarkers including mutational load and neoantigen identification, and an evaluation of the future of bladder cancer immunotherapy.

RECENT FINDINGS

Programed cell death protein 1/programed death-ligand 1 (PD-1/PD-L1) checkpoint inhibitors have achieved durable clinical responses in a subset of previously treated and treatment-naïve patients with mUC. The combination of PD-1 and cytotoxic T-lymphocyte antigen 4 (CTLA-4) has successfully improved response rates in multiple malignancies, and combination studies are underway in many tumor types, including bladder cancer, combining T-cell checkpoint blockade with other checkpoint agents and immunomodulatory therapies. Strong tumor responses to checkpoint blockade have been reported to be positively associated with expression of PD-L1 on tumor and tumor-infiltrating immune cells and with increased mutation-associated neoantigen load, which may lead to the development of predictive biomarkers.

SUMMARY

Recent clinical evidence suggests that mUC is susceptible to T-cell checkpoint blockade. A global effort is underway to achieve higher response rates and more durable remissions, accelerate the development of immunotherapies, employ combination therapies, and test novel immune targets.

Avelumab, an Anti-Programmed Death-Ligand 1 Antibody, In Patients With Refractory Metastatic Urothelial Carcinoma: Results From a Multicenter, Phase Ib Study

Purpose

We assessed the safety and antitumor activity of avelumab, a fully human anti–programmed death-ligand 1 (PD-L1) IgG1 antibody, in patients with refractory metastatic urothelial carcinoma.

Methods

In this phase Ib, multicenter, expansion cohort, patients with urothelial carcinoma progressing after platinum-based chemotherapy and unselected for PD-L1 expression received avelumab 10 mg/kg intravenously every 2 weeks. The primary objectives were safety and tolerability. Secondary objectives included confirmed objective response rate (Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1), progression-free survival, overall survival (OS), and PD-L1–associated clinical activity. PD-L1 positivity was defined as expression by immunohistochemistry on ≥ 5% of tumor cells.

Results

Forty-four patients were treated with avelumab and followed for a median of 16.5 months (interquartile range, 15.8 to 16.7 months). The data cutoff was March 19, 2016. The most frequent treatment-related adverse events of any grade were fatigue/asthenia (31.8%), infusion-related reaction (20.5%), and nausea (11.4%). Grades 3 to 4 treatment-related adverse events occurred in three patients (6.8%) and included asthenia, AST elevation, creatine phosphokinase elevation, and decreased appetite. The confirmed objective response rate by independent central review was 18.2% (95% CI, 8.2% to 32.7%; five complete responses and three partial responses). The median duration of response was not reached (95% CI, 12.1 weeks to not estimable), and responses were ongoing in six patients (75.0%), including four of five complete responses. Seven of eight responding patients had PD-L1–positive tumors. The median progression-free survival was 11.6 weeks (95% CI, 6.1 to 17.4 weeks); the median OS was 13.7 months (95% CI, 8.5 months to not estimable), with a 12-month OS rate of 54.3% (95% CI, 37.9% to 68.1%).

Conclusion

Avelumab was well tolerated and associated with durable responses and prolonged survival in patients with refractory metastatic UC.

Programmed Death-ligand 1 Expression in Upper Tract Urothelial Carcinoma

BACKGROUND

Urothelial carcinoma (UC) is the most common malignancy of the urinary tract. Upper tract (renal pelvis and ureter) urothelial carcinomas (UTUC) account for approximately 5% of UCs but a significant subset are invasive and associated with poor clinical outcomes.

OBJECTIVE

To evaluate programmed death-ligand 1 (PD-L1) expression in UTUC.

DESIGN, SETTING, AND PARTICIPANTS

UTUC cases from 1997-2016 were retrospectively identified from the surgical pathology database at a single large academic institution. The cohort included 149 cases: 27 low-grade and 24 high-grade pathologic T (pT)a, 29 pT1, 23 pT2, 38 pT3, and eight pT4. PD-L1 immunohistochemistry (IHC) was performed on representative whole tumor sections using anti-PD-L1 primary antibody clone 5H1.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

PD-L1 expression was evaluated using a previously established cut-off for positivity (≥ 5% membranous staining). Association between PD-L1 IHC expression and clinicopathologic parameters was examined with Fisher's exact test; the effect of PD-L1 expression on cancer-specific mortality was assessed using the Cox proportional hazard model.

RESULTS AND LIMITATIONS

Approximately one-third (32.7%) of invasive primary UTUC and 23.5% of all primary UTUC (invasive and noninvasive tumors) demonstrated positive PD-L1 expression. Positive PD-L1 expression was associated with high histologic grade, high pathologic stage, and angiolymphatic invasion. Cancer-specific survival was not significantly associated with positive PD-L1 expression using a 5% cut-off. Study limitations include the retrospective nature and the fact that PD-L1 expression by IHC is an imperfect surrogate for response to therapy.

CONCLUSIONS

Positive PD-L1 expression in approximately one-third of primary invasive UTUC and association with high-risk clinicopathologic features provide a rational basis for further investigation of PD-L1-based immunotherapeutics in these patients.

PATIENT SUMMARY

Upper tract urothelial carcinoma is often associated with poor clinical outcome. While current treatment options for advanced upper tract urothelial carcinoma are limited, programmed death-ligand 1 positivity in approximately one-third of invasive tumors provides a rational basis for further investigation of programmed death-ligand 1-based immunotherapeutics in these patients.

5-Fluorouracil upregulates cell surface B7-H1 (PD-L1) expression in gastrointestinal cancers

Background

Resistance to chemotherapy is a major obstacle in the effective treatment of cancer patients. B7-homolog 1, also known as programmed death ligand-1 (PD-L1), is an immunoregulatory protein that is overexpressed in several human cancers. Interaction of B7-H1 with programmed death 1 (PD-1) prevents T-cell activation and proliferation, sequestering the T-cell receptor from the cell membrane, inducing T-cell apoptosis, thereby leading to cancer immunoresistance. B7-H1 upregulation contributes to chemoresistance in several types of cancer, but little is known with respect to changes associated with 5-fluorouracil (5-FU) or gastrointestinal cancers.

Methods

HCT 116 p53^+/+, HCT 116 p53^−/− colorectal cancer (CRC) and OE33 esophageal adenocarcinoma (EAC) cells were treated with increasing doses of 5-FU (0.5 uM, 5 uM, 50 uM, 500 uM) or interferon gamma (IFN-γ, 10 ng/mL) in culture for 24 h and B7-H1 expression was quantified using flow cytometry and western blot analysis. We also evaluated B7-H1 expression, by immunohistochemistry, in tissue collected prior to and following neoadjuvant therapy in 10 EAC patients.

Results

B7-H1 expression in human HCT 116 p53^+/+ and HCT 116 p53^−/− CRC cells lines, while low at baseline, can be induced by treatment with 5-FU. OE33 baseline B7-H1 expression exceeded CRC cell maximal expression and could be further increased in a dose dependent manner following 5-FU treatment in the absence of immune cells. We further demonstrate tumor B7-H1 expression in esophageal adenocarcinoma patient-derived pre-treatment biopsies. While B7-H1 expression was not enhanced in post-treatment esophagectomy specimens, this may be due to the limits of immunohistochemical quantification.

Conclusions

B7-H1/PD-L1 expression can be increased following treatment with 5-FU in gastrointestinal cancer cell lines, suggesting alternative mechanisms to classic immune-mediated upregulation. This suggests that combining 5-FU treatment with PD-1/B7-H1 blockade may improve treatment in patients with gastrointestinal adenocarcinoma.

Perspectives for immunotherapy in endocrine cancer

The fight against cancer has seen major breakthroughs in recent years. More than a decade ago, tyrosine kinase inhibitors targeting constitutively activated signaling cascades within the tumor inaugurated a new era of oncological therapy. Recently, immunotherapy with immune checkpoint inhibitors has started to revolutionize the treatment of several malignancies, most notably malignant melanoma, leading to the renaissance and the long-awaited breakthrough of immunooncology. This review provides an overview of the basis of immunotherapy from its initial concepts of anti-tumor immunity and cell-based therapy to the development of immune checkpoint inhibitors and discusses published studies and the perspectives of immunooncology for the treatment of endocrine malignancies.

Evaluation of PD-L1 Expression in Tumor Tissue of Patients with Lung Carcinoma and Correlation with Clinical and Demographic Data

Lung cancer is the leading world cause of cancer-related death, in both genders, and smoking is the main etiological factor. The discovery of immune checkpoints corroborates the hypothesis that ligands presented in tumors modulate the mechanisms of carcinogenesis and the immune activity of tumor microenvironment. Among the most studied coregulatory molecules, PD-1 (programmed cell death 1) and its ligand PD-L1 (programmed cell death 1 ligand 1) are noteworthy. The present study aims to enhance the understanding of the tumor microenvironment of lung cancer patients who underwent surgery, by means of analysis of PD-L1 expression in tumor cells and in intratumoral immune cells (IICs). It was found that PD-L1 expression was more frequent in tumor cells than in IICs. Collective analysis by Tissue Microarray Assay (TMA) for PD-L1 expression in tumor cells and IICs did not reproduce the findings for separate individual analysis of tumor tissues. Patients with past history of smoking were more likely to express PD-L1 in tumor cells than those who never smoked. Patients with past history of smoking were less likely to have PD-L1 positive IICs compared to those who had never smoked. The immunohistochemical expression of PD-L1 in tumor cells and IICs did not correlate with survival.

Frequent PD-L1 expression in primary and metastatic penile squamous cell carcinoma: potential opportunities for immunotherapeutic approaches

BACKGROUND

Despite aggressive multimodal therapy, locally advanced and/or metastatic penile squamous cell carcinoma (SqCC) is associated with significant morbidity and mortality, indicating a need for new therapeutic options. Given the emerging clinical utility of immunotherapeutics, we sought to assess the incidence and potential clinical significance of PD-L1 expression in penile SqCC.

PATIENTS AND METHODS

Using an anti-PD-L1 primary antibody (clone 5H1), immunohistochemistry was carried out on whole tumor sections from 37 patients with penile SqCC treated at our institution between 2005 and 2013. PD-L1-positive tumors were defined as those with membranous staining in ≥5% of tumor cells. Association between PD-L1 expression and clinicopathologic parameters was examined using Fisher's exact test. Correlation between PD-L1 expression in primary tumors and matched metastases was assessed using the Spearman rank correlation coefficient (ρ). The difference in cancer-specific mortality between PD-L1-positive and -negative groups was examined using the log-rank test.

RESULTS

Twenty-three (62.2%) of 37 primary tumors were positive for PD-L1 expression, and there was strong positive correlation of PD-L1 expression in primary and metastatic samples (ρ = 0.72; 0.032 < P < 0.036). Primary tumor PD-L1 expression was significantly associated with usual type histology (P = 0.040) and regional lymph node metastasis (P = 0.024), as well as decreased cancer-specific survival (P = 0.011).

CONCLUSIONS

The majority of primary penile SqCC tumors express PD-L1, which is associated with high-risk clinicopathologic features and poor clinical outcome. These data provide a rational basis for further investigation of anti-PD-1 and anti-PD-L1 immunotherapeutics in patients with advanced penile SqCC.