The genetic and cellular alterations that define cancer provide the immune system with the means to generate T cell responses that recognize and eradicate cancer cells. However, elimination of cancer ...by T cells is only one step in the Cancer-Immunity Cycle, which manages the delicate balance between the recognition of nonself and the prevention of autoimmunity. Identification of cancer cell T cell inhibitory signals, including PD-L1, has prompted the development of a new class of cancer immunotherapy that specifically hinders immune effector inhibition, reinvigorating and potentially expanding preexisting anticancer immune responses. The presence of suppressive factors in the tumor microenvironment may explain the limited activity observed with previous immune-based therapies and why these therapies may be more effective in combination with agents that target other steps of the cycle. Emerging clinical data suggest that cancer immunotherapy is likely to become a key part of the clinical management of cancer.
Immunotherapy is proving to be an effective therapeutic approach in a variety of cancers. But despite the clinical success of antibodies against the immune regulators CTLA4 and PD-L1/PD-1, only a ...subset of people exhibit durable responses, suggesting that a broader view of cancer immunity is required. Immunity is influenced by a complex set of tumour, host and environmental factors that govern the strength and timing of the anticancer response. Clinical studies are beginning to define these factors as immune profiles that can predict responses to immunotherapy. In the context of the cancer-immunity cycle, such factors combine to represent the inherent immunological status - or 'cancer-immune set point' - of an individual.
Cancer immunotherapy is a validated and critically important approach for treating patients with cancer. Given the vast research and clinical investigation efforts dedicated to advancing both ...endogenous and synthetic immunotherapy approaches, there is a need to focus on crucial questions and define roadblocks to the basic understanding and clinical progress. Here, we define ten key challenges facing cancer immunotherapy, which range from lack of confidence in translating pre-clinical findings to identifying optimal combinations of immune-based therapies for any given patient. Addressing these challenges will require the combined efforts of basic researchers and clinicians, and the focusing of resources to accelerate understanding of the complex interactions between cancer and the immune system and the development of improved treatment options for patients with cancer.
In recent years, cancer immunotherapy has become a pillar in the treatment of cancer. Hegde and Chen discuss the top ten challenges facing this field, including the opportunity to optimize both synthetic and endogenous immune approaches and to target different immune suppressive mechanisms specific for each patient with cancer.
The discovery of vascular endothelial-derived growth factor (VEGF) has revolutionized our understanding of vasculogenesis and angiogenesis during development and physiological homeostasis. Over a ...short span of two decades, our understanding of the molecular mechanisms by which VEGF coordinates neurovascular homeostasis has become more sophisticated. The central role of VEGF in the pathogenesis of diverse cancers and blinding eye diseases has also become evident. Elucidation of the molecular regulation of VEGF and the transformative development of multiple therapeutic pathways targeting VEGF directly or indirectly is a powerful case study of how fundamental research can guide innovation and translation. It is also an elegant example of how agnostic discovery and can transform our understanding of human disease. This review will highlight critical nodal points in VEGF biology, including recent developments in immunotherapy for cancer and multitarget approaches in neovascular eye disease.
Since it discovery two decades ago, VEGF has emerged as an important modulator of vascular biology, with therapeutics targeting VEGF signaling being central to the treatment of cancer and eye disease.
Cancer immunotherapy (CIT) has transformed cancer treatment. In particular, immunotherapies targeting the programmed death ligand 1 (PD-L1)/programmed death 1 pathway have demonstrated durable ...clinical benefit in some patients. However, CIT combinations may create a more favorable environment in which to maximize the potential of the immune system to eliminate cancer. Here we describe 3 key mechanisms related to vascular endothelial growth factor (VEGF)-mediated immunosuppression: inhibition of dendritic cell maturation, reduction of T-cell tumor infiltration, and promotion of inhibitory cells in the tumor microenvironment; supporting data are also described. In addition, we discuss immunomodulatory properties observed within tumors following bevacizumab treatment. Combining anti-PD-L1 and anti-VEGF therapies has shown synergy and positive outcomes in phases I to III studies, particularly in settings where high VEGF levels are known to play an important role in tumor growth. We also review data from key studies supporting combination of bevacizumab and CIT, with a focus on PD-L1/programmed death 1 inhibitors.
The cancer-immunity cycle provides a framework to understand the series of events that generate anti-cancer immune responses. It emphasizes the iterative nature of the response where the killing of ...tumor cells by T cells initiates subsequent rounds of antigen presentation and T cell stimulation, maintaining active immunity and adapting it to tumor evolution. Any step of the cycle can become rate-limiting, rendering the immune system unable to control tumor growth. Here, we update the cancer-immunity cycle based on the remarkable progress of the past decade. Understanding the mechanism of checkpoint inhibition has evolved, as has our view of dendritic cells in sustaining anti-tumor immunity. We additionally account for the role of the tumor microenvironment in facilitating, not just suppressing, the anti-cancer response, and discuss the importance of considering a tumor’s immunological phenotype, the “immunotype”. While these new insights add some complexity to the cycle, they also provide new targets for research and therapeutic intervention.
The cancer-immunity cycle provides a framework to understand the events that generate anti-cancer immune responses. Mellman, Chen, Powles, and Turley consider the last 10 years of research in cancer immunology and immunotherapy and review the progress in understanding each step of the cancer-immunity cycle, identifying challenges and opportunities for the next decade.
Different antibodies can bind to the same targets on the surface of immune cells with opposite biologic effects. These effects—agonism, antagonism, or partial agonism—are so poorly understood that ...drug developers must screen antibodies for relevant desired characteristics. In this issue of Immunity, Lippert et al. define molecular mechanisms that dictate antibody behavior, ushering in an era of directed antibody design.
Different antibodies can bind to the same targets on the surface of immune cells with opposite biologic effects. These effects—agonism, antagonism, or partial agonism—are so poorly understood that drug developers must screen antibodies for relevant desired characteristics. In this issue of Immunity, Lippert et al. define molecular mechanisms that dictate antibody behavior, ushering in an era of directed antibody design.
Summary Background Outcomes are poor for patients with previously treated, advanced or metastatic non-small-cell lung cancer (NSCLC). The anti-programmed death ligand 1 (PD-L1) antibody atezolizumab ...is clinically active against cancer, including NSCLC, especially cancers expressing PD-L1 on tumour cells, tumour-infiltrating immune cells, or both. We assessed efficacy and safety of atezolizumab versus docetaxel in previously treated NSCLC, analysed by PD-L1 expression levels on tumour cells and tumour-infiltrating immune cells and in the intention-to-treat population. Methods In this open-label, phase 2 randomised controlled trial, patients with NSCLC who progressed on post-platinum chemotherapy were recruited in 61 academic medical centres and community oncology practices across 13 countries in Europe and North America. Key inclusion criteria were Eastern Cooperative Oncology Group performance status 0 or 1, measurable disease by Response Evaluation Criteria In Solid Tumors version 1.1 (RECIST v1.1), and adequate haematological and end-organ function. Patients were stratified by PD-L1 tumour-infiltrating immune cell status, histology, and previous lines of therapy, and randomly assigned (1:1) by permuted block randomisation (with a block size of four) using an interactive voice or web system to receive intravenous atezolizumab 1200 mg or docetaxel 75 mg/m2 once every 3 weeks. Baseline PD-L1 expression was scored by immunohistochemistry in tumour cells (as percentage of PD-L1-expressing tumour cells TC3≥50%, TC2≥5% and <50%, TC1≥1% and <5%, and TC0<1%) and tumour-infiltrating immune cells (as percentage of tumour area: IC3≥10%, IC2≥5% and <10%, IC1≥1% and <5%, and IC0<1%). The primary endpoint was overall survival in the intention-to-treat population and PD-L1 subgroups at 173 deaths. Biomarkers were assessed in an exploratory analysis. We assessed safety in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov , number NCT01903993. Findings Patients were enrolled between Aug 5, 2013, and March 31, 2014. 144 patients were randomly allocated to the atezolizumab group, and 143 to the docetaxel group. 142 patients received at least one dose of atezolizumab and 135 received docetaxel. Overall survival in the intention-to-treat population was 12·6 months (95% CI 9·7–16·4) for atezolizumab versus 9·7 months (8·6–12·0) for docetaxel (hazard ratio HR 0·73 95% CI 0·53–0·99; p=0·04). Increasing improvement in overall survival was associated with increasing PD-L1 expression (TC3 or IC3 HR 0·49 0·22–1·07; p=0·068, TC2/3 or IC2/3 HR 0·54 0·33–0·89; p=0·014, TC1/2/3 or IC1/2/3 HR 0·59 0·40–0·85; p=0·005, TC0 and IC0 HR 1·04 0·62–1·75; p=0·871). In our exploratory analysis, patients with pre-existing immunity, defined by high T-effector–interferon-γ-associated gene expression, had improved overall survival with atezolizumab. 11 (8%) patients in the atezolizumab group discontinued because of adverse events versus 30 (22%) patients in the docetaxel group. 16 (11%) patients in the atezolizumab group versus 52 (39%) patients in the docetaxel group had treatment-related grade 3–4 adverse events, and one (<1%) patient in the atezolizumab group versus three (2%) patients in the docetaxel group died from a treatment-related adverse event. Interpretation Atezolizumab significantly improved survival compared with docetaxel in patients with previously treated NSCLC. Improvement correlated with PD-L1 immunohistochemistry expression on tumour cells and tumour-infiltrating immune cells, suggesting that PD-L1 expression is predictive for atezolizumab benefit. Atezolizumab was well tolerated, with a safety profile distinct from chemotherapy. Funding F Hoffmann-La Roche/Genentech Inc.
We present SpanBERT, a pre-training method that is designed to better represent and predict spans of text. Our approach extends BERT by (1) masking contiguous random spans, rather than random tokens, ...and (2) training the span boundary representations to predict the entire content of the masked span, without relying on the individual token representations within it. SpanBERT consistently outperforms BERT and our better-tuned baselines, with substantial gains on span selection tasks such as question answering and coreference resolution. In particular, with the same training data and model size as BERT
, our single model obtains 94.6% and 88.7% F1 on SQuAD 1.1 and 2.0 respectively. We also achieve a new state of the art on the OntoNotes coreference resolution task (79.6% F1), strong performance on the TACRED relation extraction benchmark, and even gains on GLUE.
The aim of T-cell-based immune therapy for cancer has been to generate durable clinical benefit for patients. Following a generation of therapies that largely showed minimal activity, substantial ...toxicity, and no biomarkers to identify which patients benefit from treatment, early studies are showing signs that programmed death-ligand 1 (PD-L1) and programmed death-1 (PD-1) inhibitors are highly active. Preclinical and early data from clinical studies suggest that targeting this pathway can induce durable clinical responses in patients in a variety of tumor types, including lung and colon cancer. Furthermore, correlations with tumor PD-L1 expression may enable selection of patients most likely to benefit from treatment. The emerging data not only offer the hope of better cancer therapy but also provide evidence that changes our understanding of how the host immune system interacts with human cancer.
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