A pilot study of CTLA-4 blockade after cancer vaccine failure in patients with advanced malignancy

Current Approaches of Immune Checkpoint Therapy in Chronic Lymphocytic Leukemia

OPINION STATEMENT

Increasing understanding of the complex interaction between leukemic and immune cells, which is responsible for tumor progression and immune evasion, has paved the way for the development of novel immunotherapy approaches in chronic lymphocytic leukemia (CLL). One of the well-known immune escape mechanisms of tumor cells is the up-regulation of immune checkpoint molecules. In recent years, targeting immune checkpoint receptors is the most clinically effective immunotherapeutic strategy for cancer treatment. In this regard, various immune checkpoint blockade (ICB) drugs are currently been investigating for their potential effects on improving anti-tumor immune response and clinical efficacy in the hematological malignancies; however, their effectiveness in patients with CLL has shown less remarkable success, and ongoing research is focused on identifying strategies to enhance the efficacy of ICB in CLL.

Polymersome-mediated cytosolic delivery of cyclic dinucleotide STING agonist enhances tumor immunotherapy

Cyclic dinucleotides (CDNs) as stimulator of interferon genes (STING) agonists capable of inducing strong antitumor innate immune response are highly promising for tumor immunotherapy. The efficacy of these CDNs is, however, reduced greatly by their fast clearance, poor cell uptake and inefficient cytosolic transportation. Here, we report that reduction-responsive biodegradable chimaeric polymersomes (CPs) markedly enhance tumor retention and cytosolic delivery of a synthetic CDN, ADU-S100, and bolster STING pathway activation in the tumor microenvironment and tumor draining lymph nodes, giving significantly better tumor repression and survival of B16F10 melanoma-bearing mice compared with free CDN control. The superiority of CPs-mediated CDN delivery is further verified in combination therapy with low-dose fractionated radiation, which brings about clearly stronger and longer-term immunotherapeutic effects and protection against tumor re-challenge. The development of nano-STING agonists that are able to overcome the delivery barriers of CDNs represents an effective strategy to potentiate cancer immunotherapy.

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Chimaeric polymersomes (CPs) show efficient loading of STING agonist cyclic dinucleotide.

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Intratumoral injection of CPs-CDN gives notable tumor accumulation and cytosolic delivery of STING agonist.

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CPs-CDN activate STING pathway in tumor microenvironment and tumor draining lymph node, giving significant tumor repression and survival of melanoma mice.

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CPs-CDN combined with low-dose fractionated X ray irradiation led to further boosted immunotherapy with 3/7 cured mice.

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Nano-STING agonists can overcome the delivery barriers of CDNs and potentiate durable cancer immunotherapy.

Safety and Efficacy of Immune Checkpoint Inhibitors in Children and Young Adults with Haematological Malignancies: Review and Future Perspectives

Despite the marked improvement in overall survival rates of paediatric patients with haematological malignancies that has been achieved during the last decades, there is still a pressing need for novel therapeutic approaches for the subset of patients with relapsed or refractory disease. Immune checkpoint inhibitors aim to induce potent anti-tumour immune responses by targeted blockade of inhibitory receptors and have shown great promise in preclinical models and studies in the adult population. However, paediatric malignancies present unique features and so far, experience with these agents remains limited. In the current review we present an overview of efficacy and safety data from case reports, case series and clinical trials employing the use of immune checkpoint inhibitors in children, adolescents and young adults with haematological malignancies. We also discuss new possibilities involving novel targets and combination treatments and provide a summary of the currently registered clinical trials.

Engaging the Innate and Adaptive Antitumor Immune Response in Lymphoma

Immunotherapy has emerged as a powerful therapeutic strategy for many malignancies, including lymphoma. As in solid tumors, early clinical trials have revealed that immunotherapy is not equally efficacious across all lymphoma subtypes. For example, immune checkpoint inhibition has a higher overall response rate and leads to more durable outcomes in Hodgkin lymphomas compared to non-Hodgkin lymphomas. These observations, combined with a growing understanding of tumor biology, have implicated the tumor microenvironment as a major determinant of treatment response and prognosis. Interactions between lymphoma cells and their microenvironment facilitate several mechanisms that impair the antitumor immune response, including loss of major histocompatibility complexes, expression of immunosuppressive ligands, secretion of immunosuppressive cytokines, and the recruitment, expansion, and skewing of suppressive cell populations. Accordingly, treatments to overcome these barriers are being rapidly developed and translated into clinical trials. This review will discuss the mechanisms of immune evasion, current avenues for optimizing the antitumor immune response, clinical successes and failures of lymphoma immunotherapy, and outstanding hurdles that remain to be addressed.

Predicting Responses to Checkpoint Inhibitors in Lymphoma: Are We Up to the Standards of Solid Tumors?

Treatment of cancer has transformed with the introduction of checkpoint inhibitors. However, the majority of solid tumor patients do not respond to checkpoint blockade. In contrast, the response rate to programmed cell death 1 (PD-1) blockade in relapsed/refractory classical Hodgkin lymphoma (cHL) is 65% to 84% which is the highest among all cancers. Currently, checkpoint inhibitors are only approved for cHL and primary mediastinal B-cell lymphoma as the responses to single-agent checkpoint blockade in other hematologic malignancies is disappointingly low. Various established biomarkers such as programmed cell death 1 ligand 1 (PD-L1) protein surface expression, mismatch repair (MMR) status, and tumor mutational burden (TMB) are routinely used in clinical decision-making in solid tumors. In this review, we will explore these biomarkers in the context of hematologic malignancies. We review characteristic 9p24.1 structural alteration in cHL and primary mediastinal B-cell lymphoma (PMBCL) as a basis for response to PD-1 inhibition, as well as the role of antigen presentation pathways. We also explore the reported frequencies of MMR deficiency in various hematologic malignancies and investigate TMB as a predictive marker.

Overcoming the Hurdles of Autologous T-Cell-Based Therapies in B-Cell Non-Hodgkin Lymphoma

Simple Summary

The activity of novel therapies that utilize patient’s own T-cells to induce remission of B-cell non-Hodgkin lymphoma (B-NHL), including chronic lymphocytic leukemia (CLL), is still suboptimal. In this review, we summarize the clinical efficacy of T-cell-based therapies in B-NHL and provide a biologic rationale for the observed (lack of) responses. We describe and compare the acquired T-cell dysfunctions that occur in the different subtypes of B-NHL. Furthermore, we discuss new insights that could enhance the efficacy of T-cell-based therapies for B-NHL and CLL.

Abstract

The next frontier towards a cure for B-cell non-Hodgkin lymphomas (B-NHL) is autologous cellular immunotherapy such as immune checkpoint blockade (ICB), bispecific antibodies (BsAbs) and chimeric antigen receptor (CAR) T-cells. While highly successful in various solid malignancies and in aggressive B-cell leukemia, this clinical success is often not matched in B-NHL. T-cell subset skewing, exhaustion, expansion of regulatory T-cell subsets, or other yet to be defined mechanisms may underlie the lack of efficacy of these treatment modalities. In this review, a systematic overview of results from clinical trials is given and is accompanied by reported data on T-cell dysfunction. From these results, we distill the underlying pathways that might be responsible for the observed differences in clinical responses towards autologous T-cell-based cellular immunotherapy modalities between diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), mantle cell lymphoma (MCL), and marginal zone lymphoma (MZL). By integration of the clinical and biological findings, we postulate strategies that might enhance the efficacy of autologous-based cellular immunotherapy for the treatment of B-NHL.

Manipulation of the Immune System for Cancer Defeat: A Focus on the T Cell Inhibitory Checkpoint Molecules

The immune system actively counteracts the tumorigenesis process; a breakout of the immune system function, or its ability to recognize transformed cells, can favor cancer development. Cancer becomes able to escape from immune system control by using multiple mechanisms, which are only in part known at a cellular and molecular level. Among these mechanisms, in the last decade, the role played by the so-called "inhibitory immune checkpoints" is emerging as pivotal in preventing the tumor attack by the immune system. Physiologically, the inhibitory immune checkpoints work to maintain the self-tolerance and attenuate the tissue injury caused by pathogenic infections. Cancer cell exploits such immune-inhibitory molecules to contrast the immune intervention and induce tumor tolerance. Molecular agents that target these checkpoints represent the new frontier for cancer treatment. Despite the heterogeneity and multiplicity of molecular alterations among the tumors, the immune checkpoint targeted therapy has been shown to be helpful in selected and even histologically different types of cancer, and are currently being adopted against an increasing variety of tumors. The most frequently used is the moAb-based immunotherapy that targets the Programmed Cell Death 1 protein (PD-1), the PD-1 Ligand (PD-L1) or the cytotoxic T lymphocyte antigen-4 (CTLA4). However, new therapeutic approaches are currently in development, along with the discovery of new immune checkpoints exploited by the cancer cell. This article aims to review the inhibitory checkpoints, which are known up to now, along with the mechanisms of cancer immunoediting. An outline of the immune checkpoint targeting approaches, also including combined immunotherapies and the existing trials, is also provided. Notwithstanding the great efforts devoted by researchers in the field of biomarkers of response, to date, no validated FDA-approved immunological biomarkers exist for cancer patients. We highlight relevant studies on predictive biomarkers and attempt to discuss the challenges in this field, due to the complex and largely unknown dynamic mechanisms that drive the tumor immune tolerance.

CD47: the next checkpoint target for cancer immunotherapy

Cancer immunotherapy using checkpoint blockade has brought about a paradigm shift in the treatment of advanced-stage cancers. Unfortunately, not all patients benefit from these therapies, paving the way for other immune checkpoints to be targeted. CD47, a 'marker-of-self' protein that is overexpressed broadly across tumor types, is emerging as a novel potent macrophage immune checkpoint for cancer immunotherapy. Recently, CD47 blockade by Hu5F9-G4 has shown promise combined with Rituximab in non-Hodgkin's lymphoma. Here we review the complex structure and various physiological functions of CD47 and their implications in cancer biology. Further, this review considers future directions and challenges in advancing this promising target platform to widespread therapeutic use.

Therapeutic Development of Immune Checkpoint Inhibitors

Immune checkpoint blockade (ICB) has been proven to be an effective strategy for enhancing the effector activity of anti-tumor T cells, and checkpoint blockers targeting CTLA-4, PD-1, and PD-L1 have displayed strong and durable clinical responses in certain cancer patients. The new hope brought by ICB therapy has led to the boost in therapeutic development of ICBs in recent years. Nonetheless, the therapeutic efficacy of ICBs varies substantially among cancer types and patients, and only a proportion of cancer patients could benefit from ICBs. The emerging targets and molecules for enhancing anticancer immunity may bring additional therapeutic opportunities for cancer patients. The current challenges in the ICB therapy have been discussed, aimed to provide further strategies for maximizing the efficacy of ICB therapy.

Dawn of Monitoring Regulatory T Cells in (Pre-)clinical Studies: Their Relevance Is Slowly Recognised

Regulatory T cells (Tregs) have a prominent role in the control of immune homeostasis. Pharmacological impact on their activity or balance with effector T cells could contribute to (impaired) clinical responses or adverse events. Monitoring treatment-related effects on T cell subsets may therefore be part of (pre-)clinical studies for medicinal products. However, the extent of immune monitoring performed in studies for marketing authorisation and the degree of correspondence with data available in the public domain is not known. We evaluated the presence of T cell immunomonitoring in 46 registration dossiers of monoclonal antibodies indicated for immune-related disorders and published scientific papers. We found that the depth of Treg analysis in registration dossiers was rather small. Nevertheless, data on treatment-related Treg effects are available in public academia-driven studies (post-registration) and suggest that Tregs may act as a biomarker for clinical responses. However, public data are fragmented and obtained with heterogeneity of experimental approaches from a diversity of species and tissues. To reveal the potential added value of T cell (and particular Treg) evaluation in (pre-)clinical studies, more cell-specific data should be acquired, at least for medicinal products with an immunomodulatory mechanism. Therefore, extensive analysis of T cell subset contribution to clinical responses and the relevance of treatment-induced changes in their levels is needed. Preferably, industry and academia should work together to obtain these data in a standardised manner and to enrich our knowledge about T cell activity in disease pathogenesis and therapies. This will ultimately elucidate the necessity of T cell subset monitoring in the therapeutic benefit-risk assessment.

Deciphering and Reversing Immunosuppressive Cells in the Treatment of Hepatocellular Carcinoma

Use of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) has been partially successful. However, most HCC patients do not respond to immunotherapy. HCC has been shown to induce several immune suppressor mechanisms in patients. These suppressor mechanisms include involvement of myeloid-derived suppressor cells, regulatory T-cells, functionally impaired dendritic cells (DCs), neutrophils, monocytes, and tumor associated macrophages. The accumulation of immunosuppressive cells may lead to an immunosuppressive tumor microenvironment as well as the dense fibrotic stroma which may contribute to immune tolerance. Our laboratory has been investigating different cellular mechanisms of immune suppression in HCC patients. In vitro as well as in vivo studies have demonstrated that abrogation of the suppressor cells enhances or unmasks tumor-specific antitumor immune responses. Two or three effective systemic therapies including ICIs and/or molecular targeted therapies and the addition of innovative combination therapies targeting immune suppressor cells may lead to increased immune recognition with a greater tumor response. We reviewed the literature for the latest research on immune suppressor cells in HCC, and here we provide a comprehensive summary of the recent studies in this field.

Incidence of Endocrine Dysfunction Following the Use of Different Immune Checkpoint Inhibitor Regimens: A Systematic Review and Meta-analysis

Importance

If not promptly recognized, endocrine dysfunction can be life threatening. The incidence and risk of developing such adverse events (AEs) following the use of immune checkpoint inhibitor (ICI) regimens are unknown.

Objective

To compare the incidence and risk of endocrine AEs following treatment with US Food and Drug Administration-approved ICI regimens.

Data Sources

A PubMed search through July 18, 2016, using the following keywords was performed: "ipilimumab," "MDX-010," "nivolumab," "BMS-963558," "pembrolizumab," "MK-3475," "atezolizumab," "MPDL3280A," and "phase."

Study Selection

Thirty-eight randomized clinical trials evaluating the usage of these ICIs for treatment of advanced solid tumors were identified, resulting in a total of 7551 patients who were eligible for a meta-analysis. Regimens were categorized by class into monotherapy with a PD-1 (programmed cell death protein 1) inhibitor, a CTLA-4 (cytotoxic T-lymphocyte-associated protein-4) inhibitor, or a PD-L1 (programmed cell death 1 ligand 1) inhibitor, and combination therapy with PD-1 plus CTLA-4 inhibitors.

Data Extraction and Synthesis

The data were extracted by 1 primary reviewer (R.B.-S.) and then independently reviewed by 2 secondary reviewers (W.T.B. and A.C.G.-C.) following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Inferences on the incidence of AEs were made using log-odds random effects models.

Main Outcomes and Measures

Incidence of all-grade hypothyroidism, hyperthyroidism, hypophysitis, primary adrenal insufficiency, and insulin-deficient diabetes.

Results

Overall, 38 randomized clinical trials comprising 7551 patients were included in this systematic review and meta-analysis. The incidence of both hypothyroidism and hyperthyroidism was highest in patients receiving combination therapy. Patients on the combination regimen were significantly more likely to experience hypothyroidism (odds ratio [OR], 3.81; 95% CI, 2.10-6.91, P < .001) and hyperthyroidism (OR, 4.27; 95% CI, 2.05-8.90; P = .001) than patients on ipilimumab. Compared with patients on ipilimumab, those on PD-1 inhibitors had a higher risk of developing hypothyroidism (OR, 1.89; 95% CI, 1.17-3.05; P = .03). The risk of hyperthyroidism, but not hypothyroidism, was significantly greater with PD-1 than with PD-L1 inhibitors (OR, 5.36; 95% CI, 2.04-14.08; P = .002). While patients who received PD-1 inhibitors were significantly less likely to experience hypophysitis than those receiving ipilimumab (OR, 0.29; 95% CI, 0.18-0.49; P < .001), those who received combination therapy were significantly more likely to develop it (OR, 2.2; 95% CI, 1.39-3.60; P = .001). For primary adrenal insufficiency and insulin-deficient diabetes no statistical inferences were made due to the smaller number of events.

Conclusions and Relevance

Our study provides more precise data on the incidence of endocrine dysfunctions among patients receiving ICI regimens. Patients on combination therapy are at increased risk of thyroid dysfunction and hypophysitis.

Targeting the Immune Microenvironment in Lymphomas of B-Cell Origin: From Biology to Clinical Application

In lymphomas of B-cell origin, cancer cells orchestrate an inflammatory microenvironment of immune and stromal cells that sustain the tumor cell survival and growth, known as a tumor microenvironment (TME). The features of the TME differ between the different lymphoma types, ranging from extremely inflammatory, such as in Hodgkin lymphoma, to anergic, leading to immune deficiency and susceptibility to infections, such as in chronic lymphocytic leukemia. Understanding the characteristic features of the TME as well as the interactions between cancer and TME cells has given insight into the pathogenesis of most lymphomas and contributed to identify novel therapeutic targets. Here, we summarize the preclinical data that contributed to clarifying the role of the immune cells in the TME of different types of lymphomas of B-cell origin, and explain how the understanding of the biological background has led to new clinical applications. Moreover, we provide an overview of the clinical results of trials that assessed the safety and efficacy of drugs directly targeting TME immune cells in lymphoma patients.

Development of immune checkpoint therapy for cancer

Fritz and Lenardo discuss the basic science and clinical discoveries of immune checkpoint blockade, which boosts antitumor immunity and increases survival of patients with cancer.

Since the early 20th century, immunologists have investigated mechanisms that protect vertebrates from damaging immune responses against self-antigens by mature lymphocytes, i.e., peripheral tolerance. These mechanisms have been increasingly delineated at the molecular level, ultimately culminating in new therapeutics that have revolutionized clinical oncology. Here, we describe basic science and clinical discoveries that converge mainly on two molecules, CTLA-4 and PD-1, that were recognized with the 2018 Nobel Prize in Physiology or Medicine awarded to James Allison and Tasuku Honjo. We discuss their investigations and those of many others in the field that contravene tolerance through checkpoint inhibition to boost immune killing of malignant cells. We also discuss the mechanisms underlying each therapy, the efficacy achieved, and the complications of therapy. Finally, we hint at research questions for the future that could widen the success of cancer immunotherapy.

Update on systemic therapy for colorectal cancer: biologics take sides

Over the last decade, progress in the management of metastatic colorectal cancer (CRC) has focused on the development of biologic therapy in addition to the back bone of combination chemotherapy. Anti-epidermal growth factor receptor (EGFR) antibodies and agents targeting angiogenesis are widely used in the clinic, and more recently, in a subset of patients with mismatch repair (MMR) deficient cancer, immunotherapy with immune check point inhibitors have been integrated into clinical practice. The major challenge with the use of these biologic therapies is determining predictive biomarkers to optimize patient selection. In this review, we discuss the most recent updates in the use of biologic therapy in CRC. We review data on the role of primary tumor location (PTL) (sidedness) as predictive biomarker and recent advances in treatment of CRC with BRAF mutation.

Epidemiology, outcome, targeted agents and immunotherapy in adolescent and young adult non-Hodgkin and Hodgkin lymphoma

The epidemiology, outcome and targeted immunotherapy in adolescent and young adult non-Hodgkin and Hodgkin lymphoma were discussed during the 6th International Symposium on Childhood, Adolescent and Young Adult Non-Hodgkin Lymphoma September 26th-29th 2018 in Rotterdam, the Netherlands. This review summarizes some of those presentations, as well as other current and novel antibody therapy, immune check-point inhibitors, chimeric antigen receptor T cells, cancer vaccines and cytotoxic T lymphocyte therapy.

Early-drug development in the era of immuno-oncology: are we ready to face the challenges?

The classical development of drugs has progressively faded away, and we are currently in an era of seamless drug-development, where first-in-human trials include unusually big expansion cohorts in the search for early signs of activity and rapid regulatory approval. The fierce competition between different pharmaceutical companies and the hype for immune combinations obliges us to question the current way in which we are evaluating these drugs. In this review, we discuss critical issues and caveats in immunotherapy development. A particular emphasis is put on the limitations of pre-clinical toxicology studies, where both murine models and cynomolgus monkeys have underpredicted toxicity in humans. Moreover, relevant issues surrounding dose determination during phase I trials, such as dose-escalation methods or flat versus body-weight dosing, are discussed. A proposal of how to face these different challenges is offered, in order to achieve maximum efficacy with minimum toxicity for our patients.

Biomarkers for checkpoint inhibition in hematologic malignancies

In the past few years we have seen remarkable paradigm shifts in the treatment of many solid tumors due to the introduction of inhibitors targeting immune checkpoints such as PD-1/PD-L1 and CTLA-4. Recent results indicate that checkpoint inhibition also represents a very promising approach for certain types of hematologic malignancies. Unfortunately, treatment with checkpoint inhibitors is also associated with substantial toxicities and high costs and only a subset of patients appears to derive clinical benefit from these treatments. This demonstrates the urgent need for biomarkers for the identification of patient populations that are likely to respond to this type of therapy and/or have fewer side effects. Here, we have reviewed available information on the prognostic and predictive value of biomarkers for anti-CTLA-4 and anti-PD-1/PD-L1 as the most commonly used checkpoint inhibitors. There are currently no reliable biomarkers capable of predicting responses to anti-CTLA-4 agents, such as ipilimumab, in hematologic malignancies. Certain polymorphisms in the CTLA-4 gene, however, seem to have an impact on the patients' outcome, especially in the case of chronic lymphocytic leukemia (CLL). There is now sufficient data supporting PD-L1 expression levels in the tumor tissue as an independent prognostic factor in B cell lymphomas such as diffuse large B-cell lymphoma (DLBCL). Overexpression of PD-L1 in the tumor tissue and elevated serum levels of soluble PD-L1 may also represent adverse prognostic factors in certain subtypes of T cell lymphomas. Finally, expression levels of PD-L1 also seem to predict responses to anti-PD-1/PD-L1 approaches in patients with Hodgkin lymphoma. Future studies will have to further delineate the prognostic/predictive role of PD-L1 expression as a biomarker in hematologic malignancies and may be able to identify confounding variables, which will hopefully to some extent be generalizable to other types of anti-tumor immunotherapies.

Combination of immunotherapy with chemotherapy and radiotherapy in lung cancer: is this the beginning of the end for cancer?

Immune checkpoint inhibitors have significantly improved overall survival with an acceptable safety profile in a substantial proportion of non-small cell lung cancer (NSCLC) patients. However, not all patients are sensitive to immune checkpoint blockade and, in some cases, programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) inhibitors accelerate tumor progression. Several combination strategies are under evaluation, including the concomitant or sequential evaluation of chemotherapy or radiotherapy with immunotherapy. The current review provides an overview on the molecular rationale for the investigation of combinatorial approaches with chemotherapy or radiotherapy. Moreover, the results of completed clinical studies will be reported.

Immune Monitoring of Cancer Patients Prior to and During CTLA-4 or PD-1/PD-L1 Inhibitor Treatment

Targeting the immune checkpoint receptors cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death 1 ligand 1 (PD-L1) represents a very attractive treatment modality for tumor patients. The administration of antibodies against these receptors can promote efficient antitumor effects and can induce objective clinical responses in about 20–40% patients with various tumor types, accompanied by improved survival. Based on their therapeutic efficiency, several antibodies have been approved for the treatment of tumor patients. However, many patients do not respond to checkpoint inhibitor therapy. Therefore, the identification of biomarkers is required to guide patient selection for this treatment modality. Here, we summarize recent studies investigating the PD-L1 expression or mutational load of tumor tissues as well as the frequency and phenotype of immune cells in tumor patients prior to and during CTLA-4 or PD-1/PD-L1 inhibitor treatment.

Phenotypic and Functional Properties of Tumor-Infiltrating Regulatory T Cells

Regulatory T (Treg) cells maintain immune homeostasis by suppressing excessive immune responses. Treg cells induce tolerance against self- and foreign antigens, thus preventing autoimmunity, allergy, graft rejection, and fetus rejection during pregnancy. However, Treg cells also infiltrate into tumors and inhibit antitumor immune responses, thus inhibiting anticancer therapy. Depleting whole Treg cell populations in the body to enhance anticancer treatments will produce deleterious autoimmune diseases. Therefore, understanding the precise nature of tumor-infiltrating Treg cells is essential for effectively targeting Treg cells in tumors. This review summarizes recent results relating to Treg cells in the tumor microenvironment, with particular emphasis on their accumulation, phenotypic, and functional properties, and targeting to enhance the efficacy of anticancer treatment.

Phase I Dose-Escalation Study of Anti-CTLA-4 Antibody Ipilimumab and Lenalidomide in Patients with Advanced Cancers

Preclinical data suggest that combining a checkpoint inhibition with immunomodulatory derivative can increase anticancer response. We designed a dose-escalation study using a 3 + 3 design to determine the safety, maximum tolerated dose (MTD) or recommended phase II dose (R2PD) and dose-limiting toxicities (DLT) of the anti-CTLA-4 antibody ipilimumab (1.5-3 mg/kg intravenously every 28 days × 4) and lenalidomide (10-25 mg orally daily for 21 of 28 days until disease progression or unacceptable toxicity) in advanced cancers. Total of 36 patients (Hodgkin lymphoma, 7; melanoma, 5; leiomyosarcoma, 4; renal cancer, 3; thyroid cancer, 3; other cancers, 14; median of 3 prior therapies) were enrolled. The MTD has not been reached and ipilimumab 3 mg/kg and lenalidomide 25 mg have been declared as R2PD. DLT were grade (G) 3 rash (3 patients) and G3 pancreatitis (1 patient). G3/4 drug-related toxicities other than DLT were G3 anemia (5 patients), G3 thromboembolism (2 patients), G3 thrombocytopenia, G3 rash, G3 hypopituitarism, G3 pneumonitis, G3 transaminitis, and G4 hypopituitarism (all in 1 patient). Eight patients had tumor shrinkage per immune-related response criteria (-79% to -2%) including a PR (-79% for 7.2+ months) in a refractory Hodgkin lymphoma. Using comprehensive genomic profiling, a total mutation burden (mutations/Mb) was evaluated in 17 patients, with one of the patients achieving a PR demonstrated intermediate mutation burden. In conclusion, combination of ipilimumab and lenalidomide is well tolerated and demonstrated preliminary signals of activity in patients with refractory Hodgkin lymphoma and other advanced cancers. Mol Cancer Ther; 17(3); 671-6. ©2017 AACR.

Developing T-cell therapies for lymphoma without receptor engineering

T-cell therapy has emerged from the bench for the treatment of patients with lymphoma. Responses to T-cell therapeutics are regulated by multiple factors, including the patient's immune system status and disease stage. Outside of engineering of chimeric antigen receptors and artificial T-cell receptors, T-cell therapy can be mediated by ex vivo expansion of antigen-specific T cells targeting viral and/or nonviral tumor-associated antigens. These approaches are contributing to enhanced clinical responses and overall survival. In this review, we summarize the available T-cell therapeutics beyond receptor engineering for the treatment of patients with lymphoma.

Developing T-cell therapies for lymphoma without receptor engineering

T-cell therapy has emerged from the bench for the treatment of patients with lymphoma. Responses to T-cell therapeutics are regulated by multiple factors, including the patient's immune system status and disease stage. Outside of engineering of chimeric antigen receptors and artificial T-cell receptors, T-cell therapy can be mediated by ex vivo expansion of antigen-specific T cells targeting viral and/or nonviral tumor-associated antigens. These approaches are contributing to enhanced clinical responses and overall survival. In this review, we summarize the available T-cell therapeutics beyond receptor engineering for the treatment of patients with lymphoma.

Immunotherapy for Gastric Cancer: A Focus on Immune Checkpoints

Gastric cancer (GC) is a major world-wide health problem. It is the third leading cause of death from cancer. The treatment of advanced GC by chemotherapy has limited efficacy. The addition of some targeted therapies like trastuzumab and ramucirumab have added a modest benefit, but only in human epidermal growth factor receptor 2 (ERBB2 or HER2)-positive patients and in the second-line setting, respectively. The development of new and effective therapeutic strategies must consider the genetic complexity and heterogeneity of GC; prognostic and predictive biomarkers should be identified for clinical implementation. Immune deregulation has been associated with some GC subtypes, especially those that are associated with virus infection and those with a high mutational rate. Different mechanisms to prevent immunologic escape have been characterized during the last years; in particular the PD-1/PD-L1 inhibitors pembrolizumab, avelumab, durvalumab and atezolizumab have shown early sign of efficacy. Therefore, immunotherapeutic strategies may provide new opportunities for GC patients. This review will discuss (1) the main characteristics of GC treatment, (2) the immune response in GC, and (3) the current status of immune-related strategies in clinical development in GC patients, focusing on immune checkpoints therapies.

Phase III Trial of Ipilimumab Combined With Paclitaxel and Carboplatin in Advanced Squamous Non-Small-Cell Lung Cancer

Purpose Patients with squamous non-small-cell lung cancer (NSCLC) have poor prognosis and limited treatment options. This randomized, double-blind, phase III study investigated the efficacy and safety of first-line ipilimumab or placebo plus paclitaxel and carboplatin in advanced squamous NSCLC. Patients and Methods Patients with stage IV or recurrent chemotherapy-naïve squamous NSCLC were randomly assigned (1:1) to receive paclitaxel and carboplatin plus blinded ipilimumab 10 mg/kg or placebo every 3 weeks on a phased induction schedule comprising six chemotherapy cycles, with ipilimumab or placebo from cycles 3 to 6 and then, after induction treatment, ipilimumab or placebo maintenance every 12 weeks for patients with stable disease or better. The primary end point was overall survival (OS) in patients receiving at least one dose of blinded study therapy. Results Of 956 randomly assigned patients, 749 received at least one dose of blinded study therapy (chemotherapy plus ipilimumab, n = 388; chemotherapy plus placebo, n = 361). Median OS was 13.4 months for chemotherapy plus ipilimumab and 12.4 months for chemotherapy plus placebo (hazard ratio, 0.91; 95% CI, 0.77 to 1.07; P = .25). Median progression-free survival was 5.6 months for both groups (hazard ratio, 0.87; 95% CI, 0.75 to 1.01). Rates of grade 3 or 4 treatment-related adverse events (TRAEs), any-grade serious TRAEs, and TRAEs leading to discontinuation were numerically higher with chemotherapy plus ipilimumab (51%, 33%, and 28%, respectively) than with chemotherapy plus placebo (35%, 10%, and 7%, respectively). Seven treatment-related deaths occurred with chemotherapy plus ipilimumab, and one occurred with chemotherapy plus placebo. Conclusion The addition of ipilimumab to first-line chemotherapy did not prolong OS compared with chemotherapy alone in patients with advanced squamous NSCLC. The safety profile of chemotherapy plus ipilimumab was consistent with that observed in previous lung and melanoma studies. Ongoing studies are evaluating ipilimumab in combination with nivolumab in this population.

免疫检查点抑制剂在结直肠癌中的应用以及未来发展方向

结直肠癌(colorectal cancer, CRC)是消化系最常见的恶性肿瘤之一, 在我国, 其发病率及死亡率处于逐年上升趋势, 且总体预后相对较差. 近年来, 免疫治疗的基础和临床研究都获得了快速发展, 已成为肿瘤研究的热点. 其中, 免疫检查点抑制剂已经被批准用于包括CRC在内的多种实体肿瘤的临床治疗. 本文将重点阐述免疫检查点的作用、机制和免疫检查点抑制剂在CRC中应用的最新进展, 以及影响其抗肿瘤疗效的因素. 已经完成和正在进行的临床试验肯定了免疫检查点抑制剂在CRC的治疗中的潜力, 尽管部分患者仍对免疫检查点治疗无应答. 因此, 探究免疫检查点抑制剂治疗CRC患者的敏感因素, 对实现个体化精准治疗至关重要. 未来, 免疫检查点抑制剂有望和其他多种治疗方法相联合, 提高患者反应率, 延长患者的生存期.

The proportion of circulating CD45RO+CD8+ memory T cells is correlated with clinical response in melanoma patients treated with ipilimumab

BACKGROUND

Immune checkpoint blockade (ICB) has been a breakthrough in the treatment of metastatic melanoma. But with only about 20-40% long-term responders and severe side-effects in about 12-17%, finding predictive markers for treatment response is of great interest.

METHODS

We prospectively assessed clinical data, haematologic parameters and freshly isolated peripheral blood mononuclear cells of 30 patients treated with ipilimumab (n = 21) and pembrolizumab (n = 9) prior to the first 4 cycles with ICB and before the first tumour assessment.

RESULTS

We discovered that the baseline levels of CD45RO⁺CD8⁺ T cells significantly differed among the patients. Thirteen (43%) of our patients had normal baseline levels of CD45RO⁺CD8⁺ T cells, whereas 17 (57%) patients were low on CD45RO⁺CD8⁺ T cells. The baseline levels of CD45RO⁺CD8⁺ T cells correlated significantly with the response to ipilimumab but not pembrolizumab. Patients with baseline levels of lower/equal 25% of CD45RO⁺CD8⁺ T cells did not respond to treatment with ipilimumab. Phenotyping the CD8⁺ T cells in patients treated with ipilimumab revealed an activated HLA-DR⁺CD25^- phenotype, implying antigen non-specific stimulation. The levels of the HLA-DR⁺CD25^-CD8⁺ T cells were significantly higher in patients with a normal baseline of CD45RO⁺CD8⁺ T cells and even increased significantly during treatment. Furthermore, proliferation of melanoma antigen recognized by T cells 1 (MART-1)-specific CD8⁺ T cells was not observed. Patients with normal baseline levels of CD45RO⁺CD8⁺ T cells showed a significant longer overall survival when treated with ipilimumab but not pembrolizumab.

CONCLUSION

Patients with normal baseline levels of CD45RO⁺CD8⁺ T cells respond significantly more frequently to treatment with ipilimumab and the CD8⁺ T cells appear to be antigen non-specifically activated. The baseline level of CD45RO⁺CD8⁺ T cells represents a promising factor as biomarker for the prediction of the response to ipilimumab.

Clinical Outcomes of Specific Immunotherapy in Advanced Pancreatic Cancer: A Systematic Review and Meta-Analysis

Specific immunotherapies, including vaccines with autologous tumor cells and tumor antigen-specific monoclonal antibodies, are important treatments for PC patients. To evaluate the clinical outcomes of PC-specific immunotherapy, we performed a systematic review and meta-analysis of the relevant published clinical trials. The effects of specific immunotherapy were compared with those of nonspecific immunotherapy and the meta-analysis was executed with results regarding the overall survival (OS), immune responses data, and serum cancer markers data. The pooled analysis was performed by using the random-effects model. We found that significantly improved OS was noted for PC patients utilizing specific immunotherapy and an improved immune response was also observed. In conclusion, specific immunotherapy was superior in prolonging the survival time and enhancing immunological responses in PC patients.

Immune Checkpoint Therapies in Prostate Cancer

Advanced prostate cancer is the second leading cause of death from cancer in the United States. In the era of cancer immunotherapy, it was the first malignancy to demonstrate improved survival with a cancer-specific vaccine, thus proving that prostate cancer is an immune-responsive disease. However, the success with immune checkpoint therapies in metastatic prostate cancer has been limited to date with only a subset of patients experiencing clinical benefit. The relative lack of response could be attributed to patient selection based on clinical attributes and the tumor microenvironment. Here, we review the current data on immune checkpoint therapies in prostate cancer and propose future directions.

Is There Still Room for Cancer Vaccines at the Era of Checkpoint Inhibitors

Checkpoint inhibitor (CPI) blockade is considered to be a revolution in cancer therapy, although most patients (70%–80%) remain resistant to this therapy. It has been hypothesized that only tumors with high mutation rates generate a natural antitumor T cell response, which could be revigorated by this therapy. In patients with no pre-existing antitumor T cells, a vaccine-induced T cell response is a rational option to counteract clinical resistance. This hypothesis has been validated in preclinical models using various cancer vaccines combined with inhibitory pathway blockade (PD-1-PDL1-2, CTLA-4-CD80-CD86). Enhanced T cell infiltration of various tumors has been demonstrated following this combination therapy. The timing of this combination appears to be critical to the success of this therapy and multiple combinations of immunomodulating antibodies (CPI antagonists or costimulatory pathway agonists) have reinforced the synergy with cancer vaccines. Only limited results are available in humans and this combined approach has yet to be validated. Comprehensive monitoring of the regulation of CPI and costimulatory molecules after administration of immunomodulatory antibodies (anti-PD1/PD-L1, anti-CTLA-4, anti-OX40, etc.) and cancer vaccines should help to guide the selection of the best combination and timing of this therapy.

Immune phenotypes of prostate cancer cells: Evidence of epithelial immune cell-like transition?

Prostate cancers (PCa) have been reported to actively suppress antitumor immune responses by creating an immune-suppressive microenvironment. There is mounting evidence that PCas may undergo an ''Epithelial Immune Cell-like Transition'' (EIT) by expressing molecules conventionally associated with immune cells (e.g., a variety of cytokines/receptors, immune transcription factors, Ig motifs, and immune checkpoint molecules), which subsequently results in the suppression of anti-cancer immune activity within the tumor microenvironment. Recent progress within the field of immune therapy has underscored the importance of immune checkpoint molecules in cancer development, thus leading to the development of novel immunotherapeutic approaches. Here, we review the expression of select immune checkpoint molecules in PCa epithelial and associated immune cells, with particular emphasis on clinical data supporting the concept of an EIT-mediated phenotype in PCa. Furthermore, we summarize current advances in anti-immune checkpoint therapies, and provide perspectives on their potential applicability.

Regulatory T Cells in the Tumor Microenvironment and Cancer Progression: Role and Therapeutic Targeting

Recent years have seen significant efforts in understanding and modulating the immune response in cancer. In this context, immunosuppressive cells, including regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs), have come under intense investigation for their proposed roles in suppressing tumor-specific immune responses and establishing an immunosuppressive tumor microenvironment, thus enabling tumor immune evasion. Additionally, recent evidence indicates that Tregs comprise diverse and heterogeneous subsets; phenotypically and functionally distinct subsets of tumor-infiltrating Tregs could contribute differently to cancer prognosis and clinical outcomes. Understanding Treg biology in the setting of cancer, and specifically the tumor microenvironment, is important for designing effective cancer therapies. In this review, we critically examine the role of Tregs in the tumor microenvironment and in cancer progression focusing on human studies. We also discuss the impact of current therapeutic modalities on Treg biology and the therapeutic opportunities for targeting Tregs to enhance anti-tumor immune responses and clinical benefits.

Current Status and Perspective of Immunotherapy in Gastrointestinal Cancers

Cancer immunotherapy is at dawn of the Renaissance after the Medieval Dark Ages. Recent advances of understanding tumor immunology and molecular drug development are leading us to the epoch of cancer immunotherapy. Some types of immunotherapy have shown to provide survival benefit for patients with solid tumors such as malignant melanoma, renal cell carcinoma, or non-small cell lung cancer. Several studies have suggested that immune checkpoint inhibition might be effective in some patients with gastrointestinal cancers. However, the era of cancer immunotherapy in gastrointestinal cancers is still in an inchoate stage. Here we briefly review the current status and perspective of immunotherapeutic approaches in patients with gastrointestinal cancers.

Improving therapeutic activity of anti-CD20 antibody therapy through immunomodulation in lymphoid malignancies

Nearly two decades ago rituximab heralded a new era in management of B cell malignancies significantly increasing response rates and survival. However, despite clear therapeutic advantage, significant numbers of patients become refractory to anti-CD20 mAb therapy, suggesting urgent improvements are required. It is now well recognized that the suppressive tumor microenvironment plays an important role in the outcome of anti-CD20 mAb therapy and that manipulation of this environment may improve the efficacy and produce long-term tumor control. The past few years have seen a surge of interest in immunomodulatory agents capable of overwriting immune suppressive networks into favorable clinical outcome. Currently, a number of such combinations with anti-CD20 mAb is under evaluation and some have produced encouraging outcomes in rituximab refractory disease. In this review, we give an outline of anti-CD20 mAbs and explore the combinations with immunomodulatory agents that enhance antitumor immunity through targeting stimulatory or inhibitory pathways and have proven potential to synergize with anti-CD20 mAb therapy. These agents, primarily mAbs, target CTLA-4, PD-1/PD-L1, and CD40.

Immunological correlates of treatment and response in stage IV malignant melanoma patients treated with Ipilimumab

Introduction: Ipilimumab is effective in the treatment of metastatic malignant melanoma, but few biomarkers reliably predict treatment response. Methods: Patients were treated with Ipilimumab for metastatic malignant melanoma. Blood and serum samples were collected before and during treatment. Mononuclear cells in peripheral blood were subjected to immune phenotypic analyses and cytokine levels were measured in serum samples. Results were correlated with clinical data. Results: A total of 40 patients were included in the analyses. Clinical response were associated with an increase after one series of treatment in absolute lymphocyte count (ALC) (p = 0.008), absolute T cell count (p = 0.02) and the absolute number of activated T cells in peripheral blood (p = 0.003). A high frequency of myeloid derived suppressor cells (MDSC) and a higher level of IL6 were associated with treatment failure, though not significantly. Levels of IL6 in serum above the median showed a tendency to associate with reduced survival by the 4th treatment series. Finally, treatment with Ipilimumab led to a decreased frequency of FOXP3+ regulatory T cells (p = 0.009). Conclusion: Ipilimumab leads to increased ALC, T cell count and T cell activation in malignant melanoma patients responding to treatment. A high baseline frequency of myeloid-derived suppressor cells and high levels of IL6 is associated with a reduced chance of responding to therapy.

Lymphoma Microenvironment and Immunotherapy

Understanding of the lymphoma tumor microenvironment is poised to expand in the era of next-generation sequencing studies of the tumor cells themselves. Successful therapies of the future will rely on deeper appreciation of the interactions between elements of the microenvironment. Although the phenotypic, cytogenetic, and molecular characterization of tumor cells in lymphomas has progressed faster than most other solid organ tumors, concrete advancements in understanding the lymphoma microenvironment have been fewer. This article explores the composition of the lymphoma tumor microenvironment; its role in immune surveillance, evasion, and drug resistance; and its potential role in the development of targeted therapies.

Novel technologies and emerging biomarkers for personalized cancer immunotherapy

The culmination of over a century's work to understand the role of the immune system in tumor control has led to the recent advances in cancer immunotherapies that have resulted in durable clinical responses in patients with a variety of malignancies. Cancer immunotherapies are rapidly changing traditional treatment paradigms and expanding the therapeutic landscape for cancer patients. However, despite the current success of these therapies, not all patients respond to immunotherapy and even those that do often experience toxicities. Thus, there is a growing need to identify predictive and prognostic biomarkers that enhance our understanding of the mechanisms underlying the complex interactions between the immune system and cancer. Therefore, the Society for Immunotherapy of Cancer (SITC) reconvened an Immune Biomarkers Task Force to review state of the art technologies, identify current hurdlers, and make recommendations for the field. As a product of this task force, Working Group 2 (WG2), consisting of international experts from academia and industry, assembled to identify and discuss promising technologies for biomarker discovery and validation. Thus, this WG2 consensus paper will focus on the current status of emerging biomarkers for immune checkpoint blockade therapy and discuss novel technologies as well as high dimensional data analysis platforms that will be pivotal for future biomarker research. In addition, this paper will include a brief overview of the current challenges with recommendations for future biomarker discovery.

Novel technologies and emerging biomarkers for personalized cancer immunotherapy

The culmination of over a century’s work to understand the role of the immune system in tumor control has led to the recent advances in cancer immunotherapies that have resulted in durable clinical responses in patients with a variety of malignancies. Cancer immunotherapies are rapidly changing traditional treatment paradigms and expanding the therapeutic landscape for cancer patients. However, despite the current success of these therapies, not all patients respond to immunotherapy and even those that do often experience toxicities. Thus, there is a growing need to identify predictive and prognostic biomarkers that enhance our understanding of the mechanisms underlying the complex interactions between the immune system and cancer. Therefore, the Society for Immunotherapy of Cancer (SITC) reconvened an Immune Biomarkers Task Force to review state of the art technologies, identify current hurdlers, and make recommendations for the field. As a product of this task force, Working Group 2 (WG2), consisting of international experts from academia and industry, assembled to identify and discuss promising technologies for biomarker discovery and validation. Thus, this WG2 consensus paper will focus on the current status of emerging biomarkers for immune checkpoint blockade therapy and discuss novel technologies as well as high dimensional data analysis platforms that will be pivotal for future biomarker research. In addition, this paper will include a brief overview of the current challenges with recommendations for future biomarker discovery.

Innovative perspectives of immunotherapy in head and neck cancer. From relevant scientific rationale to effective clinical practice

It is now well established that head and neck cancer carcinogenesis is characterized by genetic instability and several immune defects, leading to unique host-tumor interactions. In such condition, recent improved comprehension and relevant findings could lead to identification of innovative molecular therapeutic targets, achieving considerable clinical and translational research. This review aims to summarize and to highlight most recent and relevant scientific rationale in this era of immunotherapy revival, and to correlate it to the near future clinical practice for the management of this challenging disease.

Vaccination strategies in lymphoproliferative disorders: Failures and successes

Anti-tumor vaccines in lymphoproliferative disorders hold out the prospect of effective tumor therapies with minimal side effects. The addition of immunotherapy to old and new chemotherapy regimens has improved both response rates and disease-free survival, leading in many cases to an extended overall survival. Ideally, an antigen that is used for vaccination would be specifically expressed in the tumor; it must have an important, causal part in the multifactorial process that leads to cancer, and it must be expressed stably even after it is attacked by the immune system. Immunotherapies, which aim to activate the immune system to kill cancer cells, include strategies to increase the frequency or potency of antitumor T cells, to overcome suppressive factors in the tumor microenvironment, and to reduce T-cell suppression systemically. In this review, we focus on the results of clinical trials of vaccination in lymphoma, and discuss potential strategies to enhance the efficacy of immunotherapy in the future.

The Macrophage Galactose-Type C-Type Lectin (MGL) Modulates Regulatory T Cell Functions

Regulatory T cells (Tregs) are physiologically designed to prevent autoimmune disease and maintain self-tolerance. In tumour microenvironments, their presence is related to a poor prognosis, and they influence the therapeutic outcome due to their capacity to suppress the immune response by cell-cell contact and to release immunosuppressive cytokines. In this study, we demonstrate that Treg immunosuppressive activity can be modulated by the cross-linking between the CD45RA expressed by Tregs and the C-type lectin MGL. This specific interaction strongly decreases the immunosuppressive activity of Tregs, restoring the proliferative capacity of co-cultured T lymphocytes. This effect can be attributed to changes in CD45RA and TCR signalling through the inhibition of Lck and inactivation of Zap-70, an increase in the Foxp3 methylation status and, ultimately, the reduced production of suppressive cytokines. These results indicate a role of MGL as an immunomodulator within the tumour microenvironment interfering with Treg functions, suggesting its possible use in the design of anticancer vaccines.

T cell coinhibition in prostate cancer: new immune evasion pathways and emerging therapeutics

T cell-mediated adaptive immune response is controlled by both positive costimulation and negative coinhibition, generated mainly by the interaction between the B7 family and their receptor CD28 family. Coinhibition is exploited by prostate cancer as an immune evasion pathway. Overexpression of coinhibitory B7x and B7-H3 in prostate cancer correlates with poor disease outcome, whereas tumor-infiltrating immune cells have enhanced expression of PD-L1 and its receptor PD-1. New insights into the complex mechanisms governing B7 expression in the tumor microenvironment have been reported and therapies aimed at overcoming T cell coinhibition with antagonistic monoclonal antibodies are emerging as effective tumor immunotherapies. Therapies that block B7x and B7-H3, either as monotherapies or in synergism with traditional therapies, should be pursued.

Immunotherapy of Metastatic Colorectal Cancer: Prevailing Challenges and New Perspectives

Patients with recurring or metastatic colorectal cancer (mCRC) have strikingly low long-term survival, while conventional treatments such as chemotherapeutic intervention and radiation therapy marginally improve longevity. Although, many factors involving immunosurveillance and immunosuppression were recently validated as important for patient prognosis and care, a multitude of experimental immunotherapies designed to combat unresectable mCRC have, in few cases, successfully mobilized antitumor immune cells against malignancies, nor conclusively or consistently granted protection, complete remission, and/or stable disease from immunotherapy - of which benefit less than 10% of those receiving therapy. After decades of progress, however, new insights into the mechanisms of immunosuppression, tolerance, and mutation profiling established novel therapies that circumvent these immunological barriers. This review underlines the most exciting methods to date that manipulate immune cells to curb mCRC, including adoptive cell therapy, dendritic cell vaccines, and checkpoint inhibitor antibodies - of which hint at effective and enduring protection against disease progression and undetected micrometastases.

Lymphoma: immune evasion strategies

While the cellular origin of lymphoma is often characterized by chromosomal translocations and other genetic aberrations, its growth and development into a malignant neoplasm is highly dependent upon its ability to escape natural host defenses. Neoplastic cells interact with a variety of non-malignant cells in the tumor milieu to create an immunosuppressive microenvironment. The resulting functional impairment and dysregulation of tumor-associated immune cells not only allows for passive growth of the malignancy but may even provide active growth signals upon which the tumor subsequently becomes dependent. In the past decade, the success of immune checkpoint blockade and adoptive cell transfer for relapsed or refractory lymphomas has validated immunotherapy as a possible treatment cornerstone. Here, we review the mechanisms by which lymphomas have been found to evade and even reprogram the immune system, including alterations in surface molecules, recruitment of immunosuppressive subpopulations, and secretion of anti-inflammatory factors. A fundamental understanding of the immune evasion strategies utilized by lymphomas may lead to better prognostic markers and guide the development of targeted interventions that are both safer and more effective than current standards of care.