Current developments in cancer vaccines and cellular immunotherapy

Graphene oxide as novel vaccine adjuvant

To improve antigen immunogenicity and promote long-lasting immunity, vaccine formulations have been appropriately supplemented with adjuvants. Graphene has been found to enhance the presentation of antigens to CD8+ T cells, as well as stimulating innate immune responses and inflammatory factors. Its properties, such as large surface area, water stability, and high aspect ratio, make it a suitable candidate for delivering biological substances. Graphene-based nanomaterials have recently attracted significant attention as a new type of vaccine adjuvants due to their potential role in the activation of immune responses. Due to the limited functionality of some approved human adjuvants for use, the development of new all-purpose adjuvants is urgently required. Research on the immunological and biomedical use of graphene oxide (GO) indicates that these nanocarriers possess excellent physicochemical properties, acceptable biocompatibility, and a high capacity for drug loading. Graphene-based nanocarriers also could improve the function of some immune cells such as dendritic cells and macrophages through specific signaling pathways. However, GO injection can lead to significant oxidative stress and inflammation. Various surface functionalization protocols have been employed to reduce possible adverse effects of GO, such as aggregation of GO in biological liquids and induce cell death. Furthermore, these modifications enhance the properties of functionalized-GO's qualities, making it an excellent carrier and adjuvant. Shedding light on different physicochemical and structural properties of GO and its derivatives has led to their application in various therapeutic and drug delivery fields. In this review, we have endeavored to elaborate on different aspects of GO.

Immunotherapy in Biliary Tract Cancers: Where Are We?

PURPOSE OF REVIEW

Biliary tract cancers (BTCs) are a heterogenous group of cancers arising from the biliary tract. The hallmark of these cancers is the advanced stage of presentation and a paucity of durable treatment options. Despite the advances in targeted therapy and immunotherapy in solid tumors, systemic cytotoxic chemotherapy has remained the mainstay for cholangiocarcinomas.

RECENT FINDINGS

With advances in the understanding of the tumor microenvironment, genetic features, and inflammatory milieu, have led to the identification of tumor-infiltrating immune cells as indicators of prognosis and response to treatment in BTC. Through an improved comprehension of immunology, immuno-oncology is becoming another pillar of treatment along with traditional radiation, surgery, cytotoxic chemotherapy, and targeted therapies. This article reviews the evidence for immunotherapy use in cholangiocarcinoma, which still being in infancy, and offers promising new novel options for the management of biliary tract cancers.

Can EGFR be a therapeutic target in breast cancer?

Epidermal growth factor receptor (EGFR) is highly expressed in certain cancer types and is involved in regulating the biological characteristics of cancer progression, including proliferation, metastasis, and drug resistance. Various medicines targeting EGFR have been developed and approved for several cancer types, such as lung and colon cancer. To date, however, EGFR inhibitors have not achieved satisfactory clinical results in breast cancer, which continues to be the most serious malignant tumor type in females. Therefore, clarifying the underlying mechanisms related to the ineffectiveness of EGFR inhibitors in breast cancer and developing new EGFR-targeted strategies (e.g., combination therapy) remain critical challenges. Various studies have demonstrated aberrant expression and maintenance of EGFR levels in breast cancer. In this review, we summarize the regulatory mechanisms underlying EGFR protein expression in breast cancer cells, including EGFR mutations, amplification, endocytic dysfunction, recycling acceleration, and degradation disorders. We also discuss potential therapeutic strategies that act directly or indirectly on EGFR, including reducing EGFR protein expression, treating the target protein to mediate precise clearance, and inhibiting non-EGFR signaling pathways. This review should provide new therapeutic perspectives for breast cancer patients with high EGFR expression.

Combination of GNRs-PEI/cGAMP-laden macrophages-based photothermal induced in situ tumor vaccines and immune checkpoint blockade for synergistic anti-tumor immunotherapy

Immunotherapy is an effective strategy to control and eliminate primary and metastatic tumor by restarting and restoring the specific anti-tumor immune response. However, tumor immunotherapy often showed limited efficacy due to the poor T cell responses in vivo and the tumor suppressive microenvironments. Herein, we constructed polyethyleimine modified gold nanorods (GNRs-PEI) by conjugating PEI to GNRs via SAu bonds. GNRs-PEI/cGAMP nanoparticles were formed via electrostatic interaction and then loaded by macrophages. The GNRs-PEI/cGAMP-laden macrophages (GPc-RAWs) were intravenously injected into the tumor bearing mice and the in situ tumor vaccines were obtained after NIR irradiation. Besides, anti-PD-L1 antibody, an immune checkpoint inhibitor, was introduced to reverse immunosuppressive microenvironment and assisted to achieve the synergistic anti-tumor immunotherapy. GNRs-PEI/cGAMP-laden macrophages with NIR irradiation could effectively inhibit the primary tumors, while little effect for the contralateral tumors. When combined with anti-PD-L1 antibody, the combined strategy not only inhibited the growth of primary tumor, but also significantly delayed the proliferation of the contralateral tumors. More importantly, this strategy reversed immunosuppressive microenvironment without obvious side effects. Therefore, this study provided a great immunotherapy platform for the efficient treatment of primary and metastatic tumors.

Immunotherapy of Ovarian Cancer with Particular Emphasis on the PD-1/PDL-1 as Target Points

Simple Summary

Ovarian cancer has remained the leading cause of death among gynecologic malignancies. The current standard of treatment, in most cases, is a combination of surgery and chemotherapy, based on platinum agents and taxanes. Despite the increasing usage of newer drug groups, such as bevacizumab and PARP inhibitors, and the expansion of patient groups for these drugs, ovarian cancer is characterized by recurrences, particularly in the form of peritoneal implants. This review focuses on immunotherapy for ovarian cancer. It considers the current state of knowledge in areas such as cancer vaccines, adoptive cell therapy, CAR-T therapy, and anti-CTLA-4 monotherapy. The paper specifically considers PD-1/PDL-1 as drug targets. Anti-PD-1/PD-L1 monotherapy, and anti-PD-1/PD-L1 immunotherapy in combination with other agents, are analyzed.

Abstract

Ovarian cancer is one of the most fatal cancers in women worldwide. Cytoreductive surgery combined with platinum-based chemotherapy has been the current first-line treatment standard. Nevertheless, ovarian cancer appears to have a high recurrence rate and mortality. Immunological processes play a significant role in tumorigenesis. The production of ligands for checkpoint receptors can be a very effective, and undesirable, immunosuppressive mechanism for cancers. The CTLA-4 protein, as well as the PD-1 receptor and its PD-L1 ligand, are among the better-known components of the control points. The aim of this paper was to review current research on immunotherapy in the treatment of ovarian cancer. The authors specifically considered immune checkpoints molecules such as PD-1/PDL-1 as targets for immunotherapy. We found that immune checkpoint-inhibitor therapy does not have an improved prognosis in ovarian cancer; although early trials showed that a combination of anti-PD-1/PD-L1 therapy with targeted therapy might have the potential to improve responses and outcomes in selected patients. However, we must wait for the final results of the trials. It seems important to identify a group of patients who could benefit significantly from treatment with immune checkpoints inhibitors. However, despite numerous trials, ICIs have not become part of routine clinical practice for the treatment of ovarian cancer.

A topography of immunotherapies against gastrointestinal malignancies

Gastrointestinal (GI) cancers are one of the leading causes of death worldwide. Although various approaches are implemented to improve the health condition of GI patients, none of the treatment protocols promise for eradicating cancer. However, a treatment mechanism against any kind of disease condition is already existing executing inside the human body. The 'immune system' is highly efficient to detect and destroy the unfavourable events of the body including tumor cells. The immune system can restrict the growth and proliferation of cancer. Cancer cells behave much smarter and adopt new mechanisms for hiding from the immune cells. Thus, cancer immunotherapy might play a decisive role to train the immune system against cancer. In this review, we have discussed the immunotherapy permitted for the treatment of GI cancers. We have discussed various methods and mechanisms, periodic development of cancer immunotherapies, approved biologicals, completed and ongoing clinical trials, role of various biopharmaceuticals, and epigenetic factors involved in GI cancer immunotherapies (graphical abstract Figure 1).

Immune Checkpoint Inhibitor-Based Strategies for Synergistic Cancer Therapy

Immune checkpoint blockade therapy (ICBT) targeting checkpoints, such as, cytotoxic T-lymphocyte associated protein-4 (CTLA-4), programmed death-1 (PD-1), or programmed death-ligand 1 (PD-L1), can yield durable immune response in various types of cancers and has gained constantly increasing research interests in recent years. However, the efficacy of ICBT alone is limited by low response rate and immune-related side effects. Emerging preclinical and clinical studies reveal that chemotherapy, radiotherapy, phototherapy, or other immunotherapies can reprogramm immunologically "cold" tumor microenvironment into a "hot" one, thus synergizing with ICBT. In this review, the working principle and current development of various immune checkpoint inhibitors are summarized, while the interactive mechanism and recent progress of ICBT-based synergistic therapies with other immunotherapy, chemotherapy, phototherapy, and radiotherapy in fundamental and clinical studies in the past 5 years are depicted and highlighted. Moreover, the potential issues in current studies of ICBT-based synergistic therapies and future perspectives are also discussed.

Is immunotherapy in the future of therapeutic management of sarcomas?

Sarcomas are rare, ubiquitous and heterogeneous tumors usually treated with surgery, chemotherapy, target therapy, and radiotherapy. However, 25-50% of patients experience local relapses and/or distant metastases after chemotherapy with an overall survival about 12-18 months. Recently, immuno-therapy has revolutionized the cancer treatments with initial indications for non-small cell lung cancer (NSCLC) and melanoma (immune-checkpoint inhibitors).Here, we provide a narrative review on the topic as well as a critical description of the currently available trials on immunotherapy treatments in patients with sarcoma. Given the promising results obtained with anti-PD-1 monoclonal antibodies (pembrolizumab and nivolumab) and CAR-T cells, we strongly believe that these new immunotherapeutic approaches, along with an innovative characterization of tumor genetics, will provide an exciting opportunity to ameliorate the therapeutic management of sarcomas.

How to Best Exploit Immunotherapeutics in Advanced Gastric Cancer: Between Biomarkers and Novel Cell-Based Approaches

Despite extensive research efforts, advanced gastric cancer still has a dismal prognosis with conventional treatment options. Immune checkpoint inhibitors have revolutionized the treatment landscape for many solid tumors. Amongst gastric cancer subtypes, tumors with microsatellite instability and Epstein Barr Virus positive tumors provide the strongest rationale for responding to immunotherapy. Various predictive biomarkers such as mismatch repair status, programmed death ligand 1 expression, tumor mutational burden, assessment of tumor infiltrating lymphocytes and circulating biomarkers have been evaluated. However, results have been inconsistent due to different methodologies and thresholds used. Clinical implementation therefore remains a challenge. The role of immune checkpoint inhibitors in gastric cancer is emerging with data from monotherapy in the heavily pre-treated population already available and studies in earlier disease settings with different combinatorial approaches in progress. Immune checkpoint inhibitor combinations with chemotherapy (CT), anti-angiogenics, tyrosine kinase inhibitors, anti-Her2 directed therapy, poly (ADP-ribose) polymerase inhibitors or dual checkpoint inhibitor strategies are being explored. Moreover, novel strategies including vaccines and CAR T cell therapy are also being trialed. Here we provide an update on predictive biomarkers for response to immunotherapy with an overview of their strengths and limitations. We discuss clinical trials that have been reported and trials in progress whilst providing an account of future steps needed to improve outcome in this lethal disease.

Evolving landscape and academic attitudes toward the controversies of global immuno-oncology trials

This cross‐sectional and longitudinal descriptive analysis aimed to track the evolving landscape of global immuno‐oncology (IO) trials and provide insight into the resolution of IO‐related controversies. Clinical trials (n = 4510) registered on ClinicalTrials.gov in 2007 to 2019 studying immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT), cancer vaccines and immune modulators were included. Most of IO trials are Phase 2 and focus on ICIs and multiple IO therapies. The United States leads global IO research, with stable growth and the best methodological quality. Mainland China ranks first in the number of ACT trials but has the lowest article publication rate (6.2%). A multiple‐arm comparative design is often adopted in multiple IO therapies trials (44.0%). Trials studying ICIs and multiple IO therapies are likely to use early registration (80.0% and 86.6%) and stringent corticosteroid‐/infection‐related criteria. Hospitals have provided the most extensive and strongest support for all IO categories. Big pharma prefers to fund Phase 3‐4 ICI trials (6.98%), while small pharma has a wider sponsorship favoring Phase 1‐2 trials. The “partial‐use‐of‐corticosteroids” strategy is generally well accepted in ICI trials with a definitive trend (32.5%; P < .001) but is associated with the poor dissemination of results (P ≤ .020), while the complete disclosure and standardization of dose/timing limits are still lacking. Disparities in design features and dissemination of results are widespread in IO trials and are modulated by IO category, cancer type and sponsor. We propose policy reforms to redefine the timely publication of IO trials and standardize the resolution of corticosteroid‐/infection‐related issues.

What's new?

In recent decades, immunotherapy has emerged and advanced to become a key part of cancer‐fighting strategies. The rapid growth of immuno‐oncology, however, has been accompanied by controversy in suitable interventions and trial design. In this cross‐sectional and longitudinal analysis, disparities in design were found to be common in immuno‐oncology trials, with differences influenced by factors such as cancer type and trial sponsor. Trials with strict limitations on corticosteroid use had significantly higher publications rates than trials permitting partial corticosteroid administration. The data further suggest that timely publication of immuno‐oncology trials is the third year after trial completion.

Immunotherapeutic advances in gastric cancer

Advanced gastric cancers are responsible for overwhelming human suffering and death. Despite the development of combination chemotherapies, the survival rates of patients with gastric cancer remain unsatisfactory. Given the growing evidence of the benefits of immunotherapy as an alternative treatment for other cancers such as advanced melanoma, non-small cell lung cancer, renal cell carcinoma, and refractory Hodgkin's lymphoma, researchers have begun to explore its application in the treatment of gastric cancer. Three types of immunotherapy have shown promising effects against gastric cancer: immune checkpoint inhibitors, chimeric antigen rector (CAR)-T cells, and tumor vaccines. Clinical trials have used either immuno-oncology monotherapies or combination immuno-chemotherapies to improve the overall survival times and objective response rates of patients with gastric cancer. We review the clinical efficacy of immunotherapy including checkpoint inhibitors, CAR‑T, and tumor vaccines, in the treatment of gastric cancer. Based on initial evidence, we believe that immunotherapy could positively impact the natural history and improve the outcomes of a subgroup of patients with gastric cancer.

Combination of vasculature targeting, hypofractionated radiotherapy, and immune checkpoint inhibitor elicits potent antitumor immune response and blocks tumor progression

Background

Tumor endothelial marker 1 (TEM1) is a protein expressed in the tumor-associated endothelium and/or stroma of various types of cancer. We previously demonstrated that immunization with a plasmid-DNA vaccine targeting TEM1 reduced tumor progression in three murine cancer models. Radiation therapy (RT) is an established cancer modality used in more than 50% of patients with solid tumors. RT can induce tumor-associated vasculature injury, triggering immunogenic cell death and inhibition of the irradiated tumor and distant non-irradiated tumor growth (abscopal effect). Combination treatment of RT with TEM1 immunotherapy may complement and augment established immune checkpoint blockade.

Methods

Mice bearing bilateral subcutaneous CT26 colorectal or TC1 lung tumors were treated with a novel heterologous TEM1-based vaccine, in combination with RT, and anti-programmed death-ligand 1 (PD-L1) antibody or combinations of these therapies, tumor growth of irradiated and abscopal tumors was subsequently assessed. Analysis of tumor blood perfusion was evaluated by CD31 staining and Doppler ultrasound imaging. Immunophenotyping of peripheral and tumor-infiltrating immune cells as well as functional analysis was analyzed by flow cytometry, ELISpot assay and adoptive cell transfer (ACT) experiments.

Results

We demonstrate that addition of RT to heterologous TEM1 vaccination reduces progression of CT26 and TC1 irradiated and abscopal distant tumors as compared with either single treatment. Mechanistically, RT increased major histocompatibility complex class I molecule (MHCI) expression on endothelial cells and improved immune recognition of the endothelium by anti-TEM1 T cells with subsequent severe vascular damage as measured by reduced microvascular density and tumor blood perfusion. Heterologous TEM1 vaccine and RT combination therapy boosted tumor-associated antigen (TAA) cross-priming (ie, anti-gp70) and augmented programmed cell death protein 1 (PD-1)/PD-L1 signaling within CT26 tumor. Blocking the PD-1/PD-L1 axis in combination with dual therapy further increased the antitumor effect and gp70-specific immune responses. ACT experiments show that anti-gp70 T cells are required for the antitumor effects of the combination therapy.

Conclusion

Our findings describe novel cooperative mechanisms between heterologous TEM1 vaccination and RT, highlighting the pivotal role that TAA cross-priming plays for an effective antitumor strategy. Furthermore, we provide rationale for using heterologous TEM1 vaccination and RT as an add-on to immune checkpoint blockade as triple combination therapy into early-phase clinical trials.

Nanoenabled Tumor Oxygenation Strategies for Overcoming Hypoxia-Associated Immunosuppression

Cancer immunotherapy, which initiates or strengthens innate immune responses to attack cancer cells, has shown great promise in cancer treatment. However, low immune response impacted by immunosuppressive tumor microenvironment (TME) remains a key challenge, which has been found related to tumor hypoxia. Recently, nanomaterial systems are proving to be excellent platforms for tumor oxygenation, which can reverse hypoxia-associated immunosuppression, strengthen the systemic antitumor immune responses, and thus afford a striking abscopal effect to clear metastatic cancer cells. In this review, we would like to survey recent progress in utilizing nanomaterials for tumor oxygenation through approaches such as in situ O₂ generation, O₂ delivery, tumor vasculature normalization, and mitochondrial-respiration inhibition. Their effects on tumor hypoxia-associated immunosuppression are highlighted. We also discuss the ongoing challenges and how to further improve the clinical prospect of cancer immunotherapy.

Adjuvant incorporated lipid nanoparticles for enhanced mRNA-mediated cancer immunotherapy

For mRNA mediated cancer immunotherapy, Pam3 was incorporated as an adjuvant within lipid nanoparticles (LNPs) with OVA mRNA. The developed Pam3 incorporated LNPs showed successful expression of tumor antigens with enhanced immune stimulation. We demonstrated that the synergies of Pam3 LNPs could greatly improve the efficacy of tumor prevention by mRNA vaccines.

Use of immunotherapy in the treatment of gastric cancer

Gastric cancer (GC) is a malignant tumor that negatively impacts human health, which typically presents in the advanced stages of disease in the majority of patients. Despite the development of combination chemotherapy, only a modest survival advantage is gained in patients with GC treated by this method. Recently, cancer immunotherapies have received considerable attention as a viable therapeutic option for GC. Specifically, the immune checkpoint inhibitors, chimeric antigen rector (CAR)-T cells and tumor vaccines, represent immunotherapies that have exhibited promising effects in the treatment of GC. A number of clinical trials have employed either immuno-oncology monotherapies or combination therapies to improve the overall survival time (OS) and objective response rate (ORR) of patients with GC. The current review presents a summary of the clinical effects of checkpoint inhibitors, including CAR-T and tumor vaccines, in the treatment of GC.

Ongoing and future directions in the management of metastatic colorectal cancer: Update on clinical trials

Metastatic colorectal cancer (mCRC) continues to show poor outcomes, with many patients exhausting effective standard-of-care therapy. To explore the current landscape of clinical trials for mCRC, we reviewed over 600 clinical trials that are currently ongoing for mCRC patients. Immunotherapeutic agents form approximately 39% (includes monoclonal antibodies, viruses, vaccines, and immunomodulators) of all agents and targeted therapy forms 45% (tyrosine kinase inhibitors, epigenetic modulators, and others) of all agents being investigated for mCRC.

Pancreatic adenocarcinomas with mature blood vessels have better overall survival

Pancreatic ductal adenocarcinoma (PDAC) is known for its hypovascularity. Bevacizumab, an anti-angiogenic drug, added to standard chemotherapy demonstrated no improvement in outcome for PDAC. Therefore, we hypothesized that increased vascularity may be associated with improved outcomes in PDAC possibly due to better delivery of tumor specific immune cells. To test this hypothesis, PDAC patients were classified into either high or low CD31 expression groups utilizing mRNA expression from RNA-sequence data in The Cancer Genome Atlas (TCGA) pancreatic cancer cohort. High expression of CD31, which indicates presence of more vascular endothelial cells, was associated with significantly better OS (p = 0.002). Multivariate analysis demonstrated that residual tumor (R1, 2; p = 0.026) and CD31 low expression (p = 0.007) were the only independent predictors that negatively impacted OS. Vascular stability as well as immune response related pathways were significantly upregulated in the CD31 high expressing tumors. Furthermore, there were higher proportions of anti-cancer immune cells infiltration, including activated memory CD4+ T cells (p = 0.038), CD8+ T cells (p = 0.027), gamma-delta T cells (p < 0.001) as well as naïve B cells (p = 0.006), whereas lower proportions of regulatory T cell fractions (p = 0.009), which induce an immune tolerant microenvironment, in the CD31 high expressing tumors. These findings imply that stable vessels supply anti-cancer immune cells, which are at least partially responsible for better OS in the CD31 high expressing tumors. In conclusion, CD31 high expressing PDACs have better OS, which may be due to stable vessels that supply anti-cancer immune cells.

Macrophage Foam Cell-Targeting Immunization Attenuates Atherosclerosis

Background: Macrophage foam cells (FCs) play a crucial role in the initiation and progression of atherosclerosis. Reducing the formation or inducing the removal of FCs could ameliorate atherosclerosis. The present study examined whether the whole-cell vaccination using FCs could be used as novel prevention and treatment strategies to battle atherosclerosis.

Methods: ApoE^−/− mice with initial or established atherosclerosis were subcutaneously immunized three times with FCs in Freund's adjuvant.

Results: Immunization with FCs resulted in an overt reduction of atherosclerotic lesion in the whole aorta and the aortic root with enhanced lesion stability. Subsequent study in mechanism showed that FCs vaccination dramatically increased CD4⁺ T cell and CD8⁺ T cell populations. Immunization with FCs significantly raised the plasma FCs-specific IgG antibodies. Of note, the FCs immune plasma could selectively recognize and bind to FC. FCs immune plasma significantly blocked the process of FCs formation, finally reduced the accumulation of FCs in plaque. Additionally, it was observed that FCs immunization down-regulated the expression level of atherosclerosis related pro-inflammatory cytokines, including IFN-γ, MCP-1, and IL-6 and enhanced the lesion stability with a significant increase in TGF-β1 level and collagen content.

Conclusions: These findings demonstrate that the whole-cell vaccination using FCs significantly decreased lesion development and positively modulated lesion progression and stability by targeting FCs. The whole-cell FCs vaccine might represent a potential novel strategy for development of new antibodies and vaccines to the prevention or treatment of atherosclerosis.

Local biomaterials-assisted cancer immunotherapy to trigger systemic antitumor responses

Cancer immunotherapy by educating or stimulating patients’ own immune systems to attack cancer cells has demonstrated promising therapeutic responses in the clinic.

Optimising Cancer Vaccine Design in Sarcoma

Immunotherapeutics are increasingly recognized as a key tool in the armamentarium against malignancy. The success of immune checkpoint-targeting drugs and adoptive cell therapy has refocused attention on the potential anti-cancer effect of eliciting a tumour-specific immunological response. Sarcomas are a rare and diverse group of tumours with a limited prognosis in advanced disease despite systemic therapeutics. Various vaccine strategies including peptide vaccines against cancer testis antigens, dendritic cell vaccines, and viral vectors have been trialled in sarcoma with growing evidence of efficacy. Here, we review the principles of successful vaccine development and how these have been applied thus far to the treatment of sarcoma.

Large-scale database mining reveals hidden trends and future directions for cancer immunotherapy

Cancer immunotherapy has fundamentally changed the landscape of oncology in recent years and significant resources are invested into immunotherapy research. It is in the interests of researchers and clinicians to identify promising and less promising trends in this field in order to rationally allocate resources. This requires a quantitative large-scale analysis of cancer immunotherapy related databases.

We developed a novel tool for text mining, statistical analysis and data visualization of scientific literature data. We used this tool to analyze 72002 cancer immunotherapy publications and 1469 clinical trials from public databases. All source codes are available under an open access license.

The contribution of specific topics within the cancer immunotherapy field has markedly shifted over the years. We show that the focus is moving from cell-based therapy and vaccination towards checkpoint inhibitors, with these trends reaching statistical significance. Rapidly growing subfields include the combination of chemotherapy with checkpoint blockade. Translational studies have shifted from hematological and skin neoplasms to gastrointestinal and lung cancer and from tumor antigens and angiogenesis to tumor stroma and apoptosis.

This work highlights the importance of unbiased large-scale database mining to assess trends in cancer research and cancer immunotherapy in particular. Researchers, clinicians and funding agencies should be aware of quantitative trends in the immunotherapy field, allocate resources to the most promising areas and find new approaches for currently immature topics.

Cell migration in microengineered tumor environments

Recent advances in microengineered cell migration platforms are discussed critically with a focus on how cell migration is influenced by engineered tumor microenvironments, the medical relevance being to understand how tumor microenvironments may promote or suppress the progression of cancer. We first introduce key findings in cancer cell migration under the influence of the physical environment, which is systematically controlled by microengineering technology, followed by multi-cues of physico-chemical factors, which represent the complexity of the tumor environment. Recognizing that cancer cells constantly communicate not only with each other but also with tumor-associated cells such as vascular, fibroblast, and immune cells, and also with non-cellular components, it follows that cell motility in tumor microenvironments, especially metastasis via the invasion of cancer cells into the extracellular matrix and other tissues, is closely related to the malignancy of cancer-related mortality. Medical relevance of forefront research realized in microfabricated devices, such as single cell sorting based on the analysis of cell migration behavior, may assist personalized theragnostics based on the cell migration phenotype. Furthermore, we urge development of theory and numerical understanding of single or collective cell migration in microengineered platforms to gain new insights in cancer metastasis and in therapeutic strategies.

In Silico Modeling of Immunotherapy and Stroma-Targeting Therapies in Human Colorectal Cancer

Despite the fact that the local immunological microenvironment shapes the prognosis of colorectal cancer, immunotherapy has shown no benefit for the vast majority of colorectal cancer patients. A better understanding of the complex immunological interplay within the microenvironment is required. In this study, we utilized wet lab migration experiments and quantitative histological data of human colorectal cancer tissue samples (n = 20) including tumor cells, lymphocytes, stroma, and necrosis to generate a multiagent spatial model. The resulting data accurately reflected a wide range of situations of successful and failed immune surveillance. Validation of simulated tissue outcomes on an independent set of human colorectal cancer specimens (n = 37) revealed the model recapitulated the spatial layout typically found in human tumors. Stroma slowed down tumor growth in a lymphocyte-deprived environment but promoted immune escape in a lymphocyte-enriched environment. A subgroup of tumors with less stroma and high numbers of immune cells showed high rates of tumor control. These findings were validated using data from colorectal cancer patients (n = 261). Low-density stroma and high lymphocyte levels showed increased overall survival (hazard ratio 0.322, P = 0.0219) as compared with high stroma and high lymphocyte levels. To guide immunotherapy in colorectal cancer, simulation of immunotherapy in preestablished tumors showed that a complex landscape with optimal stroma permeabilization and immune cell activation is able to markedly increase therapy response in silico These results can help guide the rational design of complex therapeutic interventions, which target the colorectal cancer microenvironment. Cancer Res; 77(22); 6442-52. ©2017 AACR.

Is still there a role for IL-2 for solid tumors other than melanoma or renal cancer?

AIM

IL-2 is one of the first immunomodulating cytokines to be tested in the treatment of cancer patients. The effects of this agent in the treatment of solid tumors other than renal cancer and melanoma are poorly understood.

MATERIALS & METHODS

We have carried out a meta-analysis of randomized studies. We fixed the response rate as the primary outcome.

RESULTS

The pooled risk ratio for an objective response with IL-2 plus chemotherapy versus chemotherapy alone was 1.43 (95% CI: 1.12-1.81; p = 0.004), in favor of colorectal cancer.

CONCLUSION

Further investigation in the treatment of patients with colorectal cancer or other solid malignancies with IL-2 is required, alone or in combination with chemotherapy.

Crossing the Blood-Brain Barrier: Recent Advances in Drug Delivery to the Brain

CNS disorders are on the rise despite advancements in our understanding of their pathophysiological mechanisms. A major hurdle to the treatment of these disorders is the blood-brain barrier (BBB), which serves as an arduous janitor to protect the brain. Many drugs are being discovered for CNS disorders, which, however fail to enter the market because of their inability to cross the BBB. This is a pronounced challenge for the pharmaceutical fraternity. Hence, in addition to the discovery of novel entities and drug candidates, scientists are also developing new formulations of existing drugs for brain targeting. Several approaches have been investigated to allow therapeutics to cross the BBB. As the molecular structure of the BBB is better elucidated, several key approaches for brain targeting include physiological transport mechanisms such as adsorptive-mediated transcytosis, inhibition of active efflux pumps, receptor-mediated transport, cell-mediated endocytosis, and the use of peptide vectors. Drug-delivery approaches comprise delivery from microspheres, biodegradable wafers, and colloidal drug-carrier systems (e.g., liposomes, nanoparticles, nanogels, dendrimers, micelles, nanoemulsions, polymersomes, exosomes, and quantum dots). The current review discusses the latest advancements in these approaches, with a major focus on articles published in 2015 and 2016. In addition, we also cover the alternative delivery routes, such as intranasal and convection-enhanced diffusion methods, and disruption of the BBB for brain targeting.

PD-1 checkpoint blockade alone or combined PD-1 and CTLA-4 blockade as immunotherapy for lung cancer?

INTRODUCTION

Signaling through T-cell surface, an immune checkpoint protein such as PD-1 or CTLA-4 helps dampen or terminate unwanted immune responses. Blocking a single immune checkpoint or multiple checkpoints simultaneously can generate anti-tumor activity against a variety of cancers including lung cancer. Area covered: This review highlights the results of recent clinical studies of single or combination checkpoint inhibitor immunotherapy in non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). The authors discuss pembrolizumab and pembrolizumab plus ipilimumab, durvalumab and durvalumab plus tremelimumab, nivolumab and nivolumab plus ipilimumab for NSCLC as well as nivolumab and nivolumab plus ipilimumab for SCLC. Expert opinion: Available data suggest that, in both metastatic NSCLC and SCLC, combined PD-1 and CTLA-4 blockade may produce a higher tumor response rate than PD-1 blockade alone. Nevertheless, combination therapy is associated with an increased toxicity. Several larger-scale studies are currently ongoing. For checkpoint inhibitor immunotherapy in SCLC and NSCLC, combination therapy is associated with a higher incidence of toxicities than single therapy; however, it appears to help increase tumor response rate. The increased response rate, if confirmed in larger scale studies, will likely make combination therapy another useful therapeutic approach for lung cancer.

Metastatic melanoma and immunotherapy

Harnessing the immune system to attack cancer cells has represented a holy grail for greater than 100years. While prospects of tumor-selective durable immune based therapies have provided small clinical signals for many decades, recent years have demonstrated a virtual explosion in progress. Melanoma has led the field of cancers in which immunotherapy has produced major clinical inroads. The most significant and impactful immunotherapies for melanoma utilize immune checkpoint inhibition to stimulate T cell mediated tumor killing. The major targets of checkpoint blockade have thus far been CTLA4 and PD1, two key receptors for central and peripheral immune tolerance. This review discusses current understanding of how these checkpoint blockade therapeutics have led to major clinical responses in patients with advanced melanoma. It is likely that we are poised to see significantly greater anti-cancer immunotherapy efficacy, both in improving response rates and durability for melanoma, and for other less immunogenic malignancies.

Addition of CpG ODN and Poly (I:C) to a standard maturation cocktail generates monocyte-derived dendritic cells and induces a potent Th1 polarization with migratory capacity

Monocyte-derived dendritic cells (DCs) are used as immunoadjuvant cells in cancer vaccines and have made great progress. However, an optimal DCs subset is vital for this treatment effect, the current 'gold standard' cytokine cocktail DCs have a shortcoming in their cytokines secretion, especially IL-12p70, mainly because of the existence of PGE2. Therefore, it is necessary to find an appropriate DCs-based immunotherapeutic protocol. In this study, we compared a novel 'improved' maturation cytokine cocktail with the current 'gold standard' maturation cytokine cocktail used for generating standard DCs. The 'improved' maturation cytokine cocktail DCs showed a higher levels surface markers expression (CD80, CD83, CD86 and HLA-DR), the chemokine receptors CXCR4 and CCR7 and chemokine CCL19, CCL21 and CXCL21, whereas CCR5 expression was reduced. Most importantly, in contrast to 'gold standard' DCs, which secrete little IL-12p70 and as a result induce mainly Th2 immunity, 'improved' cytokine cocktail DCs secreted higher levels IL-12p70 and also secreted similar concentration IL-10. To removal of PGE2 from the 'improved' DCs did increase the IL-12p70 production. In conclusion, we here present the 'improved' DCs, as an optimal maturation cocktail protocol, can induce high migratory potential, generate immunostimulatory DCs, produce higher levels IL-12p70 with superior capacity to induce Th1 immunity, when compared with the 'gold standard' DCs.

Prospective immunotherapies in childhood sarcomas: PD1/PDL1 blockade in combination with tumor vaccines

Progress has slowed substantially in improving survival rates for pediatric sarcomas, particularly in refractory and metastatic disease. Significant progress has been made in the field of tumor vaccines for such malignancies, which target established tumor antigens. While tumor vaccines have demonstrated safety and improved survival rates, they are inadequate in mediating the regression of established tumor masses and metastases. Programmed cell death ligand 1 (PDL1) is a cell-surface protein induced in a number of adult malignancies. By acting on the corresponding T-cell receptor PD1, PDL1 is able to suppress cytotoxic T-cell-mediated tumor responses. Recent therapeutics blocking this interaction have shown promise in various adult cancers by restoring a functional T-cell response and by directing this response toward an activated, rather than regulatory, T-cell phenotype. We shall discuss the current state of tumor vaccines targeting pediatric sarcomas, review PD1-PDL1 interactions and current therapies targeting these interactions in adult malignancies, and discuss recent studies in which tumor vaccines, combined with PDL1 blockades, produced superior tumor regression compared with the vaccine alone. These studies provide a compelling case for investigation of PDL1 expression and its inhibition in pediatric sarcomas, while continuing to utilize tumor vaccines in tandem to achieve superior clinical outcomes.

Functionalized graphene oxide serves as a novel vaccine nano-adjuvant for robust stimulation of cellular immunity

Benefiting from their unique physicochemical properties, graphene derivatives have attracted great attention in biomedicine. In this study, we carefully engineered graphene oxide (GO) as a vaccine adjuvant for immunotherapy using urease B (Ure B) as the model antigen. Ure B is a specific antigen for Helicobacter pylori, which is a class I carcinogen for gastric cancer. Polyethylene glycol (PEG) and various types of polyethylenimine (PEI) were used as coating polymers. Compared with single-polymer modified GOs (GO-PEG and GO-PEI), certain dual-polymer modified GOs (GO-PEG-PEI) can act as a positive modulator to promote the maturation of dendritic cells (DCs) and enhance their cytokine secretion through the activation of multiple toll-like receptor (TLR) pathways while showing low toxicity. Moreover, this GO-PEG-PEI can serve as an antigen carrier to effectively shuttle antigens into DCs. These two advantages enable GO-PEG-PEI to serve as a novel vaccine adjuvant. In the subsequent in vivo experiments, compared with free Ure B and clinically used aluminum-adjuvant-based vaccine (Alum-Ure B), GO-PEG-PEI-Ure B induces stronger cellular immunity via intradermal administration, suggesting promising applications in cancer immunotherapy. Our work not only presents a novel, highly effective GO-based vaccine nano-adjuvant, but also highlights the critical roles of surface chemistry for the rational design of nano-adjuvants.

Emerging nanomedicine approaches fighting tumor metastasis: animal models, metastasis-targeted drug delivery, phototherapy, and immunotherapy

Nanomedicine approaches may bring new opportunities for tumor metastasis treatment.

2015 Guidance on cancer immunotherapy development in early-phase clinical studies

The development of cancer immunotherapies is progressing rapidly with a variety of technological approaches. They consist of "cancer vaccines", which are based on the idea of vaccination, "effector cell therapy", classified as passive immunotherapy, and "inhibition of immunosuppression", which intends to break immunological tolerance to autoantigens or immunosuppressive environments characterizing antitumor immune responses. Recent reports showing clinical evidence of efficacy of immune checkpoint inhibitors and adoptive immunotherapies with tumor-infiltrating lymphocytes and tumor-specific receptor gene-modified T cells indicate the beginning of a new era for cancer immunotherapy. This guidance summarizes ideas that will be helpful to those who plan to develop cancer immunotherapy. The aims of this guidance are to discuss and offer important points in early phase clinical studies of innovative cancer immunotherapy, with future progress in this field, and to contribute to the effective development of cancer immunotherapy aligned with the scope of regulatory science. This guidance covers cancer vaccines, effector cell therapy, and inhibition of immunosuppression, including immune checkpoint inhibitors.

Improved anti-glioblastoma efficacy by IL-13Rα2 mediated copolymer nanoparticles loaded with paclitaxel

Glioma presents one of the most malignant brain tumors, and the therapeutic effect is often limited due to the existence of brain tumor barrier. Based on interleukin-13 receptor α2 (IL-13Rα2) over-expression on glioma cell, it was demonstrated to be a potential receptor for glioma targeting. In this study, Pep-1-conjugated PEGylated nanoparticles loaded with paclitaxel (Pep-NP-PTX) were developed as a targeting drug delivery system for glioma treatment. The Pep-NP-PTX presented satisfactory size of 95.78 nm with narrow size distribution. Compared with NP-PTX, Pep-NP-PTX exhibited significantly enhanced cellular uptake in C6 cells (p < 0.001). The in vitro anti-proliferation evaluation showed that the IC50 were 146 ng/ml and 349 ng/ml of Pep-NP-PTX and NP-PTX, respectively. The in vivo fluorescent image results indicated that Pep-NP had higher specificity and efficiency in intracranial tumor accumulation. Following intravenous administration, Pep-NP-PTX could enhance the distribution of PTX in vivo glioma section, 1.98, 1.91 and 1.53-fold over that of NP-PTX group after 0.5, 1 and 4 h, respectively. Pep-NP-PTX could improve the anti-glioma efficacy with a median survival time of 32 days, which was significantly longer than that of PTX-NP (23 days) and Taxol(®) (22 days). In conclusion, Pep-NP-PTX is a potential targeting drug delivery system for glioma treatment.

Can dendritic cells improve whole cancer cell vaccines based on immunogenically killed cancer cells?

Immunogenic cell death (ICD) offers interesting opportunities in cancer cell (CC) vaccine manufacture, as it increases the immunogenicity of the dead CC. Furthermore, fusion of CCs with dendritic cells (DCs) is considered a superior method for generating whole CC vaccines. Therefore, in this work, we determined in naive mice whether immunogenically killed CCs per se (CC vaccine) elicit an antitumoral immune response different from the response observed when immunogenically killed CCs are associated with DCs through fusion (fusion vaccine) or through co-incubation (co-incubation vaccine). After tumor inoculation, the type of immune response in the prophylactically vaccinated mice differed between the groups. In more detail, fusion vaccines elicited a humoral anticancer response, whereas the co-incubation and CC vaccine mainly induced a cellular response. Despite these differences, all three approaches offered a prophylactic protection against tumor development in the murine mammary carcinoma model. In summary, it can be concluded that whole CC vaccines based on immunogenically killed CCs may not necessarily require association with DCs to elicit a protective anticancer immune response. If this finding can be endorsed in other cancer models, the manufacture of CC vaccines would greatly benefit from this new insight, as production of DC-based vaccines is laborious, time-consuming and expensive.

Survivin and PSMA Loaded Dendritic Cell Vaccine for the Treatment of Prostate Cancer

Dendritic cell (DC)-based vaccines are a promising therapeutic modality for cancer. Results from recent trials and approval of the first DC vaccine by the U.S. Food and Drugs Administration for prostate cancer have paved the way for DC-based vaccines. A total of 21 hormone refractory prostate cancer (HRPC) patients with a life expectancy >3 months were randomised into two groups. DC loaded with recombinant Prostate Specific Membrane Antigen (rPSMA) and recombinant Survivin (rSurvivin) peptides was administered as an subcutaneous (s.c.) injection (5×10(6) cells). Docetaxel (75 mg/m(2) intravenous (i.v.)) and prednisone (5 mg, bis in die (b.i.d.)) served as control. Clinical and immunological responses were evaluated. Primary endpoints were safety and feasibility; secondary endpoint was overall survival. Responses were evaluated on day 15, day 30, day 60, and day 90. DC vaccination was well tolerated with no signs of grade 2 toxicity. DC vaccination induced delayed-type hypersensitivity reactivity and an immune response in all patients. Objective Response Rate (ORR) by Response Evaluation Criteria in Solid Tumours (RECIST) was 72.7% (8/11) versus 45.4 (5/11) in the docetaxel arm and immune related response criteria (irRC) was 54.5% (6/11) compared with 27.2% (3/11) in the control arm. The DC arm showed stable disease (SD) in 6 patients, progressive disease (PD) in 3 patients, and partial remission (PR) in two patients compared to SD in 5 patients, PD in 6 patients, and PR in none in the docetaxel arm. There was a cellular response, disease stabilization, no adverse events, and partial remission with the rPSMA and rSurvivin primed DC vaccine.

Anti-PD-1 therapy in melanoma

Immune-regulatory mechanisms are used by cancer to hide from the immune system. Advances and in-depth understanding of the biology of melanoma and its interaction with the immune system have led to the development of some of antagonistic antibodies to the programmed death 1 pathway (PD-1) and one of its ligands, programmed death ligand 1 (PD-L1), which are demonstrating high clinical benefit rates and tolerability. Blocking the immune-regulatory checkpoints that limit T-cell responses to melanoma upon PD-1/PD-L1 modulation has provided clinically validated targets for cancer immunotherapy. Combinations with other anti-melanoma agents may result in additional benefits. Nivolumab, pembrolizumab (formerly known as MK-3475 and lambrolizumab), and pidilizumab are anti-PD-1 antibodies in clinical development for melanoma, non-small cell lung cancer, renal cell carcinoma, head and neck cancers, lymphoma, and several other cancers. Long-term survivors already have been reported with these therapies. In this review, we discuss the current state of anti-PD-1 agents, the evidence in the literature to support the combination of anti-PD-1 antibodies with other anti-cancer agents and discuss the future directions for rational design of clinical trials that keep on increasing the number of long-term survivors.

Hapten-enhanced therapeutic effect in advanced stages of lung cancer by ultra-minimum incision personalized intratumoral chemoimmunotherapy therapy

Aim

The objective of the study reported here was to evaluate the therapeutic effects of hapten-enhanced chemoimmunotherapy in the treatment of advanced lung cancer by ultra-minimum incision personalized intratumoral chemoimmunotherapy (UMIPIC) and to analyze the effect of this immune booster.

Materials and methods

A total of 97 patients with advanced lung cancer were treated with UMIPIC or intratumoral chemotherapy (ITCT). UMIPIC was delivered intratumorally in combination with a proprietary therapeutic regimen composed of three components – an oxidant, a cytotoxic drug, and hapten. ITCT applied using the same procedures and regimen, only without hapten. All data from the two groups were reviewed and analyzed. A total of 55 patients were treated with UMIPIC and 42 with ITCT. Patient responses were assessed with computed tomography scan 4–6 weeks after treatment, and all of the patients were followed until their deaths.

Results

Median overall survival was 11.23 months in the UMIPIC (test) group and 5.62 months in the ITCT (control) group (P<0.01). The 6-month and 1-year survival rates of the UMIPIC and ITCT groups were 76.36% versus 45.23% (P<0.01) and 45.45% versus 23.81% (P<0.05), respectively. Two cycles of UMIPIC treatment (n=19) conferred a significant survival benefit compared with two cycles of ITCT (n=29); significant benefits in survival time were also found with UMIPIC (n=20) compared with ITCT (n=13) when both were utilized without adjuvant treatment.

Conclusion

The hapten-enhanced clinical effect of UMIPIC conferred a superior survival time in patients with advanced lung cancer compared with ITCT. The addition of the hapten in UMIPIC demonstrates a significant advantage in terms of prolonged survival time.

Cancer vaccines: Looking to the future

These are exciting times for the field of cancer immunotherapy. Although the clinical efficacy of monoclonal antibodies has been demonstrated since the early 1990s, the therapeutic profile of other immunotherapeutic approaches-especially vaccines-has not yet been formally clarified. However, the recent success of several immunotherapeutic regimens in cancer patients has boosted the development of this treatment modality. These achievements stemmed from recent scientific advances demonstrating the tolerogenic nature of cancer and the fundamental role of the tumor immune microenvironment in the suppression of antitumor immunity. New immunotherapeutic strategies against cancer attempt to promote protective antitumor immunity while disrupting the immunoregulatory circuits that contribute to tumor tolerance. Cancer vaccines differ from other anticancer immunotherapeutics in that they initiate the dynamic process of activating the immune system so as to successfully re-establish a state of equilibrium between tumor cells and the host. This article reviews recent clinical trials involving several different cancer vaccines and describes some of the most promising immunotherapeutic approaches that harness antitumor T-cell responses. In addition, we describe strategies whereby cancer vaccines can be exploited in combination with other therapeutic approach to overcome-in a synergistic fashion-tumor immunoevasion. Finally, we discuss prospects for the future development of broad spectrum prophylactic anticancer vaccines.

The optimal partnership of radiation and immunotherapy: from preclinical studies to clinical translation

The main role of the immune system is to restore tissue homeostasis when altered by pathogenic processes, including neoplastic transformation. Immune-mediated tumor rejection has been recognized as an extrinsic tumor suppressor mechanism that tumors need to overcome to progress. By the time a tumor becomes clinically apparent it has successfully escaped immune control by establishing an immunosuppressive microenvironment. Ionizing radiation applied locally to a tumor alters these tumor-host interactions. Accumulating evidence indicates that standard therapeutic doses of radiation have the potential to recover tumor immunogenicity and convert the tumor into an in situ personalized vaccine. Radiotherapy induces an immunogenic tumor cell death promoting cross-presentation of tumor-derived antigens by dendritic cells to T cells. In addition, radiotherapy stimulates chemokine-mediated recruitment of effector T cells to the tumor, and cellular recognition and killing by T cells that is facilitated by upregulation of major histocompatibility antigens, NKG2D ligands, adhesion molecules and death receptors. Despite these effects, radiotherapy alone is only rarely capable of generating enough proinflammatory signals to sufficiently overcome suppression, as it can also activate immunosuppressive factors. However, our group and others have shown that when combined with targeted immunotherapy agents radiotherapy significantly contributes to a therapeutically effective anti-tumor immune response. To illustrate this partnership between radiation and immunotherapy we will discuss as an example our experience in preclinical models and the molecular mechanisms identified. Additionally, the clinical translation of these combinations will be discussed.

Considerations for non-clinical safety studies of therapeutic peptide vaccines

Guidelines for non-clinical studies of prophylactic vaccines against infectious diseases have been published widely, but similar guidelines for therapeutic vaccines, and especially therapeutic peptide vaccines, have yet to be established. The approach to non-clinical safety studies required for therapeutic vaccines differs from that for prophylactic vaccines due to differences in the risk-benefit balance and the mechanisms of action. We propose the following guidelines for non-clinical safety studies for therapeutic peptide vaccines. (i) Since the main safety concern is related to the immune response that might occur at normal sites that express a target antigen, identification of these possible target sites using in silico human expression data is important. (ii) Due to the strong dependence on HLA, it is not feasible to replicate immune responses in animals. Thus, the required non-clinical safety studies are characterized as those detecting off-target toxicity rather than on-target toxicity.

Various ways to improve whole cancer cell vaccines

Immunotherapy based on whole cancer cell vaccines is regarded as a promising avenue for cancer treatment. However, limited efficacy in the first human clinical trials calls for more optimized whole cancer cell vaccines and better patient selection. It is suggested that whole cancer cell vaccines consist preferably of immunogenically killed autologous cancer stem cells associated with dendritic cells. Adjuvants should stimulate both immune effector cells and memory cells, which could be achieved through their correct dosage and timing of administration. There are indications that whole cancer cell vaccination is less effective in patients who are immunocompromised, who have specific genetic defects in their immune or cancer cells, as well as in patients in an advanced cancer stage. However, such patients form the bulk of enrolled patients in clinical trials, prohibiting an objective evaluation of the true potential of whole cancer cell immunotherapy. Each key point will be discussed.

The state of the art in non-small cell lung cancer immunotherapy

Once considered an ineffective modality in lung cancer, immunotherapy has emerged as one of the most promising therapeutic strategies for this lethal disease. The past few years have seen a plethora of clinical trials evaluating various immunotherapeutic approaches in lung cancer. This article discusses the current status of immunotherapy in non-small cell lung cancer with a review of completed studies and ongoing trials.

Radiation for Awakening the Dormant Immune System, a Promising Challenge to be Explored

Recent advances that have been made in our understanding of cancer biology and immunology show that infiltrated immune cells and cytokines in the tumor microenvironment may play different functions that appear tightly related to clinical outcomes. Strategies aimed at interfering with the cross-talk between microenvironment tumor cells and their cellular partners have been considered for the development of new immunotherapies. These novel therapies target different cell components of the tumor microenvironment and importantly, they may be coupled and boosted with classical treatments, such as radiotherapy. In this work, we try to summarize recent data on the microenvironment impact of radiation therapy, from pre-clinical research to the clinic, while taking into account that this new knowledge will probably translate into indication and objective of radiation therapy changes in the next future.