Combinations of Immunotherapy and Radiation in Cancer Therapy (original) (raw)
Related papers
Frontiers in pharmacology, 2018
Since the approval of anti-CTLA4 therapy (ipilimumab) for late-stage melanoma in 2011, the development of anticancer immunotherapy agents has thrived. The success of many immune-checkpoint inhibitors has drastically changed the landscape of cancer treatment. For some types of cancer, monotherapy for targeting immune checkpoint pathways has proven more effective than traditional therapies, and combining immunotherapy with current treatment strategies may yield even better outcomes. Numerous preclinical studies have suggested that combining immunotherapy with radiotherapy could be a promising strategy for synergistic enhancement of treatment efficacy. Radiation delivered to the tumor site affects both tumor cells and surrounding stromal cells. Radiation-induced cancer cell damage exposes tumor-specific antigens that make them visible to immune surveillance and promotes the priming and activation of cytotoxic T cells. Radiation-induced modulation of the tumor microenvironment may also ...
Oncology (Williston Park, N.Y.), 2008
The combination of radiation therapy and immunotherapy holds particular promise as a strategy for cancer therapeutics. Evidence suggests that immunotherapy is most beneficial alone when employed early in the disease process or in combination with standard therapies (eg, radiation) later in the disease process. Indeed, radiation may act synergistically with immunotherapy to enhance immune responses, inhibit immunosuppression, and/or alter the phenotype of tumor cells, thus rendering them more susceptible to immune-mediated killing. As monotherapies, both immunotherapy and radiation may be insufficient to eliminate tumor masses. However, following immunization with a cancer vaccine, the destruction of even a small percentage of tumor cells by radiation could result in crosspriming and presentation of tumor antigens to the immune system, thereby potentiating antitumor responses. Learning how to exploit radiation-induced changes to tumor-cell antigens, and how to induce effective immune...
Frontiers in Immunology
Radiation therapy has been used for many years to treat tumors based on its DNA-damage-mediated ability to kill cells. More recently, RT has been shown to exert beneficial modulatory effects on immune responses, such as triggering immunogenic cell death, enhancing antigen presentation, and activating cytotoxic T cells. Consequently, combining radiation therapy with immunotherapy represents an important area of research. Thus far, immune-checkpoint inhibitors targeting programmed death-ligand 1 (PD-L1), programmed cell death protein 1 (PD-1), and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) have been the focus of many research studies and clinical trials. The available data suggest that such immunotherapies are enhanced when combined with radiation therapy. However, treatment resistance, intrinsic or acquired, is still prevalent. Various theories as to how to enhance these combination therapies to overcome treatment resistance have been proposed. In this review, we focus on the principles surrounding radiation therapy's positive and negative effects on the tumor microenvironment. We explore mechanisms underlying radiation therapy's synergistic and antagonistic effects on immune responses and provide a base of knowledge for radio-immunology combination therapies to overcome treatment resistance. We provide evidence for targeting regulatory T cells, tumor-associated macrophages, and cancer-associated fibroblasts in combination radio-immunotherapies to improve cancer treatment.
Radiation therapy and immunotherapy—a potential combination in cancer treatment
Current Oncology
BackgroundRadiation therapy (rt) is a longstanding treatment modality for cancer. In addition, immune checkpoint blockade has been a significant development in the field of immunotherapy, modifying key immunosuppressive pathways of cancer cells.MethodsThe aim of the present work was to review current concepts of rt and immunotherapy synergism, the abscopal effect, and the molecular effects of rt in the tumour microenvironment, its influence on immune stimulation, and potential clinical outcomes that might evolve from ongoing studies. We also discuss potential predictors of clinical response.ResultsUp-to-date literature concerning the mechanisms, interactions, and latest knowledge about rt and immunotherapy was reviewed and summarized, and is presented here.ConclusionsThe possibility of using hyperfractionated rt to combine an abscopal effect with the enhanced effect of immune treatment using checkpoint blockade is a very promising method for future tumour treatments.
Harnessing the potential of radiation-induced immune modulation for cancer therapy
Cancer immunology research, 2013
The conventional use of radiotherapy is for local tumor control. Radiotherapy of the primary tumor can prevent the development of distant metastases, but this modality is generally not effective for treating preexisting systemic disease. However, radiation-induced tumor destruction may be considered a novel strategy for in situ cancer vaccination, in which tumor antigens released from dying tumor cells may be presented in an immunostimulatory context. Moreover, radiation has been demonstrated to induce immunogenic modulation in various tumor types by altering the biology of surviving cells to render them more susceptible to T cell-mediated killing. Finally, radiotherapy typically has a favorable toxicity profile and is associated with the absence of systemic immunosuppression. Together, these properties suggest that radiotherapy may serve as an important component of combinatorial immunotherapies aimed at augmenting systemic antitumor immunity. Here, we provide an overview of the ra...
The future of radiotherapy and immunotherapy concomitantly in cancer management
Medical Journal of Indonesia, 2019
Immunotherapy is a developing field in cancer treatment. Immunotherapy using immune checkpoint inhibitors has been successful in treating patients with metastatic disease, as well as patients who are refractory to standard treatments. Although immunotherapy has yielded considerably positive outcomes, its clinical benefits are limited to a small subset of patients. A combination of radiotherapy and immunotherapy has been shown to provide greater clinical benefits to more patients. Radiation, particularly hypofractionated radiation with stereotactic radiosurgery or stereotactic body radiotherapy, works by priming T cells, upregulating proinflammatory chemokines, and increasing the immunogenicity of tumor cells. Tumor cells develop immunosuppressive mechanisms that protect them from attack by the immune system. Immunotherapy works by disrupting the ability of tumor cells to setup these defenses. When combined with radiotherapy, it can synergistically enhance tumor cell death via cytoto...
Strategies for combining immunotherapy with radiation for anticancer therapy
Immunotherapy, 2015
Radiation therapy controls local disease but also prompts the release of tumor-associated antigens and stress-related danger signals that primes T cells to promote tumor regression at unirradiated sites known as the abscopal effect. This may be enhanced by blocking inhibitory immune signals that modulate immune activity through a variety of mechanisms. Indeed, abscopal responses have occurred in patients with lung cancer or melanoma when given anti-CTLA4 antibody and radiation. Other approaches involve expanding and reinfusing T or NK cells or engineered T cells to express receptors that target specific tumor peptides. These approaches may be useful for immunocompromised patients receiving radiation. Preclinical and clinical studies are testing both immune checkpoint-based strategies and adoptive immunotherapies with radiation.
Communications biology, 2021
A major obstacle to immunotherapy is insufficient infiltration of effector immune cells into the tumor microenvironment. Radiotherapy greatly reduces tumor burden but relapses often occur. Here we show that the immunosuppressive tumor microenvironment was gradually established by recruiting Tregs after radiation. Despite tumors being controlled after depletion of Tregs in the irradiated area, improvement of mice survival remained poor. A much better antitumor effect was achieved with vaccination followed by radiation than other treatments. Vaccination followed by radiation recruited more effector T cells in tumor regions, which responded to high levels of chemokines. Sequential combination of vaccination and radiotherapy could elicit distinct host immune responses. Our study demonstrated that optimal combination of irradiation and vaccination is required to achieve effective antitumor immune responses. We propose a combination regimen that could be easily translated into the clinic and offer an opportunity for rational combination therapies design in cancer treatment.
Combining radiation and immunotherapy for synergistic antitumor therapy
Current Opinion in Molecular Therapeutics, 2009
The combination of radiation therapy and immunotherapy holds enticing promise as a strategy for cancer treatment. Preclinical studies have shown that radiation may act synergistically with immunotherapy to enhance or broaden antitumor immune responses, in part due to radiation-induced phenotypic alterations of tumor cells that render them more susceptible to immune-mediated killing. Clinical trials employing the combination of therapeutic vaccines with radiation have confirmed many of these findings, and clinical endpoint human studies are both ongoing and planned. This review examines a) the evidence that radiation induces immunologic death, b) the mechanisms by which radiation therapy can induce or augment antitumor immune responses, and c) translational studies demonstrating that immunotherapy can be effectively combined with radiation therapy. Finally, we review recent and current clinical trials combining radiation therapy with immunotherapy.
Immunologically augmented cancer treatment using modern radiotherapy
Radiation oncology has recently seen tremendous technical advances, resulting in increasing cancer cures. However, malignant neoplasias are systemic diseases and may be lethal even with an excellent tumor local control. Immune therapy has grown to a mature approach in oncology, delivering results impossible only a few years ago. Treatment-limiting mechanisms such as the immune suppressive tumor microenvironment are now to a large extent deciphered, allowing for pharmacological intervention. Interestingly, radiation-based treatment effects have been shown to depend to a large degree on the immune system. Applying the recent advances in radiation therapy in conjunction with immune therapy can be a turning point towards the long-standing aim of curing cancer. Only a detailed understanding of the molecular mechanisms can guide the implementation of combined therapy modalities.