1
|
Santiago-Sánchez GS, Fabian KP, Hodge JW. A landscape of checkpoint blockade resistance in cancer: underlying mechanisms and current strategies to overcome resistance. Cancer Biol Ther 2024; 25:2308097. [PMID: 38306161 PMCID: PMC10841019 DOI: 10.1080/15384047.2024.2308097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 01/17/2024] [Indexed: 02/03/2024] Open
Abstract
The discovery of immune checkpoints and the development of immune checkpoint inhibitors (ICI) have achieved a durable response in advanced-stage cancer patients. However, there is still a high proportion of patients who do not benefit from ICI therapy due to a lack of response when first treated (primary resistance) or detection of disease progression months after objective response is observed (acquired resistance). Here, we review the current FDA-approved ICI for the treatment of certain solid malignancies, evaluate the contrasting responses to checkpoint blockade in different cancer types, explore the known mechanisms associated with checkpoint blockade resistance (CBR), and assess current strategies in the field that seek to overcome these mechanisms. In order to improve current therapies and develop new ones, the immunotherapy field still has an unmet need in identifying other molecules that act as immune checkpoints, and uncovering other mechanisms that promote CBR.
Collapse
Affiliation(s)
- Ginette S. Santiago-Sánchez
- Center for Immuno-Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Kellsye P. Fabian
- Center for Immuno-Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - James W. Hodge
- Center for Immuno-Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
2
|
Piovesan D, de Groot AE, Cho S, Anderson AE, Ray RD, Patnaik A, Foster PG, Mitchell CG, Lopez Espinoza AY, Zhu WS, Stagnaro CE, Singh H, Zhao X, Seitz L, Walker NP, Walters MJ, Sivick KE. Fc-Silent Anti-TIGIT Antibodies Potentiate Antitumor Immunity without Depleting Regulatory T Cells. Cancer Res 2024; 84:1978-1995. [PMID: 38635895 DOI: 10.1158/0008-5472.can-23-2455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 02/02/2024] [Accepted: 04/02/2024] [Indexed: 04/20/2024]
Abstract
T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is an inhibitory receptor on immune cells that outcompetes an activating receptor, CD226, for shared ligands. Tumor-infiltrating lymphocytes express TIGIT and CD226 on regulatory T cells (Treg) and on CD8+ T cells with tumor-reactive or exhausted phenotypes, supporting the potential of therapeutically targeting TIGIT to enhance antitumor immunity. To optimize the efficacy of therapeutic antibodies against TIGIT, it is necessary to understand IgG Fc (Fcγ) receptor binding for therapeutic benefit. In this study, we showed that combining Fc-enabled (Fce) or Fc-silent (Fcs) anti-TIGIT with antiprogrammed cell death protein 1 in mice resulted in enhanced control of tumors by differential mechanisms: Fce anti-TIGIT promoted the depletion of intratumoral Treg, whereas Fcs anti-TIGIT did not. Despite leaving Treg numbers intact, Fcs anti-TIGIT potentiated the activation of tumor-specific exhausted CD8+ populations in a lymph node-dependent manner. Fce anti-TIGIT induced antibody-dependent cell-mediated cytotoxicity against human Treg in vitro, and significant decreases in Treg were measured in the peripheral blood of patients with phase I solid tumor cancer treated with Fce anti-TIGIT. In contrast, Fcs anti-TIGIT did not deplete human Treg in vitro and was associated with anecdotal objective clinical responses in two patients with phase I solid tumor cancer whose peripheral Treg frequencies remained stable on treatment. Collectively, these data provide evidence for pharmacologic activity and antitumor efficacy of anti-TIGIT antibodies lacking the ability to engage Fcγ receptor. SIGNIFICANCE Fcs-silent anti-TIGIT antibodies enhance the activation of tumor-specific pre-exhausted T cells and promote antitumor efficacy without depleting T regulatory cells.
Collapse
|
3
|
Ferencz B, Török K, Pipek O, Fillinger J, Csende K, Lantos A, Černeková R, Mitták M, Škarda J, Delongová P, Megyesfalvi E, Schelch K, Lang C, Solta A, Boettiger K, Brcic L, Lindenmann J, Rényi-Vámos F, Aigner C, Berta J, Megyesfalvi Z, Döme B. Expression patterns of novel immunotherapy targets in intermediate- and high-grade lung neuroendocrine neoplasms. Cancer Immunol Immunother 2024; 73:114. [PMID: 38693435 PMCID: PMC11063022 DOI: 10.1007/s00262-024-03704-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 04/14/2024] [Indexed: 05/03/2024]
Abstract
BACKGROUND Advancements in immunotherapeutic approaches only had a modest impact on the therapy of lung neuroendocrine neoplasms (LNENs). Our multicenter study aimed to investigate the expression patterns of novel immunotherapy targets in intermediate- and high-grade LNENs. METHODS The expressions of V-domain Ig suppressor of T cell activation (VISTA), OX40L, Glucocorticoid-induced TNF receptor (GITR), and T cell immunoglobulin and mucin domain 3 (TIM3) proteins were measured by immunohistochemistry in surgically resected tumor samples of 26 atypical carcinoid (AC), 49 large cell neuroendocrine lung cancer (LCNEC), and 66 small cell lung cancer (SCLC) patients. Tumor and immune cells were separately scored. RESULTS Tumor cell TIM3 expression was the highest in ACs (p < 0.001), whereas elevated tumor cell GITR levels were characteristic for both ACs and SCLCs (p < 0.001 and p = 0.011, respectively). OX40L expression of tumor cells was considerably lower in ACs (vs. SCLCs; p < 0.001). Tumor cell VISTA expression was consistently low in LNENs, with no significant differences across histological subtypes. ACs were the least immunogenic tumors concerning immune cell abundance (p < 0.001). Immune cell VISTA and GITR expressions were also significantly lower in these intermediate-grade malignancies than in SCLCs or in LCNECs. Immune cell TIM3 and GITR expressions were associated with borderline prognostic significance in our multivariate model (p = 0.057 and p = 0.071, respectively). CONCLUSIONS LNEN subtypes have characteristic and widely divergent VISTA, OX40L, GITR, and TIM3 protein expressions. By shedding light on the different expression patterns of these immunotherapy targets, the current multicenter study provides support for the future implementation of novel immunotherapeutic approaches.
Collapse
Affiliation(s)
- Bence Ferencz
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Klára Török
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Orsolya Pipek
- Department of Physics of Complex Systems, Eotvos Lorand University, Budapest, Hungary
| | - János Fillinger
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Kristóf Csende
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
| | - András Lantos
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Radoslava Černeková
- Department of Pulmonary Diseases and Tuberculosis, University Hospital Ostrava and Faculty of Medicine, University of Ostrava, Ostrava, Czech Republic
| | - Marcel Mitták
- Surgical Clinic, University Hospital Ostrava and Faculty of Medicine, University of Ostrava, Ostrava, Czech Republic
| | - Jozef Škarda
- Medical Faculty, Institute of Clinical and Molecular Pathology, Palacky University Olomouc, Olomouc, Czech Republic
- Department of Pathology, University Hospital Ostrava and Faculty of Medicine, University of Ostrava, Ostrava, Czech Republic
| | - Patricie Delongová
- Department of Pathology, University Hospital Ostrava and Faculty of Medicine, University of Ostrava, Ostrava, Czech Republic
| | - Evelyn Megyesfalvi
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
- Department of Clinical Pharmacology, National Institute of Oncology, Chest and Abdominal Tumors Chemotherapy "B", Budapest, Hungary
| | - Karin Schelch
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Center for Cancer Research, Medical University of Vienna, Vienna, Austria
| | - Christian Lang
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Division of Pulmonology, Department of Medicine II, Medical University of Vienna, Vienna, Austria
| | - Anna Solta
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Kristiina Boettiger
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Luka Brcic
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Jörg Lindenmann
- Division of Thoracic and Hyperbaric Surgery, Department of Surgery, Medical University of Graz, Graz, Austria
| | - Ferenc Rényi-Vámos
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
- National Koranyi Institute of Pulmonology, Budapest, Hungary
- National Institute of Oncology and National Tumor Biology Laboratory, Budapest, Hungary
| | - Clemens Aigner
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Judit Berta
- National Koranyi Institute of Pulmonology, Budapest, Hungary.
| | - Zsolt Megyesfalvi
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
- National Koranyi Institute of Pulmonology, Budapest, Hungary
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Balázs Döme
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.
- National Koranyi Institute of Pulmonology, Budapest, Hungary.
- Department of Thoracic Surgery, Comprehensive Cancer Center Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
- Department of Translational Medicine, Lund University, Lund, Sweden.
| |
Collapse
|
4
|
Shaopeng Z, Yang Z, Yuan F, Chen H, Zhengjun Q. Regulation of regulatory T cells and tumor-associated macrophages in gastric cancer tumor microenvironment. Cancer Med 2024; 13:e6959. [PMID: 38349050 PMCID: PMC10839124 DOI: 10.1002/cam4.6959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 01/10/2024] [Accepted: 01/14/2024] [Indexed: 02/15/2024] Open
Abstract
INTRODUCTION Despite advancements in the methods for prevention and early diagnosis of gastric cancer (GC), GC continues to be the fifth in incidence among major cancers and the third most common cause of cancer-related death. The therapeutic effects of surgery and drug treatment are still unsatisfied and show notable differences according to the tumor microenvironment (TME) of GC. METHODS Through screening Pubmed, Embase, and Web of Science, we identified and summarized the content of recent studies that focus on the investigation of Helicobacter pylori (Hp) infection, regulatory T cells (Tregs), and tumor-associated macrophages (TAMs) in the TME of GC. Furthermore, we searched and outlined the clinical research progress of various targeted drugs in GC treatment including CTLA-4, PD-1\PD-L1, and VEGF/VEGFR. RESULTS In this review, the findings indicate that Hp infection causes local inflammation and leads to immunosuppressive environment. High Tregs infiltration in the TME of GC is associated with increased induction and recruitment; the exact function of infiltrated Tregs in GC was also affected by phenotypes and immunosuppressive molecules. TAMs promote the development and metastasis of tumors, the induction, recruitment, and function of TAMs in the TME of gastric cancer are also regulated by various factors. CONCLUSION Discussing the distinct tumor immune microenvironment (TIME) of GC can deepen our understanding on the mechanism of cancer immune evasion, invasion, and metastasis, help us to reduce the incidence of GC, and guide the innovation of new therapeutic targets for GC eventually.
Collapse
Affiliation(s)
- Zhang Shaopeng
- Department of Gastrointestinal Surgery, Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghaiChina
| | - Zheng Yang
- Department of Gastrointestinal Surgery, Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghaiChina
| | - Fang Yuan
- Department of Gastrointestinal Surgery, Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghaiChina
| | - Huang Chen
- Department of Gastrointestinal Surgery, Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghaiChina
| | - Qiu Zhengjun
- Department of Gastrointestinal Surgery, Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghaiChina
| |
Collapse
|
5
|
Sathe A, Ayala C, Bai X, Grimes SM, Lee B, Kin C, Shelton A, Poultsides G, Ji HP. GITR and TIGIT immunotherapy provokes divergent multicellular responses in the tumor microenvironment of gastrointestinal cancers. Genome Med 2023; 15:100. [PMID: 38008725 PMCID: PMC10680277 DOI: 10.1186/s13073-023-01259-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 11/14/2023] [Indexed: 11/28/2023] Open
Abstract
BACKGROUND Understanding the mechanistic effects of novel immunotherapy agents is critical to improving their successful clinical translation. These effects need to be studied in preclinical models that maintain the heterogenous tumor microenvironment (TME) and dysfunctional cell states found in a patient's tumor. We investigated immunotherapy perturbations targeting co-stimulatory molecule GITR and co-inhibitory immune checkpoint TIGIT in a patient-derived ex vivo system that maintains the TME in its near-native state. Leveraging single-cell genomics, we identified cell type-specific transcriptional reprogramming in response to immunotherapy perturbations. METHODS We generated ex vivo tumor slice cultures from fresh surgical resections of gastric and colon cancer and treated them with GITR agonist or TIGIT antagonist antibodies. We applied paired single-cell RNA and TCR sequencing to the original surgical resections, control, and treated ex vivo tumor slice cultures. We additionally confirmed target expression using multiplex immunofluorescence and validated our findings with RNA in situ hybridization. RESULTS We confirmed that tumor slice cultures maintained the cell types, transcriptional cell states and proportions of the original surgical resection. The GITR agonist was limited to increasing effector gene expression only in cytotoxic CD8 T cells. Dysfunctional exhausted CD8 T cells did not respond to GITR agonist. In contrast, the TIGIT antagonist increased TCR signaling and activated both cytotoxic and dysfunctional CD8 T cells. This included cells corresponding to TCR clonotypes with features indicative of potential tumor antigen reactivity. The TIGIT antagonist also activated T follicular helper-like cells and dendritic cells, and reduced markers of immunosuppression in regulatory T cells. CONCLUSIONS We identified novel cellular mechanisms of action of GITR and TIGIT immunotherapy in the patients' TME. Unlike the GITR agonist that generated a limited transcriptional response, TIGIT antagonist orchestrated a multicellular response involving CD8 T cells, T follicular helper-like cells, dendritic cells, and regulatory T cells. Our experimental strategy combining single-cell genomics with preclinical models can successfully identify mechanisms of action of novel immunotherapy agents. Understanding the cellular and transcriptional mechanisms of response or resistance will aid in prioritization of targets and their clinical translation.
Collapse
Affiliation(s)
- Anuja Sathe
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, CCSR 2245, 269 Campus Drive, Stanford, CA, 94305, USA
| | - Carlos Ayala
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, USA
| | - Xiangqi Bai
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, CCSR 2245, 269 Campus Drive, Stanford, CA, 94305, USA
| | - Susan M Grimes
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, CCSR 2245, 269 Campus Drive, Stanford, CA, 94305, USA
| | - Byrne Lee
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, USA
| | - Cindy Kin
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, USA
| | - Andrew Shelton
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, USA
| | - George Poultsides
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, USA
| | - Hanlee P Ji
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, CCSR 2245, 269 Campus Drive, Stanford, CA, 94305, USA.
| |
Collapse
|
6
|
Borgeaud M, Sandoval J, Obeid M, Banna G, Michielin O, Addeo A, Friedlaender A. Novel targets for immune-checkpoint inhibition in cancer. Cancer Treat Rev 2023; 120:102614. [PMID: 37603905 DOI: 10.1016/j.ctrv.2023.102614] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/06/2023] [Accepted: 08/09/2023] [Indexed: 08/23/2023]
Abstract
Immune-checkpoint inhibitors have revolutionized cancer therapy, yet many patients either do not derive any benefit from treatment or develop a resistance to checkpoint inhibitors. Intrinsic resistance can result from neoantigen depletion, defective antigen presentation, PD-L1 downregulation, immune-checkpoint ligand upregulation, immunosuppression, and tumor cell phenotypic changes. On the other hand, extrinsic resistance involves acquired upregulation of inhibitory immune-checkpoints, leading to T-cell exhaustion. Current data suggest that PD-1, CTLA-4, and LAG-3 upregulation limits the efficacy of single-agent immune-checkpoint inhibitors. Ongoing clinical trials are investigating novel immune-checkpoint targets to avoid or overcome resistance. This review provides an in-depth analysis of the evolving landscape of potentially targetable immune-checkpoints in cancer. We highlight their biology, emphasizing the current understanding of resistance mechanisms and focusing on promising strategies that are under investigation. We also summarize current results and ongoing clinical trials in this crucial field that could once again revolutionize outcomes for cancer patients.
Collapse
Affiliation(s)
| | | | - Michel Obeid
- Centre Hospitalier Universitaire Vaudois, Switzerland
| | - Giuseppe Banna
- Portsmouth Hospitals University NHS Trust, Portsmouth, UK
| | | | | | - Alex Friedlaender
- Geneva University Hospitals, Switzerland; Clinique Générale Beaulieu, Geneva, Switzerland.
| |
Collapse
|
7
|
Sathe A, Ayala C, Bai X, Grimes SM, Lee B, Kin C, Shelton A, Poultsides G, Ji HP. GITR and TIGIT immunotherapy provokes divergent multi-cellular responses in the tumor microenvironment of gastrointestinal cancers. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.13.532299. [PMID: 36993756 PMCID: PMC10054933 DOI: 10.1101/2023.03.13.532299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Understanding the cellular mechanisms of novel immunotherapy agents in the human tumor microenvironment (TME) is critical to their clinical success. We examined GITR and TIGIT immunotherapy in gastric and colon cancer patients using ex vivo slice tumor slice cultures derived from cancer surgical resections. This primary culture system maintains the original TME in a near-native state. We applied paired single-cell RNA and TCR sequencing to identify cell type specific transcriptional reprogramming. The GITR agonist was limited to increasing effector gene expression only in cytotoxic CD8 T cells. The TIGIT antagonist increased TCR signaling and activated both cytotoxic and dysfunctional CD8 T cells, including clonotypes indicative of potential tumor antigen reactivity. The TIGIT antagonist also activated T follicular helper-like cells and dendritic cells, and reduced markers of immunosuppression in regulatory T cells. Overall, we identified cellular mechanisms of action of these two immunotherapy targets in the patients' TME.
Collapse
Affiliation(s)
- Anuja Sathe
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States
| | - Carlos Ayala
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, United States
| | - Xiangqi Bai
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States
| | - Susan M. Grimes
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States
| | - Byrne Lee
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, United States
| | - Cindy Kin
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, United States
| | - Andrew Shelton
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, United States
| | - George Poultsides
- Division of Surgical Oncology, Department of Surgery, Stanford University, Stanford, CA, United States
| | - Hanlee P. Ji
- Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States
| |
Collapse
|
8
|
Iglesias-Escudero M, Arias-González N, Martínez-Cáceres E. Regulatory cells and the effect of cancer immunotherapy. Mol Cancer 2023; 22:26. [PMID: 36739406 PMCID: PMC9898962 DOI: 10.1186/s12943-023-01714-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 01/02/2023] [Indexed: 02/06/2023] Open
Abstract
Several mechanisms and cell types are involved in the regulation of the immune response. These include mostly regulatory T cells (Tregs), regulatory macrophages (Mregs), myeloid suppressor cells (MDSCs) and other regulatory cell types such as tolerogenic dendritic cells (tolDCs), regulatory B cells (Bregs), and mesenchymal stem cells (MSCs). These regulatory cells, known for their ability to suppress immune responses, can also suppress the anti-tumor immune response. The infiltration of many regulatory cells into tumor tissues is therefore associated with a poor prognosis. There is growing evidence that elimination of Tregs enhances anti-tumor immune responses. However, the systemic depletion of Treg cells can simultaneously cause deleterious autoimmunity. Furthermore, since regulatory cells are characterized by their high level of expression of immune checkpoints, it is also expected that immune checkpoint inhibitors perform part of their function by blocking these molecules and enhancing the immune response. This indicates that immunotherapy does not only act by activating specific effector T cells but can also directly or indirectly attenuate the suppressive activity of regulatory cells in tumor tissues. This review aims to draw together our current knowledge about the effect of immunotherapy on the various types of regulatory cells, and how these effects may be beneficial in the response to immunotherapy.
Collapse
Affiliation(s)
- María Iglesias-Escudero
- Immunology Division, LCMN, Germans Trias i Pujol University Hospital and Research Institute, Campus Can Ruti, Badalona, Spain. .,Department of Cellular Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain.
| | - Noelia Arias-González
- grid.411438.b0000 0004 1767 6330Immunology Division, LCMN, Germans Trias i Pujol University Hospital and Research Institute, Campus Can Ruti, Badalona, Spain
| | - Eva Martínez-Cáceres
- Immunology Division, LCMN, Germans Trias i Pujol University Hospital and Research Institute, Campus Can Ruti, Badalona, Spain. .,Department of Cellular Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain.
| |
Collapse
|