title: The role of immune system exhaustion on cancer cell escape and anti-tumor immune induction after irradiation.
abstract: Immune surveillance seems to represent an effective tumor suppressor mechanism. However, some cancer cells survive and become variants, being poorly immunogenic and able to enter a steady-state phase. These cells become functionally dormant or remain hidden clinically throughout. Neoplastic cells seem to be able to instruct immune cells to undergo changes promoting malignancy. Radiotherapy may act as a trigger of the immune response. After radiotherapy a sequence of reactions occurs, starting in the damage of oncogenic cells by multiple mechanisms, leading to the immune system positive feedback against the tumor. The link between radiotherapy and the immune system is evident. T cells, macrophages, Natural Killer cells and other immune cells seem to have a key role in controlling the tumor. T cells may be dysfunctional and remain in a state of T cell exhaustion, nonetheless, they often retain a high potential for successful defense against cancer, being able to be mobilized to become highly functional. The lack of clinical trials on a large scale makes data a little robust, in spite of promising information, there are still many variables in the studies relating to radiation and immune system. The clarification of the mechanisms underlying immune response to radiation exposure may contribute to treatment improvement, gain of life quality and span of patients.
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal; Polytechnic Institute of Coimbra, ESTESC-Coimbra Health School, Department Biomedical Laboratory Sciences, Coimbra, Portugal; CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal.
authors: Fernando
authors: F
authors: Mendes
authors: CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; Applied Molecular Biology and Clinical University of Hematology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors: Cátia
authors: C
authors: Domingues
authors: CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; Immunology Institute, Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Hematology Clinic Department, Coimbra Hospital and University Centre, Coimbra, Portugal; Immunology and Oncology Laboratory, Center for Neurosciences and Cell Biology, University of Coimbra, Coimbra, Portugal.
authors: Paulo
authors: P
authors: Rodrigues-Santos
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal; CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal.
authors: Ana Margarida
authors: AM
authors: Abrantes
authors: CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; Applied Molecular Biology and Clinical University of Hematology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors: Ana Cristina
authors: AC
authors: Gonçalves
authors: Polytechnic Institute of Coimbra, ESTESC-Coimbra Health School, Department Biomedical Laboratory Sciences, Coimbra, Portugal.
authors: Jéssica
authors: J
authors: Estrela
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal.
authors: João
authors: J
authors: Encarnação
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal; CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal.
authors: Ana Salomé
authors: AS
authors: Pires
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal; CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; CNC.IBILI, University of Coimbra, Portugal.
authors: Mafalda
authors: M
authors: Laranjo
authors: Immunology Institute, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors: Vera
authors: V
authors: Alves
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal.
authors: Ricardo
authors: R
authors: Teixo
authors: CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal; Applied Molecular Biology and Clinical University of Hematology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Hematology Clinic Department, Coimbra Hospital and University Centre, Coimbra, Portugal.
authors: Ana Bela
authors: AB
authors: Sarmento
authors: Biophysics and Biomathematics Institute, IBILI-Faculty of Medicine, University of Coimbra, Portugal; CIMAGO, FMUC-Faculty of Medicine, University of Coimbra, Portugal.
authors: Maria Filomena
authors: MF
authors: Botelho
authors: Immunology Institute, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors: Manuel Santos
authors: MS
authors: Rosa
mesh_terms: D006801:Humans; D007107:Immune System / Q000502:physiology*; D007108:Immune Tolerance; D009369:Neoplasms / Q000276:immunology / Q000532:radiotherapy*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D019139:Tumor Escape
keywords: Acquire; Cancer; Immune system; Innate; Natural Killer cells; Regulator T cells