title: Effects of X-radiation on lung cancer cells: the interplay between oxidative stress and P53 levels.
abstract: Lung cancer (LC) ranks as the most prevalent and deadliest cause of cancer death worldwide. Treatment options include surgery, chemotherapy and/or radiotherapy, depending on LC staging, without specific highlight. The aim was to evaluate the effects of X-radiation in three LC cell lines. H69, A549 and H1299 cell lines were cultured and irradiated with 0.5-60 Gy of X-radiation. Cell survival was evaluated by clonogenic assay. Cell death and the role of reactive oxygen species, mitochondrial membrane potential, BAX, BCL-2 and cell cycle were analyzed by flow cytometry. Total and phosphorylated P53 were assessed by western blotting. Ionizing radiation decreases cell proliferation and viability in a dose-, time- and cell line-dependent manner, inducing cell death preferentially by apoptosis with cell cycle arrest. These results may be related to differences in P53 expression and oxidative stress response. The results obtained indicate that sensibility and/or resistance to radiation may be dependent on molecular LC characteristics which could influence response to radiotherapy and treatment success.
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal. fjmendes@estescoimbra.pt.|Department Biomedical Laboratory Sciences, ESTESC-Coimbra Health School, Polytechnic Institute of Coimbra, Coimbra, Portugal. fjmendes@estescoimbra.pt.|Faculty of Medicine, Center of Investigation in Environment, Genetics and Oncobiology (CIMAGO), University of Coimbra, Coimbra, Portugal. fjmendes@estescoimbra.pt.
authors.forename: Fernando
authors.initials: F
authors.lastname: Mendes
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.
authors.forename: Tiago
authors.initials: T
authors.lastname: Sales
authors.affiliation: Faculty of Medicine, Center of Investigation in Environment, Genetics and Oncobiology (CIMAGO), University of Coimbra, Coimbra, Portugal.|Faculty of Medicine, Applied Molecular Biology and Clinical University of Hematology, University of Coimbra, Coimbra, Portugal.
authors.forename: Cátia
authors.initials: C
authors.lastname: Domingues
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.
authors.forename: Susann
authors.initials: S
authors.lastname: Schugk
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.|Faculty of Medicine, Center of Investigation in Environment, Genetics and Oncobiology (CIMAGO), University of Coimbra, Coimbra, Portugal.
authors.forename: Ana Margarida
authors.initials: AM
authors.lastname: Abrantes
authors.affiliation: Faculty of Medicine, Center of Investigation in Environment, Genetics and Oncobiology (CIMAGO), University of Coimbra, Coimbra, Portugal.|Faculty of Medicine, Applied Molecular Biology and Clinical University of Hematology, University of Coimbra, Coimbra, Portugal.
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Gonçalves
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Teixo
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.
authors.forename: Rita
authors.initials: R
authors.lastname: Silva
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.|Radiation Oncology Department, Hospital and University Center of Coimbra, Coimbra, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Casalta-Lopes
authors.affiliation: Department Complementary Sciences, ESTESC-Coimbra Health School, Polytechnic Institute of Coimbra, Coimbra, Portugal.|Institute for Systems Engineering and Computers at Coimbra, Coimbra, Portugal.
authors.forename: Clara
authors.initials: C
authors.lastname: Rocha
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.
authors.forename: Mafalda
authors.initials: M
authors.lastname: Laranjo
authors.affiliation: Radiation Oncology Department, Hospital and University Center of Coimbra, Coimbra, Portugal.
authors.forename: Paulo César
authors.initials: PC
authors.lastname: Simões
authors.affiliation: Faculty of Medicine, Center of Investigation in Environment, Genetics and Oncobiology (CIMAGO), University of Coimbra, Coimbra, Portugal.|Faculty of Medicine, Applied Molecular Biology and Clinical University of Hematology, University of Coimbra, Coimbra, Portugal.|Cento Hospitalar Universitário de Coimbra, Coimbra, Portugal.|CNC.IBILI, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Ana Bela Sarmento
authors.initials: AB
authors.lastname: Ribeiro
authors.affiliation: Biophysics Unit-CNC.IBILI, Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548, Coimbra, Portugal.|Faculty of Medicine, Center of Investigation in Environment, Genetics and Oncobiology (CIMAGO), University of Coimbra, Coimbra, Portugal.
authors.forename: Maria Filomena
authors.initials: MF
authors.lastname: Botelho
authors.affiliation: Faculty of Medicine, Immunology Institute, University of Coimbra, Coimbra, Portugal.
authors.forename: Manuel Santos
authors.initials: MS
authors.lastname: Rosa
mesh_terms: D017209:Apoptosis / Q000528:radiation effects; D045744:Cell Line, Tumor; D006801:Humans; D008175:Lung Neoplasms / Q000532:radiotherapy*; D008954:Models, Biological; D018384:Oxidative Stress / Q000528:radiation effects*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000378:metabolism*; D014965:X-Rays
chemical_list: D016159:Tumor Suppressor Protein p53
keywords: Lung cancer; Oxidative stress; P53; Radiotherapy