title: RelA-Mediated BECN1 Expression Is Required for Reactive Oxygen Species-Induced Autophagy in Oral Cancer Cells Exposed to Low-Power Laser Irradiation.
abstract: Low-power laser irradiation (LPLI) is a non-invasive and safe method for cancer treatment that alters a variety of physiological processes in the cells. Autophagy can play either a cytoprotective role or a detrimental role in cancer cells exposed to stress. The detailed mechanisms of autophagy and its role on cytotoxicity in oral cancer cells exposed to LPLI remain unclear. In this study, we showed that LPLI at 810 nm with energy density 60 J/cm2 increased the number of microtubule associated protein 1 light chain 3 (MAP1LC3) puncta and increased autophagic flux in oral cancer cells. Moreover, reactive oxygen species (ROS) production was induced, which increased RelA transcriptional activity and beclin 1 (BECN1) expression in oral cancer cells irradiated with LPLI. Furthermore, ROS scavenger or knockdown of RelA diminished LPLI-induced BECN1 expression and MAP1LC3-II conversion. In addition, pharmacological and genetic ablation of autophagy significantly enhanced the effects of LPLI-induced apoptosis in oral cancer cells. These results suggest that autophagy may be a resistant mechanism for LPLI-induced apoptosis in oral cancer cells.
authors.affiliation: Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Chih-Wen
authors.initials: CW
authors.lastname: Shu
authors.affiliation: Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Hong-Tai
authors.initials: HT
authors.lastname: Chang
authors.affiliation: Department of Dermatology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Chieh-Shan
authors.initials: CS
authors.lastname: Wu
authors.affiliation: Radiation Oncology Department, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Chien-Hsun
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Samwell Testing INC, Taipei, Taiwan.
authors.forename: Sam
authors.initials: S
authors.lastname: Wu
authors.affiliation: Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan.|Research Center of Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Hsueh-Wei
authors.initials: HW
authors.lastname: Chang
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, School of Medical and Health Sciences, Fooyin University, Kaohsiung, Taiwan.
authors.forename: Soong-Yu
authors.initials: SY
authors.lastname: Kuo
authors.affiliation: Department of Periodontology, School of Dentistry, National Defense Medical Center and Tri-Service General Hospital, Taipei, Taiwan.
authors.forename: Earl
authors.initials: E
authors.lastname: Fu
authors.affiliation: Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.|Department of Biotechnology, Fooyin University, Kaohsiung, Taiwan.
authors.forename: Pei-Feng
authors.initials: PF
authors.lastname: Liu
authors.affiliation: Department of Stomatology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Yao-Dung
authors.initials: YD
authors.lastname: Hsieh
mesh_terms: D001343:Autophagy; D000071186:Beclin-1 / Q000378:metabolism*; D006801:Humans; D028022:Low-Level Light Therapy; D009062:Mouth Neoplasms / Q000276:immunology / Q000473:pathology*; D016328:NF-kappa B / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D051996:Transcription Factor RelA / Q000378:metabolism*
chemical_list: C491997:BECN1 protein, human; D000071186:Beclin-1; D016328:NF-kappa B; C498143:RELA protein, human; D017382:Reactive Oxygen Species; D051996:Transcription Factor RelA