title: The role of selective COX-2 inhibitors in reactive oxygen species formation in osteosarcoma cells after X-ray irradiation.
abstract: Selective inhibition of COX-2 is thought to prevent carcinogenesis in some malignant tumors. In this study, in an effort to enhance the effectiveness of osteosarcoma treatment, we investigated the effect of a selective inhibitor of COX-2, with or without irradiation. We also asked whether selective COX-2 inhibitors increase the effect of X-ray irradiation, with regard to reactive oxygen species (ROS) formation in an osteosarcoma cell line. Our results showed that the presence of COX-2 inhibitor without irradiation results in faint spots of ROS formation that do not appear in the absence of COX-2 inhibitor. However, COX-2 inhibitor did not induce ROS formation when combined with irradiation. Thus, radiotherapy with selective COX-2 inhibitions has limitations in the treatment of radioresistant osteosarcoma to obtain the effective achievement, it is indispensable to combine another agent in future studies.
authors.affiliation: Department of Orthopaedics, Medical School, Kochi University, Oko-cho, Nankoku, Kochi 783-8505, Japan. takahast@med.kochi-u.ac.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Takahashi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sonobe
authors.forename: Harumichi
authors.initials: H
authors.lastname: Seguchi
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Tani
authors.forename: Shoji
authors.initials: S
authors.lastname: Yoshida
mesh_terms: D045744:Cell Line, Tumor; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D008856:Microscopy, Fluorescence; D012516:Osteosarcoma / Q000188:drug therapy / Q000378:metabolism* / Q000532:radiotherapy; D017382:Reactive Oxygen Species / Q000378:metabolism* / Q000528:radiation effects*; D014965:X-Rays
chemical_list: D016861:Cyclooxygenase Inhibitors; D017382:Reactive Oxygen Species