title: Expression of Antioxidant Molecules and Heat Shock Protein 27 in Thyroid Tumors.
abstract: Oxidative stress-induced DNA damage is a known causing factor for many types of tumors, but information on the role of oxidants and antioxidants in thyroid tumors is limited. The aim of this study was to determine antioxidant levels in thyroid tumors. In this study, tumor and its matched non-tumor thyroid tissue samples were obtained from 53 patients with thyroid tumors. The levels of manganese superoxide dismutase (MnSOD), thioredoxin reductase 2 (TXNRD2), glutathione (GSH), glutathione peroxidase (Gpx), catalase (CAT), and 27 kd heat-shock protein (hsp27) were determined in both thyroid tissue samples and cultured thyroid cells by immunohistochemical staining and western blot. Hydrogen peroxide (H2 O2 ) was used to generate oxidant stress in the cell culture experiments. We found that the levels of MnSOD, TXNRD2, GSH, Gpx, and Hsp27 were increased in both malignant and benign tumors, while the level of CAT was decreased. To verify the results of the tissue study, we treated cultured thyroid cells with H2 O2 and found the same pattern of antioxidant changes. Hsp27 was also increased after H2 O2 treatment. The expression of hsp27 was upregulated by 8.24-, 6.96-, and 3.09-fold in thyroid cancer, follicular adenoma, multinodular goiter, respectively. Collectively, our study demonstrated that the levels of hsp27 together with MnSOD, TXNRD2, GSH, and Gpx were significantly upregulated by H2 O2 in thyroid tumors. The increase of these antioxidants is observed in both malignant and benign tumors, particularly in the former. The upregulation of antioxidants is likely a protective mechanism of tumor cells to maintain their survival and growth. J. Cell. Biochem. 117: 2473-2481, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Shucui
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Vlantis
authors.affiliation: Department of Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Shirley Y W
authors.initials: SY
authors.lastname: Liu
authors.affiliation: Department of Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Enders K W
authors.initials: EK
authors.lastname: Ng
authors.affiliation: Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, NT, Hong Kong, China.
authors.forename: Amy B W
authors.initials: AB
authors.lastname: Chan
authors.affiliation: Department of Thyroid and Breast Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong 510665, China.
authors.forename: Juekun
authors.initials: J
authors.lastname: Wu
authors.affiliation: Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Du
authors.affiliation: Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.affiliation: Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, China.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Liu
authors.affiliation: Faculty of Basic Medical Sciences, Department of Biochemistry and Molecular Biology, Chongqing Medical University, Chongqing 40016, China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Siu Kwan
authors.initials: SK
authors.lastname: Ng
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: C Andrew
authors.initials: CA
authors.lastname: van Hasselt
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.
authors.forename: Michael C F
authors.initials: MC
authors.lastname: Tong
authors.affiliation: Department of Surgery, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China. gchen@cuhk.edu.hk.
authors.forename: George G
authors.initials: GG
authors.lastname: Chen
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000378:metabolism* / Q000473:pathology; D000975:Antioxidants / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002291:Carcinoma, Papillary / Q000378:metabolism* / Q000473:pathology; D002478:Cells, Cultured; D015972:Gene Expression Regulation, Neoplastic; D055551:HSP27 Heat-Shock Proteins / Q000378:metabolism*; D006360:Heat-Shock Proteins; D006801:Humans; D007124:Immunoenzyme Techniques; D018832:Molecular Chaperones; D018384:Oxidative Stress; D013961:Thyroid Gland / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D000975:Antioxidants; D014408:Biomarkers, Tumor; D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones
keywords: 27 kd HEAT-SHOCK PROTEIN; ANTIOXIDANTS; OXIDANTS; THYROID TUMORS