title: Differences in Redox Regulatory Systems in Human Lung and Liver Tumors Suggest Different Avenues for Therapy.
abstract: A common characteristic of many cancer cells is that they suffer from oxidative stress. They, therefore, require effective redox regulatory systems to combat the higher levels of reactive oxygen species that accompany accelerated growth compared to the normal cells of origin. An elevated dependence on these systems in cancers suggests that targeting these systems may provide an avenue for retarding the malignancy process. Herein, we examined the redox regulatory systems in human liver and lung cancers by comparing human lung adenocarcinoma and liver carcinoma to their respective surrounding normal tissues. Significant differences were found in the two major redox systems, the thioredoxin and glutathione systems. Thioredoxin reductase 1 levels were elevated in both malignancies, but thioredoxin was highly upregulated in lung tumor and only slightly upregulated in liver tumor, while peroxiredoxin 1 was highly elevated in lung tumor, but downregulated in liver tumor. There were also major differences within the glutathione system between the malignancies and their normal tissues. The data suggest a greater dependence of liver on either the thioredoxin or glutathione system to drive the malignancy, while lung cancer appeared to depend primarily on the thioredoxin system.
authors.affiliation: Molecular Biology of Selenium Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. tober@fc.ritsumei.ac.jp.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Tobe
authors.affiliation: Molecular Biology of Selenium Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. carlsonb@mail.nih.gov.
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Carlson
authors.affiliation: Department of Biological Sciences, Towson University, Towson, MD 21252, USA. ptsuji@towson.edu.
authors.forename: Petra A
authors.initials: PA
authors.lastname: Tsuji
authors.affiliation: School of Biological Sciences, Seoul National University, Seoul 151-742, Korea. imbglmg@snu.ac.kr.
authors.forename: Byeong Jae
authors.initials: BJ
authors.lastname: Lee
authors.affiliation: Department of Medicine, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115,USA. vgladyshev@rics.bwh.harvard.edu.
authors.forename: Vadim N
authors.initials: VN
authors.lastname: Gladyshev
authors.affiliation: Molecular Biology of Selenium Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. hatfield@mail.nih.gov.
authors.forename: Dolph L
authors.initials: DL
authors.lastname: Hatfield
keywords: antioxidant systems; glutathione; glutathione peroxidase; thioredoxin 1; thioredoxin reductase 1