title: Suppression of MG132-mediated cell death by peroxiredoxin 1 through influence on ASK1 activation in human thyroid cancer cells.
abstract: Proteasome inhibitors represent a novel class of antitumor agents with pre-clinical and clinical evidence of activity against hematologic malignancies and solid tumors. However, emerging evidence indicates that antiapoptotic factors may also accumulate as a consequence of exposure to these drugs, thus it seems plausible that the activation of survival signaling cascades might compromise their antitumoral effects. Peroxiredoxins (PRDXs) are a family of thiol-containing peroxidases identified primarily by their ability to remove cellular hydroperoxides. The function of PRDX1 in particular has been implicated in regulating cell proliferation, differentiation, and apoptosis. Another important finding is that aberrant upregulation of PRDX1 has been discovered in various cancers. Apoptosis signal-regulating kinase 1 (ASK1) is a mitogen-activated protein kinase (MAPK) kinase kinase that is regulated under conditions of cellular stress. ASK1 phosphorylates c-Jun N-terminal kinase and p38 MAPK, and elicits an apoptotic response. ASK1 activity is regulated at multiple levels, one of which is through interaction with PRDX1. In this study, for the first time we report that upregulation of PRDX1 expression was found in thyroid cancer cells treated with proteasome inhibitors, and PRDX1 knockdown resulted in accelerated proteasome inhibitor-induced cell death. In addition, we demonstrated that ASK1 activity was implicated in the PRDX1-dependent response of thyroid cancer cells to proteasome inhibitor-mediated cell death.
authors.affiliation: Department of Endocrinology and Metabolism, The First Affiliated Hospital, China Medical University, Shenyang 110001, People's Republic of China.
authors.forename: Zhen-Xian
authors.initials: ZX
authors.lastname: Du
authors.forename: Ying
authors.initials: Y
authors.lastname: Yan
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Zhang
authors.forename: Bao-Qin
authors.initials: BQ
authors.lastname: Liu
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Gao
authors.forename: Xiao-Fang
authors.initials: XF
authors.lastname: Niu
authors.forename: Yifu
authors.initials: Y
authors.lastname: Guan
authors.forename: Xin
authors.initials: X
authors.lastname: Meng
authors.forename: Hua-Qin
authors.initials: HQ
authors.lastname: Wang
mesh_terms: D000704:Analysis of Variance; D015153:Blotting, Western; D016923:Cell Death / Q000187:drug effects / Q000502:physiology*; D045744:Cell Line, Tumor; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D006801:Humans; D007976:Leupeptins / Q000494:pharmacology*; D048848:MAP Kinase Kinase Kinase 5 / Q000235:genetics / Q000378:metabolism*; D054464:Peroxiredoxins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013961:Thyroid Gland / Q000378:metabolism*; D014162:Transfection
chemical_list: D015853:Cysteine Proteinase Inhibitors; D007976:Leupeptins; D012333:RNA, Messenger; D054464:Peroxiredoxins; D048848:MAP Kinase Kinase Kinase 5; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde