title: Dual-specificity phosphatase DUSP1 protects overactivation of hypoxia-inducible factor 1 through inactivating ERK MAPK.
abstract: Hypoxia-inducible factor 1 (HIF-1) plays a critical role in controlling oxygen delivery and metabolic adaptation to hypoxic conditions in hypoxic tumor cells. HIF-1 activation is initiated by several factors including mitogen-activated protein kinase (MAPK) superfamily. We have previously reported that mitogen-activated protein kinase phosphatase DUSP1 (MKP-1) was implicated in the negative regulation of HIF-1alpha subunit phosphorylation and HIF-1 activity. However, the molecular basis by which MKP-1 influences HIF-1 activity is not clarified. In this paper, we show that hypoxia transcriptionally induces MKP-1 expression in a time-dependent manner. Meanwhile, hypoxia also activates extracellular signal-regulated kinase (ERK) whose activity is enhanced or reduced by MKP-1 suppression or MKP-1 overexpression, respectively. We also show that suppression of MKP-1 expression facilitates the interaction between HIF-1alpha subunit and p300, a co-activator of HIF-1. Moreover, MKP-1 suppression leads to enhanced HIF-1 activity, which can be counteracted by PD98059, an ERK kinase inhibitor. Taken together, the results presented here suggest that hypoxia-induced MKP-1 protects overactivation of HIF-1 activation through inhibiting ERK kinase activity.
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, the Fourth Military Medical University, Xi'an 710032, Shaanxi, China.
authors.forename: Changjiang
authors.initials: C
authors.lastname: Liu
authors.forename: Yongquan
authors.initials: Y
authors.lastname: Shi
authors.forename: Yulei
authors.initials: Y
authors.lastname: Du
authors.forename: Xiaoxuan
authors.initials: X
authors.lastname: Ning
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.forename: Dawei
authors.initials: D
authors.lastname: Huang
authors.forename: Jie
authors.initials: J
authors.lastname: Liang
authors.forename: Yan
authors.initials: Y
authors.lastname: Xue
authors.forename: Daiming
authors.initials: D
authors.lastname: Fan
mesh_terms: D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D045744:Cell Line, Tumor; D054638:Dual Specificity Phosphatase 1; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D000860:Hypoxia / Q000378:metabolism*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D017874:Immediate-Early Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D048031:JNK Mitogen-Activated Protein Kinases / Q000096:biosynthesis / Q000235:genetics; D009687:Nuclear Proteins / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D010766:Phosphorylation; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D018797:Cell Cycle Proteins; D005419:Flavonoids; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D017874:Immediate-Early Proteins; D009687:Nuclear Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; C517019:DUSP1 protein, human; D054638:Dual Specificity Phosphatase 1; D017027:Protein Tyrosine Phosphatases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one