title: USP9X destabilizes pVHL and promotes cell proliferation.
abstract: Numerous mutations of the Von Hippel-Lindau (VHL) gene have been reported to cause dysfunction of VHL protein (pVHL) and lead to processes related to tumor progression. pVHL acts as an E3 ligase and degrades downstream targets, such as hypoxia-inducible transcription factor (HIF) which is essential for tumor growth. Previous studies reported reduction of VHL protein, rather than mRNA in VHL-related tumor patients, suggesting that instability of the pVHL protein itself is a primary cause of dysfunction. Regulation of pVHL stability has therefore been a major focus of research. We report that ubiquitin-specific protease 9X (USP9X), which is a deubiquitinase binds and promotes degradation of both wild-type and mutants of pVHL that retain E3 ligase function, thus activating the HIF pathway. USP9X degrades pVHL through protection of its substrate, the newly identified pVHL E3 ligase Smurf1. In addition, USP9X activates glycolysis and promotes cell proliferation through pVHL. Treatment with a USP9X inhibitor shows an effect similar to USP9X knockdown in pVHL induction, and suppresses HIF activity. Our findings demonstrate that USP9X is a novel regulator of pVHL stability, and USP9X may be a therapeutic target for treatment of VHL-related tumors.
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Cong
authors: C
authors: Zhang
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Zuohan
authors: Z
authors: Peng
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Minglu
authors: M
authors: Zhu
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Penglong
authors: P
authors: Wang
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Xiao
authors: X
authors: Du
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Xiang
authors: X
authors: Li
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Yu
authors: Y
authors: Liu
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Yan
authors: Y
authors: Jin
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Michael A
authors: MA
authors: McNutt
authors: Institute of Systems Biomedicine, State Key Laboratory of Natural and Biomimetic Drugs, Beijing Key Laboratory of Tumor Systems Biology, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Peking-Tsinghua Center for Life Sciences, Beijing, 100191, China.
authors: Yuxin
authors: Y
authors: Yin
mesh_terms: D063646:Carcinogenesis; D049109:Cell Proliferation; D064112:Clustered Regularly Interspaced Short Palindromic Repeats; D006019:Glycolysis; D057809:HEK293 Cells; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D055550:Protein Stability; D059748:Proteolysis; D043222:Ubiquitin Thiolesterase / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D054875:Ubiquitination; D051794:Von Hippel-Lindau Tumor Suppressor Protein / Q000235:genetics / Q000378:metabolism*; D006623:von Hippel-Lindau Disease / Q000235:genetics / Q000378:metabolism*
chemical_list: C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; C506234:USP9X protein, human; C498342:SMURF1 protein, human; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D043222:Ubiquitin Thiolesterase; C497446:VHL protein, human
keywords: USP9X; mutation; pVHL; proliferation; protein stability