17-AAG, an inhibitor of heat shock protein 90, down-regulates hepatitis B virus replication
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摘要: 目的探讨热休克蛋白90(HSP90)是否参与肝细胞转化生长因子(TGF)β信号通路的活化,以及HSP90对乙型肝炎病毒(HBV)复制的影响。方法 HSP90抑制剂17-AAG作用HepG2细胞,提取细胞总RNA,实时定量RT-PCR检测TGFβ下游信号分子PAI-1的表达。HepG2细胞用17-AAG预处理2 h,同时用TGFβ或TβR抑制剂SB431542作用后,将HBV复制型质粒HBV1.3转染细胞,第4 d提取HBV核心颗粒,Southern Blot检测HBV复制中间体,ELISA检测上清HBsAg的表达。结果 17-AAG能够下调HepG2细胞PAI-1的表达,HepG2细胞内HBV复制中间体表达水平明显降低,HBsAg的表达亦受到抑制,但上调或阻断TGFβ信号通路对HBV复制影响不明显。结论 HSP90参与肝细胞内TGFβ信号通路的活化,其抑制剂17-AAG能够抑制HBV的复制与蛋白表达,但该抑制作用与TGFβ信号通路活化无关。
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关键词:
- HSP90热休克蛋白类 /
- 肝炎病毒,乙型 /
- 转化生长因子β
Abstract: Objective To investigate the potential involvement of the heat shock protein 90 (HSP90) in transforming growth factor-beta (TGFβ) signaling activation in hepatocytes, and to observe the effect of the HSP90 inhibitor, 17-AAG, on hepatitis B virus (HBV) replication.Methods HepG2 cells were treated with 17-AAG and total RNA was extracted to measure PAI-1 (SERPINE1) expression by real-time RT-PCR.Meanwhile, HepG2 cells were also transfected with the HBV1.3 HBV replicative plasmid after two hours of pretreatment with 17-AAG and TGFβ or SB431542.At day 4 post-transfection, HBV core particles were extracted and HBV replicative intermediates were detected by Southern blotting analysis.HBV surface antigen (HBsAg) was measured by ELISA.Results 17-AAG down-regulated mRNA expression of PAI-1 in HepG2 cells.HBV replication and HBsAg expression were inhibited upon 17-AAG treatment.However, activation of the TGFβ signaling pathway had no effect on HBV replication.Conclusion HSP90 is involved in the TGFβ signaling pathway during HBV infection.The HSP90 inhibitor, 17-AAG, can inhibit HBV replication and HBsAg expression through a TGFβ-independent signaling mechanism. -
[1] Whitesell L, Lindquist SL. HSP90 and the chaperoning of cancer[J]. Nat Rev Cancer, 2005, 5 (10) : 761-772. [2] Blobe GC, Schiemann WP, Lodish HF. Role of transforming growth factor beta in human disease[J]. N Engl J Med, 2000, 342 (18) : 1350-1358. [3]Wrighton KH, Lin X, Feng XH.Critical regulation of TGFbeta sig-naling by Hsp90[J].Proc Natl Acad Sci U S A, 2008, 105 (27) :9244-9249. [4]Hu J, Toft DO, Seeger C.Hepadnavirus assembly and reverse tran-scription require a multi-component chaperone complex which isincorporated into nucleocapsids[J].EMBO J, 1997, 16 (1) :59-68. [5] Hu J, Toft D, Anselmo D, et al. In vitro reconstitution of functional hepadnavirus reverse transcriptase with cellular chaperone proteins[J]. J Virol, 2002, 76 (1) : 269-279. [6]Meng ZJ, Xu Y, Wu J, et al.Inhibition of hepatitis B virus gene ex-pression and replication by endoribonuclease-prepared siRNA[J].JVirol Methods, 2008, 150 (1-2) :27-33. [7] Breitkopf K, Godoy P, Ciuclan L, et al. TGF-beta/Smad signaling in the injured liver[J]. Z Gastroenterol, 2006, 44: 57-66. [8]Pan JB, Clayton M, Feitelson MA.Hepatitis B virus X antigen pro-motes transforming growth factor-b1 (TGF-b1) activity by up-reg-ulation of TGF-b1 and down-regulation of a2-macroglobulin[J].JGen Virol, 2004, 85 (Pt2) :275-282. [9]Dug KL, Seok HP, Youngsuk Y, et al.The hepatitis B virus enco-ded oncoprotein pX amplifies TGFβfamily signaling through directinteraction with Smad4:potential mechanism of hepatitis B virus-induced liver fibrosis[J].Genes Dev, 2001, 15 (4) :455-466. [10]Kakumu S, Ito Y, Wakita T, et al.Effects of transforming growthfactor-beta 1 against the inhibitory action of interferon on DNA syn-thesis and viral replication in hepatitis B virus DNA-transfected cell[J].J Med Virol, 1992, 38 (1) :62-66. [11]Chang CJ, Liao CH, Wang FH.Transforming growth factor-betainduces apoptosis in antigen-specific CD4+T cells prepared for a-doptive immunotherapy[J].Immunol Lett, 2003, 86 (1) :37-43. [12] Hu JM, Flores D, Toft D, et al. Requirement of heat shock protein 90 for human hepatitis B virus reverse transcriptase function[J]. J Virol, 2004, 78 (23) : 13122-13131.
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