The tyrosine kinase inhibitor genistein blocks HIV-1 infection in primary human macrophages

Stantchev, Tzanko S.; Markovic, Ingrid; Telford, William G.; Clouse, Kathleen A.; Broder, Christopher C.

doi:10.1016/j.virusres.2006.09.004

Cited by 52 publications

(53 citation statements)

References 107 publications

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“…Another study reported a block of entry and postentry events with the B oligomer of PTX, which modulates signaling independent of G␣ i . Additional studies reported that the tyrosine kinase inhibitor genistein blocks HIV-1 infection in primary human macrophages and that RhoA and filamin A are required for the actin-dependent clustering of CD4 and coreceptor required for membrane fusion (1,20,31,54). These findings indicate that HIV-1 Env-induced signaling plays a crucial role in Env-mediated membrane fusion.…”

Section: Discussionmentioning

confidence: 90%

Induction of the Gα_qSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

Harmon

Ratner

2008

J Virol

109

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Binding of human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) with the primary receptor CD4 and one of two coreceptors, CXCR4 or CCR5, activates a signaling cascade resulting in Rac-1 GTPase activation and stimulation of actin cytoskeletal reorganizations critical for HIV-1-mediated membrane fusion. The mechanism by which HIV-1 Env induces Rac-1 activation and subsequent actin cytoskeleton rearrangement is unknown. In this study, we show that Env-mediated Rac-1 activation is dependent on the activation of G␣ q and its downstream targets. Fusion and Rac-1 activation are mediated by G␣ q and phospholipase C (PLC), as shown by attenuation of fusion and Rac-1 activation in cells either expressing small interfering RNA (siRNA) targeting G␣ q or treated with the PLC inhibitor U73122. Rac-1 activation and fusion were also blocked by multiple protein kinase C inhibitors, by inhibitors of intracellular Ca 2؉ release, by Pyk2-targeted siRNA, and by the Ras inhibitor S-trans,trans-farnesylthiosalicylic acid (FTS). Fusion was blocked without altering cell viability or cell surface localization of CD4 and CCR5. Similar results were obtained when cell fusion was induced by Env expressed on viral and cellular membranes and when cell lines or primary cells were the target. Treatment with inhibitors and siRNA specific for G␣ i or G␣ s signaling mediators had no effect on Env-mediated Rac-1 activation or cell fusion, indicating that the G␣ q pathway alone is responsible. These results could provide a new focus for therapeutic intervention with drugs targeting host signaling mediators rather than viral molecules, a strategy which is less likely to result in resistance.Entry of human immunodeficiency virus type 1 (HIV-1) is mediated by sequential binding of the trimeric HIV envelope glycoprotein (Env) to CD4 and one of two primary chemokine coreceptors, CXCR4 or CCR5. This binding triggers a series of conformational changes in Env that expose the fusion peptide, which then induces the merger of viral or infected cell membranes with target membranes (14,24,53). The HIV-1 Env interaction with CD4 and a coreceptor also stimulates various intracellular signaling events similar to those initiated by their natural ligands, such as phosphorylation of Pyk2, Ca 2ϩ mobilization, activation of RhoGTPases, and actin cytoskeleton rearrangements (15,20,36,37,48,51,53). Actin cytoskeletal remodeling and RhoGTPases play a central role in regulating fusion of biological membranes (13,22). In the case of HIV-1-induced membrane fusion, activation of the RhoGTPase Rac-1 and subsequent actin cytoskeletal reorganizations are required for efficient virus entry and infection (29, 48). The exact mechanism of Env-induced Rac-1 activation that mediates actin cytoskeletal rearrangements and induces membrane fusion has not been investigated.Binding of both CD4 and the coreceptors elicits signaling pathways that result in Rac-1 activation. However, previous results suggest that Env-induced Rac-1 activation is mediated via the coreceptor rat...

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Section: Discussionmentioning

confidence: 90%

Induction of the Gα_qSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

Harmon

Ratner

2008

J Virol

109

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“…[26][27][28][29][30][31][32][33][34][35] Multiple screens for HIV-1 inhibitors relied on in vitro assays, which used viral proteins or their fragments, or on HIV-1 infections/replication as a readout. In vitro screening has identified competitive inhibitors of assembly of the gp41 HR1-and HR2-derived peptides into the 6HB.…”

Section: Introductionmentioning

confidence: 99%

High-Throughput HIV–Cell Fusion Assay for Discovery of Virus Entry Inhibitors

Marin

Giroud

et al. 2015

ASSAY and Drug Development Technologies

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HIV-1 initiates infection by merging its envelope membrane with the target cell membrane, a process that is mediated by the viral Env glycoprotein following its sequential binding to CD4 and coreceptors, CXCR4 or CCR5. Although HIV-1 fusion has been a target for antiviral therapy, the virus has developed resistance to drugs blocking the CCR5 binding or Env refolding steps of this process. This highlights the need for novel inhibitors. Here, we adapted and optimized an enzymatic HIV-cell fusion assay, which reports the transfer of virus-encapsulated b-lactamase into the cytoplasm, to high-throughput screening (HTS) with a 384-well format. The assay was robustly performed in HTS format and was validated by the pilot screen of a small library of pharmacologically active compounds. Several hits identified by screening included a prominent cluster of purinergic receptor antagonists. Functional studies demonstrated that P2X1 receptor antagonists selectively inhibited HIV-1 fusion without affecting the fusion activity of an unrelated virus that enters cells through an endocytic route. The inhibition of HIV-cell fusion by P2X1 antagonists was not through downmodulation of the cell surface expression of CD4 or coreceptors, thus implicating P2X1 receptor in the HIV-1 fusion step. The ability of these antagonists to inhibit viruses regardless of their coreceptor (CXCR4 or CCR5) preference indicates that fusion is blocked at a late step downstream of coreceptor binding. A future large-scale screening campaign for HIV-1 fusion inhibitors, using the above functional readout, will likely reveal novel classes of inhibitors and suggest potential targets for antiviral therapy.

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“…Host signaling through RTKs and other tyrosine kinases has also been shown to play important roles in virus replication. The tyrosine kinase inhibitor genistein was found to block replication of HIV-1, herpes simplex virus type 1 (HSV-1), and arenavirus (51,53,61), for example, and Src family kinases are known to be important for assembly and maturation of dengue virus and West Nile virus (6,19). The Raf/MEK/ERK (42) and PI3K/Akt (9, 10, 15) pathways downstream of RTKs play important roles in influenza virus replication.…”

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confidence: 99%

Receptor Tyrosine Kinase Inhibitors Block Multiple Steps of Influenza A Virus Replication

Kumar

Liang

Parslow

et al. 2011

J Virol

124

130

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Host signaling pathways play important roles in the replication of influenza virus, but their functional effects remain to be characterized at the molecular level. Here we identify two receptor tyrosine kinase inhibitors (RTKIs) of the tyrphostin class that exhibit robust antiviral activity against influenza A virus replication in cultured cells. One of these (AG879) is a selective inhibitor of the nerve growth factor receptor and human epidermal growth factor receptor 2 (TrkA/HER2) signaling; the other, tyrphostin A9 (A9), inhibits the plateletderived growth factor receptor (PDGFR) pathway. We find that each inhibits at least three postentry steps of the influenza virus life cycle: AG879 and A9 both strongly inhibit the synthesis of all three influenza virus RNA species, block Crm1-dependent nuclear export, and also prevent the release of viral particles through a pathway that is modulated by the lipid biosynthesis enzyme farnesyl diphosphate synthase (FPPS). Tests of short hairpin RNA (shRNA) knockdown and additional small-molecule inhibitors confirmed that interventions targeting TrkA can suppress influenza virus replication. Our study suggests that host cell receptor tyrosine kinase signaling is required for maximal influenza virus RNA synthesis, viral ribonucleoprotein (vRNP) nuclear export, and virus release and that specific RTKIs hold promise as novel anti-influenza virus therapeutics.

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The tyrosine kinase inhibitor genistein blocks HIV-1 infection in primary human macrophages

Cited by 52 publications

References 107 publications

Induction of the Gα_qSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

Induction of the Gα_qSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

High-Throughput HIV–Cell Fusion Assay for Discovery of Virus Entry Inhibitors

Receptor Tyrosine Kinase Inhibitors Block Multiple Steps of Influenza A Virus Replication

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The tyrosine kinase inhibitor genistein blocks HIV-1 infection in primary human macrophages

Cited by 52 publications

References 107 publications

Induction of the GαqSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

Induction of the GαqSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

High-Throughput HIV–Cell Fusion Assay for Discovery of Virus Entry Inhibitors

Receptor Tyrosine Kinase Inhibitors Block Multiple Steps of Influenza A Virus Replication

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Induction of the Gα_qSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry

Induction of the Gα_qSignaling Cascade by the Human Immunodeficiency Virus Envelope Is Required for Virus Entry