Antiviral activity of CYC202 in HIV-1-infected cells.
There are currently 40 million individuals in the world infected with human immunodeficiency virus (HIV). The introduction of highly active antiretroviral therapy (HAART) has led to a significant reduction in AIDS-related morbidity and mortality. Unfortunately, up to 25% of patients discontinue their initial HAART regimen. Current HIV-1 inhibitors target the fusion of the virus to the cell and two viral proteins, reverse transcriptase and protease. Here, we examined whether other targets, such as an activated transcription factor, could be targeted to block HIV-1 replication. We specifically asked whether we could target a cellular kinase needed for HIV-1 transcription using CYC202 (R-roscovitine), a pharmacological cyclin-dependent kinase inhibitor. We targeted the cdk2-cyclin E complex in HIV-1-infected cells because both cdk2 and cyclin E are nonessential during mammalian development and are likely replaced by other kinases. We found that CYC202 effectively inhibits wild type and resistant HIV-1 mutants in T-cells, monocytes, and peripheral blood mononuclear cells at a low IC(50) and sensitizes these cells to enhanced apoptosis resulting in a dramatic drop in viral titers. Interestingly, the effect of CYC202 is independent of cell cycle stage and more specific for the cdk2-cyclin E complex. Finally, we show that cdk2-cyclin E is loaded onto the HIV-1 genome in vivo and that CYC202 is able to inhibit the uploading of this cdk-cyclin complex onto HIV-1 DNA. Therefore, targeting cellular enzymes necessary for HIV-1 transcription, which are not needed for cell survival, is a compelling strategy to inhibit wild type and mutant HIV-1 strains.
Agbottah
Emmanuel
E
Department of Biochemistry and Molecular Biology, The George Washington University, School of Medicine, Washington, DC 20037, USA.
de La Fuente
Cynthia
C
Nekhai
Sergie
S
Barnett
Anna
A
Gianella-Borradori
Athos
A
Pumfery
Anne
A
Kashanchi
Fatah
F
D023241:Antiretroviral Therapy, Highly Active; D000998:Antiviral Agents / Q000494:pharmacology*; D017209:Apoptosis; D042846:CDC2-CDC28 Kinases / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D047369:Chromatin Immunoprecipitation; D019927:Cyclin E / Q000378:metabolism; D051357:Cyclin-Dependent Kinase 2; D053938:DNA Fragmentation; D004279:DNA, Viral; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000378:metabolism; D005434:Flow Cytometry; D016679:Genome, Viral; D015497:HIV-1 / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D020128:Inhibitory Concentration 50; D007963:Leukocytes, Mononuclear / Q000378:metabolism / Q000821:virology; D009000:Monocytes / Q000821:virology; D009154:Mutation; D010766:Phosphorylation; D011687:Purines / Q000494:pharmacology*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D000077546:Roscovitine; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects
D000998:Antiviral Agents; D019927:Cyclin E; D004279:DNA, Viral; D011687:Purines; D034741:RNA, Small Interfering; D013778:Tetrazolium Salts; D013844:Thiazoles; D000077546:Roscovitine; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2; C022616:thiazolyl blue