Project description:Analysis of HeLa cells treated with histone deacetylase inhibitor SAHA for 24hr. Results provide insight into the effect of SAHA on the activation of lysosomal and autophagy pathways
Project description:Suberoylanilide hydroxamic acid (SAHA) has been assessed in clinical trials as part of a “shock and kill” strategy to cure HIV-infected patients. While it was effective at inducing expression of HIV RNA "shock" , treatment with SAHA did not result in the reduction of reservoir size "kill". We therefore utilized a systems biology approach to dissect the mechanisms of action of SAHA that may explain its limited success in “shock and kill” strategies. CD4+ T cells from HIV seronegative donors were treated with 1 uM SAHA or its solvent dimethyl sulfoxide for 24 hours. Differential protein expression and post-translational modification was measured with two-dimensional liquid chromatography - tandem mass spectrometry iTRAQ proteomics. Gene expression changes were assessed by Illumina microarrays. Using limma package in the R computing environment, we identified 185 proteins, 18 phosphorylated forms, 4 acetylated forms and 2,982 genes, whose expression was modulated by SAHA. A protein interaction network integrating these 4 data types identified the transcriptional regulator HMGA1 to be upregulated by SAHA at the transcript, protein and acetylated protein levels. HMGA1 has been shown to repress HIV transcription, which is not optimal with respect to a shock and kill strategy. Further functional category assessment of proteins and genes modulated by SAHA identified gene ontology terms related to NFB signaling, protein folding and autophagy, which are all relevant to HIV reactivation. In summary, this study identified a number of host factors that may be therapeutically targeted to achieve more potent HIV reactivation in the “shock and kill” treatment, when using SAHA, either through modification of SAHA itself or through combination with other latency reversing agents. Finally, proteome profiling highlighted a number of potential adverse effects of SAHA, which transcriptome profiling alone would not have identified.
Project description:The human stool samples were collected and processed for in vitro culturing under anaerobic condition using rapidAIM assay with or without SAHA, an lysine deacetylase inhibitor, for evaluating the effects of SAHA on human gut microbiome. Metaproteomics were used to analyze the microbiome composition and functions.
Project description:Design: Persistent latently infected CD4+ T cells represent a major obstacle to HIV eradication. Histone deacetylase inhibitors (HDACis) are a promising activation therapy in a “shock and kill” strategy. However, off-target effects of HDACis on host gene expression are poorly understood in primary cells of the immune system. We hypothesized that HDACi-modulated genes would be best identified with a dose response analysis. Methods: Resting primary CD4+ T cells were treated with increasing concentrations (0.34, 1, 3, or 10 μM) of the HDACi, suberoylanilide hydroxamic acid (SAHA), for 24 hours and then subjected to microarray gene expression analysis. Genes with dose-correlated expression were identified with a likelihood ratio test using Isogene GX and a subset of these genes with a consistent trend of up or downregulation at each dose of SAHA were identified as dose-responsive. Histone modifications were characterized in promoter regions of the top 6 SAHA dose-responsive genes by RT-qPCR analysis of immunopreciptated chromatin (ChIP). Results: A large number of genes were shown to be up (N=657) or down (N=725) regulated by SAHA in a dose-responsive manner (FDR p-value < 0.05 and fold change ≥ |2|). Several of these genes (CTNNAL1, DPEP2, H1F0, IRGM, PHF15, and SELL) are potential in vivo biomarkers of SAHA activity. SAHA dose-responsive gene categories included transcription factors, HIV restriction factors, histone methyltransferases, and host proteins that interact with HIV proteins or the HIV LTR. Pathway analysis suggested net downregulation of T cell activation with increasing SAHA dose. Histone acetylation was not correlated with host expression, but plausible alternative mechanisms for SAHA-modulated expression were identified. Conclusions: Numerous host genes in CD4+ T cells are modulated by SAHA in a dose-responsive manner, including genes that may negatively influence HIV activation from latency. Our study suggests that SAHA influences gene expression through a confluence of several mechanisms, including histone acetylation, histone methylation, and altered expression and activity of transcription factors.
Project description:We performed a TMT-based quantitative proteomic analysis of SAHA-perturbed human HeLa cells using advanced RTS platform on Orbitrap Eclipse Tribrid MS system.
Project description:Suberoylanilide hydroxamic acid (SAHA) and valproic acid (VPA) are both histone deacetylases inhibitor (HDACi), and are able to attenuate the activation of hepatic stelllate cells. To explore the underlying molecular mechanisms, we performed gene expression profile analyses of human hepatic stellate cell line LX2 treated with SAHA or VPA for 24 hours. Duplicate experiments were performed: Untreated LX2, SAHA treated LX2 and VPA treated LX2.
Project description:Suberoylanilide hydroxamic acid (SAHA) and valproic acid (VPA ) are both histone deacetylases inhibitor (HDACi), and are able to attenuate the activation of hepatic stelllate cells. To explore the underlying molecular mechanisms, we performed miRNA expression profile analyses of human hepatic stellate cell line LX2 treated with SAHA or VPA for 24 hours. Duplicate experiments were performed: Untreated LX2, SAHA treated LX2 and VPA treated LX2.
Project description:This study evaluated primary CD4+ T cell gene expression treated with pharmacologically achievable concentration (340 nM) of SAHA for 24 hours in order to evaluate potential side effects of this compound in cells relevant to HIV infection. Analysis of human primary CD4+ T cells taken from 9 healthy donors treated with 340 nM of SAHA for 24 hours. Results identify genes modulated by SAHA treatment in human primary CD4+ T cells.
Project description:Gastric cancer cell line AGS was treated with suberoylanilide hydroxamic acid (SAHA) for 24 hours. Microarray analysis was done to explore the differentially expressed genes betweenSAHA treated and control cells.