Project description:HeLa cell extracts with or without GSK3 enzyme inhibition were assayed using protein microarrays in order to detect GSK3-dependent changes in protein polyubiquitination.
Project description:HeLa cell extracts with or without GSK3 enzyme inhibition were assayed using protein microarrays in order to detect GSK3-dependent changes in protein polyubiquitination. HeLa lysates in triplicates were supplemented with ubiquitin and incubated on protein microarrays (ProtoArray 5.0; Invitrogen) in the presence or absence of the GSK3 inhibitor SB-216763. Polyubiquitination of the arrayed proteins was detected using specific antibodies. ProtoArray 5.0 contains over 9,000 full-length human proteins purified and arrayed in duplicate under native conditions to maximize functionality.
Project description:<p><strong>INTRODUCTION:</strong> Interesting data about the family Asteraceae as a new source of Leishmania major dihydroorotate dehydrogenase (LmDHODH) inhibitors are presented. This key macromolecular target for parasites causing neglected diseases catalyzes the fourth reaction of the de novo pyrimidine biosynthetic pathway, which takes part in major cell functions, including DNA and RNA biosynthesis.</p><p><strong>OBJECTIVES:</strong> We aimed to (1) determine LmDHODH inhibitor candidates, revealing the type of chemistry underlying such bioactivity, and (2) predict the inhibitory potential of extracts from new untested plant species, classifying them as active or inactive based on their LC-MS based metabolic fingerprints.</p><p><strong>METHODS:</strong> Extracts from 150 species were screened for the inhibition of LmDHODH, and untargeted UHPLC-(ESI)-HRMS metabolomic studies were carried out in combination with in silico approaches.</p><p><strong>RESULTS:</strong> The IC50 values determined for a subset of 59 species ranged from 148 µg/mL to 9.4 mg/mL. Dereplication of the metabolic fingerprints allowed the identification of 48 metabolites. A reliable OPLS-DA model (R2 > 0.9, Q2 > 0.7, RMSECV < 0.3) indicated the inhibitor candidates; nine of these metabolites were identified using data from isolated chemical standards, one of which-4,5-di-O-E-caffeoylquinic acid (IC50 73 µM)-was capable of inhibiting LmDHODH. The predictive OPLS model was also effective, with 60% correct predictions for the test set.</p><p><strong>CONCLUSION:</strong> Our approach was validated for (1) the discovery of LmDHODH inhibitors or interesting starting points for the optimization of new leishmanicides from Asteraceae species and (2) the prediction of extracts from untested species, classifying them as active or inactive.</p>
Project description:Current diagnostics for allergies, such as skin prick and radioallergosorbent tests, do not allow for inexpensive, high-throughput screening of patients. Additionally, extracts used in these methods are made from washed pollen that lacks pollen surface materials that may contain allergens. We sought to develop a high-throughput assay to rapidly measure allergen-specific IgE levels in sera and to explore the relative allergenicity of different pollen fractions (i.e. surface, cytoplasmic, commercial extracts). To do this, we generated a protein microarray containing surface, cytoplasmic, and commercial extracts from 22 pollen species, commercial extracts from nine non-pollen allergens, and five recombinant allergenic proteins. Arrays were incubated with <25uL of serum from 176 individuals and bound IgE was detected by indirect immunofluorescence, providing a high-throughput measurement of IgE levels.
Project description:Histone deacetylase (HDAC) inhibition has been shown in previous studies to disrupt the synovial sarcoma oncoprotein complex, resulting in apoptosis. To understand the molecular effects of HDAC inhibition, RNA-Seq transcriptome analysis was undertaken in six human synovial sarcoma cell lines. HDAC inhibition induced pathways of cell cycle arrest, neuronal differentiation and response to oxygen-containing species, effects also observed in other cancers treated with this class of drugs. More specific to synovial sarcoma, polycomb-group targets were reactivated including tumor suppressor CDKN2A, and pro-apoptotic transcriptional patterns were induced. Functional analyses revealed that ROS-mediated FOXO activation and pro-apoptotic factors BIK, BIM and BMF were important to apoptosis induction following HDAC-inhibition in synovial sarcoma
Project description:Embryonic stem cells (ESCs) can be maintained in the naïve state through inhibition of Mek1/2 and Gsk3 (2i). A relevant effect of 2i is the inhibition of Cdk8/19, which are negative regulators of the Mediator complex, responsible for the activity of enhancers. Inhibition of Cdk8/19 (Cdk8/19i) stimulates enhancers and, similar to 2i, stabilizes ESCs in the naïve state. Here, we use mass spectrometry to describe the molecular events (phosphoproteome, proteome, and metabolome) triggered by 2i and Cdk8/19i on ESCs. Our data reveal widespread commonalities between these two treatments, suggesting overlapping processes. We find that post-transcriptional de-repression by both 2i and Cdk8/19i might support the mitochondrial capacity of naive cells. However, proteome reprogramming in each treatment is achieved by different mechanisms. Cdk8/19i acts directly on the transcriptional machinery, activating key identity genes to promote the naïve program. In contrast, 2i stabilizes the naïve circuitry through, in part, de-phosphorylation of downstream transcriptional effectors.
Project description:Gene expression data of breast cancer samples before and after PI3K inhibition In the study presented here, we evaluated the expression profiles of a total of 105 unique genes in 6 breast cancer samples before and after PI3K-inhibitor therapy
Project description:Epigenetic dysregulation has emerged as an important mechanism in cancer. Alterations in epigenetic machinery have become a major focus for new targeted therapies. The current report describes the discovery and biological activity of a cyclopropylamine containing inhibitor of Lysine Demethylase 1 (LSD1), GSK2879552. This small molecule is a potent, selective, orally bioavailable, mechanism-based irreversible inhibitor of LSD1. A proliferation screen of cell lines representing a number of tumor types indicated that small cell lung carcinoma (SCLC) is sensitive to LSD1 inhibition. The subset of SCLC lines and primary samples that undergo growth inhibition in response to GSK2879552 exhibit DNA hypomethylation of a signature set of probes suggesting this may be used as a predictive biomarker of activity. The targeted mechanism coupled with a novel predictive biomarker make LSD1 inhibition an exciting potential therapy for SCLC, a highly prevalent, rarely cured, tumor type representing approximately 15% of all lung cancers. DNA methylation profiling was performed using Infinium 450K methylation arrays on SCLC cell lines, patient derived xenografts, and patient samples. Data was processed and normalized using GenomeStudio V2011.1