Project description:We developed a general approach to small molecule library screening called GE-HTS (Gene Expression-Based High Throughput Screening) in which a gene expression signature is used as a surrogate for cellular states and applied it to the identification of compounds inducing the differentiation of acute myeloid leukemia cells. In screening 1,739 compounds, we identified 8 that reliably induced the differentiation signature, and furthermore yielded functional evidence of bona fide differentiation. This SuperSeries is composed of the following subset Series:; GSE976: Gene Expression-Based High Throughput Screening: APL Treatment with Candidate Compounds; GSE982: Gene Expression-Based High Throughput Screening: HL-60 Cell Treatment with Candidate Compounds; GSE983: Gene Expression-Based High Throughput Screening: Primary Patient AML Blasts, Normal Neutrophils, and Normal Monocytes; GSE985: Gene Expression-Based High Throughput Screening: HL-60 Cells Treated with ATRA and PMA Experiment Overall Design: Refer to individual Series
Project description:We developed a general approach to small molecule library screening called GE-HTS (Gene Expression-Based High Throughput Screening) in which a gene expression signature is used as a surrogate for cellular states and applied it to the identification of compounds inducing the differentiation of acute myeloid leukemia cells. In screening 1,739 compounds, we identified 8 that reliably induced the differentiation signature, and furthermore yielded functional evidence of bona fide differentiation. This SuperSeries is composed of the SubSeries listed below.
Project description:Targeting aberrant epigenetic programs that drive tumorigenesis is a promising approach to cancer therapy. DNA-encoded small-molecule library (DEL) screening is a core platform technology increasingly used to identify drugs that bind to protein targets. Here, we use DEL screening against bromodomain and extra-terminal motif (BET) proteins to identify inhibitors with new chemotypes, and successfully identified BBC1115 as a selective BET inhibitor. While BBC1115 does not structurally resemble OTX-015, a clinically active pan-BET inhibitor, our intensive computational modeling and biological characterization revealed that BBC1115 binds to BET protein BRD4 and suppresses aberrant cell fate programs. Phenotypically, BBC1115-mediated BET inhibition impaired proliferation in acute myeloid leukemia, pancreatic, and colorectal cancer cells in vitro. Moreover, intravenous administration of BBC1115 inhibited subcutaneous pancreatic and colorectal cancer xenograft growth with minimal toxicity and favorable pharmacokinetic properties in vivo. Since epigenetic regulations are ubiquitously employed across normal and malignant cells, it will be critical to evaluate whether BBC1115 interferes with normal cellular functions. Nonetheless, our study implicates that integrating DEL-based small-molecule compound screening and multi-step biological validation represents a reliable strategy to discover new chemotypes with selectivity, efficacy, and safety profiles for targeting proteins involved in epigenetic regulation in human malignancies.
Project description:Targeting aberrant epigenetic programs that drive tumorigenesis is a promising approach to cancer therapy. DNA-encoded small-molecule library (DEL) screening is a core platform technology increasingly used to identify drugs that bind to protein targets. Here, we use DEL screening against bromodomain and extra-terminal motif (BET) proteins to identify inhibitors with new chemotypes, and successfully identified BBC1115 as a selective BET inhibitor. While BBC1115 does not structurally resemble OTX-015, a clinically active pan-BET inhibitor, our intensive computational modeling and biological characterization revealed that BBC1115 binds to BET protein BRD4 and suppresses aberrant cell fate programs. Phenotypically, BBC1115-mediated BET inhibition impaired proliferation in acute myeloid leukemia, pancreatic, and colorectal cancer cells in vitro. Moreover, intravenous administration of BBC1115 inhibited subcutaneous pancreatic and colorectal cancer xenograft growth with minimal toxicity and favorable pharmacokinetic properties in vivo. Since epigenetic regulations are ubiquitously employed across normal and malignant cells, it will be critical to evaluate whether BBC1115 interferes with normal cellular functions. Nonetheless, our study implicates that integrating DEL-based small-molecule compound screening and multi-step biological validation represents a reliable strategy to discover new chemotypes with selectivity, efficacy, and safety profiles for targeting proteins involved in epigenetic regulation in human malignancies.
Project description:Signals from the microenvironment are known to be critical for development, sustaining adult stem cells, and for oncogenic progression. While candidate niche-driven signals that can promote cancer progression have been identified, concerted efforts to comprehensively map microenvironmental ligands for cancer stem cell specific surface receptors have been lacking. Here, we use temporal single cell RNA-sequencing to identify molecular cues from the bone marrow stromal niche that engage leukemia stem cells (LSC) during oncogenic progression. We integrate these data with our RNA-seq analysis of human LSCs from distinct aggressive myeloid cancer subtypes and our CRISPR based in vivo LSC dependency map7 to develop a temporal receptor-ligand interactome essential for disease progression. These analyses identify the taurine transporter (TauT)-taurine axis as a critical dependency of myeloid malignancies. We show that taurine production is restricted to the osteolineage population during cancer initiation and expansion. Inhibiting taurine synthesis in osteolineage cells impairs LSC growth in vitro and improves survival outcomes in vivo. Using TauT genetic loss of function murine models and patient-derived AML cells, we show that TauT inhibition significantly impairs in vivo myeloid leukemia progression. Consistent with elevated TauT expression in venetoclax resistant AML, TauT inhibition synergizes with venetoclax to block growth of primary human AML cells. Mechanistically, our metabolomic, proteomic and transcriptomic approaches indicate that loss of taurine uptake inhibits Rag-GTP dependent mTOR activation and downstream glycolytic metabolism. Collectively, our work establishes the temporal landscape of stromal signals during leukemia progression and identifies taurine as an important regulator of myeloid malignancies.
Project description:Disruption of alternative splicing frequently causes or contributes to human diseases and disorders. Consequently, there is a need for efficient and sensitive reporter assays capable of screening chemical libraries for compounds with efficacy in modulating important splicing events. Here, we describe a screening workflow employing dual Nano and Firefly luciferase alternative splicing reporters that affords highly efficient, sensitive, and linear detection of small molecule responses. Applying this system to a screen of ~95,000 small molecules, we identify compounds that selectively activate or repress a neuronal microexon network that is frequently disrupted in autism and overexpressed in neuroendocrine cancers. Remarkably, among the most potent and selective activating compounds are histone deacetylase (HDAC) inhibitors. We thus describe a high-throughput screening system for candidate splicing therapeutics, a resource of small molecule modulators of microexons, and insight into the mode of action and potential utility of HDAC inhibitors in the context of neurological disorders.