Project description:Small molecule inhibitors of the bromodomain and extraterminal (BET) family of proteins are in clinical trials for a variety of cancers, but patient selection strategies are limited. This is due in part to the heterogeneity of response following BET inhibition (BETi), which includes differentiation, senescence, and cell death in subsets of cancer cell lines. To elucidate the dominant features defining response to BETi, we carried out phenotypic and gene expression analysis of both treatment naïve cell lines and engineered tolerant lines. We found that both de novo and acquired tolerance to BET inhibition are driven by the robustness of the apoptotic response and that genetic or pharmacological manipulation of the apoptotic signaling network can modify the phenotypic response to BETi. We further identify that ordered expression of the apoptotic genes BCL2, BCL2L1, and BAD significantly predicts response to BETi. Our findings highlight the role of the apoptotic network in response to BETi, providing a molecular basis for patient stratification and combination therapies. Gene expression profiling of A375 melanoma cells or NOMO-1 AML cells treated with DMSO or the BET inhibitor, CPI203. Also, gene expression profiling of the respective derived BETi-tolerant cells treated with DMSO or CPI203.
Project description:Acute myeloid leukemia (AML) and acute T-lymphoblastic leukemia (T-ALL) maintain the undifferentiated phenotype and proliferative capacity of their respective cells of origin, hematopoietic stem/progenitor cells and immature thymocytes. The mechanisms that maintain these progenitor-like characteristics are poorly understood. We report that the transcription factor Zfx is required for the development and propagation of experimental AML caused by MLL-AF9 fusion, and of T-ALL caused by Notch1 activation. In both leukemia types, Zfx activated progenitor-associated gene expression programs and prevented differentiation. Key Zfx target genes included mitochondrial enzymes Ptpmt1 and Idh2, whose overexpression partially rescued the propagation of Zfx-deficient AML. These studies identify a common mechanism that controls the cell-of-origin characteristics of acute leukemias derived from disparate lineages and transformation mechanisms. NOMO-1 cells were infected with control and ZFX shRNA lentiviruses at an MOI of 1. RNA was collected for microarrays 48 hours after selection.
Project description:For many years, immortalized cell lines have been used as model systems for cancer research. Cell line panels were established for basic research and drug development, but did not cover the full spectrum of leukemia and lymphoma. Therefore, we now developed a novel panel (LL-100), 100 cell lines covering 22 entities of human leukemia and lymphoma including T-cell, B-cell and myeloid malignancies. Importantly, all cell lines are unequivocally authenticated and assigned to the correct tissue. Cell line samples were proven to be free of mycoplasma and virus contamination. Whole exome sequencing (WES) and RNA sequencing (RNA-seq) of the hundred authenticated leukemia-lymphoma cell lines were conducted with a uniform methodology to complement existing data on these publicly available cell lines. This part captures RNA-Seq. This data set will be useful for understanding the function of oncogenes and tumor suppressor genes and to develop targeted therapies.
Project description:Single-shot proteome analysis of 4 AML cell lines; 2 selinexor sensitive cell lines (GDM-1, MV4-11) and 2 resistant cell lines (NOMO-1 and PL-21) and ex vivo AML cells from 30 patients treated with DMSO (B; before treatment) or 1 uM selinexor (A; after treatment) for 6 hours.
Project description:Proteins are the primary targets of almost all small molecule drugs. However, even the most selectively designed drugs can potentially target several unknown proteins. Identification of potential drug targets can facilitate design of new drugs and repurposing of existing ones. Current state-of-the-art proteomics methodologies enable screening of thousands of proteins against a limited number of drug molecules. Here we report the development of a label-free quantitative proteomics approach that enables proteome-wide screening of small organic molecules in a scalable, reproducible, and rapid manner by streamlining the proteome integral solubility alteration (PISA) assay. We used rat organs ex-vivo to determine organ specific targets of medical drugs and enzyme inhibitors to identify novel drug targets for common drugs such as Ibuprofen. Finally, global drug profiling revealed overarching trends of how small molecules affect the proteome through either direct or indirect protein interactions.
Project description:Pharmacological inhibition of chromatin co-regulatory factors represents a clinically validated strategy to modulate oncogenic signaling through selective attenuation of gene expression. Here, we demonstrate that CBP/EP300 bromodomain inhibition preferentially abrogates the viability of multiple myeloma cell lines. Phenotypic effects are preceded by the direct transcriptional suppression of the lymphocyte-specific transcription factor IRF4 and the subsequent down-regulation of the IRF4 transcriptional program. Ectopic expression of IRF4 antagonizes the phenotypic effects of CBP/EP300 bromodomain inhibition and prevents the suppression of the IRF4 target c-MYC. These findings suggest that CBP/EP300 bromodomain inhibition represents a viable therapeutic strategy for targeting multiple myeloma and other lymphoid malignancies dependent on the IRF4 network. Through the use of CBP/EP300 bromodomain inhibitors (CBP/EP300i), we demonstrate that MYC expression in BETi-resistant cells is dependent on CBP/EP300 bromodomains and that treatment with CBP/EP300i restores phenotypic sensitivity.
Project description:We have performed a Proteogenomics meta-analysis of data sets deposited in ProteomeXchange: PXD000265, PXD000313, PXD000923, PXD001030, PXD001058, PXD002291, PXD002739, PXD002740 and PXD003156 and using 29 RNA-Seq data sets on rice (Oryza sativa). We created a search database comprising translated reads that had been mapped onto the rice genome, as well as officially annotated rice proteins sequences. The RNA Seq database was pre-processed to identify “novel transcripts” for those not mapping fully to an existing exon, and “novel junctions” for those reads mapped with a gap, implying a potential novel splice site that was not annotated in the official gene set. Confidentially identified “novel peptides” i.e. those mapping to a novel junction or novel transcript were post-processed to ensure that there were no other better explanations for the corresponding spectra e.g. peptide from a canonical gene with a modification or amino acid substitution. Data were exported from the pipeline in PSI mzIdentML 1.2 format, containing chromosomal coordinates, and further converted to PSI proBed format for genome visualisation. Novel peptides were searched against other plant databases using BLAST to see if they had predicted in genes from other species. A total of 1584 novel peptides were identified, mapping to ~700 genomic loci in which either new genes have been predicted (~100) or updates to existing gene models have been predicted (~600).
Project description:Bovine purified protein derivative (bPPD) and avian purified protein derivative (aPPD) arewidely used forbovine tuberculosis diagnosis. However, little is known about their qualitative and quantitative characteristics, which makes their standardisation difficult. In addition, bPPDcan give false-positive tuberculosis results because of sequence homologybetween Mycobacterium bovis andM. avium proteins. Here we used proteomics to characterisebPPD, aPPD and an immunopurifiedsubcomplexfrombPPD called P22.