Promiscuous targeting of bromodomains by Bromosporine identifies BET proteins as master regulators of primary transcription response in leukemia
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE78830 | GEO | 2016/10/25
SECONDARY ACCESSION(S): PRJNA314074
REPOSITORIES: GEO
Similar Datasets
Project description:Bromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET (bromo and extra-terminal) inhibitors and their significant activity in diverse tumor models have rapidly translated into clinical studies and have motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of BRD protein complexes complicates predictions of the consequences of their pharmacological targeting. To address this issue, we developed a promiscuous BRD inhibitor [bromosporine (BSP)] that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle, we studied the effects of BSP on leukemic cell lines known to be sensitive to BET inhibition and found, as expected, strong antiproliferative activity. Comparison of the modulation of transcriptional profiles by BSP after a short exposure to the inhibitor resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, nonselective targeting of BRDs identified BETs, but not other BRDs, as master regulators of context-dependent primary transcription response.
| S-EPMC5061470 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2016-10-25 | E-GEOD-78830 | biostudies-arrayexpress
Project description:Bromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET inhibitors and their significant activity in diverse tumor models has rapidly translated into clinical studies and has motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of bromodomain protein complexes complicates predictions of consequences of their pharmacological targeting. To address this issue we developed a promiscuous bromodomain inhibitor (bromosporine, BSP) that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle we studied the effect of BSP in leukemic cell-lines known to be sensitive to BET inhibition and found as expected strong anti-proliferative activity. Comparison of the modulation of transcriptional profiles by BSP at short inhibitor exposure resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, non-selective targeting of BRDs identified BETs, but not other BRDs, as master regulators of a context dependent primary transcription response. Cells were seeded the day prior to treatment at 2x10^5 per ml. Treatments were performed so that a final concentration of 0.1 % DMSO (Cat.#D1435; Sigma) was achieved and cells were incubated with DMSO or 500 nM test compound (BSP, JQ1, LP99, GSK2801, iCBP112 or OF1) for 6 h prior to isolation of RNA. Total RNA was isolated using a standard TRIzol (Invitrogen) protocol and prepared using RNeasy columns (Cat.#74106 plus; Qiagen). RNA was quantified using a Nanodrop spectrophotometer (model ND1000; Thermo Fisher) and integrity assessed on a BioAnalyzer (2100; Agilent Laboratories, USA). All samples had a RNA Integrity Number (RIN) ⥠9. Biological triplicates were performed for each condition tested.
2016-10-25 | E-GEOD-78829 | biostudies-arrayexpress
Project description:Bromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET inhibitors and their significant activity in diverse tumor models has rapidly translated into clinical studies and has motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of bromodomain protein complexes complicates predictions of consequences of their pharmacological targeting. To address this issue we developed a promiscuous bromodomain inhibitor (bromosporine, BSP) that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle we studied the effect of BSP in leukemic cell-lines known to be sensitive to BET inhibition and found as expected strong anti-proliferative activity. Comparison of the modulation of transcriptional profiles by BSP at short inhibitor exposure resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, non-selective targeting of BRDs identified BETs, but not other BRDs, as master regulators of a context dependent primary transcription response. Cells were seeded the day prior to treatment at 2x10^5 per ml. Treatments were performed so that a final concentration of 0.1 % DMSO (Cat.#D1435; Sigma) was achieved and cells were incubated with DMSO or 500 nM test compound (BSP or JQ1) for 6 h prior to isolation of RNA. Total RNA was isolated using a standard TRIzol (Invitrogen) protocol and prepared using RNeasy columns (Cat.#74106 plus; Qiagen). RNA was quantified using a Nanodrop spectrophotometer (model ND1000; Thermo Fisher) and integrity assessed on a BioAnalyzer (2100; Agilent Laboratories, USA). All samples had a RNA Integrity Number (RIN) â?¥ 9. Biological triplicates were performed for each condition tested.
2016-10-25 | E-GEOD-78827 | biostudies-arrayexpress
Project description:Bromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET inhibitors and their significant activity in diverse tumor models has rapidly translated into clinical studies and has motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of bromodomain protein complexes complicates predictions of consequences of their pharmacological targeting. To address this issue we developed a promiscuous bromodomain inhibitor (bromosporine, BSP) that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle we studied the effect of BSP in leukemic cell-lines known to be sensitive to BET inhibition and found as expected strong anti-proliferative activity. Comparison of the modulation of transcriptional profiles by BSP at short inhibitor exposure resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, non-selective targeting of BRDs identified BETs, but not other BRDs, as master regulators of a context dependent primary transcription response.
2016-10-25 | GSE78829 | GEO
Project description:Bromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET inhibitors and their significant activity in diverse tumor models has rapidly translated into clinical studies and has motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of bromodomain protein complexes complicates predictions of consequences of their pharmacological targeting. To address this issue we developed a promiscuous bromodomain inhibitor (bromosporine, BSP) that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle we studied the effect of BSP in leukemic cell-lines known to be sensitive to BET inhibition and found as expected strong anti-proliferative activity. Comparison of the modulation of transcriptional profiles by BSP at short inhibitor exposure resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, non-selective targeting of BRDs identified BETs, but not other BRDs, as master regulators of a context dependent primary transcription response.
2016-10-25 | GSE78827 | GEO
Project description:Promiscuous targeting of bromodomains by Bromosporine identifies BET proteins as master regulators of primary transcription response in leukemia
| PRJNA314074 | ENA
Project description:Targeting bromodomains (BRDs) of the bromo-and-extra-terminal (BET) family offers opportunities for therapeutic intervention in cancer and other diseases. Here, we profile the interactomes of BRD2, BRD3, BRD4, and BRDT following treatment with the pan-BET BRD inhibitor JQ1, revealing broad rewiring of the interaction landscape, with three distinct classes of behavior for the 603 unique interactors identified. A group of proteins associate in a JQ1-sensitive manner with BET BRDs through canonical and new binding modes, while two classes of extra-terminal (ET)-domain binding motifs mediate acetylation-independent interactions. Last, we identify an unexpected increase in several interactions following JQ1 treatment that define negative functions for BRD3 in the regulation of rRNA synthesis and potentially RNAPII-dependent gene expression that result in decreased cell proliferation. Together, our data highlight the contributions of BET protein modules to their interactomes allowing for a better understanding of pharmacological rewiring in response to JQ1.
| S-EPMC6375729 | biostudies-literature
Project description:The MYC transcription factor is a master regulator of diverse cellular functions and has been long considered a compelling therapeutic target because of its role in a range of human malignancies. However, pharmacologic inhibition of MYC function has proven challenging because of both the diverse mechanisms driving its aberrant expression and the challenge of disrupting protein-DNA interactions. Here, we demonstrate the rapid and potent abrogation of MYC gene transcription by representative small molecule inhibitors of the BET family of chromatin adaptors. MYC transcriptional suppression was observed in the context of the natural, chromosomally translocated, and amplified gene locus. Inhibition of BET bromodomain-promoter interactions and subsequent reduction of MYC transcript and protein levels resulted in G(1) arrest and extensive apoptosis in a variety of leukemia and lymphoma cell lines. Exogenous expression of MYC from an artificial promoter that is resistant to BET regulation significantly protected cells from cell cycle arrest and growth suppression by BET inhibitors. MYC suppression was accompanied by deregulation of the MYC transcriptome, including potent reactivation of the p21 tumor suppressor. Treatment with a BET inhibitor resulted in significant antitumor activity in xenograft models of Burkitt's lymphoma and acute myeloid leukemia. These findings demonstrate that pharmacologic inhibition of MYC is achievable through targeting BET bromodomains. Such inhibitors may have clinical utility given the widespread pathogenetic role of MYC in cancer.
| S-EPMC3189078 | biostudies-literature
Project description:The characterization of kinases as oncogenic drivers has led to more than 30 FDA-approved targeted kinase inhibitors for cancer treatment. Unfortunately, these therapeutics fail to have clinical durability because of adaptive responses from the kinome and transcriptome that bypass inhibition of the targeted pathway. In our recent work, we describe a method to prevent these adaptive responses at an epigenetic level, generating a durable response to kinase inhibition.
| S-EPMC4845204 | biostudies-other