Co-inhibition of BET proteins and PI3Kα triggers mitochondrial apoptosis in rhabdomyosarcoma cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE145469 | GEO | 2020/02/19
REPOSITORIES: GEO
Similar Datasets
Project description:Targeting BET bromodomain proteins utilizing small molecules in an emerging anti-cancer strategy with clinical evaluation of at least six inhibitors now underway. While MYC downregulation was initially proposed as a key mechanistic property of BET inhibitors, recent evidence suggests that additional anti-tumor activities are important. Using the Eμ-Myc model of B-cell lymphoma we demonstrate that BET inhibition with JQ1 is a potent inducer of p53-independent apoptosis that occurs in the absence of effects on Myc gene expression. JQ1 skews the expression of pro-apoptotic (Bim) and anti-apoptotic (BCL-2/BCL-xL) BCL-2 family members to directly engage the mitochondrial apoptotic pathway. Consistent with this, Bim knockout or Bcl-2 overexpression inhibited apoptosis induction by JQ1. We identified lymphomas that were either intrinsically resistant to JQ1-mediated death or acquired resistance following in vivo exposure. Strikingly, in both instances BCL-2 was strongly upregulated and was concomitant with activation of RAS pathways. Eμ-Myc lymphomas engineered to express activated Nras upregulated BCL-2 and acquired a JQ1-resistance phenotype. These studies provide important information on mechanisms apoptosis induction and resistance to BET-inhibition, while providing further rationale for the translation of BET inhibitors in aggressive B-cell lymphomas.
2016-09-18 | GSE87050 | GEO
Project description:The aim of our study was to investigate PIK3CA collaborative mutations that result in resistance to BYL719, a PI3Kα selective inhibitor. One of the tumor suppressor genes discovered was neurofibromin 1 (NF1). Using shRNA-mediated knockdown and CRISPR/Cas9-mediated knockout of NF1 in murine and human PIK3CAH1047R cell lines and a patient derived xenograft organoid model, we found that NF1 loss reduces sensitivity to PI3Kα inhibition. By looking at differentially expressed genes we wanted to investigate the effect of NF1 KO in T47D cells and if they respond differentially to BYL719 compared to the T47D CTRL cells.
2023-03-16 | GSE207514 | GEO
Project description:The aim of our study was to investigate PIK3CA collaborative mutations that result in resistance to BYL719, a PI3Kα selective inhibitor. One of the tumor suppressor genes discovered was neurofibromin 1 (NF1). Using shRNA-mediated knockdown and CRISPR/Cas9-mediated knockout of NF1 in murine and human PIK3CAH1047R cell lines and a patient derived xenograft organoid model, we found that NF1 loss reduces sensitivity to PI3Kα inhibition. By looking at differentially expressed genes we wanted to investigate the effect of NF1 KO in T47D cells and if they respond differentially to BYL719 compared to the T47D CTRL cells.
2023-03-16 | GSE207513 | GEO
Project description:The aim of our study was to investigate PIK3CA collaborative mutations that result in resistance to BYL719, a PI3Kα selective inhibitor. One of the tumor suppressor genes discovered was neurofibromin 1 (NF1). Using shRNA-mediated knockdown and CRISPR/Cas9-mediated knockout of NF1 in murine and human PIK3CAH1047R cell lines and a patient derived xenograft organoid model, we found that NF1 loss reduces sensitivity to PI3Kα inhibition. By looking at differentially expressed genes we wanted to investigate the effect of NF1 KO in T47D cells and if they respond differentially to BYL719 compared to the T47D CTRL cells.
2023-03-16 | GSE207512 | GEO
Project description:Phosphoinositide-3-kinase (PI3K)-α inhibitors are clinically active in squamous carcinoma (SCC) of the head and neck (H&N) bearing mutations or amplification of PIK3CA. We aimed to identify potential mechanism of resistance and have observed that SCCs cells overcome the antitumor effects of the PI3Kα inhibitor BYL719 by maintaining PI3K-independent activation of the mammalian target of rapamycin (mTOR). The persistent mTOR activation is mediated by the tyrosine kinase receptor AXL. We found that AXL is overexpressed in resistant tumors, dimerizes with the epidermal growth factor receptor (EGFR), phosphorylates EGFR tyrosine 1173, resulting in activation of phospholipase Cγ (PLCγ)- protein kinase C (PKC) that, in turn, activates mTOR. Finally, simultaneous treatment with PI3Kα and either EGFR, AXL or PKC inhibitors reverts this resistance. RNAseq from acquired resistant cells CAL33B, K180B were compared to their parental counterpart CAL33 and K180, respectively. K180 is a shortcut of KYSE180, and B stands for BYL719. Duplicate of parental sensitive cells and K180B, and triplicate for CAL33B.
2015-04-12 | E-GEOD-61515 | biostudies-arrayexpress
Project description:JQ1 is a BET-bromodomain inhibitor that has immunomodulatory effects. However, the precise molecular mechanism that JQ1 targets to elicit changes in antibody production is not understood. Our results show that JQ1 induces apoptosis, reduces cell proliferation, and as a consequence, inhibits antibody secreting cell differentiation. ChIP-sequencing reveals a selective displacement of Brd4 in response to acute JQ1 treatment (<2 hours), resulting in specific transcriptional repression. After 8 hours, subsequent alterations in gene expression arose as a result of global loss of Brd4 occupancy. We demonstrate that apoptosis induced by JQ1 was solely attributed to the pro-apoptotic protein Bim (Bcl2l11). Conversely, cell cycle regulation by JQ1 was associated with multiple Myc-associated gene targets. Our results demonstrate that JQ1 drives temporal changes in Brd4 displacement that results in a specific transcriptional profile that directly affects B cell survival and proliferation to modulate the humoral immune response.
2020-08-13 | GSE156126 | GEO
Project description:Background: The present study investigated a role of proteins from BET family (epigenetic readers) in schizophrenia-like abnormalities in MAM-E17 model of schizophrenia. Methods: An inhibitor of BET proteins, JQ1, was given during adolescence in postnatal days (P) 23-P30, and behavioral response (sensorimotor gating, recognition memory) and prefrontal cortex (mPFC) function (long-term potentiation (LTP), molecular and proteomic studies) were performed in adult males and females. Results: Deficits in sensorimotor gating and recognition memory were observed only in MAM-treated males. However, adolescent JQ1 treatment affected control, but MAM-treated groups in both sexes. Electrophysiological study showed an LTP impairment only in male MAM-treated animals, and JQ1 did not have any effect on LTP in the mPFC. In contrast, MAM did not affect immediate early gene expression (markers of neuronal and synaptic activity), but JQ1 altered them in both sexes. Proteomic study revealed alterations in MAM-treated groups only in males, while JQ1 affected both sexes. Conclusions: Prenatal MAM administration induced schizophrenia-like abnormalities only in males. In contrast, adolescent JQ1 treatment affected both sexes and induced behavioral changes in control groups, altered a markers of neuronal and synaptic activity and proteomic landscape in the mPFC of both groups (VEH- and MAM-treated). Thus, adolescent inhibition of BET family might change neuroplasticity in the mPFC.
2021-09-07 | PXD027050 | Pride
Project description:To determine the global transcriptome changes in mantle cell lymphoma cells following treatment with the BET bromodomain antagonist, JQ1 Mantle Cell Lymphoma (MCL) cells exhibit increased B cell receptor and NFkB activities. The BET protein BRD4 is essential for the transcriptional activity of NFkB. Here, we demonstrate that treatment with the BET protein bromodomain antagonist (BA) JQ1 attenuates MYC and CDK4/6, inhibits the nuclear RelA levels and the expression of NFκB target genes including Brutonâs Tyrosine Kinase (BTK) in MCL cells. While lowering the levels of the anti-apoptotic BCL2 family proteins, BA treatment induces the pro-apoptotic protein BIM and exerts dose-dependent lethality against cultured and primary MCL cells. Co-treatment with BA and the BTK inhibitor ibrutinib synergistically induces apoptosis of MCL cells. Compared to each agent alone, co-treatment with BA and ibrutinib markedly improved the median survival of mice engrafted with the MCL cells. BA treatment also induced apoptosis of the in vitro isolated, ibrutinib-resistant MCL cells which overexpress CDK6, BCL2, Bcl-xL, XIAP and AKT, but lack ibrutinib resistance-conferring BTK mutation. Co-treatment with BA and panobinostat (pan-histone deacetylase inhibitor) or palbociclib (CDK4/6 inhibitor) or ABT-199 (BCL2 antagonist) synergistically induced apoptosis of the ibrutinib-resistant MCL cells. These findings highlight and support further in vivo evaluation of the efficacy of the BA-based combinations with these agents against MCL, including ibrutinib-resistant MCL. MO2058 cells treated with vehicle, 250 nM or 1000 nM JQ1 for 8 hours. Samples were acquired and analyzed in duplicate.
2015-12-31 | E-GEOD-70651 | biostudies-arrayexpress
Project description:Phosphoinositide-3-kinase (PI3K)-α inhibitors are clinically active in squamous carcinoma (SCC) of the head and neck (H&N) bearing mutations or amplification of PIK3CA. We aimed to identify potential mechanism of resistance and have observed that SCCs cells overcome the antitumor effects of the PI3Kα inhibitor BYL719 by maintaining PI3K-independent activation of the mammalian target of rapamycin (mTOR). The persistent mTOR activation is mediated by the tyrosine kinase receptor AXL. We found that AXL is overexpressed in resistant tumors, dimerizes with the epidermal growth factor receptor (EGFR), phosphorylates EGFR tyrosine 1173, resulting in activation of phospholipase Cγ (PLCγ)- protein kinase C (PKC) that, in turn, activates mTOR. Finally, simultaneous treatment with PI3Kα and either EGFR, AXL or PKC inhibitors reverts this resistance.
2015-04-12 | GSE61515 | GEO
Project description:Background: We hypothesized that spleen microarray gene expression profiles analyzed with contemporary pathway analysis software would provide molecular pathways of interest and target genes that might help explain the affect of bcl-2 on improving survival during sepsis. Methods: Two mouse models of sepsis, cecal ligation and puncture and tracheal instillation of Pseudomonas aeruginosa, were tested in both wild-type mice and mice that overexpress bcl-2. Whole spleens were obtained 6 hours after septic injury. DNA microarray transcriptional profiles were obtained using the Affymetrix 430A GeneChip, containing 22,690 elements. Ingenuity Pathway Analysis software was used to construct hypothetical transcriptional networks that changed in response to sepsis and expression of the bcl-2 transgene. Results: A conservative approach was used wherein only changes induced by both abdominal and pulmonary sepsis were studied. At 6 hours, sepsis induced alterations in the abundance of hundreds of spleen genes, including a number of proinflammatory mediators (e.g., IL-6). These sepsis-induced alterations were blocked by expression of the bcl-2 transgene. Network analysis implicated a number of bcl-2-related apoptosis genes, including bcl2L11 (bim), bcl-2L2 (bcl-w), bmf, and mcl-1. Sepsis in bcl-2 transgenic animals resulted in alteration of RNA abundance for only a single gene, ceacam1. Conclusion: These findings are consistent with sepsis-induced alterations in the balance of pro- and anti-apoptotic transcriptional networks. In addition, our data suggest that the ability of bcl-2 overexpression to improve survival in sepsis in this model is related in part to prevention of sepsis-induced alterations in spleen transcriptional responses. Keywords: Sepsis, bcl-2, wildtype, spleen, RNA expression, microarray
2007-02-15 | GSE5811 | GEO