Similar Datasets
Project description:Notch activation is highly prevalent in several cancers, including more than 60% of cases of T-cell acute lymphoblastic leukemia (T-ALL). However, the use of pan-Notch inhibitors to treat cancers has been hampered by excessive toxicities, particularly affecting intestinal health. In order to combat Notch-driven oncogenic signals with less toxicity, one strategy is to target the transcriptional cofactors that promote tissue-specific Notch activation. We previously showed that Zmiz1 is a direct Notch1 cofactor that selectively promotes T-cell development and leukemogenic functions of Notch1. Ets1 is an excellent candidate as a transcription factor (TF) that promotes Notch functions selectively in T-ALL since the scope of Ets1 expression is far more limited than Notch expression and since Ets1 co-occupies Notch-bound enhancers with high frequency. Here, we used comparative ChIP-Seq and gene expression methods to show that Ets1 withdrawal impaired Notch complex recruitment and H3K27 acetylation at co-bound enhancers and disabled shared oncogenic pathways. ChIP-Seq showed that Ets1 peaks overlapped with 73-76% of Zmiz1 peaks and 71-75% of Notch1 peaks. Ets1 knockdown reduced Notch1, Rbpj, and Zmiz1 occupancy at enhancers that regulate genes that drive T-cell differentiation and/or T-ALL proliferation. RNA-Seq showed that Ets1 coregulated ~22% of Notch target genes with induction of Myc as a dominant and functional contribution. Our data support an emerging model in which transcription factors like Ets1 assist Notch in activating a subset of enhancers with important functions for T-cell leukemogenesis and development. Strategies that exploit the context dependence of Notch might combat the Notch pathway in cancer cells with less toxicity than pan-Notch inhibitors.
2020-07-07 | GSE138659 | GEO
Project description:Notch activation is highly prevalent in several cancers, including more than 60% of cases of T-cell acute lymphoblastic leukemia (T-ALL). However, the use of pan-Notch inhibitors to treat cancers has been hampered by excessive toxicities, particularly affecting intestinal health. In order to combat Notch-driven oncogenic signals with less toxicity, one strategy is to target the transcriptional cofactors that promote tissue-specific Notch activation. We previously showed that Zmiz1 is a direct Notch1 cofactor that selectively promotes T-cell development and leukemogenic functions of Notch1. Ets1 is an excellent candidate as a transcription factor (TF) that promotes Notch functions selectively in T-ALL since the scope of Ets1 expression is far more limited than Notch expression and since Ets1 co-occupies Notch-bound enhancers with high frequency. Here, we used comparative ChIP-Seq and gene expression methods to show that Ets1 withdrawal impaired Notch complex recruitment and H3K27 acetylation at co-bound enhancers and disabled shared oncogenic pathways. ChIP-Seq showed that Ets1 peaks overlapped with 73-76% of Zmiz1 peaks and 71-75% of Notch1 peaks. Ets1 knockdown reduced Notch1, Rbpj, and Zmiz1 occupancy at enhancers that regulate genes that drive T-cell differentiation and/or T-ALL proliferation. RNA-Seq showed that Ets1 coregulated ~22% of Notch target genes with induction of Myc as a dominant and functional contribution. Our data support an emerging model in which transcription factors like Ets1 assist Notch in activating a subset of enhancers with important functions for T-cell leukemogenesis and development. Strategies that exploit the context dependence of Notch might combat the Notch pathway in cancer cells with less toxicity than pan-Notch inhibitors.
2020-07-07 | GSE138516 | GEO
Project description:Ets1 confers context-dependent activation of Notch signaling in T-cell leukemia
| PRJNA576685 | ENA
Project description:Ets1 confers context-dependent activation of Notch signaling in T-cell leukemia [ChIP-Seq]
| PRJNA576230 | ENA
Project description:Ets1 confers context-dependent activation of Notch signaling in T-cell leukemia [RNA-Seq]
| PRJNA576692 | ENA
Project description:This SuperSeries is composed of the SubSeries listed below.
2023-08-12 | GSE240224 | GEO
Project description:Resistance of tumor cells to chemoradiotherapy represents a fundamental problem in clinical oncology. The underlying mechanisms are actively debated. Here we show that blocking inflammatory cytokine receptor signaling via STAT3 re-sensitized treatment-refractory cancer cells and abolished tumor growth in a xenograft mouse model when applied together with chemoradiotherapy. STAT3 executed treatment resistance by triggering the expression of RBPJ, the key transcriptional regulator of the NOTCH pathway. The mandatory RBPJ interaction partner, NOTCH intracellular domain, was provided by tumor cell-intrinsic expression of NOTCH ligands that caused tonic NOTCH proteolysis. In fact, NOTCH inhibition phenocopied the effect of blocking STAT3 signaling. Moreover, genetic profiling of rectal cancer patients revealed the importance of the STAT3/NOTCH axis as NOTCH expression correlated with clinical outcome. Our data uncovered an unprecedented signal alliance between inflammation and cellular development that orchestrated resistance to chemoradiotherapy. Clinically, our findings allow for biomarker-driven patient stratification and offer novel treatment options.
| S-EPMC7865718 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2011-05-12 | E-GEOD-27833 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2020-04-23 | GSE149159 | GEO
Project description:Aberrant activation of the NOTCH signaling pathway is crucial for the onset and progression of T cell leukemia. Yet recent studies also suggest a tumor suppressive role of NOTCH signaling in acute myeloid leukemia (AML) and reactivation of this pathway offers an attractive opportunity for anti-AML therapies. N-methylhemeanthidine chloride (NMHC) is a novel Amaryllidaceae alkaloid that we previously isolated from Zephyranthes candida, exhibiting inhibitory activities in a variety of cancer cells, particularly those from AML. Here, we report NMHC not only selectively inhibits AML cell proliferation in vitro but also hampers tumor development in a human AML xenograft model. Genome-wide gene expression profiling reveals that NMHC activates the NOTCH signaling. Combination of NMHC and recombinant human NOTCH ligand DLL4 achieves a remarkable synergistic effect on NOTCH activation. Moreover, pre-inhibition of NOTCH by overexpression of dominant negative MAML alleviates NMHC-mediated cytotoxicity in AML. Further mechanistic analysis using structure-based molecular modeling as well as biochemical assays demonstrates that NMHC docks in the hydrophobic cavity within the NOTCH1 negative regulatory region (NRR), thus promoting NOTCH1 proteolytic cleavage. Our findings thus establish NMHC as a potential NOTCH agonist that holds great promises for future development as a novel agent beneficial to patients with AML.
| S-EPMC4876435 | biostudies-literature