0000000000053985
AUTHOR
James E. Bradner
CRISPR-Cas9 screen reveals a MYCN-amplified neuroblastoma dependency on EZH2.
Pharmacologically difficult targets, such as MYC transcription factors, represent a major challenge in cancer therapy. For the childhood cancer neuroblastoma, amplification of the oncogene MYCN is associated with high-risk disease and poor prognosis. Here, we deployed genome-scale CRISPR-Cas9 screening of MYCN-amplified neuroblastoma and found a preferential dependency on genes encoding the polycomb repressive complex 2 (PRC2) components EZH2, EED, and SUZ12. Genetic and pharmacological suppression of EZH2 inhibited neuroblastoma growth in vitro and in vivo. Moreover, compared with neuroblastomas without MYCN amplification, MYCN-amplified neuroblastomas expressed higher levels of EZH2. ChIP…
Targeting transcriptional addictions in small cell lung cancer with a covalent CDK7 inhibitor.
Small cell lung cancer (SCLC) is an aggressive disease with high mortality, and the identification of effective pharmacological strategies to target SCLC biology represents an urgent need. Using a high-throughput cellular screen of a diverse chemical library, we observe that SCLC is sensitive to transcription-targeting drugs, in particular to THZ1, a recently identified covalent inhibitor of cyclin-dependent kinase 7. We find that expression of super-enhancer-associated transcription factor genes, including MYC family proto-oncogenes and neuroendocrine lineage-specific factors, is highly vulnerability to THZ1 treatment. We propose that downregulation of these transcription factors contribut…
Abstract 1126: Efficacy of BET bromodomain inhibition in Kras-positive non-small cell lung cancer.
Abstract Amplification of MYC is one of the most common genetic alterations in lung cancer, contributing to a myriad of phenotypes associated with growth, invasion and drug resistance. Murine genetics has established both the centrality of somatic alterations of Kras in lung cancer, as well as dependency of Kras-dependent tumors on c-Myc function. Unfortunately, drug-like small-molecule inhibitors of KRAS and c-Myc have yet to be realized. The recent discovery in hematologic malignancies that bromodomain inhibition impairs MYC expression and MYC-dependent transcriptional function prompted the possibility of targeting KRAS-driven NSCLC with a potent, prototypical BET bromodomain inhibitor, J…
Oncogenic Deregulation of EZH2 as an Opportunity for Targeted Therapy in Lung Cancer.
Abstract As a master regulator of chromatin function, the lysine methyltransferase EZH2 orchestrates transcriptional silencing of developmental gene networks. Overexpression of EZH2 is commonly observed in human epithelial cancers, such as non–small cell lung carcinoma (NSCLC), yet definitive demonstration of malignant transformation by deregulated EZH2 remains elusive. Here, we demonstrate the causal role of EZH2 overexpression in NSCLC with new genetically engineered mouse models of lung adenocarcinoma. Deregulated EZH2 silences normal developmental pathways, leading to epigenetic transformation independent of canonical growth factor pathway activation. As such, tumors feature a transcrip…
Synthesis of hybrid anticancer agents based on kinase and histone deacetylase inhibitors
Fragments based on the VEGFR2i Semaxanib (SU5416, (vascular endothelial growth factor receptor-2\ud inhibitor) and the HDACi (histone deacetylase inhibitor) SAHA (suberanilohydroxamic acid) have been\ud merged to form a range of low molecular weight dual action hybrids. Vindication of this approach is\ud provided by SAR, docking studies, in vitro cancer cell line and biochemical enzyme inhibition data as well\ud as in vivo Xenopus data for the lead molecule (Z)-N1-(3-((1H-pyrrol-2-yl)methylene)-2-oxoindolin-5-yl)-\ud N8-hydroxyoctanediamide 6.
Efficacy of BET Bromodomain Inhibition in Kras-Mutant Non–Small Cell Lung Cancer
Abstract Purpose: Amplification of MYC is one of the most common genetic alterations in lung cancer, contributing to a myriad of phenotypes associated with growth, invasion, and drug resistance. Murine genetics has established both the centrality of somatic alterations of Kras in lung cancer, as well as the dependency of mutant Kras tumors on MYC function. Unfortunately, drug-like small-molecule inhibitors of KRAS and MYC have yet to be realized. The recent discovery, in hematologic malignancies, that bromodomain and extra-terminal (BET) bromodomain inhibition impairs MYC expression and MYC transcriptional function established the rationale of targeting KRAS-driven non–small cell lung cance…