Project description:ChIP-Seq of RNA Polymerase II, and transcriptional regulators in multiple myeloma (MM.1S), glioblastoma (U87-MG), and small cell lung carcinoma (H2171) treated with the BET bromodomain inhibitor JQ1. Cell lines (MM.1S, U87-MG, and H2171) representing multiple myeloma, glioblastoma, and small cell lung carcinoma, were treated with varying concentrations (5nM to 5µM) of the BET bromodomain inhibitor JQ1 followed by ChIP-Seq for RNA Polymerase II and transcriptional regulators. Other datasets from this series of experiments have been release as a part of GSE42355.
Project description:We found that a small molecule inhibitor of PRMT4 inhibited cell growth of a subset of multiple myeloma cell lines. To identify biomarkers that predict the sensitivity of myeloma cells to PRMT4 inhibition, we performed transcriptomic analysis of multiple myeloma cell lines.
Project description:ChIP-Seq of RNA Polymerase II, and transcriptional regulators in multiple myeloma (MM.1S), glioblastoma (U87-MG), and small cell lung carcinoma (H2171) treated with the BET bromodomain inhibitor JQ1.
Project description:Three triple negative breast cancer cell lines (MDAMB231, SUM159, and HCC1806) were treated with small molecule inhibitors (JQ1, BET bromodomain inhibitor; GSK2801, BAZ2A/B bromodomain inhibitor) or BAZ siRNA alone and in combination with JQ1 for 48 hours
Project description:Three triple negative breast cancer cell lines (MDAMB231, SUM159, and HCC1806) were treated with small molecule inhibitors (JQ1, BET bromodomain inhibitor; GSK2801, BAZ2A/B bromodomain inhibitor) alone and in combination for 72 hours
Project description:JQ1 is a small-molecule (BET family) bromodomain inhibitor that causes a contraceptive effect in mice by blocking spermatogenesis and reducing sperm motility.
Project description:Type II testicular germ cell cancers (GCC) are the most frequently diagnosed tumors in young men (20 - 40 years) and are classified as seminoma or non-seminoma. GCCs are commonly treated by orchiectomy and chemo- or radiotherapy. However, a subset of metastatic non-seminomas display only incomplete remission or relapse and require novel treatment options. Recent studies have shown effective application of the small-molecule inhibitor JQ1 in tumor therapy, which interferes with the function of bromodomain and extra-terminal (BET)-proteins. Here, we demonstrate that upon JQ1 doses ≥ 250 nM GCC cell lines and Sertoli cells display compromised survival and induction of cell cycle arrest. JQ1 treated GCC cell lines display upregulation of genes indicative for DNA damage and a cellular stress response. Additionally, downregulation of pluripotency factors and induction of mesodermal differentiation was detected. GCCs xenografted in vivo showed a reduction in tumor size, proliferation and angiogenesis when subjected to JQ1 treatment. The combination of JQ1 and the histone deacetylase inhibitor romidepsin further enhanced the apoptotic effect in vitro and in vivo. Thus, we propose that JQ1 alone, or in combination with romidepsin may serve as a novel therapeutic option for GCCs.
Project description:Pathologic activation of c-Myc plays a central role in pathogenesis of several neoplasias, including multiple myeloma. However, therapeutic targeting of c-Myc has remained elusive due to its lack of a clear ligand-binding domain. We therefore targeted c-Myc transcriptional function by another means, namely the disruption of chromatin-dependent signal transduction. Members of the bromodomain and extra-terminal (BET) subfamily of human bromodomain proteins (BRD2, BRD3 and BRD4) associate with acetylated chromatin and facilitate transcriptional activation by increasing the effective molarity of recruited transcriptional activators. Notably, BRD4 marks select M/G1 genes in mitotic chromatin for transcriptional memory and direct post-mitotic transcription, via direct interaction with the positive transcription elongation factor complex b (P-TEFb). Because c-Myc is known to regulate promoter-proximal pause release of Pol II, also through the recruitment of P-TEFb, we evaluated the selective small-molecule inhibitor of BET bromodomains, JQ1, as a chemical probe to interrogate the role of BET bromodomains in Myc-dependent transcription and to explore their role as therapeutic targets in c-Myc-driven neoplasias. Duplicate cultures of MM.1S, OPM1 and KMS11 human myeloma cells were treated with either DMSO alone or with JQ1 (500 nM), for 24 hours. Total RNA was extracted and hybridized to Affymetrix human Gene 1.0 ST microarrays (two arrays per treatment per cell line for a total of 12 arrays).
Project description:Epigenetic pathways regulate gene expression by controlling and interpreting chromatin modifications. Cancer cells are characterized by altered epigenetic landscapes and commonly exploit the chromatin regulatory machinery to enforce oncogenic gene expression programs. While chromatin alterations are, in principle, reversible and often amendable to drug intervention, the promise of targeting such pathways therapeutically has been hampered by our limited understanding of cancer-specific epigenetic dependencies. Here we describe a non-biased approach to probe epigenetic vulnerabilities in acute myeloid leukemia (AML) – an aggressive hematopoietic malignancy often associated with aberrant chromatin states. By screening a custom shRNA library targeting known chromatin regulators in a genetically defined AML mouse model, we identify the bromodomain-containing protein Brd4 as a critical requirement for disease maintenance. Suppression of Brd4 using shRNAs or the small-molecule inhibitor JQ1 led to robust anti-leukemic effects in vitro and in vivo, accompanied by terminal myeloid differentiation. Extensive evaluation of JQ1-sensitivity in primary human leukemia samples and in established cell lines revealed a broad activity of this compound against diverse AML subtypes. These effects are, at least in part, due to a requirement for Brd4 in maintaining Myc expression and promoting aberrant self-renewal. Together, our results indicate that Brd4 is a promising therapeutic target in AML and identify a small molecule that efficiently targets Myc. These findings also highlight the utility of RNAi screening as a discovery platform for revealing epigenetic vulnerabilities for direct pharmacologic intervention in cancer. In order to understand downstream targets of Brd4, we performed array in murine or human MLL-AF9/NrasG12D cell line under the condition that Brd4 was suppressed by using shRNAs or the small molecule inhibitor JQ1. To test the hypothesis that Myc might be an important target of Brd4, we performed arrary on murine ectopic Myc overexpression MLL-AF9/NrasG12D cell under JQ1 treatment.