Read by QxMD icon Read


Dimitrios Spiliotopoulos, Amedeo Caflisch
We review the results of fragment-based high-throughput docking to the N-terminal bromodomain of BRD4 and the CREBBP bromodomain. In both docking campaigns the ALTA (anchor-based library tailoring) procedure was used to reduce the size of the initial library by selecting for flexible docking only the molecules that contain a fragment with favorable predicted binding energy. Ranking by a force field-based energy with solvation has resulted in small-molecule hits with low-micromolar affinity and favorable ligand efficiency...
March 2016: Drug Discovery Today. Technologies
Guillaume Andrieu, Anna C Belkina, Gerald V Denis
Several cancer clinical trials for small molecule inhibitors of BET bromodomain proteins have been initiated. There is enthusiasm for the anti-proliferative effect of inhibiting BRD4, one of the targets of these inhibitors, which is thought to cooperate with MYC, a long-desired target for cancer therapeutics. However, no current inhibitor is selective for BRD4 among the three somatic BET proteins, which include BRD2 and BRD3; their respective functions are partially overlapping and none are functionally redundant with BRD4...
March 2016: Drug Discovery Today. Technologies
Aaron J Stonestrom, Sarah C Hsu, Michael T Werner, Gerd A Blobel
Pharmacologic inhibitors of the bromodomain and extra-terminal motif (BET) protein family are in clinical trials for the treatment of hematologic malignancies, yet the functions of individual BET proteins remain largely uncharacterized. We review the molecular roles of BETs in the context of erythropoiesis. Studies in this lineage have provided valuable insights into their mechanisms of action, and helped define the individual and overlapping functions of BET protein family members BRD2, BRD3, and BRD4. These studies have important ramifications for our understanding of the molecular and physiologic roles of BET proteins, and provide a framework for elucidating some of the beneficial and adverse effects of pharmacologic inhibitors...
March 2016: Drug Discovery Today. Technologies
Cheng-Ming Chiang
BRD4 is an epigenetic regulator and transcription cofactor whose phosphorylation by CK2 and dephosphorylation by PP2A modulates its function in chromatin targeting, factor recruitment, and cancer progression. While the bromodomains of BET family proteins, including BRD4, BRD2, BRD3 and BRDT, have been the primary targets of small compounds such as JQ1, I-BET and MS417 that show promising anticancer effects against some hematopoietic cancer and solid tumors, drug resistance upon prolonged treatment necessitates a better understanding of alternative pathways underlying not only the resistance but also persistent BET protein dependence for identifying new targets and effective combination therapy strategies...
March 2016: Drug Discovery Today. Technologies
Kathrin Fielitz, Kristina Althoff, Katleen De Preter, Julie Nonnekens, Jasmin Ohli, Sandra Elges, Wolfgang Hartmann, Günter Klöppel, Thomas Knösel, Marc Schulte, Ludger Klein-Hitpass, Daniela Beisser, Henning Reis, Annette Eyking, Elke Cario, Johannes H Schulte, Alexander Schramm, Ulrich Schüller
Amplification or overexpression of MYCN is involved in development and maintenance of multiple malignancies. A subset of these tumors originates from neural precursors, including the most aggressive forms of the childhood tumors, neuroblastoma and medulloblastoma. In order to model the spectrum of MYCN-driven neoplasms in mice, we transgenically overexpressed MYCN under the control of the human GFAP-promoter that, among other targets, drives expression in neural progenitor cells. However, LSL-MYCN;hGFAP-Cre double transgenic mice did neither develop neural crest tumors nor tumors of the central nervous system, but presented with neuroendocrine tumors of the pancreas and, less frequently, the pituitary gland...
October 19, 2016: Oncotarget
Pei Y Liu, Nicholas Sokolowski, Su T Guo, Faraz Siddiqi, Bernard Atmadibrata, Thomas J Telfer, Yuting Sun, Lihong Zhang, Denise Yu, Joshua Mccarroll, Bing Liu, Rui H Yang, Xiang Y Guo, Andrew E Tee, Ken Itoh, Jenny Wang, Maria Kavallaris, Michelle Haber, Murray D Norris, Belamy B Cheung, Jennifer A Byrne, David S Ziegler, Glenn M Marshall, Marcel E Dinger, Rachel Codd, Xu D Zhang, Tao Liu
BET bromodomain inhibitors are very promising novel anticancer agents, however, single therapy does not cause tumor regression in mice, suggesting the need for combination therapy. After screening a library of 2697 small molecule compounds, we found that two classes of compounds, the quinone-containing compounds such as nanaomycin and anti-microtubule drugs such as vincristine, exerted the best synergistic anticancer effects with the BET bromodomain inhibitor JQ1 in neuroblastoma cells. Mechanistically, the quinone-containing compound nanaomycin induced neuroblastoma cell death but also activated the Nrf2-antioxidant signaling pathway, and the BET bromodomain proteins BRD3 and BRD4 formed a protein complex with Nrf2...
October 13, 2016: Oncotarget
Tong Zhou, Luke Erber, Bing Liu, Yankun Gao, Hai-Bin Ruan, Yue Chen
Proline hydroxylation is a critical cellular mechanism regulating oxygen-response pathways in tumor initiation and progression. Yet, its substrate diversity and functions remain largely unknown. Here, we report a system-wide analysis to characterize proline hydroxylation substrates in cancer cells using an immunoaffinity-purification assisted proteomics strategy. We identified 562 sites from 272 proteins in HeLa cells. Bioinformatic analysis revealed that proline hydroxylation substrates are significantly enriched with mRNA processing and stress-response cellular pathways with canonical and diverse flanking sequence motifs...
October 13, 2016: Oncotarget
Ke Ren, Wei Zhang, Xiaoqing Chen, Yingyu Ma, Yue Dai, Yimei Fan, Yayi Hou, Ren Xiang Tan, Erguang Li
The human HSV-1 and -2 are common pathogens of human diseases. Both host and viral factors are involved in HSV lytic infection, although detailed mechanisms remain elusive. By screening a chemical library of epigenetic regulation, we identified bromodomain-containing protein 4 (BRD4) as a critical player in HSV infection. We show that treatment with pan BD domain inhibitor enhanced both HSV infection. Using JQ1 as a probe, we found that JQ1, a defined BD1 inhibitor, acts through BRD4 protein since knockdown of BRD4 expression ablated JQ1 effect on HSV infection...
October 2016: PLoS Pathogens
Min Huang, Jacqueline S Garcia, Daniel Thomas, Li Zhu, Le Xuan Truong Nguyen, Steven M Chan, Ravindra Majeti, Bruno C Medeiros, Beverly S Mitchell
The mechanisms underlying activation of the BET pathway in AML cells remain poorly understood. We have discovered that autophagy is activated in acute leukemia cells expressing mutant nucleophosmin 1 (NPMc+) or MLL-fusion proteins. Autophagy activation results in the degradation of NPM1 and HEXIM1, two negative regulators of BET pathway activation. Inhibition of autophagy with pharmacologic inhibitors or through knocking down autophagy-related gene 5 (Atg5) expression increases the expression of both NPM1 and HEXIM1...
October 6, 2016: Oncotarget
Chongxiang Xiong, Monica V Masucci, Xiaoxu Zhou, Na Liu, Xiujuan Zang, Evelyn Tolbert, Ting C Zhao, Shougang Zhuang
Bromodomain and extra-terminal (BET) protein inhibitors have been shown to effectively inhibit tumorgenesis and ameliorate pulmonary fibrosis by targeting bromodomain proteins that bind acetylated chromatin markers. However, their pharmacological effects in renal fibrosis remain unclear. In this study, we examined the effect of I-BET151, a selective and potent BET inhibitor, on renal fibroblast activation and renal fibrosis. In cultured renal interstitial fibroblasts, exposure of cells to I-BET151, or silencing of bromodoma in-containing protein 4 (Brd4), a key BET protein isoform, significantly reduced their activation as indicated by decreased expression of α-smooth muscle actin, collagen 1 and fibronectin...
October 6, 2016: Oncotarget
Michael P Murphy
In this issue of Molecular Cell, Barrow et al. (2016) use two complementary approaches-one an assessment of a chemical library, and the other a genome-wide CRISPR screen-that both identify bromodomain-containing protein 4 (Brd4) as a therapeutic target for mtDNA diseases affecting complex I.
October 6, 2016: Molecular Cell
Emily J Faivre, Denise Wilcox, Xiaoyu Lin, Paul Hessler, Maricel Torrent, Wei He, Tamar Uziel, Daniel H Albert, Keith McDaniel, Warren Kati, Yu Shen
: Competitive inhibitors of acetyl-lysine binding to the bromodomains of the BET (bromodomain and extra terminal) family are being developed for the treatment of solid and hematologic malignancies. The function of BET family member BRD4 at enhancers/super-enhancers has been shown to sustain signal-dependent or pathogenic gene expression programs. Here the hypothesis was tested that the transcription factor drivers of castration-resistant prostate cancer (CRPC) clinical progression, including the Androgen Receptor (AR), are critically dependent on BRD4 and thus represent a sensitive solid tumor indication for the BET inhibitor ABBV-075...
October 5, 2016: Molecular Cancer Research: MCR
Barry M Zee, Amy B Dibona, Artyom A Alekseyenko, Christopher A French, Mitzi I Kuroda
Defects in chromatin proteins frequently manifest in diseases. A striking case of a chromatin-centric disease is NUT-midline carcinoma (NMC), which is characterized by expression of NUT as a fusion partner most frequently with BRD4. ChIP-sequencing studies from NMC patients revealed that BRD4-NUT (B4N) covers large genomic regions and elevates transcription within these domains. To investigate how B4N modulates chromatin, we performed affinity purification of B4N when ectopically expressed in 293-TREx cells and quantified the associated histone posttranslational modifications (PTM) using proteomics...
2016: PloS One
Terry D Crawford, F Anthony Romero, Kwong Wah Lai, Vickie Tsui, Alexander M Taylor, Gladys de Leon Boenig, Cameron L Noland, Jeremy Murray, Justin Ly, Edna F Choo, Thomas L Hunsaker, Emily W Chan, Mark Merchant, Samir Kharbanda, Karen E Gascoigne, Susan Kaufman, Maureen H Beresini, Jiangpeng Liao, Wenfeng Liu, Kevin X Chen, Zhongguo Chen, Andrew R Conery, Alexandre Côté, Hariharan Jayaram, Ying Jiang, James R Kiefer, Tracy Kleinheinz, Yingjie Li, Jonathan Maher, Eneida Pardo, Florence Poy, Kerry L Spillane, Fei Wang, Jian Wang, Xiaocang Wei, Zhaowu Xu, Zhongya Xu, Ivana Yen, Laura Zawadzke, Xiaoyu Zhu, Steven Bellon, Richard Cummings, Andrea G Cochran, Brian K Albrecht, Steven Magnuson
The single bromodomain of the closely related transcriptional regulators CBP/EP300 is a target of much recent interest in cancer and immune system regulation. A co-crystal structure of a ligand-efficient screening hit and the CBP bromodomain guided initial design targeting the LPF shelf, ZA loop, and acetylated lysine binding regions. Structure-activity relationship studies allowed us to identify a more potent analogue. Optimization of permeability and microsomal stability and subsequent improvement of mouse hepatocyte stability afforded 59 (GNE-272, TR-FRET IC50 = 0...
September 28, 2016: Journal of Medicinal Chemistry
Marc Baud'huin, François Lamoureux, Camille Jacques, Lidia Rodriguez Calleja, Thibaut Quillard, Céline Charrier, Jérome Amiaud, Martine Berreur, Bénédicte Brounais-LeRoyer, Robert Owen, Gwendolen C Reilly, James E Bradner, Dominique Heymann, Benjamin Ory
Histone modifications are important for maintaining the transcription program. BET proteins, an important class of "histone reading proteins", have recently been described as essential in bone biology. This study presents the therapeutic opportunity of BET protein inhibition in osteoporosis. We find that the pharmacological BET protein inhibitor JQ1 rescues pathologic bone loss in a post-ovariectomy osteoporosis model by increasing the trabecular bone volume and restoring mechanical properties. The BET protein inhibition suppresses osteoclast differentiation and activity as well as the osteoblastogenesis in vitro...
September 23, 2016: Bone
Joeva J Barrow, Eduardo Balsa, Francisco Verdeguer, Clint D J Tavares, Meghan S Soustek, Louis R Hollingsworth, Mark Jedrychowski, Rutger Vogel, Joao A Paulo, Jan Smeitink, Steve P Gygi, John Doench, David E Root, Pere Puigserver
Mitochondrial diseases comprise a heterogeneous group of genetically inherited disorders that cause failures in energetic and metabolic function. Boosting residual oxidative phosphorylation (OXPHOS) activity can partially correct these failures. Herein, using a high-throughput chemical screen, we identified the bromodomain inhibitor I-BET 525762A as one of the top hits that increases COX5a protein levels in complex I (CI) mutant cybrid cells. In parallel, bromodomain-containing protein 4 (BRD4), a target of I-BET 525762A, was identified using a genome-wide CRISPR screen to search for genes whose loss of function rescues death of CI-impaired cybrids grown under conditions requiring OXPHOS activity for survival...
October 6, 2016: Molecular Cell
Zeynab Najafova, Roberto Tirado-Magallanes, Malayannan Subramaniam, Tareq Hossan, Geske Schmidt, Sankari Nagarajan, Simon J Baumgart, Vivek Kumar Mishra, Upasana Bedi, Eric Hesse, Stefan Knapp, John R Hawse, Steven A Johnsen
Proper temporal epigenetic regulation of gene expression is essential for cell fate determination and tissue development. The Bromodomain-containing Protein-4 (BRD4) was previously shown to control the transcription of defined subsets of genes in various cell systems. In this study we examined the role of BRD4 in promoting lineage-specific gene expression and show that BRD4 is essential for osteoblast differentiation. Genome-wide analyses demonstrate that BRD4 is recruited to the transcriptional start site of differentiation-induced genes...
September 19, 2016: Nucleic Acids Research
Guillaume Andrieu, Anna H Tran, Katherine J Strissel, Gerald V Denis
The Bromodomain and ExtraTerminal (BET) proteins are epigenetic 'readers' of acetylated histones in chromatin and have been identified as promising therapeutic targets in diverse cancers. However, it remains unclear how individual family members participate in cancer progression, and small molecule inhibitors such as JQ1 can target functionally independent BET proteins. Here we report a signaling pathway involving BRD4 and the ligand/receptor pair Jagged1/Notch1 that sustains triple-negative breast cancer migration and invasion...
September 20, 2016: Cancer Research
Jennifer M Sahni, Sylvia S Gayle, Kristen L Weber-Bonk, Leslie Cuellar Vite, Jennifer L Yori, Bryan Webb, Erika K Ramos, Darcie D Seachrist, Melissa D Landis, Jenny C Chang, James E Bradner, Ruth A Keri
Bromodomain and extraterminal (BET) proteins are epigenetic "readers" that recognize acetylated histones and mark areas of the genome for transcription. BRD4, a BET family member protein, has been implicated in a number of types of cancer, and BET protein inhibitors (BETi) are efficacious in many preclinical cancer models. However, the drivers of response to BETi vary depending on tumor type, and little is known regarding the target genes conveying BETi activity in triple-negative breast cancer (TNBC). Here, we show that BETi repress growth of multiple in vitro and in vivo models of TNBC by inducing two terminal responses: apoptosis and senescence...
September 20, 2016: Journal of Biological Chemistry
Andrew K Urick, Luis Pablo Calle, Juan F Espinosa, Haitao Hu, William C K Pomerantz
To evaluate its potential as a ligand discovery tool, we compare a newly developed 1D protein-observed fluorine NMR (PrOF NMR) screening method with the well-characterized ligand-observed (1)H CPMG NMR screen. We selected the first bromodomain of Brd4 as a model system to benchmark PrOF NMR because of the high ligandability of Brd4 and the need for small molecule inhibitors of related epigenetic regulatory proteins. We compare the two methods' hit sensitivity, triaging ability, experiment speed, material consumption, and the potential for false positives and negatives...
October 5, 2016: ACS Chemical Biology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"