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Kotekar A, Singh AK, Devaiah BN. BRD4 and MYC: power couple in transcription and disease. FEBS J 2023; 290:4820-4842. [PMID: 35866356 PMCID: PMC9867786 DOI: 10.1111/febs.16580] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/16/2022] [Accepted: 07/20/2022] [Indexed: 01/26/2023]
Abstract
The MYC proto-oncogene and BRD4, a BET family protein, are two cardinal proteins that have a broad influence in cell biology and disease. Both proteins are expressed ubiquitously in mammalian cells and play central roles in controlling growth, development, stress responses and metabolic function. As chromatin and transcriptional regulators, they play a critical role in regulating the expression of a burgeoning array of genes, maintaining chromatin architecture and genome stability. Consequently, impairment of their function or regulation leads to many diseases, with cancer being the most predominant. Interestingly, accumulating evidence indicates that regulation of the expression and functions of MYC are tightly intertwined with BRD4 at both transcriptional and post-transcriptional levels. Here, we review the mechanisms by which MYC and BRD4 are regulated, their functions in governing various molecular mechanisms and the consequences of their dysregulation that lead to disease. We present a perspective of how the regulatory mechanisms for the two proteins could be entwined at multiple points in a BRD4-MYC nexus that leads to the modulation of their functions and disease upon dysregulation.
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Affiliation(s)
- Aparna Kotekar
- Experimental Immunology Branch, NCI, NIH, Bethesda, MD 20892, USA
| | - Amit Kumar Singh
- Experimental Immunology Branch, NCI, NIH, Bethesda, MD 20892, USA
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2
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Wu T, Hou H, Dey A, Bachu M, Chen X, Wisniewski J, Kudoh F, Chen C, Chauhan S, Xiao H, Pan R, Ozato K. BRD4 directs mitotic cell division by inhibiting DNA damage. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.02.547436. [PMID: 37546888 PMCID: PMC10401944 DOI: 10.1101/2023.07.02.547436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
BRD4 binds to acetylated histones to regulate transcription and drive cancer cell proliferation. However, the role of BRD4 in normal cell growth remains to be elucidated. Here we investigated the question by using mouse embryonic fibroblasts with conditional Brd4 knockout (KO). We found that Brd4KO cells grow more slowly than wild type cells: they do not complete replication, fail to achieve mitosis, and exhibit extensive DNA damage throughout all cell cycle stages. BRD4 was required for expression of more than 450 cell cycle genes including genes encoding core histones and centromere/kinetochore proteins that are critical for genome replication and chromosomal segregation. Moreover, we show that many genes controlling R-loop formation and DNA damage response (DDR) require BRD4 for expression. Finally, BRD4 constitutively occupied genes controlling R-loop, DDR and cell cycle progression. We suggest that BRD4 epigenetically marks those genes and serves as a master regulator of normal cell growth.
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3
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Liu Q, Chung S, Murata MM, Han B, Gao B, Zhang M, Lee TY, Chirshev E, Unternaehrer J, Tanaka H, Giuliano AE, Cui Y, Cui X. TOP1 inhibition induces bifurcated JNK/MYC signaling that dictates cancer cell sensitivity. Int J Biol Sci 2022; 18:4203-4218. [PMID: 35844787 PMCID: PMC9274500 DOI: 10.7150/ijbs.70583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 06/14/2022] [Indexed: 02/05/2023] Open
Abstract
Rationale: Triple-negative breast cancer (TNBC) does not respond to anti-estrogen and anti-HER2 therapies and is commonly treated by chemotherapy. TNBC has a high recurrence rate, particularly within the first 3 years. Thus, there is an urgent clinical need to develop more effective therapies for TNBC. Topoisomerase I (TOP1) inhibitors cause DNA damage, making these drugs desirable for TNBC treatment since DNA repair machinery is defective in this subtype of breast cancer. Among the main molecular subtypes of breast cancer, the TNBC cell lines exhibited the highest TOP1 inhibition sensitivity. However, clinically used TOP1 inhibitors, such as topotecan and irinotecan, have shown limited clinical applications and the reasons remain unclear. Understanding the mechanism of differential responses to TOP1 blockade and identifying the predictive markers for cancer cell sensitivity will help further TOP1-targeted therapy for TNBC treatment and improve the clinical use of TOP1 inhibitors. Methods: Viability assays were used to evaluate breast cancer cell sensitivity to topotecan and other TOP1 inhibitors as well as TOP2 inhibitors. An in vitro-derived topotecan-resistant TNBC cell model and TNBC xenograft models were employed to confirm cancer cell response to TOP1 blockade. RNA-seq was used to identify potential predictive markers for TNBC cell response to TOP1 blockade. Western blotting and qRT-PCR were performed to measure the protein levels and RNA expression. ATAC-seq and luciferase reporter assays were used to examine MYC transcriptional regulations. The effects of MYC and JNK in cancer cell response to TOP1 inhibition were validated via loss-of-function and gain-of-function experiments. Results: We observed two distinct and diverging cancer cell responses - sensitive versus resistant to TOP1 inhibition, which was confirmed by TNBC xenograft mouse models treated by topotecan. TNBC cells exhibited bifurcated temporal patterns of ATR pathway activation upon TOP1 inhibitor treatment. The sensitive TNBC cells showed an "up then down" dynamic pattern of ATR/Chk1 signaling, while the resistant TNBC cells exhibited a "persistently up" profile. On the contrary, opposite temporal patterns of induced expression of MYC, a key regulator and effector of DNA damage, were found in TNBC cells treated by TOP1 inhibitors. Mechanistically, we showed that TOP1-induced JNK signaling upregulated MYC expression. Furthermore, pharmacological inhibition of ATR reversed TNBC cell resistance to topotecan, whereas MYC knockdown and JNK inhibition reduced cancer cell sensitivity. Conclusions: Dynamic temporal profiles of induced ATR/Chk1 and JNK activation as well as MYC expression, may predict cancer cell response to TOP1 inhibitors. JNK activation-mediated constitutive elevation of MYC expression may represent a novel mechanism governing cancer cell sensitivity to TOP1-targeting therapy. Our results may provide implications for identifying TNBC patients who might benefit from the treatment with TOP1 inhibitors.
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Affiliation(s)
- Qizhi Liu
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Stacey Chung
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Michael M. Murata
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Bingchen Han
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Bowen Gao
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Maoqi Zhang
- Key Laboratory for Breast Cancer Diagnosis and Treatment, Shantou University Medical College Cancer Hospital, Shantou 515041, China
| | - Tian-Yu Lee
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Evgeny Chirshev
- Loma Linda University, Department of Basic Sciences, 11085 Campus Street Mortensen Hall 219, Loma Linda, CA 92354, USA
| | - Juli Unternaehrer
- Loma Linda University, Department of Basic Sciences, 11085 Campus Street Mortensen Hall 219, Loma Linda, CA 92354, USA
| | - Hisashi Tanaka
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Armando E. Giuliano
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Yukun Cui
- Key Laboratory for Breast Cancer Diagnosis and Treatment, Shantou University Medical College Cancer Hospital, Shantou 515041, China
| | - Xiaojiang Cui
- Department of Surgery, Samuel Oschin Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
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Song Y, Hu G, Jia J, Yao M, Wang X, Lu W, Hutchins AP, Chen J, Ozato K, Yao H. DNA Damage Induces Dynamic Associations of BRD4/P-TEFb With Chromatin and Modulates Gene Transcription in a BRD4-Dependent and -Independent Manner. Front Mol Biosci 2020; 7:618088. [PMID: 33344510 PMCID: PMC7746802 DOI: 10.3389/fmolb.2020.618088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 10/29/2020] [Indexed: 12/12/2022] Open
Abstract
The bromodomain-containing protein BRD4 has been thought to transmit epigenetic information across cell divisions by binding to both mitotic chromosomes and interphase chromatin. UV-released BRD4 mediates the recruitment of active P-TEFb to the promoter, which enhances transcriptional elongation. However, the dynamic associations between BRD4 and P-TEFb and BRD4-mediated gene regulation after UV stress are largely unknown. In this study, we found that BRD4 dissociates from chromatin within 30 min after UV treatment and thereafter recruits chromatin. However, P-TEFb binds tightly to chromatin right after UV treatment, suggesting that no interactions occur between BRD4 and P-TEFb within 30 min after UV stress. BRD4 knockdown changes the distribution of P-TEFb among nuclear soluble and chromatin and downregulates the elongation activity of RNA polymerase II. Inhibition of JNK kinase but not other MAP kinases impedes the interactions between BRD4 and P-TEFb. RNA-seq and ChIP assays indicate that BRD4 both positively and negatively regulates gene transcription in cells treated with UV stress. These results reveal previously unrecognized dynamics of BRD4 and P-TEFb after UV stress and regulation of gene transcription by BRD4 acting as either activator or repressor in a context-dependent manner.
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Affiliation(s)
- Yawei Song
- School of Life Sciences, University of Science and Technology of China, Hefei, China.,CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China.,Bioland Laboratory (Guangzhou Regenerative Medicine and Health GuangDong Laboratory), Guangzhou, China.,Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Gongcheng Hu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China.,Bioland Laboratory (Guangzhou Regenerative Medicine and Health GuangDong Laboratory), Guangzhou, China.,Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Jinping Jia
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China
| | - Mingze Yao
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China
| | - Xiaoshan Wang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China
| | - Wenliang Lu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China
| | - Andrew P Hutchins
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Jiekai Chen
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China.,Bioland Laboratory (Guangzhou Regenerative Medicine and Health GuangDong Laboratory), Guangzhou, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Keiko Ozato
- Division of Developmental Biology, National Institute of Child Health and Human Development, Bethesda, MD, United States
| | - Hongjie Yao
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, China.,Bioland Laboratory (Guangzhou Regenerative Medicine and Health GuangDong Laboratory), Guangzhou, China.,Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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5
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Liu PY, Sokolowski N, Guo ST, Siddiqi F, Atmadibrata B, Telfer TJ, Sun Y, Zhang L, Yu D, Mccarroll J, Liu B, Yang RH, Guo XY, Tee AE, Itoh K, Wang J, Kavallaris M, Haber M, Norris MD, Cheung BB, Byrne JA, Ziegler DS, Marshall GM, Dinger ME, Codd R, Zhang XD, Liu T. The BET bromodomain inhibitor exerts the most potent synergistic anticancer effects with quinone-containing compounds and anti-microtubule drugs. Oncotarget 2018; 7:79217-79232. [PMID: 27764794 PMCID: PMC5346709 DOI: 10.18632/oncotarget.12640] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/28/2016] [Indexed: 11/25/2022] Open
Abstract
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. Treatment with JQ1 blocked the recruitment of Nrf2 to the antioxidant responsive elements at Nrf2 target gene promoters, and JQ1 exerted synergistic anticancer effects with nanaomycin by blocking the Nrf2-antioxidant signaling pathway. JQ1 and vincristine synergistically induced neuroblastoma cell cycle arrest at the G2/M phase, aberrant mitotic spindle assembly formation and apoptosis, but showed no effect on cell survival in normal non-malignant cells. Importantly, co-treatment with JQ1 and vincristine synergistically suppressed tumor progression in neuroblastoma-bearing mice. These results strongly suggest that patients treated with BET bromodomain inhibitors in clinical trials should be co-treated with vincristine.
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Affiliation(s)
- Pei Y Liu
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Nicholas Sokolowski
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Su T Guo
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Faraz Siddiqi
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Bernard Atmadibrata
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Thomas J Telfer
- School of Medical Sciences (Pharmacology) and Bosch Institute, The University of Sydney, Sydney, Australia
| | - Yuting Sun
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Lihong Zhang
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia.,Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Denise Yu
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Joshua Mccarroll
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Bing Liu
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Rui H Yang
- Department of Molecular Biology, Shanxi Cancer Hospital and Institute, Affiliated Hospital of Shanxi Medical University, Shanxi, China
| | - Xiang Y Guo
- Department of Molecular Biology, Shanxi Cancer Hospital and Institute, Affiliated Hospital of Shanxi Medical University, Shanxi, China
| | - Andrew E Tee
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Ken Itoh
- Department of Stress Response Science, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Jenny Wang
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia.,Centre for Childhood Cancer Research, University of New South Wales Medicine, University of New South Wales Australia, Sydney, Australia
| | - Maria Kavallaris
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Michelle Haber
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Murray D Norris
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia.,Centre for Childhood Cancer Research, University of New South Wales Medicine, University of New South Wales Australia, Sydney, Australia
| | - Belamy B Cheung
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia
| | - Jennifer A Byrne
- Children's Cancer Research Unit, Kids Research Institute, The Children's Hospital at Westmead, Westmead, Australia
| | - David S Ziegler
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia.,Kids Cancer Centre, Sydney Children's Hospital, High Street, Randwick, Australia
| | - Glenn M Marshall
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia.,Kids Cancer Centre, Sydney Children's Hospital, High Street, Randwick, Australia
| | - Marcel E Dinger
- Garvan Institute of Medical Research, Darlinghurst, Australia.,St Vincent's Clinical School, University of New South Wales Medicine, University of New South Wales Australia, Darlinghurst, Australia
| | - Rachel Codd
- School of Medical Sciences (Pharmacology) and Bosch Institute, The University of Sydney, Sydney, Australia
| | - Xu D Zhang
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Department of Molecular Biology, Shanxi Cancer Hospital and Institute, Affiliated Hospital of Shanxi Medical University, Shanxi, China
| | - Tao Liu
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, Australia.,Centre for Childhood Cancer Research, University of New South Wales Medicine, University of New South Wales Australia, Sydney, Australia
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Festuccia N, Gonzalez I, Owens N, Navarro P. Mitotic bookmarking in development and stem cells. Development 2017; 144:3633-3645. [DOI: 10.1242/dev.146522] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The changes imposed on the nucleus, chromatin and its regulators during mitosis lead to the dismantlement of most gene regulatory processes. However, an increasing number of transcriptional regulators are being identified as capable of binding their genomic targets during mitosis. These so-called ‘mitotic bookmarking factors’ encompass transcription factors and chromatin modifiers that are believed to convey gene regulatory information from mother to daughter cells. In this Primer, we review mitotic bookmarking processes in development and stem cells and discuss the interest and potential importance of this concept with regard to epigenetic regulation and cell fate transitions involving cellular proliferation.
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Affiliation(s)
- Nicola Festuccia
- Epigenetics of Stem Cells, Department of Developmental and Stem Cell Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France
| | - Inma Gonzalez
- Epigenetics of Stem Cells, Department of Developmental and Stem Cell Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France
| | - Nick Owens
- Epigenetics of Stem Cells, Department of Developmental and Stem Cell Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France
| | - Pablo Navarro
- Epigenetics of Stem Cells, Department of Developmental and Stem Cell Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France
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Comparative drug screening in NUT midline carcinoma. Br J Cancer 2014; 110:1189-98. [PMID: 24518598 PMCID: PMC3950881 DOI: 10.1038/bjc.2014.54] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 12/04/2013] [Accepted: 01/09/2014] [Indexed: 12/14/2022] Open
Abstract
Background: The NUT midline carcinoma (NMC) is a rare but fatal cancer for which systematic testing of therapy options has never been performed. Methods: On the basis of disease biology, we compared the efficacy of the CDK9 inhibitor flavopiridol (FP) with a panel of anticancer agents in NMC cell lines and mouse xenografts. Results: In vitro anthracyclines, topoisomerase inhibitors, and microtubule poisons were among the most cytotoxic drug classes for NMC cells, while efficacy of the bromodomain inhibitor JQ1 varied considerably between lines carrying different BRD4 (bromodomain-containing protein 4)–NUT (nuclear protein in testis) translocations. Efficacy of FP was comparable to vincristine and doxorubicin, drugs that have been previously used in NMC patients. All three compounds showed significantly better activity than etoposide and vorinostat, agents that have also been used in NMC patients. Statins and antimetabolites demonstrated intermediate single-agent efficacy. In vivo, vincristine significantly inhibited tumour growth in two different NMC xenografts. Flavopiridol in vivo was significantly effective in one of the two NMC xenograft lines, demonstrating the biological heterogeneity of this disease. Conclusions: These results demonstrate that FP may be of benefit to a subset of patients with NMC, and warrant a continued emphasis on microtubule inhibitors, anthracyclines, and topoisomerase inhibitors as effective drug classes in this disease.
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Devaiah BN, Singer DS. Two faces of brd4: mitotic bookmark and transcriptional lynchpin. Transcription 2012; 4:13-7. [PMID: 23131666 DOI: 10.4161/trns.22542] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The bromodomain protein BRD4 links cell cycle and transcription, bookmarking active genes during mitosis and serving as a scaffold for transcription factors. Our recent discovery that BRD4 is a RNA Polymerase II CTD kinase identifies a novel transcriptional function. Here we discuss our model in the context of current knowledge.
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