1
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Lyu Y, Guan X, Xu X, Wang P, Li Q, Panigrahi M, Zhang J, Chen N, Huang B, Lei C. A whole genome scan reveals distinct features of selection in Zhaotong cattle of Yunnan province. Anim Genet 2023; 54:731-742. [PMID: 37796667 DOI: 10.1111/age.13363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 08/09/2023] [Accepted: 08/09/2023] [Indexed: 10/07/2023]
Abstract
Over the years, indigenous cattle have not only played an essential role in securing primary food sources but have also been utilized for labor by humans, making them invaluable genetic resources. The Zhaotong cattle, a native Chinese breed from the Yunnan province, possess excellent meat quality and resistance to heat and humidity. Here we used whole genome sequencing data of 104 animals to delve into the population structure, genomic diversity and potential positive selection signals in Zhaotong cattle. The findings of this study demonstrate that the genetic composition of Zhaotong cattle was primarily derived from Chinese indicine cattle and East Asian cattle. The nucleotide diversity of Zhaotong cattle was only lower than that of Chinese indicine cattle, which was much higher than that of other taurine cattle. Genome-wide selection scans detected a series of positive candidate regions containing multiple key genes related to bone development and metabolism (CA10, GABRG3, GLDN and NOTUM), meat quality traits (ALG8, LINGO2, MYO5B, PRKG1 and GABRB1), immune response (ADA2, BMF, LEF1 and PAK6) and heat resistance (EIF2AK4 and LEF1). In summary, this study supplies essential genetic insights into the genome diversity within Zhaotong cattle and provides a foundational framework for comprehending the genetic basis of indigenous cattle breeds.
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Affiliation(s)
- Yang Lyu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Xiwen Guan
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Xinglong Xu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Pengfei Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Qiaoxian Li
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Manjit Panigrahi
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, UP, India
| | - Jicai Zhang
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Ningbo Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Bizhi Huang
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Chuzhao Lei
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
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2
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Singh PK, Roukounakis A, Weber A, Das KK, Sohm B, Villunger A, Garcia-Saez AJ, Häcker G. Dynein light chain binding determines complex formation and posttranslational stability of the Bcl-2 family members Bmf and Bim. Cell Death Differ 2019; 27:434-450. [PMID: 31189926 DOI: 10.1038/s41418-019-0365-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/17/2019] [Accepted: 05/23/2019] [Indexed: 12/31/2022] Open
Abstract
The BH3-only class of Bcl-2 family proteins triggers mitochondrial apoptosis. Several mechanisms are used to restrain the pro-apoptotic activity of these proteins. Dynein light chain (DYNLL) 1 and 2 has been proposed to negatively regulate the activity of Bim and Bmf, respectively, and the Bim-DYNLL1 interaction leads to the formation of large protein complexes on mitochondria. Here we found that Bim and Bmf interact with both isoforms of DYNLL (DYNLL1 and DYNLL2). DYNLL1/2 not only induced homo-dimerization of Bim and Bmf but also led to the formation of ternary complexes (Bim-DYNLL-Bmf), both in cell-free and in cellular systems. DYNLL-induced oligomerization stabilized Bmf in cultured cells and inhibited its degradation by the ubiquitin-independent 20S proteasome in a cell-free system. Surprisingly, overexpression of wild-type Bmf but not of a DYNLL-binding-deficient mutant induced degradation of endogenous Bim in different cell lines, but both variants sensitized to apoptosis. Mutant Bmf incapable of interacting with anti-apoptotic Bcl-2 proteins and of inducing apoptosis still caused Bim degradation. These results suggest that Bmf overexpression-induced Bim degradation is not due to the displacement of Bim from anti-apoptotic Bcl-2 proteins but a direct consequence of the modulation of Bim-DYNLL association. A peptide derived from the DYNLL-binding domain of Bim also led to the degradation of Bim as well as of its preferred binding partner Mcl-1. Thus DYNLL regulates the mitochondrial pathway of apoptosis by determining the stability of Bmf, Bim, and Mcl-1 proteins.
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Affiliation(s)
- Prafull Kumar Singh
- Institute of Medical Microbiology and Hygiene, Faculty of Medicine, Medical Center - University of Freiburg, 79104, Freiburg, Germany
| | - Aristomenis Roukounakis
- Institute of Medical Microbiology and Hygiene, Faculty of Medicine, Medical Center - University of Freiburg, 79104, Freiburg, Germany
| | - Arnim Weber
- Institute of Medical Microbiology and Hygiene, Faculty of Medicine, Medical Center - University of Freiburg, 79104, Freiburg, Germany
| | - Kushal Kumar Das
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, 72076, Tübingen, Germany
| | - Benedicte Sohm
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, 6020, Innsbruck, Austria.,Laboratoire Interdisciplinaire des Environnements Continentaux UMR 7360 CNRS - Université de Lorraine, Metz, France
| | - Andreas Villunger
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, 6020, Innsbruck, Austria
| | - Ana J Garcia-Saez
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, 72076, Tübingen, Germany
| | - Georg Häcker
- Institute of Medical Microbiology and Hygiene, Faculty of Medicine, Medical Center - University of Freiburg, 79104, Freiburg, Germany. .,BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.
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3
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Ghosh A, Zhao S, Lo CS, Maachi H, Chenier I, Lateef MA, Abdo S, Filep JG, Ingelfinger JR, Zhang SL, Chan JSD. Heterogeneous Nuclear Ribonucleoprotein F Mediates Insulin Inhibition of Bcl2-Modifying Factor Expression and Tubulopathy in Diabetic Kidney. Sci Rep 2019; 9:6687. [PMID: 31040360 PMCID: PMC6491582 DOI: 10.1038/s41598-019-43218-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 02/04/2019] [Indexed: 11/25/2022] Open
Abstract
We investigated the molecular mechanism(s) by which insulin prevents Bcl2-modifying factor (Bmf)-induced renal proximal tubular cell (RPTC) apoptosis and loss in diabetic mice. Transgenic mice (Tg) mice specifically overexpressing human BMF in RPTCs and non-Tg littermates were studied at 10 to 20 weeks of age. Non-diabetic littermates, diabetic Akita mice +/− insulin implant, Akita Tg mice specifically overexpressing heterogeneous nuclear ribonucleoprotein F (hnRNP F) in their RPTCs and immortalized rat renal proximal tubular cells (IRPTCs) were also studied. BMF-Tg mice exhibited higher systolic blood pressure, urinary albumin/creatinine ratio, RPTC apoptosis and urinary RPTCs than non-Tg mice. Insulin treatment in Akita mice and Akita mice overexpressing hnRNP F suppressed Bmf expression and RPTC apoptosis. In hyperinsulinemic-euglycemic wild type mice, renal Bmf expression was down-regulated with up-regulation of hnRNP F. In vitro, insulin inhibited high glucose-stimulation of Bmf expression, predominantly via p44/42 mitogen-activated protein kinase (MAPK) signaling. Transfection of p44/42 MAPK or hnRNP F small interfering RNA (siRNA) prevented insulin inhibition of Bmf expression. HnRNP F inhibited Bmf transcription via hnRNP F-responsive element in the Bmf promoter. Our results demonstrate that hnRNP F suppression of Bmf transcription is an important mechanism by which insulin protects RPTCs from apoptosis in diabetes.
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Affiliation(s)
- Anindya Ghosh
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Shuiling Zhao
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Chao-Sheng Lo
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Hasna Maachi
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Isabelle Chenier
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Muhammad Abdul Lateef
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Shaaban Abdo
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada
| | - Janos G Filep
- Département de pathologie et biologie cellulaire, Université de Montréal, Centre de recherche, Hôpital Maisonneuve-Rosemont, 5415 boul. de l'Assomption, Montréal, QC, H1T 2M4, Canada
| | - Julie R Ingelfinger
- Harvard Medical School, Pediatric Nephrology Unit, Massachusetts General Hospital, 15 Parkman Street, WAC 709, Boston, MA, 02114-3117, USA
| | - Shao-Ling Zhang
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada.
| | - John S D Chan
- Département de medecine, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Saint Denis Street, Montréal, QC, H2X 0A9, Canada.
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4
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Hacken ET, Valentin R, Regis FFD, Sun J, Yin S, Werner L, Deng J, Gruber M, Wong J, Zheng M, Gill AL, Seiler M, Smith P, Thomas M, Buonamici S, Ghia EM, Kim E, Rassenti LZ, Burger JA, Kipps TJ, Meyerson ML, Bachireddy P, Wang L, Reed R, Neuberg D, Carrasco RD, Brooks AN, Letai A, Davids MS, Wu CJ. Splicing modulation sensitizes chronic lymphocytic leukemia cells to venetoclax by remodeling mitochondrial apoptotic dependencies. JCI Insight 2018; 3:121438. [PMID: 30282833 PMCID: PMC6237462 DOI: 10.1172/jci.insight.121438] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/29/2018] [Indexed: 12/30/2022] Open
Abstract
The identification of targetable vulnerabilities in the context of therapeutic resistance is a key challenge in cancer treatment. We detected pervasive aberrant splicing as a characteristic feature of chronic lymphocytic leukemia (CLL), irrespective of splicing factor mutation status, which was associated with sensitivity to the spliceosome modulator, E7107. Splicing modulation affected CLL survival pathways, including members of the B cell lymphoma-2 (BCL2) family of proteins, remodeling antiapoptotic dependencies of human and murine CLL cells. E7107 treatment decreased myeloid cell leukemia-1 (MCL1) dependence and increased BCL2 dependence, sensitizing primary human CLL cells and venetoclax-resistant CLL-like cells from an Eμ-TCL1-based adoptive transfer murine model to treatment with the BCL2 inhibitor venetoclax. Our data provide preclinical rationale to support the combination of venetoclax with splicing modulators to reprogram apoptotic dependencies in CLL for treating venetoclax-resistant CLL cases.
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Affiliation(s)
- Elisa ten Hacken
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Rebecca Valentin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Fara Faye D. Regis
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Jing Sun
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Shanye Yin
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Lillian Werner
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Jing Deng
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Michaela Gruber
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Jessica Wong
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Mei Zheng
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Amy L. Gill
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | | | - Peter Smith
- H3 Biomedicine Inc., Cambridge, Massachusetts, USA
| | | | | | - Emanuela M. Ghia
- Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Ekaterina Kim
- University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Laura Z. Rassenti
- Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Jan A. Burger
- University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Thomas J. Kipps
- Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Matthew L. Meyerson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute, Cambridge, Massachusetts, USA
| | - Pavan Bachireddy
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Lili Wang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Robin Reed
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Donna Neuberg
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Ruben D. Carrasco
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, USA.,Department of Oncologic Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Angela N. Brooks
- Department of Biomolecular Engineering, University of California, Santa Cruz, California, USA
| | - Anthony Letai
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Matthew S. Davids
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Catherine J. Wu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute, Cambridge, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
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5
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Singh PK, Weber A, Häcker G. The established and the predicted roles of dynein light chain in the regulation of mitochondrial apoptosis. Cell Cycle 2018; 17:1037-1047. [PMID: 30019621 DOI: 10.1080/15384101.2018.1464851] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
The mitochondrial pathway of apoptosis is regulated by the interplay between the members of Bcl-2 family. Within this family, BH3-only proteins are the sensors of apoptotic stimuli and can trigger apoptosis either by inhibiting the anti-apoptotic Bcl-2-family proteins or by directly activating the effectors Bax and Bak. An expanding body of research suggests that a number of non-Bcl-2 proteins can also interact with Bcl-2 proteins and contribute to the decision of cell fate. Dynein light chain (LC8, DYNLL or DLC), a hub protein and a dimerizing engine has been proposed to regulate the pro-apoptotic activity of two BH3-only proteins, Bim and Bmf. Our recent work has provided insight into the mechanisms through which DLC1 (DYNLL1) modulates Bim activity. Here we discuss the present day understanding of Bim-DLC interaction and endeavor to evaluate this interaction in the light of information from studies of DLC with other binding partners.
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Affiliation(s)
- Prafull Kumar Singh
- a Institute of Medical Microbiology and Hygiene, Faculty of Medicine , Medical Center-University of Freiburg , Freiburg , Germany
| | - Arnim Weber
- a Institute of Medical Microbiology and Hygiene, Faculty of Medicine , Medical Center-University of Freiburg , Freiburg , Germany
| | - Georg Häcker
- a Institute of Medical Microbiology and Hygiene, Faculty of Medicine , Medical Center-University of Freiburg , Freiburg , Germany.,b BIOSS Centre for Biological Signalling Studies , University of Freiburg , Freiburg , Germany
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6
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Akhter R, Saleem S, Saha A, Biswas SC. The pro-apoptotic protein Bmf co-operates with Bim and Puma in neuron death induced by β-amyloid or NGF deprivation. Mol Cell Neurosci 2018; 88:249-257. [PMID: 29499358 DOI: 10.1016/j.mcn.2018.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/23/2018] [Accepted: 02/25/2018] [Indexed: 12/22/2022] Open
Abstract
The pro-apoptotic Bcl-2 homology 3 domain only (BH3-only) proteins are central regulators of cell death in various physiological and pathological conditions, including Alzheimer's disease (AD). Bcl-2 modifying factor (Bmf) is one such BH3-only protein that is implicated in various death paradigms such as anoikis, seizures, cancer and autoimmunity. It also co-operates with other BH3-only proteins such as Bim in various death paradigms. However, its role in neurodegeneration is under-investigated. Here, we report for the first time the essential role of Bmf and its co-operativity with direct activator BH3-only proteins Bim and Puma in neuron death induced by beta-amyloid (Aβ) toxicity or NGF deprivation. Oligomeric Aβ is main pathologic species in AD and NGF deprivation is relevant for both developmental as well as pathologic neuron death. We find that Bmf over-expression causes cell death and Bmf knockdown protects neurons against death evoked by Aβ or NGF deprivation. We also find that Bmf co-operates with other important BH3-only proteins such as Bim and Puma in neuron death induced by Aβ or NGF deprivation. Simultaneous knocking down of these molecules by their respective shRNAs provide enhanced protection against Aβ. Taken together, our results elucidate the essential role of Bmf and its co-operative effects with already known neuron death inducers, Bim and Puma, in neuron death evoked by Aβ treatment or NGF deprivation.
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Affiliation(s)
- Rumana Akhter
- Cell Biology and Physiology Division, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700 032, India
| | - Suraiya Saleem
- Cell Biology and Physiology Division, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700 032, India
| | - Akash Saha
- Cell Biology and Physiology Division, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700 032, India
| | - Subhas Chandra Biswas
- Cell Biology and Physiology Division, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700 032, India.
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7
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Abstract
Hematopoietic cancers are often initiated by deregulation of the transcriptional machinery. Prominent among such regulators are the sequence-specific DNA-binding transcription factors (TFs), which bind to enhancer and promoter elements in the genome to control gene expression through the recruitment of cofactors. Remarkably, perturbing the function of even a single TF or cofactor can modulate the active enhancer landscape of a cell; conversely, knowledge of the enhancer configuration can be used to discover functionally important TFs in a given cellular process. Our expanding insight into enhancer function can be attributed to the emergence of genome-scale measurements of enhancer activity, which can be applied to virtually any cell type to expose regulatory mechanisms. Such approaches are beginning to reveal the abnormal enhancer configurations present in cancer cells, thereby providing a framework for understanding how transcriptional dysregulation can lead to malignancy. Here, we review the evidence for alterations in enhancer landscapes contributing to the pathogenesis of leukemia, a malignancy in which enhancer-binding proteins and enhancer DNA itself are altered via genetic mutation. We will also highlight examples of small molecules that reprogram the enhancer landscape of leukemia cells in association with therapeutic benefit.
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8
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Guikema JE, Amiot M, Eldering E. Exploiting the pro-apoptotic function of NOXA as a therapeutic modality in cancer. Expert Opin Ther Targets 2017; 21:767-779. [DOI: 10.1080/14728222.2017.1349754] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Jeroen E Guikema
- Department of Pathology, Academic Medical Center, Amsterdam, The Netherlands
- Lymphoma and Myeloma Center Amsterdam (LYMMCARE), The Netherlands
| | - Martine Amiot
- CRCINA, INSERM, CNRS, Université d’Angers, Université de Nantes, Nantes, France
| | - Eric Eldering
- Department of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands
- Lymphoma and Myeloma Center Amsterdam (LYMMCARE), The Netherlands
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9
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Hayakawa K, Formica AM, Brill-Dashoff J, Shinton SA, Ichikawa D, Zhou Y, Morse HC, Hardy RR. Early generated B1 B cells with restricted BCRs become chronic lymphocytic leukemia with continued c-Myc and low Bmf expression. J Exp Med 2016; 213:3007-3024. [PMID: 27899442 PMCID: PMC5154941 DOI: 10.1084/jem.20160712] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 09/01/2016] [Accepted: 10/21/2016] [Indexed: 01/22/2023] Open
Abstract
Hayakawa et al. show that distinctive B-lineage progression from B-1 development allows for generation of B1a cells with restricted BCRs and self-renewal capacity, both contributing to potential for CLL progression. In mice, generation of autoreactive CD5+ B cells occurs as a consequence of BCR signaling induced by (self)-ligand exposure from fetal/neonatal B-1 B cell development. A fraction of these cells self-renew and persist as a minor B1 B cell subset throughout life. Here, we show that transfer of early generated B1 B cells from Eμ-TCL1 transgenic mice resulted in chronic lymphocytic leukemia (CLL) with a biased repertoire, including stereotyped BCRs. Thus, B1 B cells bearing restricted BCRs can become CLL during aging. Increased anti-thymocyte/Thy-1 autoreactive (ATA) BCR cells in the B1 B cell subset by transgenic expression yielded spontaneous ATA B-CLL/lymphoma incidence, enhanced by TCL1 transgenesis. In contrast, ATA B-CLL did not develop from other B cell subsets, even when the identical ATA BCR was expressed on a Thy-1 low/null background. Thus, both a specific BCR and B1 B cell context were important for CLL progression. Neonatal B1 B cells and their CLL progeny in aged mice continued to express moderately up-regulated c-Myc and down-regulated proapoptotic Bmf, unlike most mature B cells in the adult. Thus, there is a genetic predisposition inherent in B-1 development generating restricted BCRs and self-renewal capacity, with both features contributing to potential for progression to CLL.
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Affiliation(s)
| | | | | | | | | | - Yan Zhou
- Fox Chase Cancer Center, Philadelphia, PA 19111
| | - Herbert C Morse
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852
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10
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Slinger E, Wensveen FM, Guikema JE, Kater AP, Eldering E. Chronic lymphocytic leukemia development is accelerated in mice with deficiency of the pro-apoptotic regulator NOXA. Haematologica 2016; 101:e374-7. [PMID: 27479816 DOI: 10.3324/haematol.2016.142323] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Erik Slinger
- Department of Hematology, Academic Medical Center, The Netherlands Department of Experimental Immunology, Academic Medical Center, The Netherlands
| | - Felix M Wensveen
- Department of Experimental Immunology, Academic Medical Center, The Netherlands
| | - Jeroen E Guikema
- Department of Pathology, Academic Medical Center, The Netherlands Lymphoma and Myeloma Center Amsterdam (LYMMCARE), The Netherlands
| | - Arnon P Kater
- Department of Hematology, Academic Medical Center, The Netherlands Lymphoma and Myeloma Center Amsterdam (LYMMCARE), The Netherlands
| | - Eric Eldering
- Department of Experimental Immunology, Academic Medical Center, The Netherlands Lymphoma and Myeloma Center Amsterdam (LYMMCARE), The Netherlands
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11
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Labi V, Erlacher M. How cell death shapes cancer. Cell Death Dis 2015; 6:e1675. [PMID: 25741600 PMCID: PMC4385913 DOI: 10.1038/cddis.2015.20] [Citation(s) in RCA: 181] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 12/28/2014] [Accepted: 01/02/2015] [Indexed: 12/20/2022]
Abstract
Apoptosis has been established as a mechanism of anti-cancer defense. Members of the BCL-2 family are critical mediators of apoptotic cell death in health and disease, often found to be deregulated in cancer and believed to lead to the survival of malignant clones. However, over the years, a number of studies pointed out that a model in which cell death resistance unambiguously acts as a barrier against malignant disease might be too simple. This is based on paradoxical observations made in tumor patients as well as mouse models indicating that apoptosis can indeed drive tumor formation, at least under certain circumstances. One possible explanation for this phenomenon is that apoptosis can promote proliferation critically needed to compensate for cell loss, for example, upon therapy, and to restore tissue homeostasis. However, this, at the same time, can promote tumor development by allowing expansion of selected clones. Usually, tissue resident stem/progenitor cells are a major source for repopulation, some of them potentially carrying (age-, injury- or therapy-induced) genetic aberrations deleterious for the host. Thereby, apoptosis might drive genomic instability by facilitating the emergence of pathologic clones during phases of proliferation and subsequent replication stress-associated DNA damage. Tumorigenesis initiated by repeated cell attrition and repopulation, as confirmed in different genetic models, has parallels in human cancers, exemplified in therapy-induced secondary malignancies and myelodysplastic syndromes in patients with congenital bone marrow failure syndromes. Here, we aim to review evidence in support of the oncogenic role of stress-induced apoptosis.
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Affiliation(s)
- V Labi
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin 13125, Germany
- Immune Regulation and Cancer, Max-Delbrück-Center for Molecular Medicine, Robert Rössle-Strasse 10, 13125 Berlin, Germany. Tel: +49 30 9406 3462; Fax: +49 30 9406 2390; E-mail:
| | - M Erlacher
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology and Oncology, University Medical Center of Freiburg, Freiburg 79106, Germany
- Freiburg Institute for Advanced Studies, University of Freiburg, Freiburg 79104, Germany
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12
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Genome-wide association study identifies multiple risk loci for chronic lymphocytic leukemia. Nat Genet 2013; 45:868-76. [PMID: 23770605 PMCID: PMC3729927 DOI: 10.1038/ng.2652] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 05/02/2013] [Indexed: 12/12/2022]
Abstract
Genome-wide association studies (GWAS) have previously identified 13 loci associated with risk of chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL). To identify additional CLL susceptibility loci, we conducted the largest meta-analysis for CLL thus far, including four GWAS with a total of 3,100 individuals with CLL (cases) and 7,667 controls. In the meta-analysis, we identified ten independent associated SNPs in nine new loci at 10q23.31 (ACTA2 or FAS (ACTA2/FAS), P=1.22×10(-14)), 18q21.33 (BCL2, P=7.76×10(-11)), 11p15.5 (C11orf21, P=2.15×10(-10)), 4q25 (LEF1, P=4.24×10(-10)), 2q33.1 (CASP10 or CASP8 (CASP10/CASP8), P=2.50×10(-9)), 9p21.3 (CDKN2B-AS1, P=1.27×10(-8)), 18q21.32 (PMAIP1, P=2.51×10(-8)), 15q15.1 (BMF, P=2.71×10(-10)) and 2p22.2 (QPCT, P=1.68×10(-8)), as well as an independent signal at an established locus (2q13, ACOXL, P=2.08×10(-18)). We also found evidence for two additional promising loci below genome-wide significance at 8q22.3 (ODF1, P=5.40×10(-8)) and 5p15.33 (TERT, P=1.92×10(-7)). Although further studies are required, the proximity of several of these loci to genes involved in apoptosis suggests a plausible underlying biological mechanism.
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13
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Bmf upregulation through the AMP-activated protein kinase pathway may protect the brain from seizure-induced cell death. Cell Death Dis 2013; 4:e606. [PMID: 23618904 PMCID: PMC3668628 DOI: 10.1038/cddis.2013.136] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Prolonged seizures (status epilepticus, SE) can cause neuronal death within brain regions such as the hippocampus. This may contribute to impairments in cognitive functioning and trigger or exacerbate epilepsy. Seizure-induced neuronal death is mediated, at least in part, by apoptosis-associated signaling pathways. Indeed, mice lacking certain members of the potently proapoptotic BH3-only subfamily of Bcl-2 proteins are protected against hippocampal damage caused by status epilepticus. The recently identified BH3-only protein Bcl-2-modifying factor (Bmf) normally interacts with the cytoskeleton, but upon certain cellular stresses, such as loss of extracellular matrix adhesion or energy crisis, Bmf relocalizes to mitochondria, where it can promote Bax activation and mitochondrial dysfunction. Although Bmf has been widely reported in the hematopoietic system to exert a proapoptotic effect, no studies have been undertaken in models of neurological disorders. To examine whether Bmf is important for seizure-induced neuronal death, we studied Bmf induction after prolonged seizures induced by intra-amygdala kainic acid (KA) in mice, and examined the effect of Bmf-deficiency on seizures and damage caused by SE. Seizures triggered an early (1-8 h) transcriptional activation and accumulation of Bax in the cell death-susceptible hippocampal CA3 subfield. Bmf mRNA was biphasically upregulated beginning at 1 h after SE and returning to normal by 8 h, while again being found elevated in the hippocampus of epileptic mice. Bmf upregulation was prevented by Compound C, an inhibitor of adenosine monophosphate-activated protein kinase, indicating Bmf expression may be induced in response to bioenergetic stress. Bmf-deficient mice showed normal sensitivity to the convulsant effects of KA, but, surprisingly, displayed significantly more neuronal death in the hippocampal CA1 and CA3 subfields after SE. These are the first studies investigating Bmf in a model of neurologic injury, and suggest that Bmf may protect neurons against seizure-induced neuronal death in vivo.
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Lau GJ, Godin N, Maachi H, Lo CS, Wu SJ, Zhu JX, Brezniceanu ML, Chénier I, Fragasso-Marquis J, Lattouf JB, Ethier J, Filep JG, Ingelfinger JR, Nair V, Kretzler M, Cohen CD, Zhang SL, Chan JS. Bcl-2-modifying factor induces renal proximal tubular cell apoptosis in diabetic mice. Diabetes 2012; 61:474-84. [PMID: 22210314 PMCID: PMC3266424 DOI: 10.2337/db11-0141] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
This study investigated the mechanisms underlying tubular apoptosis in diabetes by identifying proapoptotic genes that are differentially upregulated by reactive oxygen species in renal proximal tubular cells (RPTCs) in models of diabetes. Total RNAs isolated from renal proximal tubules (RPTs) of 20-week-old heterozygous db/m+, db/db, and db/db catalase (CAT)-transgenic (Tg) mice were used for DNA chip microarray analysis. Real-time quantitative PCR assays, immunohistochemistry, and mice rendered diabetic with streptozotocin were used to validate the proapoptotic gene expression in RPTs. Cultured rat RPTCs were used to confirm the apoptotic activity and regulation of proapoptotic gene expression. Additionally, studies in kidney tissues from patients with and without diabetes were used to confirm enhanced proapoptotic gene expression in RPTs. Bcl-2-modifying factor (Bmf) was differentially upregulated (P<0.01) in RPTs of db/db mice compared with db/m+ and db/db CAT-Tg mice and in RPTs of streptozotocin-induced diabetic mice in which insulin reversed this finding. In vitro, Bmf cDNA overexpression in rat RPTCs coimmunoprecipated with Bcl-2, enhanced caspase-3 activity, and promoted apoptosis. High glucose (25 mmol/L) induced Bmf mRNA expression in RPTCs, whereas rotenone, catalase, diphenylene iodinium, and apocynin decreased it. Knockdown of Bmf with small interfering RNA reduced high glucose-induced apoptosis in RPTCs. More important, enhanced Bmf expression was detected in RPTs of kidneys from patients with diabetes. These data demonstrate differential upregulation of Bmf in diabetic RPTs and suggest a potential role for Bmf in regulating RPTC apoptosis and tubular atrophy in diabetes.
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Affiliation(s)
- Garnet J. Lau
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Nicolas Godin
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Hasna Maachi
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Chao-Sheng Lo
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Shyh-Jong Wu
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Jian-Xin Zhu
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Marie-Luise Brezniceanu
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Isabelle Chénier
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Joelle Fragasso-Marquis
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Jean-Baptiste Lattouf
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Jean Ethier
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - Janos G. Filep
- Research Centre, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada
| | - Julie R. Ingelfinger
- Pediatric Nephrology Unit, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Viji Nair
- Nephrology/Internal Medicine, Center for Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan
| | - Matthias Kretzler
- Nephrology/Internal Medicine, Center for Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan
| | - Clemens D. Cohen
- Division of Nephrology, Institute of Physiology, University Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | - Shao-Ling Zhang
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
| | - John S.D. Chan
- Centre de recherche du Centre hospitalier de l’Université de Montréal (CRCHUM), Hôtel-Dieu Hospital, Université de Montréal, Montreal, Quebec, Canada
- Corresponding author: John S.D. Chan,
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15
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Liu J, Xiao Y, Xiong HM, Li J, Huang B, Zhang HB, Feng DQ, Chen XM, Wang XZ. Alternative splicing of apoptosis-related genes in imatinib-treated K562 cells identified by exon array analysis. Int J Mol Med 2011; 29:690-8. [PMID: 22211240 PMCID: PMC3577368 DOI: 10.3892/ijmm.2011.872] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Accepted: 12/02/2011] [Indexed: 01/22/2023] Open
Abstract
Imatinib is the therapeutic standard for newly diagnosed patients with chronic myeloid leukemia (CML). In these patients, imatinib has been shown to induce an apoptotic response specifically in cells expressing the oncogenic fusion protein BCR-ABL. Previous studies in our lab revealed that imatinib-induced apoptosis in K562 cells involves a shift in production of Bcl-x splice isoforms towards the pro-apoptotic Bcl-xS splice variant. Here, we report the findings from our subsequent study to identify other apoptosis-related genes that are differentially spliced in response to imatinib treatment. Gene expression profiling of imatinib-treated K562 cells was performed by the Affymetrix GeneChip® Human Exon 1.0 ST array, and differences in exon-level expression and alternative splicing were analyzed using the easyExon software. Detailed analysis by reverse transcription-PCR (RT-PCR) and sequencing of key genes confirmed the experimental results of the exon array. Our results suggest that imatinib treatment of K562 cells causes a transcriptional shift towards alternative splicing in a large number of apoptotic genes. The present study provides insight into the molecular character of apoptotic leukemia cells and may help to improve the mechanism of imatinib therapy in patients with CML.
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Affiliation(s)
- Jing Liu
- Department of Clinical Laboratory, Second Affiliated Hospital of Nanchang University, Nanchang 330006, PR China
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16
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Grespi F, Soratroi C, Krumschnabel G, Sohm B, Ploner C, Geley S, Hengst L, Häcker G, Villunger A. BH3-only protein Bmf mediates apoptosis upon inhibition of CAP-dependent protein synthesis. Cell Death Differ 2010; 17:1672-83. [PMID: 20706276 PMCID: PMC2953534 DOI: 10.1038/cdd.2010.97] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Tight transcriptional regulation, alternative splicing and/or post-translational modifications of BH3-only proteins fine-tune their proapoptotic function. In this study, we characterize the gene locus of the BH3-only protein Bmf (Bcl-2-modifying factor) and describe the generation of two major isoforms from a common transcript in which initiation of protein synthesis involves leucine-coding CUG. Bmf(CUG) and the originally described isoform, Bmf-short, display comparable binding affinities to prosurvival Bcl-2 family members, localize preferentially to the outer mitochondrial membrane and induce rapid Bcl-2-blockable apoptosis. Notably, endogenous Bmf expression is induced on forms of cell stress known to cause repression of the CAP-dependent translation machinery such as serum deprivation, hypoxia, inhibition of the PI3K/AKT pathway or mTOR, as well as direct pharmacological inhibition of the eukaryotic translation initiation factor eIF-4E. Knock down or deletion of Bmf reduces apoptosis under some of these conditions, demonstrating that Bmf can act as a sentinel for stress-impaired CAP-dependent protein translation machinery.
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Affiliation(s)
- F Grespi
- Innsbruck Medical University, Biocenter, Austria
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17
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Intrinsically disordered proteins in bcl-2 regulated apoptosis. Int J Mol Sci 2010; 11:1808-24. [PMID: 20480043 PMCID: PMC2871139 DOI: 10.3390/ijms11041808] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 03/23/2010] [Accepted: 04/14/2010] [Indexed: 12/11/2022] Open
Abstract
Intrinsic cell death is mediated by interaction between pro-apoptotic and pro-survival proteins of the B-cell lymphoma-2 (Bcl-2) family. Members of this family are either intrinsically disordered or contain intrinsically disordered regions/domains that are critical to their function. Alternate splicing and post-translational modifications can determine the extent of these disordered regions and are critical for regulating Bcl-2 proteins. Conformational plasticity and structural transitions characterize the interactions within the Bcl-2 family, with conserved sequence motifs on both binding partners required for their molecular recognition.
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18
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Abstract
Oncogenic c-Myc is known to balance excessive proliferation by apoptosis that can be triggered by p53-dependent and p53-independent signaling networks. Here, we provide evidence that the BH3-only proapoptotic Bcl-2 family members Bcl-2 modifying factor (Bmf) and Bcl-2 antagonist of cell death (Bad) are potent antagonists of c-Myc-driven B-cell lymphomagenesis. Tumor formation was preceded by the accumulation of preneoplastic pre-B and immature immunoglobulin M-positive (IgM(+)) B cells in hematopoietic organs of Emu-myc/bmf(-/-) mice, whereas Emu-myc/bad(-/-) mice showed an increase of pre-B cells limited to the spleen. Although the loss of Bad had no impact on the tumor immunophenotype, Bmf deficiency favored the development of IgM(+) B cell over pre-B cell tumors. This phenomenon was caused by a strong protection of immature IgM(+) B cells from oncogene-driven apoptosis caused by loss of bmf and c-Myc-induced repression of Bmf expression in premalignant pre-B cells. Steady-state levels of B-cell apoptosis also were reduced in the absence of Bad, in support of its role as a sentinel for trophic factor-deprivation. Loss of Bmf reduced the pressure to inactivate p53, whereas Bad deficiency did not, identifying Bmf as a novel component of the p53-independent tumor suppressor pathway triggered by c-Myc.
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19
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Piñon JD, Labi V, Egle A, Villunger A. Bim and Bmf in tissue homeostasis and malignant disease. Oncogene 2009; 27 Suppl 1:S41-52. [PMID: 19641506 DOI: 10.1038/onc.2009.42] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Among all BH3-only proteins known to date, most information is available on the biological role and function of Bim (Bcl-2 interacting mediator of cell death)/BOD (Bcl-2 related ovarian death agonist), whereas little is still known about its closest relative, Bcl-2 modifying factor (Bmf). Although Bim has been implicated in the regulation of cell death induction in multiple cell types and tissues in response to a large number of stimuli, including growth factor or cytokine deprivation, calcium flux, ligation of antigen receptors on T and B cells, glucocorticoid or loss of adhesion, Bmf seems to play a more restricted role by supporting Bim in some of these cell death processes. This review aims to highlight similarities between Bim and Bmf function in apoptosis signaling and their role in normal development and disease.
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Affiliation(s)
- J D Piñon
- Laboratory for Immunological and Molecular Cancer Research, University Hospital Salzburg, Salzburg, Austria
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20
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Lomonosova E, Chinnadurai G. BH3-only proteins in apoptosis and beyond: an overview. Oncogene 2009; 27 Suppl 1:S2-19. [PMID: 19641503 DOI: 10.1038/onc.2009.39] [Citation(s) in RCA: 308] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BH3-only BCL-2 family proteins are effectors of canonical mitochondrial apoptosis. They discharge their pro-apoptotic functions through BH1-3 pro-apoptotic proteins such as BAX and BAK, while their activity is suppressed by BH1-4 anti-apoptotic BCL-2 family members. The precise mechanism by which BH3-only proteins mediate apoptosis remains unresolved. The existing data are consistent with three mutually non-exclusive models (1) displacement of BH1-3 proteins from complexes with BH1-4 proteins; (2) direct interaction with and conformational activation of BH1-3 proteins; and (3) membrane insertion and membrane remodeling. The BH3-only proteins appear to play critical roles in restraining cancer and inflammatory diseases such as rheumatoid arthritis. Molecules that mimic the effect of BH3-only proteins are being used in treatments against these diseases. The cell death activity of a subclass of BH3-only members (BNIP3 and BNIP3L) is linked to cardiomyocyte loss during heart failure. In addition to their established role in apoptosis, several BH3-only members also regulate diverse cellular functions in cell-cycle regulation, DNA repair and metabolism. Several members are implicated in the induction of autophagy and autophagic cell death, possibly through unleashing of the BH3-only autophagic effector Beclin 1 from complexes with BCL-2/BCL-xL. The Chapters included in the current Oncogene Review issues provide in-depth discussions on various aspects of major BH3-only proteins.
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Affiliation(s)
- E Lomonosova
- Institute for Molecular Virology, Saint Louis University School of Medicine, Doisy Research Center, St Louis, MO 63104, USA
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21
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Abstract
The mainstay of therapy of chronic lymphocytic leukemia (CLL) is cytotoxic chemotherapy; however, CLL is still an incurable disease with resistance to therapy developing in the majority of patients. In recent years, our understanding of the biological basis of CLL pathogenesis has substantially improved and novel treatment strategies are emerging. Tailoring and individualizing therapy according to the molecular and cellular biology of the disease is on the horizon, and advances with targeted agents such as monoclonal antibodies combined with traditional chemotherapy have lead to improved remission rates. The proposed key role of the B-cell receptor (BCR) in CLL pathogenesis has led to a number of possible opportunities for therapeutic exploitation. We are beginning to understand that the microenvironment is of utmost importance in CLL because certain T-cell subsets and stromal cells support the outgrowth and development of the malignant clone. Furthermore, an increase in our understanding of the deregulated cell-death machinery in CLL is a prerequisite to developing new targeted strategies that might be more effective in engaging with the cell-death machinery. This Review summarizes the progress made in understanding these features of CLL biology and describes novel treatment strategies that have also been exploited in current clinical trials.
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22
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Kuroda J, Taniwaki M. Involvement of BH3-only proteins in hematologic malignancies. Crit Rev Oncol Hematol 2008; 71:89-101. [PMID: 19022681 DOI: 10.1016/j.critrevonc.2008.10.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2008] [Revised: 09/18/2008] [Accepted: 10/09/2008] [Indexed: 12/25/2022] Open
Abstract
The interaction between anti-apoptotic and pro-apoptotic members of the Bcl-2 family proteins determines life or death for cancer cells. In this context, BH3-only proteins (such as Bim), members of the pro-apoptotic Bcl-2 family proteins, act as key initiators of apoptosis by activating Bax and Bak through liberating them from anti-apoptotic Bcl-2 members. This then leads to the disruption of mitochondrial outer membrane, and eventually promotes proteolytic cascades for cellular dismantling. We here review the growing evidence of how BH3-only proteins are involved in tumorigenesis and in apoptosis induced by anti-cancer agents in hematologic malignancies. A deeper understanding of the roles of BH3-only proteins in cell death regulation may yield crucial insights for the further development of more effective and rational cell killing strategies. Recent developments in the direct therapeutic manipulation of Bcl-2 proteins using BH3-mimicking agents, such as ABT-737 or GX15-070, for hematologic malignancies are also summarized.
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Affiliation(s)
- Junya Kuroda
- Division of Hematology and Oncology, Department of Medicine, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566, Japan.
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23
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Labi V, Erlacher M, Kiessling S, Manzl C, Frenzel A, O'Reilly L, Strasser A, Villunger A. Loss of the BH3-only protein Bmf impairs B cell homeostasis and accelerates gamma irradiation-induced thymic lymphoma development. ACTA ACUST UNITED AC 2008; 205:641-55. [PMID: 18299399 PMCID: PMC2275386 DOI: 10.1084/jem.20071658] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Members of the Bcl-2 protein family play crucial roles in the maintenance of tissue homeostasis by regulating apoptosis in response to developmental cues or exogenous stress. Proapoptotic BH3-only members of the Bcl-2 family are essential for initiation of cell death, and they function by activating the proapoptotic Bcl-2 family members Bax and/or Bak, either directly or indirectly through binding to prosurvival Bcl-2 family members. Bax and Bak then elicit the downstream events in apoptosis signaling. Mammals have at least eight BH3-only proteins and they are activated in a stimulus-specific, as well as a cell type–specific, manner. We have generated mice lacking the BH3-only protein Bcl-2–modifying factor (Bmf) to investigate its role in cell death signaling. Our studies reveal that Bmf is dispensable for embryonic development and certain forms of stress-induced apoptosis, including loss of cell attachment (anoikis) or UV irradiation. Remarkably, loss of Bmf protected lymphocytes against apoptosis induced by glucocorticoids or histone deacetylase inhibition. Moreover, bmf−/− mice develop a B cell–restricted lymphadenopathy caused by the abnormal resistance of these cells to a range of apoptotic stimuli. Finally, Bmf-deficiency accelerated the development of γ irradiation–induced thymic lymphomas. Our results demonstrate that Bmf plays a critical role in apoptosis signaling and can function as a tumor suppressor.
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Affiliation(s)
- Verena Labi
- Division of Developmental Immunology, Biocenter, Innsbruck Medical University, 6020 Innsbruck, Austria
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24
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Gómez-Esquer F, Palomar MA, Rivas I, Delcán J, Linares R, Díaz-Gil G. Characterization of the BH3 protein Bmf in Gallus gallus: identification of a novel chicken-specific isoform. Gene 2007; 407:21-9. [PMID: 17967519 DOI: 10.1016/j.gene.2007.09.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 09/11/2007] [Accepted: 09/19/2007] [Indexed: 01/01/2023]
Abstract
Bmf is a proapoptotic member of the BH3-only subgroup of Bcl-2 family proteins, which is associated to myosin V motors by binding to the dynein light chain 2 (DLC2). It acts as a sentinel detecting intracellular damages on the main cytoskeletal structures. The cloning and characterization of the chicken (Gallus gallus) Bmf cDNA and splicing variant is described in this report. The Bmf cDNA was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) using oligonucleotide primers derived from in silico sequences. The chicken Bmf cDNA encodes a protein of 193 amino acids, showing homology to mammalian Bmf proteins. A splicing variant of the chicken Bmf (Bmf(S), short isoform of Bmf) coding a protein of 118 amino acids was also identified. This is the first Bmf isoform identified so far which lacks the DLC2-binding domain although retaining the BH3 domain. Both chicken Bmf isoforms induced apoptosis 24 h after transfection in MCF7 and HeLa cell lines, but chicken Bmf(S) exhibits a higher proapoptotic activity. In addition, mRNA expression analysis showed that chicken Bmf transcription is ubiquitous in all embryo developmental stages, suggesting a role for this protein in the control of the development process.
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Affiliation(s)
- Francisco Gómez-Esquer
- Departamento de Ciencias de la Salud III, Universidad Rey Juan Carlos, Avenida de Atenas S/N, Alcorcón, Madrid, Spain
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25
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Iglesias-Serret D, de Frias M, Santidrián AF, Coll-Mulet L, Cosialls AM, Barragán M, Domingo A, Gil J, Pons G. Regulation of the proapoptotic BH3-only protein BIM by glucocorticoids, survival signals and proteasome in chronic lymphocytic leukemia cells. Leukemia 2006; 21:281-7. [PMID: 17151701 DOI: 10.1038/sj.leu.2404483] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Glucocorticoids induce apoptosis in chronic lymphocytic leukemia (CLL) cells through a caspase-dependent mechanism. However, their mechanism of action remains unknown. We have studied the regulation of the proapoptotic BH3-only Bcl-2 interacting mediator of cell death (BIM) in CLL cells. We demonstrate that glucocorticoids upregulate BIM at protein and mRNA levels. We have investigated the ability of different survival signals, such as 12-O-tetradecanoylphorbol 13-acetate (TPA), stromal cell-derived factor-1alpha (SDF-1alpha), interleukin 4 (IL-4) and B-cell receptor (BCR) activation, to influence the levels of BIM and its induction by glucocorticoids. TPA downregulates BIM(EL) by extracellular signal-regulated kinase (ERK)-mediated BIM phosphorylation and further proteasome-mediated degradation. However, SDF-1alpha and BCR activation induce transient BIM phosphorylation, without protein degradation. Proteasome inhibitors do not modify the levels of BIM with respect to untreated cells. However, they induce apoptosis and inhibit TPA-induced BIM(EL) degradation, leading to its accumulation. In conclusion, the results implicate BIM in glucocorticoid-induced apoptosis in CLL cells. BIM(EL) phosphorylation through the ERK pathway targets the protein for proteasomal degradation.
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Affiliation(s)
- D Iglesias-Serret
- Departament de Ciències Fisiològiques II, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
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26
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Smit LA, Hallaert DYH, Spijker R, de Goeij B, Jaspers A, Kater AP, van Oers MHJ, van Noesel CJM, Eldering E. Differential Noxa/Mcl-1 balance in peripheral versus lymph node chronic lymphocytic leukemia cells correlates with survival capacity. Blood 2006; 109:1660-8. [PMID: 17038534 DOI: 10.1182/blood-2006-05-021683] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The gradual accumulation of chronic lymphocytic leukemia (B-CLL) cells is presumed to derive from proliferation centers in lymph nodes and bone marrow. To what extent these cells possess the purported antiapoptotic phenotype of peripheral B-CLL cells is unknown. Recently, we have described that, in B-CLL samples from peripheral blood, aberrant apoptosis gene expression was not limited to protective changes but also included increased levels of proapoptotic BH3-only member Noxa. Here, we compare apoptosis gene profiles from peripheral blood B-CLL (n = 15) with lymph node B-CLL (> 90% CD5+/CD19+/CD23+ lymphocytes with Ki67+ centers; n = 9). Apart from expected differences in Survivin and Bcl-xL, a prominent distinction with peripheral B-CLL cells was the decreased averaged level of Noxa in lymph nodes. Mcl-1 protein expression showed a reverse trend. Noxa expression could be reduced also in vitro by CD40 stimulation of peripheral blood B-CLL. Direct manipulation of Noxa protein levels was achieved by proteasome inhibition in B-CLL and via RNAi in model cell lines. In each instance, cell viability was directly linked with Noxa levels. These data indicate that suppression of Noxa in the lymph node environment contributes to the persistence of B-CLL at these sites and suggest that therapeutic targeting of Noxa might be beneficial.
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Affiliation(s)
- Laura A Smit
- Department of Pathology, Academic Medical Center, Amsterdam, The Netherlands
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Thomadaki H, Scorilas A. BCL2 family of apoptosis-related genes: functions and clinical implications in cancer. Crit Rev Clin Lab Sci 2006; 43:1-67. [PMID: 16531274 DOI: 10.1080/10408360500295626] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
One of the most effective ways to combat different types of cancer is through early diagnosis and administration of effective treatment, followed by efficient monitoring that will allow physicians to detect relapsing disease and treat it at the earliest possible time. Apoptosis, a normal physiological form of cell death, is critically involved in the regulation of cellular homeostasis. Dysregulation of programmed cell death mechanisms plays an important role in the pathogenesis and progression of cancer as well as in the responses of tumours to therapeutic interventions. Many members of the BCL2 (B-cell CLL/lymphoma 2; Bcl-2) family of apoptosis-related genes have been found to be differentially expressed in various malignancies, and some are useful prognostic cancer biomarkers. We have recently cloned a new member of this family, BCL2L12, which was found to be differentially expressed in many tumours. Most of the BCL2 family genes have been found to play a central regulatory role in apoptosis induction. Results have made it clear that a number of coordinating alterations in the BCL2 family of genes must occur to inhibit apoptosis and provoke carcinogenesis in a wide variety of cancers. However, more research is required to increase our understanding of the extent to which and the mechanisms by which they are involved in cancer development, providing the basis for earlier and more accurate cancer diagnosis, prognosis and therapeutic intervention that targets the apoptosis pathways. In the present review, we describe current knowledge of the function and molecular characteristics of a series of classic but also newly discovered genes of the BCL2 family as well as their implications in cancer development, prognosis and treatment.
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Affiliation(s)
- Hellinida Thomadaki
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Athens, Panepistimiopolis, 15701 Athens, Greece
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Labi V, Erlacher M, Kiessling S, Villunger A. BH3-only proteins in cell death initiation, malignant disease and anticancer therapy. Cell Death Differ 2006; 13:1325-38. [PMID: 16645634 DOI: 10.1038/sj.cdd.4401940] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Induction of apoptosis in tumour cells, either by direct activation of the death receptor pathway using agonistic antibodies or recombinant ligands, or direct triggering of the Bcl-2-regulated intrinsic apoptosis pathway by small molecule drugs, carries high hopes to overcome the shortcomings of current anticancer therapies. The latter therapy concept builds on a more detailed understanding of how Bcl-2-like molecules maintain mitochondrial integrity and how BH3-only proteins and Bax/Bak-like molecules can undermine it. Means to unleash the apoptotic potential of BH3-only proteins in tumour cells, or bypass the need for BH3-only proteins by blocking possible interactions of Bcl-2-like prosurvival molecules with Bax and/or Bak allowing their direct activation, constitute interesting options for the design of novel anticancer therapies.
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Affiliation(s)
- V Labi
- Division of Experimental Pathophysiology and Immunology, Biocenter, Innsbruck Medical University, Austria
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29
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Beswick RW, Ambrose HE, Wagner SD. Nocodazole, a microtubule depolymerising agent, induces apoptosis of chronic lymphocytic leukaemia cells associated with changes in Bcl-2 phosphorylation and expression. Leuk Res 2006; 30:427-36. [PMID: 16162358 DOI: 10.1016/j.leukres.2005.08.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2005] [Accepted: 08/08/2005] [Indexed: 02/07/2023]
Abstract
Microtubule active drugs are used in the treatment of malignancies and their mechanism of action in cycling cells is to produce mitotic arrest followed by apoptosis. In this study, we investigate in detail the specificity and mechanism by which a microtubule de-polymerising agent, nocodazole, induces apoptosis in non-cyclingm, i.e. G(0)/G(1), chronic lymphocytic leukaemia (CLL) B-cells. The majority of cases of CLL are sensitive (IC(50)<or=16 microM) but normal peripheral blood B-cells, which are also in G(0)/G(1), are resistant to the maximum in vitro concentration of this agent. Taxol, a microtubule stabilising drug does not kill CLL cells suggesting a specific effect of nocodazole. The mechanism of apoptosis involves mitochondrial membrane depolarisation, activation of caspases and cleavage of PARP. Nocodazole causes two patterns of change to Bcl-2 expression. In one there is increase in expression of the serine-70 phosphorylated form of Bcl-2 and in the other total Bcl-2 expression is reduced. Collectively the data shows that sensitivity to nocodazole-induced apoptosis is a feature of chronic lymphocytic leukaemia and suggests that newer microtubule active agents be systematically investigated for their effectiveness in this condition.
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Affiliation(s)
- Richard W Beswick
- Division of Investigative Sciences, Department of Haematology, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
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30
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Zhang Y, Adachi M, Kawamura R, Imai K. Bmf is a possible mediator in histone deacetylase inhibitors FK228 and CBHA-induced apoptosis. Cell Death Differ 2006; 13:129-40. [PMID: 15947789 DOI: 10.1038/sj.cdd.4401686] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Histone deacetylase (HDAC) inhibitors modify transcription of selected genes and eventually induce apoptosis. However, molecular mechanisms for their proapoptotic activity remain unclear. We here demonstrate that HDAC inhibitors FK228 and CBHA preferentially upregulated the BH3-only protein Bmf in a broad range of cancer cells. In contrast, HDAC1 overexpression distinctly reduced Bmf expression. FK228 induced histones H3 and H4 acetylation at Bmf promoter region, but not at its 3' region, suggesting that histone hyperacetylation causes Bmf transcriptional activation. Knockdown of Bmf transcripts rescued cells from FK228 or CBHA-induced cell death, disruption of mitochondrial membrane potential (DeltaPsim) and DNA fragmentation. Taken together, FK228 and CBHA activate Bmf transcription by histone hyperacetylation at its promoter region, and inhibition of this action decreased their proapoptotic activity, thereby highlighting a central role of Bmf in HDAC inhibitor-mediated apoptosis.
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Affiliation(s)
- Y Zhang
- Division of Molecular Oncology and Molecular Diagnosis, Graduate School of Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
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31
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Mackus WJM, Kater AP, Grummels A, Evers LM, Hooijbrink B, Kramer MHH, Castro JE, Kipps TJ, van Lier RAW, van Oers MHJ, Eldering E. Chronic lymphocytic leukemia cells display p53-dependent drug-induced Puma upregulation. Leukemia 2005; 19:427-34. [PMID: 15674362 DOI: 10.1038/sj.leu.2403623] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We investigated the apoptosis gene expression profile of chronic lymphocytic leukemia (CLL) cells in relation to (1) normal peripheral and tonsillar B-cell subsets, (2) IgV(H) mutation status, and (3) effects of cytotoxic drugs. In accord with their noncycling, antiapoptotic status in vivo, CLL cells displayed high constitutive expression of Bcl-2 and Flip mRNA, while Survivin, Bid and Bik were absent. Paradoxically, along with these antiapoptotic genes CLL cells had high-level expression of proapoptotic BH3-only proteins Bmf and Noxa. Treatment of CLL cells with fludarabine induced only the proapoptotic genes Bax and Puma in a p53-dependent manner. Interestingly, the degree of Puma induction was more pronounced in cells with mutated IgVH genes. Thus, disturbed apoptosis in CLL is the net result of both protective and sensitizing aberrations. This delicate balance can be tipped via induction of Puma in a p53-dependent matter, the level of which may vary between groups of patients with a different tendency for disease progression.
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MESH Headings
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Apoptosis/genetics
- Apoptosis/physiology
- Apoptosis Regulatory Proteins
- Drug Resistance, Neoplasm
- Gene Expression Profiling/methods
- Gene Expression Regulation, Leukemic
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Tumor Suppressor Protein p53/drug effects
- Tumor Suppressor Protein p53/genetics
- Tumor Suppressor Protein p53/metabolism
- Up-Regulation/drug effects
- Vidarabine Phosphate/analogs & derivatives
- Vidarabine Phosphate/pharmacology
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Affiliation(s)
- W J M Mackus
- Department of Hematology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Morales AA, Olsson A, Celsing F, Osterborg A, Jondal M, Osorio LM. High expression of bfl-1 contributes to the apoptosis resistant phenotype in B-cell chronic lymphocytic leukemia. Int J Cancer 2005; 113:730-7. [PMID: 15499630 DOI: 10.1002/ijc.20614] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In order to identify regulatory genes involved in the development of an apoptosis-resistant phenotype in patients with chemotherapy refractory B-cell chronic lymphocytic leukemia (B-CLL) expression of apoptosis-regulating genes in B-CLL cells was quantified using cDNA arrays and RT-PCR. Data were obtained from and compared between 2 groups of B-CLL patients with either nonprogressive, indolent, previously untreated disease and with leukemic cells sensitive to in vitro fludarabine-induced apoptosis, referred to as sensitive B-CLL (sB-CLL) or with progressive, chemotherapy refractory disease and with leukemic cells resistant to in vitro fludarabine-induced apoptosis, referred to as resistant B-CLL (rB-CLL). By performing a supervised clustering of genes that most strongly discriminated between rB-CLL vs. sB-CLL a small group of genes was identified, where bfl-1 was the strongest discriminating gene (p < 0.05), with higher expression in rB-CLL. A group of apoptosis-regulating genes were modulated during induction of apoptosis by serum deprivation in vitro in a similar manner in all cases studied. However, bfl-1 was preferentially downregulated in sB-CLL as compared to rB-CLL (p < 0.05). We conclude that bfl-1 may be an important regulator of B-CLL apoptosis, which could contribute to disease progression and resistance to chemotherapy, and as such represent a future potential therapeutic target.
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MESH Headings
- Aged
- Aged, 80 and over
- Antineoplastic Agents/adverse effects
- Apoptosis/genetics
- Culture Media, Serum-Free/pharmacology
- DNA (Cytosine-5-)-Methyltransferases/antagonists & inhibitors
- Drug Resistance, Neoplasm
- Female
- Gene Expression Regulation, Leukemic
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Male
- Middle Aged
- Minor Histocompatibility Antigens
- Oligonucleotide Array Sequence Analysis
- Phenotype
- Proto-Oncogene Proteins c-bcl-2/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Tumor Cells, Cultured
- Up-Regulation
- Vidarabine/adverse effects
- Vidarabine/analogs & derivatives
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Affiliation(s)
- Alejo A Morales
- Microbiology and Tumor Biology Center, Karolinska Institutet, Stockholm, Sweden
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