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Feng J, Meng X. Histone modification and histone modification-targeted anti-cancer drugs in breast cancer: Fundamentals and beyond. Front Pharmacol 2022; 13:946811. [PMID: 36188615 PMCID: PMC9522521 DOI: 10.3389/fphar.2022.946811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/15/2022] [Indexed: 12/21/2022] Open
Abstract
Dysregulated epigenetic enzymes and resultant abnormal epigenetic modifications (EMs) have been suggested to be closely related to tumor occurrence and progression. Histone modifications (HMs) can assist in maintaining genome stability, DNA repair, transcription, and chromatin modulation within breast cancer (BC) cells. In addition, HMs are reversible, dynamic processes involving the associations of different enzymes with molecular compounds. Abnormal HMs (e.g. histone methylation and histone acetylation) have been identified to be tightly related to BC occurrence and development, even though their underlying mechanisms remain largely unclear. EMs are reversible, and as a result, epigenetic enzymes have aroused wide attention as anti-tumor therapeutic targets. At present, treatments to restore aberrant EMs within BC cells have entered preclinical or clinical trials. In addition, no existing studies have comprehensively analyzed aberrant HMs within BC cells; in addition, HM-targeting BC treatments remain to be further investigated. Histone and non-histone protein methylation is becoming an attractive anti-tumor epigenetic therapeutic target; such methylation-related enzyme inhibitors are under development at present. Consequently, the present work focuses on summarizing relevant studies on HMs related to BC and the possible mechanisms associated with abnormal HMs. Additionally, we also aim to analyze existing therapeutic agents together with those drugs approved and tested through pre-clinical and clinical trials, to assess their roles in HMs. Moreover, epi-drugs that target HMT inhibitors and HDAC inhibitors should be tested in preclinical and clinical studies for the treatment of BC. Epi-drugs that target histone methylation (HMT inhibitors) and histone acetylation (HDAC inhibitors) have now entered clinical trials or are approved by the US Food and Drug Administration (FDA). Therefore, the review covers the difficulties in applying HM-targeting treatments in clinics and proposes feasible approaches for overcoming such difficulties and promoting their use in treating BC cases.
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Jiang J, Wang HJ, Mou XZ, Zhang H, Chen Y, Hu ZM. Low Expression of KAT6B May Affect Prognosis in Hepatocellular Carcinoma. Technol Cancer Res Treat 2021; 20:15330338211033063. [PMID: 34464167 PMCID: PMC8411621 DOI: 10.1177/15330338211033063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Aims: Lysine acetyltransferase 6B (KAT6B), is a histone acetyltransferase
implicated to have a role in tumor suppression. However, the relationship
between KAT6B and hepatocellular carcinoma (HCC) is unclear. The purpose of
this study was to detect the expression of KAT6B in HCC tissues and analyze
its connection with the clinicopathological features of HCC. Methods: First, we performed immunohistochemical staining on 250 HCC tissues and 222
non-tumor liver tissues to examine the expression of KAT6B.Then the relation
between KAT6B expression and clinicopathological parameters was analyzed by
chi-square test, and the overall survival analysis was conducted by
Kaplan-Meier survival method. In addition, based on the Oncomine expression
array online and the UALCAN database, we compared KAT6B expression
differences between normal liver tissues and HCC tissues more broadly. Results: Compared with normal tissues, KAT6B expression was significantly lower in HCC
tissues. Low KAT6B expression was found to be related to gender, AFP level,
and tumor size. According to the online database, KAT6B expression was found
to be decreased in HCC tissues and high in normal tissues. Conclusions: Lower expression of KAT6B is associated with poor prognosis of HCC, and KAT6B
may be a potential tumor suppressor in liver cancer.
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Affiliation(s)
- Junjie Jiang
- Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.,Clinical Research Institute, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China
| | - Hui-Ju Wang
- Clinical Research Institute, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China
| | - Xiao-Zhou Mou
- Clinical Research Institute, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China
| | - Huanqing Zhang
- Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.,Clinical Research Institute, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China
| | - YiZhen Chen
- Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.,Clinical Research Institute, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China.,Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China
| | - Zhi-Ming Hu
- Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang Province, China
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3
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Wiesel-Motiuk N, Assaraf YG. The key roles of the lysine acetyltransferases KAT6A and KAT6B in physiology and pathology. Drug Resist Updat 2020; 53:100729. [PMID: 33130515 DOI: 10.1016/j.drup.2020.100729] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/21/2020] [Accepted: 08/28/2020] [Indexed: 12/14/2022]
Abstract
Histone modifications and more specifically ε-lysine acylations are key epigenetic regulators that control chromatin structure and gene transcription, thereby impacting on various important cellular processes and phenotypes. Furthermore, lysine acetylation of many non-histone proteins is involved in key cellular processes including transcription, DNA damage repair, metabolism, cellular proliferation, mitosis, signal transduction, protein folding, and autophagy. Acetylation affects protein functions through multiple mechanisms including regulation of protein stability, enzymatic activity, subcellular localization, crosstalk with other post-translational modifications as well as regulation of protein-protein and protein-DNA interactions. The paralogous lysine acetyltransferases KAT6A and KAT6B which belong to the MYST family of acetyltransferases, were first discovered approximately 25 years ago. KAT6 acetyltransferases acylate both histone H3 and non-histone proteins. In this respect, KAT6 acetyltransferases play key roles in regulation of transcription, various developmental processes, maintenance of hematopoietic and neural stem cells, regulation of hematopoietic cell differentiation, cell cycle progression as well as mitosis. In the current review, we discuss the physiological functions of the acetyltransferases KAT6A and KAT6B as well as their functions under pathological conditions of aberrant expression, leading to several developmental syndromes and cancer. Importantly, both upregulation and downregulation of KAT6 proteins was shown to play a role in cancer formation, progression, and therapy resistance, suggesting that they can act as oncogenes or tumor suppressors. We also describe reciprocal regulation of expression between KAT6 proteins and several microRNAs as well as their involvement in cancer formation, progression and resistance to therapy.
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Affiliation(s)
- Naama Wiesel-Motiuk
- The Fred Wyszkowski Cancer Research Laboratory, Dept. of Biology, Technion-Israel Institute of Technology, Haifa, 3200003, Israel
| | - Yehuda G Assaraf
- The Fred Wyszkowski Cancer Research Laboratory, Dept. of Biology, Technion-Israel Institute of Technology, Haifa, 3200003, Israel.
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4
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Rotunno M, Barajas R, Clyne M, Hoover E, Simonds NI, Lam TK, Mechanic LE, Goldstein AM, Gillanders EM. A Systematic Literature Review of Whole Exome and Genome Sequencing Population Studies of Genetic Susceptibility to Cancer. Cancer Epidemiol Biomarkers Prev 2020; 29:1519-1534. [PMID: 32467344 DOI: 10.1158/1055-9965.epi-19-1551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 03/17/2020] [Accepted: 05/13/2020] [Indexed: 01/03/2023] Open
Abstract
The application of next-generation sequencing (NGS) technologies in cancer research has accelerated the discovery of somatic mutations; however, progress in the identification of germline variation associated with cancer risk is less clear. We conducted a systematic literature review of cancer genetic susceptibility studies that used NGS technologies at an exome/genome-wide scale to obtain a fuller understanding of the research landscape to date and to inform future studies. The variability across studies on methodologies and reporting was considerable. Most studies sequenced few high-risk (mainly European) families, used a candidate analysis approach, and identified potential cancer-related germline variants or genes in a small fraction of the sequenced cancer cases. This review highlights the importance of establishing consensus on standards for the application and reporting of variants filtering strategies. It also describes the progress in the identification of cancer-related germline variation to date. These findings point to the untapped potential in conducting studies with appropriately sized and racially diverse families and populations, combining results across studies and expanding beyond a candidate analysis approach to advance the discovery of genetic variation that accounts for the unexplained cancer heritability.
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Affiliation(s)
- Melissa Rotunno
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland.
| | - Rolando Barajas
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Mindy Clyne
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Elise Hoover
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | | | - Tram Kim Lam
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Leah E Mechanic
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Alisa M Goldstein
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
| | - Elizabeth M Gillanders
- National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland
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5
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Abstract
Bromodomain-containing proteins are often part of chromatin-modifying complexes, and their activity can lead to altered expression of genes that drive cancer, inflammation and neurological disorders in humans. Bromodomain-PHD finger protein 1 (BRPF1) is part of the MOZ (monocytic leukemic zinc-finger protein) HAT (histone acetyltransferase) complex, which is associated with chromosomal translocations known to contribute to the development of acute myeloid leukemia (AML). BRPF1 contains a unique combination of chromatin reader domains including two plant homeodomain (PHD) fingers separated by a zinc knuckle (PZP domain), a bromodomain, and a proline-tryptophan-tryptophan-proline (PWWP) domain. BRPF1 is known to recruit the MOZ HAT complex to chromatin by recognizing acetylated lysine residues on the N-terminal histone tail region through its bromodomain. However, histone proteins can contain several acetylation modifications on their N-terminus, and it is unknown how additional marks influence bromodomain recruitment to chromatin. Here, we identify the BRPF1 bromodomain as a selective reader of di-acetyllysine modifications on histone H4. We used ITC assays to characterize the binding of di-acetylated histone ligands to the BRPF1 bromodomain and found that the domain binds preferentially to histone peptides H4K5acK8ac and H4K5acK12ac. Analytical ultracentrifugation (AUC) experiments revealed that the monomeric state of the BRPF1 bromodomain coordinates di-acetylated histone ligands. NMR chemical shift perturbation studies, along with binding and mutational analyses, revealed non-canonical regions of the bromodomain-binding pocket that are important for histone tail recognition. Together, our findings provide critical information on how the combinatorial action of post-translational modifications can modulate BRPF1 bromodomain binding and specificity.
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6
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Glentis S, Dimopoulos AC, Rouskas K, Ntritsos G, Evangelou E, Narod SA, Mes-Masson AM, Foulkes WD, Rivera B, Tonin PN, Ragoussis J, Dimas AS. Exome Sequencing in BRCA1- and BRCA2-Negative Greek Families Identifies MDM1 and NBEAL1 as Candidate Risk Genes for Hereditary Breast Cancer. Front Genet 2019; 10:1005. [PMID: 31681433 PMCID: PMC6813924 DOI: 10.3389/fgene.2019.01005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 09/20/2019] [Indexed: 12/30/2022] Open
Abstract
Approximately 10% of breast cancer (BC) cases are hereditary BC (HBC), with HBC most commonly encountered in the context of hereditary breast and ovarian cancer (HBOC) syndrome. Although thousands of loss-of-function (LoF) alleles in over 20 genes have been associated with HBC susceptibility, the genetic etiology of approximately 50% of cases remains unexplained, even when polygenic risk models are considered. We focused on one of the least-studied European populations and applied whole-exome sequencing (WES) to 52 individuals from 17 Greek HBOC families, in which at least one patient was negative for known HBC risk variants. Initial screening revealed pathogenic variants in known cancer genes, including BARD1:p.Trp91* detected in a cancer-free individual, and MEN1:p.Glu260Lys detected in a BC patient. Gene- and variant-based approaches were applied to exome data to identify candidate risk variants outside of known risk genes. Findings were verified in a collection of Canadian HBOC patients of European ancestry (FBRCAX), in an independent group of Canadian BC patients (CHUM-BC) and controls (CARTaGENE), as well as in individuals from The Cancer Genome Atlas (TCGA) and the UK Biobank (UKB). Rare LoF variants were uncovered in MDM1 and NBEAL1 in Greek and Canadian HBOC patients. We also report prioritized missense variants SETBP1:c.4129G > C and C7orf34:c.248C > T. These variants comprise promising candidates whose role in cancer pathogenicity needs to be explored further.
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Affiliation(s)
- Stavros Glentis
- Division of Molecular Biology and Genetics, Biomedical Sciences Research Center Al. Fleming, Vari, Greece
| | - Alexandros C Dimopoulos
- Division of Molecular Biology and Genetics, Biomedical Sciences Research Center Al. Fleming, Vari, Greece
| | - Konstantinos Rouskas
- Division of Molecular Biology and Genetics, Biomedical Sciences Research Center Al. Fleming, Vari, Greece
| | - George Ntritsos
- Department of Hygiene and Epidemiology, University of Ioannina Medical School, Ioannina, Greece
| | - Evangelos Evangelou
- Department of Hygiene and Epidemiology, University of Ioannina Medical School, Ioannina, Greece.,Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Steven A Narod
- Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.,Women's College Research Institute, Women's College Hospital, Toronto, ON, Canada
| | - Anne-Marie Mes-Masson
- Centre de recherche du Centre hospitalier de l'Université de Montréal and Institut du cancer de Montréal, Montreal, QC, Canada
| | - William D Foulkes
- Department of Oncology, McGill University, Montreal, QC, Canada.,Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, Canada.,Department of Medical Genetics, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Barbara Rivera
- Department of Oncology, McGill University, Montreal, QC, Canada.,Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, Canada
| | - Patricia N Tonin
- Department of Medicine, McGill University, Montreal, QC, Canada.,Department of Human Genetics, McGill University, Montreal, QC, Canada.,Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Jiannis Ragoussis
- Department of Oncology, McGill University, Montreal, QC, Canada.,McGill University and Genome Quebec Innovation Centre, Montreal, QC, Canada
| | - Antigone S Dimas
- Division of Molecular Biology and Genetics, Biomedical Sciences Research Center Al. Fleming, Vari, Greece
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7
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Hamdi Y, Boujemaa M, Ben Rekaya M, Ben Hamda C, Mighri N, El Benna H, Mejri N, Labidi S, Daoud N, Naouali C, Messaoud O, Chargui M, Ghedira K, Boubaker MS, Mrad R, Boussen H, Abdelhak S. Family specific genetic predisposition to breast cancer: results from Tunisian whole exome sequenced breast cancer cases. J Transl Med 2018; 16:158. [PMID: 29879995 PMCID: PMC5992876 DOI: 10.1186/s12967-018-1504-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/03/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND A family history of breast cancer has long been thought to indicate the presence of inherited genetic events that predispose to this disease. In North Africa, many specific epidemio-genetic characteristics have been observed in breast cancer families when compared to Western populations. Despite these specificities, the majority of breast cancer genetics studies performed in North Africa remain restricted to the investigation of the BRCA1 and BRCA2 genes. Thus, comprehensive data at a whole exome or whole genome level from local patients are lacking. METHODS A whole exome sequencing (WES) of seven breast cancer Tunisian families have been performed using a family-based approach. We focused our analysis on BC-TN-F001 family that included two affected members that have been sequenced using WES. Relevant variants identified in BC-TN-F001 have been confirmed using Sanger sequencing. Then, we conducted an integrative analysis by combining our results with those from other WES studies in order to figure out the genetic transmission model of the newly identified genes. Biological network construction and protein-protein interactions analyses have been performed to decipher the molecular mechanisms likely accounting for the role of these genes in breast cancer risk. RESULTS Sequencing, filtering strategies, and validation analysis have been achieved. For BC-TN-F001, no deleterious mutations have been identified on known breast cancer genes. However, 373 heterozygous, exonic and rare variants have been identified on other candidate genes. After applying several filters, 12 relevant high-risk variants have been selected. Our results showed that these variants seem to be inherited in a family specific model. This hypothesis has been confirmed following a thorough analysis of the reported WES studies. Enriched biological process and protein-protein interaction networks resulted in the identification of four novel breast cancer candidate genes namely MMS19, DNAH3, POLK and KATB6. CONCLUSIONS In this first WES application on Tunisian breast cancer patients, we highlighted the impact of next generation sequencing technologies in the identification of novel breast cancer candidate genes which may bring new insights into the biological mechanisms of breast carcinogenesis. Our findings showed that the breast cancer predisposition in non-BRCA families may be ethnic and/or family specific.
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Affiliation(s)
- Yosr Hamdi
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Maroua Boujemaa
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Mariem Ben Rekaya
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Cherif Ben Hamda
- Laboratory of Bioinformatics, Biomathematics and Biostatistics, LR16IPT09, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia
- Faculty of Sciences of Bizerte, Carthage University, Tunis, Tunisia
| | - Najah Mighri
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Houda El Benna
- Department of Medical Oncology, Abderrahmane Mami Hospital, Ariana, Tunisia
| | - Nesrine Mejri
- Department of Medical Oncology, Abderrahmane Mami Hospital, Ariana, Tunisia
| | - Soumaya Labidi
- Department of Medical Oncology, Abderrahmane Mami Hospital, Ariana, Tunisia
| | - Nouha Daoud
- Department of Medical Oncology, Abderrahmane Mami Hospital, Ariana, Tunisia
| | - Chokri Naouali
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Olfa Messaoud
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Mariem Chargui
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Kais Ghedira
- Laboratory of Bioinformatics, Biomathematics and Biostatistics, LR16IPT09, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Mohamed Samir Boubaker
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - Ridha Mrad
- Department of Human Genetics, Charles Nicolle Hospital, Tunis, Tunisia
| | - Hamouda Boussen
- Department of Medical Oncology, Abderrahmane Mami Hospital, Ariana, Tunisia
| | - Sonia Abdelhak
- Laboratory of Biomedical Genomics and Oncogenetics, LR16IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, 13, Place Pasteur-BP 74, 1002 Tunis, Tunisia
| | - the PEC Consortium
- Department of Medical Oncology, Abderrahmane Mami Hospital, Ariana, Tunisia
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8
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You L, Li L, Zou J, Yan K, Belle J, Nijnik A, Wang E, Yang XJ. BRPF1 is essential for development of fetal hematopoietic stem cells. J Clin Invest 2016; 126:3247-62. [PMID: 27500495 DOI: 10.1172/jci80711] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 06/16/2016] [Indexed: 12/21/2022] Open
Abstract
Hematopoietic stem cells (HSCs) serve as a life-long reservoir for all blood cell types and are clinically useful for a variety of HSC transplantation-based therapies. Understanding the role of chromatin organization and regulation in HSC homeostasis may provide important insights into HSC development. Bromodomain- and PHD finger-containing protein 1 (BRPF1) is a multivalent chromatin regulator that possesses 4 nucleosome-binding domains and activates 3 lysine acetyltransferases (KAT6A, KAT6B, and KAT7), suggesting that this protein has the potential to stimulate crosstalk between different chromatin modifications. Here, we investigated the function of BRPF1 in hematopoiesis by selectively deleting its gene in murine blood cells. Brpf1-deficient pups experienced early lethality due to acute bone marrow failure and aplastic anemia. The mutant bone marrow and fetal liver exhibited severe deficiency in HSCs and hematopoietic progenitors, along with elevated reactive oxygen species, senescence, and apoptosis. BRPF1 deficiency also reduced the expression of multipotency genes, including Slamf1, Mecom, Hoxa9, Hlf, Gfi1, Egr, and Gata3. Furthermore, BRPF1 was required for acetylation of histone H3 at lysine 23, a highly abundant but not well-characterized epigenetic mark. These results identify an essential role of the multivalent chromatin regulator BRPF1 in definitive hematopoiesis and illuminate a potentially new avenue for studying epigenetic networks that govern HSC ontogeny.
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9
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Yue L, Zhang Q, He L, Zhang M, Dong J, Zhao D, Ma H, Pan H, Zheng L. Genetic predisposition of six well-defined polymorphisms in HMGB1/RAGE pathway to breast cancer in a large Han Chinese population. J Cell Mol Med 2016; 20:1966-73. [PMID: 27241711 PMCID: PMC5020633 DOI: 10.1111/jcmm.12888] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/26/2016] [Indexed: 12/14/2022] Open
Abstract
Breast cancer constitutes an enormous burden in China. A strong familial clustering of breast cancer suggests a genetic component in its carcinogenesis. To examine the genetic predisposition of high mobility group box‐1/receptor for advanced glycation end products (HMGB1/RAGE) pathway to breast cancer, we genotyped six well‐defined polymorphisms in this pathway among 524 breast cancer patients and 518 cancer‐free controls from Heilongjiang province, China. There were no deviations from Hardy–Weinberg equilibrium for all polymorphisms. In single‐locus analysis, the frequency of rs1800624 polymorphism mutant A allele in RAGE gene was significantly higher in patients than in controls (24.52% versus 19.50%, P = 0.006), with the carriers of rs1800624‐A allele being 1.51 times more likely to develop breast cancer relative to those with rs1800624‐GG genotype after adjustment (95% confidence interval or CI: 1.17–1.94, P = 0.001). In HMGB1 gene, haplotype analysis did not reveal any significance, while in RAGE gene, haplotypes C‐T‐A and C‐A‐G (alleles in order of rs1800625, rs18006024, rs2070600) were significantly associated with an increased risk of breast cancer (adjusted OR = 2.72 and 10.35; 95% CI: 1.20–6.18 and 1.58–67.80; P = 0.017 and 0.015 respectively). In further genetic score analysis, per unit and quartile increments of unfavourable alleles were significantly associated with an increased risk of breast cancer after adjustment (odds ratio or OR = 1.20 and 1.26; 95% CI: 1.09–1.32 and 1.12–1.42; P < 0.001 and <0.001 respectively). Our findings altogether demonstrate a significant association between RAGE gene rs1800624 polymorphism and breast cancer risk, and more importantly a cumulative impact of multiple risk associated polymorphisms in HMGB1/RAGE pathway on breast carcinogenesis.
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Affiliation(s)
- Liling Yue
- Department of Biogenetics, Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Qibing Zhang
- Department of General Surgery, Daqing Oilfield General Hospital, Daqing, Heilongjiang, China
| | - Lan He
- Department of Mathematics, Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Minglong Zhang
- Department of Biogenetics, Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Jing Dong
- Department of Biogenetics, Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Dalong Zhao
- Clinical Laboratory, Qiqihar Jianhua Hospital, Qiqihar, Heilongjiang, China
| | - Hongxing Ma
- Clinical Laboratory, Daqing Oilfield General Hospital, Daqing, Heilongjiang, China
| | - Hongming Pan
- Department of Biochemistry, Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Lihong Zheng
- Department of Biogenetics, Qiqihar Medical University, Qiqihar, Heilongjiang, China.
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10
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Metastasis of Pregnancy-Associated Breast Cancer (Suspected to Be Hereditary Breast and Ovarian Cancer) to the Brain, Diagnosed at 18 Weeks' Gestation: A Case Report and Review of the Literature. Case Rep Obstet Gynecol 2016; 2016:9813253. [PMID: 26981296 PMCID: PMC4766327 DOI: 10.1155/2016/9813253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/13/2016] [Indexed: 11/23/2022] Open
Abstract
We report a case of pregnancy-associated breast cancer with metastasis to the brain, likely resulting from hereditary breast and ovarian cancer (HBOC). A 35-year-old woman (gravida 2, para 0-1-0-1) underwent a right mastectomy and right axillary dissection after a cesarean section at 30 years of age; her mother died at 47 years of age due to breast cancer. Histopathological examination indicated an invasive ductal carcinoma with triple-negative cancer (cancer stage 2B [pT3N0M0]). The patient refused adjuvant therapy because of the risk of infertility. After 4 years, she became pregnant naturally. At 18 weeks' gestation, she experienced aphasia and dyslexia due to brain metastasis. The pregnancy was terminated at 21 weeks' gestation after thorough counseling. Her family history, young-onset disease, and histopathological findings suggested HBOC. She declined genetic testing for BRCA1/2, though genetic counseling was provided. In cases of pregnancy-related breast cancer, consideration must be given to whether the pregnancy should be continued and to posttreatment fertility. HBOC should also be considered. Genetic counseling should be provided and the patient should be checked for the BRCA mutation, as it is meaningful for the future of any potential children. Genetic counseling should be provided even if the cancer is advanced or recurrent.
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Yan K, You L, Degerny C, Ghorbani M, Liu X, Chen L, Li L, Miao D, Yang XJ. The Chromatin Regulator BRPF3 Preferentially Activates the HBO1 Acetyltransferase but Is Dispensable for Mouse Development and Survival. J Biol Chem 2015; 291:2647-63. [PMID: 26677226 DOI: 10.1074/jbc.m115.703041] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Indexed: 12/12/2022] Open
Abstract
To interpret epigenetic information, chromatin readers utilize various protein domains for recognition of DNA and histone modifications. Some readers possess multidomains for modification recognition and are thus multivalent. Bromodomain- and plant homeodomain-linked finger-containing protein 3 (BRPF3) is such a chromatin reader, containing two plant homeodomain-linked fingers, one bromodomain and a PWWP domain. However, its molecular and biological functions remain to be investigated. Here, we report that endogenous BRPF3 preferentially forms a tetrameric complex with HBO1 (also known as KAT7) and two other subunits but not with related acetyltransferases such as MOZ, MORF, TIP60, and MOF (also known as KAT6A, KAT6B, KAT5, and KAT8, respectively). We have also characterized a mutant mouse strain with a lacZ reporter inserted at the Brpf3 locus. Systematic analysis of β-galactosidase activity revealed dynamic spatiotemporal expression of Brpf3 during mouse embryogenesis and high expression in the adult brain and testis. Brpf3 disruption, however, resulted in no obvious gross phenotypes. This is in stark contrast to Brpf1 and Brpf2, whose loss causes lethality at E9.5 and E15.5, respectively. In Brpf3-null mice and embryonic fibroblasts, RT-quantitative PCR uncovered no changes in levels of Brpf1 and Brpf2 transcripts, confirming no compensation from them. These results indicate that BRPF3 forms a functional tetrameric complex with HBO1 but is not required for mouse development and survival, thereby distinguishing BRPF3 from its paralogs, BRPF1 and BRPF2.
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Affiliation(s)
- Kezhi Yan
- From the Rosalind and Morris Goodman Cancer Research Center, Departments of Biochemistry and Medicine, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Linya You
- From the Rosalind and Morris Goodman Cancer Research Center, Medicine, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Cindy Degerny
- From the Rosalind and Morris Goodman Cancer Research Center
| | - Mohammad Ghorbani
- From the Rosalind and Morris Goodman Cancer Research Center, Medicine, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Xin Liu
- From the Rosalind and Morris Goodman Cancer Research Center
| | - Lulu Chen
- the State Key Laboratory of Reproductive Medicine, Research Center for Bone and Stem Cells, Department of Human Anatomy, Nanjing Medical University, Nanjing 210029, China, and
| | - Lin Li
- From the Rosalind and Morris Goodman Cancer Research Center, Medicine, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Dengshun Miao
- the State Key Laboratory of Reproductive Medicine, Research Center for Bone and Stem Cells, Department of Human Anatomy, Nanjing Medical University, Nanjing 210029, China, and
| | - Xiang-Jiao Yang
- From the Rosalind and Morris Goodman Cancer Research Center, Departments of Biochemistry and Medicine, McGill University, Montreal, Quebec H3A 1A3, Canada, the McGill University Health Center, Montreal, Quebec H3A 1A3, Canada
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Blein S, Barjhoux L, Damiola F, Dondon MG, Eon-Marchais S, Marcou M, Caron O, Lortholary A, Buecher B, Vennin P, Berthet P, Noguès C, Lasset C, Gauthier-Villars M, Mazoyer S, Stoppa-Lyonnet D, Andrieu N, Thomas G, Sinilnikova OM, Cox DG. Targeted Sequencing of the Mitochondrial Genome of Women at High Risk of Breast Cancer without Detectable Mutations in BRCA1/2. PLoS One 2015; 10:e0136192. [PMID: 26406445 PMCID: PMC4583250 DOI: 10.1371/journal.pone.0136192] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 07/31/2015] [Indexed: 12/30/2022] Open
Abstract
Breast Cancer is a complex multifactorial disease for which high-penetrance mutations have been identified. Approaches used to date have identified genomic features explaining about 50% of breast cancer heritability. A number of low- to medium penetrance alleles (per-allele odds ratio < 1.5 and 4.0, respectively) have been identified, suggesting that the remaining heritability is likely to be explained by the cumulative effect of such alleles and/or by rare high-penetrance alleles. Relatively few studies have specifically explored the mitochondrial genome for variants potentially implicated in breast cancer risk. For these reasons, we propose an exploration of the variability of the mitochondrial genome in individuals diagnosed with breast cancer, having a positive breast cancer family history but testing negative for BRCA1/2 pathogenic mutations. We sequenced the mitochondrial genome of 436 index breast cancer cases from the GENESIS study. As expected, no pathogenic genomic pattern common to the 436 women included in our study was observed. The mitochondrial genes MT-ATP6 and MT-CYB were observed to carry the highest number of variants in the study. The proteins encoded by these genes are involved in the structure of the mitochondrial respiration chain, and variants in these genes may impact reactive oxygen species production contributing to carcinogenesis. More functional and epidemiological studies are needed to further investigate to what extent variants identified may influence familial breast cancer risk.
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Affiliation(s)
- Sophie Blein
- INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France
| | - Laure Barjhoux
- INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France
| | | | - Francesca Damiola
- INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France
| | - Marie-Gabrielle Dondon
- Inserm, U900, Paris, France
- Institut Curie, Paris, France
- Mines ParisTech, Fontainebleau, France
| | - Séverine Eon-Marchais
- Inserm, U900, Paris, France
- Institut Curie, Paris, France
- Mines ParisTech, Fontainebleau, France
| | | | - Olivier Caron
- Consultation de Génétique, Département de Médecine, Institut de Cancérologie Gustave Roussy, Villejuif, France
| | | | - Bruno Buecher
- Institut Curie, Department of Tumour Biology, Paris, France
| | - Philippe Vennin
- Département de Cancérologie sénologique, CLCC Oscar Lambret, Lille, France
| | | | - Catherine Noguès
- Oncogénétique Clinique, Hôpital René Huguenin/Institut Curie, Saint-Cloud, France
| | - Christine Lasset
- Université Lyon 1, CNRS UMR5558, Lyon, France
- Unité de Prévention et d’Epidémiologie Génétique, Centre Léon Bérard, Lyon, France
| | - Marion Gauthier-Villars
- Consultation de Génétique, Département de Médecine, Institut de Cancérologie Gustave Roussy, Villejuif, France
| | - Sylvie Mazoyer
- INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France
| | - Dominique Stoppa-Lyonnet
- Consultation de Génétique, Département de Médecine, Institut de Cancérologie Gustave Roussy, Villejuif, France
- Institut Curie, INSERM U830, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, France
| | - Nadine Andrieu
- Inserm, U900, Paris, France
- Institut Curie, Paris, France
- Mines ParisTech, Fontainebleau, France
| | - Gilles Thomas
- Université Lyon 1, INCa-Synergie, Centre Léon Bérard, 28 rue Laennec, Lyon Cedex 08, France
| | - Olga M. Sinilnikova
- INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France
- Unité Mixte de Génétique Constitutionnelle des Cancers Fréquents, Hospices Civils de Lyon - Centre Léon Bérard, Lyon, France
| | - David G. Cox
- INSERM U1052, CNRS UMR5286, Université Lyon 1, Centre de Recherche en Cancérologie de Lyon, Lyon, France
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13
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Noh JM, Kim J, Cho DY, Choi DH, Park W, Huh SJ. Exome sequencing in a breast cancer family without BRCA mutation. Radiat Oncol J 2015; 33:149-54. [PMID: 26157685 PMCID: PMC4493427 DOI: 10.3857/roj.2015.33.2.149] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 01/08/2023] Open
Abstract
Purpose We performed exome sequencing in a breast cancer family without BRCA mutations. Materials and Methods A family that three sisters have a history of breast cancer was selected for analysis. There were no family members with breast cancer in the previous generation. Genetic testing for BRCA mutation was negative, even by the multiplex ligation-dependent probe amplification method. Two sisters with breast cancer were selected as affected members, while the mother of the sisters was a non-affected member. Whole exome sequencing was performed on the HiSeq 2000 platform with paired-end reads of 101 bp in the three members. Results We identified 19,436, 19,468, and 19,345 single-nucleotide polymorphisms (SNPs) in the coding regions. Among them, 8,759, 8,789, and 8,772 were non-synonymous SNPs, respectively. After filtering out 12,843 synonymous variations and 12,105 known variations with indels found in the dbSNP135 or 1000 Genomes Project database, we selected 73 variations in the samples from the affected sisters that did not occur in the sample from the unaffected mother. Using the Sorting Intolerant From Tolerant (SIFT), PolyPhen-2, and MutationTaster algorithms to predict amino acid substitutions, the XCR1, DLL1, TH, ACCS, SPPL3, CCNF, and SRL genes were risky among all three algorithms, while definite candidate genes could not be conclusively determined. Conclusion Using exome sequencing, we found 7 variants for a breast cancer family without BRCA mutations. Genetic evidence of disease association should be confirmed by future studies.
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Affiliation(s)
- Jae Myoung Noh
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jihun Kim
- LabGenomics Clinical Research Institute, LabGenomics, Seongnam, Korea
| | - Dae Yeon Cho
- LabGenomics Clinical Research Institute, LabGenomics, Seongnam, Korea
| | - Doo Ho Choi
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Won Park
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Seung Jae Huh
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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You L, Yan K, Zou J, Zhao H, Bertos NR, Park M, Wang E, Yang XJ. The chromatin regulator Brpf1 regulates embryo development and cell proliferation. J Biol Chem 2015; 290:11349-64. [PMID: 25773539 DOI: 10.1074/jbc.m115.643189] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Indexed: 12/22/2022] Open
Abstract
With hundreds of chromatin regulators identified in mammals, an emerging issue is how they modulate biological and pathological processes. BRPF1 (bromodomain- and PHD finger-containing protein 1) is a unique chromatin regulator possessing two PHD fingers, one bromodomain and a PWWP domain for recognizing multiple histone modifications. In addition, it binds to the acetyltransferases MOZ, MORF, and HBO1 (also known as KAT6A, KAT6B, and KAT7, respectively) to promote complex formation, restrict substrate specificity, and enhance enzymatic activity. We have recently showed that ablation of the mouse Brpf1 gene causes embryonic lethality at E9.5. Here we present systematic analyses of the mutant animals and demonstrate that the ablation leads to vascular defects in the placenta, yolk sac, and embryo proper, as well as abnormal neural tube closure. At the cellular level, Brpf1 loss inhibits proliferation of embryonic fibroblasts and hematopoietic progenitors. Molecularly, the loss reduces transcription of a ribosomal protein L10 (Rpl10)-like gene and the cell cycle inhibitor p27, and increases expression of the cell-cycle inhibitor p16 and a novel protein homologous to Scp3, a synaptonemal complex protein critical for chromosome association and embryo survival. These results uncover a crucial role of Brpf1 in controlling mouse embryo development and regulating cellular and gene expression programs.
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Affiliation(s)
- Linya You
- From the The Rosalind and Morris Goodman Cancer Research Center, Department of Medicine, and
| | - Kezhi Yan
- From the The Rosalind and Morris Goodman Cancer Research Center, Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3
| | - Jinfeng Zou
- National Research Council Canada, Montreal, Quebec H4P 2R2, and
| | - Hong Zhao
- From the The Rosalind and Morris Goodman Cancer Research Center
| | | | - Morag Park
- From the The Rosalind and Morris Goodman Cancer Research Center, Department of Medicine, and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, McGill University Health Center, Montreal, Quebec H3A 1A3, Canada
| | - Edwin Wang
- National Research Council Canada, Montreal, Quebec H4P 2R2, and
| | - Xiang-Jiao Yang
- From the The Rosalind and Morris Goodman Cancer Research Center, Department of Medicine, and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, McGill University Health Center, Montreal, Quebec H3A 1A3, Canada
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15
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The lysine acetyltransferase activator Brpf1 governs dentate gyrus development through neural stem cells and progenitors. PLoS Genet 2015; 11:e1005034. [PMID: 25757017 PMCID: PMC4355587 DOI: 10.1371/journal.pgen.1005034] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 01/28/2015] [Indexed: 12/18/2022] Open
Abstract
Lysine acetylation has recently emerged as an important post-translational modification in diverse organisms, but relatively little is known about its roles in mammalian development and stem cells. Bromodomain- and PHD finger-containing protein 1 (BRPF1) is a multidomain histone binder and a master activator of three lysine acetyltransferases, MOZ, MORF and HBO1, which are also known as KAT6A, KAT6B and KAT7, respectively. While the MOZ and MORF genes are rearranged in leukemia, the MORF gene is also mutated in prostate and other cancers and in four genetic disorders with intellectual disability. Here we show that forebrain-specific inactivation of the mouse Brpf1 gene causes hypoplasia in the dentate gyrus, including underdevelopment of the suprapyramidal blade and complete loss of the infrapyramidal blade. We trace the developmental origin to compromised Sox2+ neural stem cells and Tbr2+ intermediate neuronal progenitors. We further demonstrate that Brpf1 loss deregulates neuronal migration, cell cycle progression and transcriptional control, thereby causing abnormal morphogenesis of the hippocampus. These results link histone binding and acetylation control to hippocampus development and identify an important epigenetic regulator for patterning the dentate gyrus, a brain structure critical for learning, memory and adult neurogenesis. Lysine acetylation refers to addition of the acetyl group to lysine residues after protein synthesis. Little is known about how this modification plays a role in the brain and neural stem cells. It is catalyzed by a group of enzymes known as lysine acetyltransferases. A novel epigenetic regulator called BRPF1 acts as a master activator of three different lysine acetyltransferases and also contains multiple structural domains for histone binding. In this study, we show that forebrain-specific inactivation of the mouse Brpf1 gene causes abnormal development of the dentate gyrus, a key component of the hippocampus. We trace the developmental origin to compromised neural stem cells and progenitors, and demonstrate that Brpf1 loss deregulates neuronal migration and cell cycle progression during development of the dentate gyrus. This is the first report on an epigenetic regulator whose loss has such a profound impact on the hippocampus, especially the dentate gyrus, a brain structure critical for learning, memory and adult neurogenesis.
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Wen H, Kim YC, Snyder C, Xiao F, Fleissner EA, Becirovic D, Luo J, Downs B, Sherman S, Cowan KH, Lynch HT, Wang SM. Family-specific, novel, deleterious germline variants provide a rich resource to identify genetic predispositions for BRCAx familial breast cancer. BMC Cancer 2014; 14:470. [PMID: 24969172 PMCID: PMC4083142 DOI: 10.1186/1471-2407-14-470] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 06/20/2014] [Indexed: 12/02/2022] Open
Abstract
Background Genetic predisposition is the primary risk factor for familial breast cancer. For the majority of familial breast cancer, however, the genetic predispositions remain unknown. All newly identified predispositions occur rarely in disease population, and the unknown genetic predispositions are estimated to reach up to total thousands. Family unit is the basic structure of genetics. Because it is an autosomal dominant disease, individuals with a history of familial breast cancer must carry the same genetic predisposition across generations. Therefore, focusing on the cases in lineages of familial breast cancer, rather than pooled cases in disease population, is expected to provide high probability to identify the genetic predisposition for each family. Methods In this study, we tested genetic predispositions by analyzing the family-specific variants in familial breast cancer. Using exome sequencing, we analyzed three families and 22 probands with BRCAx (BRCA-negative) familial breast cancer. Results We observed the presence of family-specific, novel, deleterious germline variants in each family. Of the germline variants identified, many were shared between the disease-affected family members of the same family but not found in different families, which have their own specific variants. Certain variants are putative deleterious genetic predispositions damaging functionally important genes involved in DNA replication and damaging repair, tumor suppression, signal transduction, and phosphorylation. Conclusions Our study demonstrates that the predispositions for many BRCAx familial breast cancer families can lie in each disease family. The application of a family-focused approach has the potential to detect many new predispositions.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Henry T Lynch
- Department of Genetics, Cell Biology and Anatomy, College of Medicine, University of Nebraska Medical Center, 986805 Nebraska Medical Center, Omaha, NE 68198, USA.
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