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Wang X, Bai F, Liu X, Peng B, Xu X, Zhang H, Fu L, Zhu WG, Wang B, Pei XH. GATA3 functions downstream of BRCA1 to promote DNA damage repair and suppress dedifferentiation in breast cancer. BMC Biol 2024; 22:85. [PMID: 38627785 PMCID: PMC11020915 DOI: 10.1186/s12915-024-01881-6] [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: 03/30/2023] [Accepted: 04/04/2024] [Indexed: 04/19/2024] Open
Abstract
BACKGROUND Inadequate DNA damage repair promotes aberrant differentiation of mammary epithelial cells. Mammary luminal cell fate is mainly determined by a few transcription factors including GATA3. We previously reported that GATA3 functions downstream of BRCA1 to suppress aberrant differentiation in breast cancer. How GATA3 impacts DNA damage repair preventing aberrant cell differentiation in breast cancer remains elusive. We previously demonstrated that loss of p18, a cell cycle inhibitor, in mice induces luminal-type mammary tumors, whereas depletion of either Brca1 or Gata3 in p18 null mice leads to basal-like breast cancers (BLBCs) with activation of epithelial-mesenchymal transition (EMT). We took advantage of these mutant mice to examine the role of Gata3 as well as the interaction of Gata3 and Brca1 in DNA damage repair in mammary tumorigenesis. RESULTS Depletion of Gata3, like that of Brca1, promoted DNA damage accumulation in breast cancer cells in vitro and in basal-like breast cancers in vivo. Reconstitution of Gata3 improved DNA damage repair in Brca1-deficient mammary tumorigenesis. Overexpression of GATA3 promoted homologous recombination (HR)-mediated DNA damage repair and restored HR efficiency of BRCA1-deficient cells. Depletion of Gata3 sensitized tumor cells to PARP inhibitor (PARPi), and reconstitution of Gata3 enhanced resistance of Brca1-deficient tumor cells to PARP inhibitor. CONCLUSIONS These results demonstrate that Gata3 functions downstream of BRCA1 to promote DNA damage repair and suppress dedifferentiation in mammary tumorigenesis and progression. Our findings suggest that PARP inhibitors are effective for the treatment of GATA3-deficient BLBCs.
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Affiliation(s)
- Xuejie Wang
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Medical School, Shenzhen, 518060, China
| | - Feng Bai
- Department of Pathology, Shenzhen University Medical School, Shenzhen, 518060, China
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL, 33136, USA
| | - Xiong Liu
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Medical School, Shenzhen, 518060, China
| | - Bin Peng
- Guangdong Key Laboratory for Genome Stability & Disease Prevention and International Cancer Center and Marshall Laboratory of Biomedical Engineering, Shenzhen University Medical School, Shenzhen, 518060, China
| | - Xingzhi Xu
- Guangdong Key Laboratory for Genome Stability & Disease Prevention and International Cancer Center and Marshall Laboratory of Biomedical Engineering, Shenzhen University Medical School, Shenzhen, 518060, China
| | - Hongquan Zhang
- Program for Cancer and Cell Biology, Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Li Fu
- Department of Pharmacology, Shenzhen University Medical School, Shenzhen, 518039, China
| | - Wei-Guo Zhu
- Department of Biochemistry and Molecular Biology, International Cancer Center, Shenzhen University Medical School, Shenzhen, 518060, China
| | - Bin Wang
- Department of General Surgery, Shenzhen Children's Hospital, Shenzhen, 518038, China.
| | - Xin-Hai Pei
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Medical School, Shenzhen, 518060, China.
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL, 33136, USA.
- Department of Anatomy and Histology, Shenzhen University Medical School, Shenzhen, 518060, China.
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Liu X, Bai F, Wang Y, Wang C, Chan HL, Zheng C, Fang J, Zhu WG, Pei XH. Loss of function of GATA3 regulates FRA1 and c-FOS to activate EMT and promote mammary tumorigenesis and metastasis. Cell Death Dis 2023; 14:370. [PMID: 37353480 PMCID: PMC10290069 DOI: 10.1038/s41419-023-05888-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 06/08/2023] [Accepted: 06/14/2023] [Indexed: 06/25/2023]
Abstract
Basal-like breast cancers (BLBCs) are among the most aggressive cancers, partly due to their enrichment of cancer stem cells (CSCs). Breast CSCs can be generated from luminal-type cancer cells via epithelial-mesenchymal transition (EMT). GATA3 maintains luminal cell fate, and its expression is lost or reduced in BLBCs. However, deletion of Gata3 in mice or cells results in early lethality or proliferative defects. It is unknown how loss-of-function of GATA3 regulates EMT and CSCs in breast cancer. We report here that haploid loss of Gata3 in mice lacking p18Ink4c, a cell cycle inhibitor, up-regulates Fra1, an AP-1 family protein that promotes mesenchymal traits, and downregulates c-Fos, another AP-1 family protein that maintains epithelial fate, leading to activation of EMT and promotion of mammary tumor initiation and metastasis. Depletion of Gata3 in luminal tumor cells similarly regulates Fra1 and c-Fos in activation of EMT. GATA3 binds to FOSL1 (encoding FRA1) and FOS (encoding c-FOS) loci to repress FOSL1 and activate FOS transcription. Deletion of Fra1 or reconstitution of Gata3, but not reconstitution of c-Fos, in Gata3 deficient tumor cells inhibits EMT, preventing tumorigenesis and/or metastasis. In human breast cancers, GATA3 expression is negatively correlated with FRA1 and positively correlated with c-FOS. Low GATA3 and FOS, but high FOSL1, are characteristics of BLBCs. Together, these data provide the first genetic evidence indicating that loss of function of GATA3 in mammary tumor cells activates FOSL1 to promote mesenchymal traits and CSC function, while concurrently repressing FOS to lose epithelial features. We demonstrate that FRA1 is required for the activation of EMT in GATA3 deficient tumorigenesis and metastasis.
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Affiliation(s)
- Xiong Liu
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Health Science Center, Shenzhen, 518060, China
| | - Feng Bai
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Health Science Center, Shenzhen, 518060, China.
- Department of Pathology, Shenzhen University Health Science Center, Shenzhen, 518060, China.
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL, 33136, USA.
| | - Yuchan Wang
- Gansu Dian Medical Laboratory, Lanzhou, 730000, China
| | - Chuying Wang
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL, 33136, USA
- The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, China
| | - Ho Lam Chan
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL, 33136, USA
| | - Chenglong Zheng
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Health Science Center, Shenzhen, 518060, China
| | - Jian Fang
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Health Science Center, Shenzhen, 518060, China
| | - Wei-Guo Zhu
- Department of Biochemistry and Molecular Biology, International Cancer Center, Shenzhen University Health Science Center, Shenzhen, 518060, China
| | - Xin-Hai Pei
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, The First Affiliated Hospital, Shenzhen University Health Science Center, Shenzhen, 518060, China.
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL, 33136, USA.
- Department of Anatomy and Histology, Shenzhen University Health Science Center, Shenzhen, 518060, China.
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Cooles FAH, Tarn J, Lendrem DW, Naamane N, Lin CM, Millar B, Maney NJ, Anderson AE, Thalayasingam N, Diboll J, Bondet V, Duffy D, Barnes MR, Smith GR, Ng S, Watson D, Henkin R, Cope AP, Reynard LN, Pratt AG, Isaacs JD. Interferon-α-mediated therapeutic resistance in early rheumatoid arthritis implicates epigenetic reprogramming. Ann Rheum Dis 2022; 81:1214-1223. [PMID: 35680389 PMCID: PMC9380486 DOI: 10.1136/annrheumdis-2022-222370] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/23/2022] [Indexed: 11/09/2022]
Abstract
OBJECTIVES An interferon (IFN) gene signature (IGS) is present in approximately 50% of early, treatment naive rheumatoid arthritis (eRA) patients where it has been shown to negatively impact initial response to treatment. We wished to validate this effect and explore potential mechanisms of action. METHODS In a multicentre inception cohort of eRA patients (n=191), we examined the whole blood IGS (MxA, IFI44L, OAS1, IFI6, ISG15) with reference to circulating IFN proteins, clinical outcomes and epigenetic influences on circulating CD19+ B and CD4+ T lymphocytes. RESULTS We reproduced our previous findings demonstrating a raised baseline IGS. We additionally showed, for the first time, that the IGS in eRA reflects circulating IFN-α protein. Paired longitudinal analysis demonstrated a significant reduction between baseline and 6-month IGS and IFN-α levels (p<0.0001 for both). Despite this fall, a raised baseline IGS predicted worse 6-month clinical outcomes such as increased disease activity score (DAS-28, p=0.025) and lower likelihood of a good EULAR clinical response (p=0.034), which was independent of other conventional predictors of disease activity and clinical response. Molecular analysis of CD4+ T cells and CD19+ B cells demonstrated differentially methylated CPG sites and dysregulated expression of disease relevant genes, including PARP9, STAT1, and EPSTI1, associated with baseline IGS/IFNα levels. Differentially methylated CPG sites implicated altered transcription factor binding in B cells (GATA3, ETSI, NFATC2, EZH2) and T cells (p300, HIF1α). CONCLUSIONS Our data suggest that, in eRA, IFN-α can cause a sustained, epigenetically mediated, pathogenic increase in lymphocyte activation and proliferation, and that the IGS is, therefore, a robust prognostic biomarker. Its persistent harmful effects provide a rationale for the initial therapeutic targeting of IFN-α in selected patients with eRA.
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Affiliation(s)
- Faye A H Cooles
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Jessica Tarn
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Dennis W Lendrem
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Najib Naamane
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Chung Ma Lin
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Ben Millar
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Nicola J Maney
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Amy E Anderson
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Nishanthi Thalayasingam
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Julie Diboll
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Vincent Bondet
- Laboratory of Dendritic Cell Immunobiology, Institut Pasteur, Paris, France
| | - Darragh Duffy
- Laboratory of Dendritic Cell Immunobiology, Institut Pasteur, Paris, France
- Center for Translational Research, Institut Pasteur, Paris, France
| | - Michael R Barnes
- Centre for Translational Bioinformatics, William Harvey Research Institute, London, UK
| | - Graham R Smith
- Bioinformatics Support Unit, Newcastle University Faculty of Medical Sciences, Newcastle Upon Tyne, UK
| | - Sandra Ng
- Centre for Translational Bioinformatics, William Harvey Research Institute, London, UK
| | - David Watson
- Department of Statistical Science, University College London, London, UK
| | - Rafael Henkin
- Centre for Translational Bioinformatics, William Harvey Research Institute, London, UK
| | - Andrew P Cope
- Academic Department of Rheumatology, King's College London, London, UK
| | - Louise N Reynard
- Newcastle University Biosciences Institute, Newcastle University, Newcastle Upon Tyne, UK
| | - Arthur G Pratt
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
- Musculoskeletal Research Group, The Freeman Hospital, Newcastle Upon Tyne, UK
| | - John D Isaacs
- Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK
- Musculoskeletal Research Group, The Freeman Hospital, Newcastle Upon Tyne, UK
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Bai F, Zheng C, Liu X, Chan HL, Liu S, Ma J, Ren S, Zhu WG, Pei XH. Loss of function of GATA3 induces basal-like mammary tumors. Am J Cancer Res 2022; 12:720-733. [PMID: 34976209 PMCID: PMC8692904 DOI: 10.7150/thno.65796] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/13/2021] [Indexed: 11/25/2022] Open
Abstract
Purpose: GATA3 is a transcription factor essential for mammary luminal epithelial cell differentiation. Expression of GATA3 is absent or significantly reduced in basal-like breast cancers. Gata3 loss-of-function impairs cell proliferation, making it difficult to investigate the role of GATA3 deficiency in vivo. We previously demonstrated that CDK inhibitor p18INK4c (p18) is a downstream target of GATA3 and restrains mammary epithelial cell proliferation and tumorigenesis. Whether and how loss-of-function of GATA3 results in basal-like breast cancers remains elusive. Methods: We generated mutant mouse strains with heterozygous germline deletion of Gata3 in p18 deficient backgrounds and developed a Gata3 depleted mammary tumor model system to determine the role of Gata3 loss in controlling cell proliferation and aberrant differentiation in mammary tumor development and progression. Results: Haploid loss of Gata3 reduced mammary epithelial cell proliferation with induction of p18, impaired luminal differentiation, and promoted basal differentiation in mammary glands. p18 deficiency induced luminal type mammary tumors and rescued the proliferative defect caused by haploid loss of Gata3. Haploid loss of Gata3 accelerated p18 deficient mammary tumor development and changed the properties of these tumors, resulting in their malignant and luminal-to-basal transformation. Expression of Gata3 negatively correlated with basal differentiation markers in MMTV-PyMT mammary tumor cells. Depletion of Gata3 in luminal tumor cells also reduced cell proliferation with induction of p18 and promoted basal differentiation. We confirmed that expression of GATA3 and basal markers are inversely correlated in human basal-like breast cancers. Conclusions: This study provides the first genetic evidence demonstrating that loss-of-function of GATA3 directly induces basal-like breast cancer. Our finding suggests that basal-like breast cancer may also originate from luminal type cancer.
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Bai F, Zhang LH, Liu X, Wang C, Zheng C, Sun J, Li M, Zhu WG, Pei XH. GATA3 functions downstream of BRCA1 to suppress EMT in breast cancer. Theranostics 2021; 11:8218-8233. [PMID: 34373738 PMCID: PMC8344017 DOI: 10.7150/thno.59280] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 07/05/2021] [Indexed: 02/06/2023] Open
Abstract
Purpose: Functional loss of BRCA1 is associated with poorly differentiated and metastatic breast cancers that are enriched with cancer stem cells (CSCs). CSCs can be generated from carcinoma cells through an epithelial-mesenchymal transition (EMT) program. We and others have previously demonstrated that BRCA1 suppresses EMT and regulates the expression of multiple EMT-related transcription factors. However, the downstream mediators of BRCA1 function in EMT suppression remain elusive. Methods: Depletion of BRCA1 or GATA3 activates p18INK4C , a cell cycle inhibitor which inhibits mammary epithelial cell proliferation. We have therefore created genetically engineered mice with Brca1 or Gata3 loss in addition to deletion of p18INK4C , to rescue proliferative defects caused by deficiency of Brca1 or Gata3. By using these mutant mice along with human BRCA1 deficient as well as proficient breast cancer tissues and cells, we investigated and compared the role of Brca1 and Gata3 loss in the activation of EMT in breast cancers. Results: We discovered that BRCA1 and GATA3 expressions were positively correlated in human breast cancer. Depletion of BRCA1 stimulated methylation of GATA3 promoter thereby repressing GATA3 transcription. We developed Brca1 and Gata3 deficient mouse system. We found that Gata3 deficiency in mice induced poorly-differentiated mammary tumors with the activation of EMT and promoted tumor initiating and metastatic potential. Gata3 deficient mammary tumors phenocopied Brca1 deficient tumors in the induction of EMT under the same genetic background. Reconstitution of Gata3 in Brca1-deficient tumor cells activated mesenchymal-epithelial transition, suppressing tumor initiation and metastasis. Conclusions: Our finding, for the first time, demonstrates that GATA3 functions downstream of BRCA1 to suppress EMT in controlling mammary tumorigenesis and metastasis.
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Affiliation(s)
- Feng Bai
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen 518060, China
- Department of Pathology, Shenzhen University Health Science Center, Shenzhen 518060, China
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL 33136, USA
| | - Li-Han Zhang
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL 33136, USA
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
- The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan 450008, China
| | - Xiong Liu
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen 518060, China
- Department of Anatomy and Histology, Shenzhen University Health Science Center, Shenzhen 518060, China
| | - Chuying Wang
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL 33136, USA
- The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, China
| | - Chenglong Zheng
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen 518060, China
- Department of Anatomy and Histology, Shenzhen University Health Science Center, Shenzhen 518060, China
| | - Jianping Sun
- Department of Mathematics and Statistics, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Min Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Wei-Guo Zhu
- Department of Biochemistry and Molecular Biology, International Cancer Center, Shenzhen University Health Science Center, Shenzhen 518060, China
| | - Xin-Hai Pei
- Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, International Cancer Center, Marshall Laboratory of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen 518060, China
- Dewitt Daughtry Family Department of Surgery, University of Miami, Miami, FL 33136, USA
- Department of Anatomy and Histology, Shenzhen University Health Science Center, Shenzhen 518060, China
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Akay M, Hite J, Avci NG, Fan Y, Akay Y, Lu G, Zhu JJ. Drug Screening of Human GBM Spheroids in Brain Cancer Chip. Sci Rep 2018; 8:15423. [PMID: 30337660 PMCID: PMC6194126 DOI: 10.1038/s41598-018-33641-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 10/03/2018] [Indexed: 12/14/2022] Open
Abstract
Glioblastoma multiforme (GBM), an extremely invasive and high-grade (grade IV) glioma, is the most common and aggressive form of brain cancer. It has a poor prognosis, with a median overall survival of only 11 months in the general GBM population and 14.6 to 21 months in clinical trial participants with standard GBM therapies, including maximum safe craniotomy, adjuvant radiation, and chemotherapies. Therefore, new approaches for developing effective treatments, such as a tool for assessing tumor cell drug response before drug treatments are administered, are urgently needed to improve patient survival. To address this issue, we developed an improved brain cancer chip with a diffusion prevention mechanism that blocks drugs crossing from one channel to another. In the current study, we demonstrate that the chip has the ability to culture 3D spheroids from patient tumor specimen-derived GBM cells obtained from three GBM patients. Two clinical drugs used to treat GBM, temozolomide (TMZ) and bevacizumab (Avastin, BEV), were applied and a range of relative concentrations was generated by the microfluidic channels in the brain cancer chip. The results showed that TMZ works more effectively when used in combination with BEV compared to TMZ alone. We believe that this low-cost brain cancer chip could be further developed to generate optimal combination of chemotherapy drugs tailored to individual GBM patients.
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Affiliation(s)
- Metin Akay
- Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd, Houston, TX, USA.
| | - John Hite
- Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd, Houston, TX, USA
| | - Naze Gul Avci
- Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd, Houston, TX, USA
| | - Yantao Fan
- Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd, Houston, TX, USA
| | - Yasemin Akay
- Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd, Houston, TX, USA
| | - Guangrong Lu
- Mischer Neuroscience Associates and the Vivian L. Smith Department of Neurosurgery University of Texas Health Science Center in Houston, UTHealth and Memorial Hermann, 6400 Fannin St. Suite 2800, Houston, TX, 77030, USA
| | - Jay-Jiguang Zhu
- Mischer Neuroscience Associates and the Vivian L. Smith Department of Neurosurgery University of Texas Health Science Center in Houston, UTHealth and Memorial Hermann, 6400 Fannin St. Suite 2800, Houston, TX, 77030, USA
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Styles CT, Bazot Q, Parker GA, White RE, Paschos K, Allday MJ. EBV epigenetically suppresses the B cell-to-plasma cell differentiation pathway while establishing long-term latency. PLoS Biol 2017; 15:e2001992. [PMID: 28771465 PMCID: PMC5542390 DOI: 10.1371/journal.pbio.2001992] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 07/10/2017] [Indexed: 11/29/2022] Open
Abstract
Mature human B cells infected by Epstein-Barr virus (EBV) become activated, grow, and proliferate. If the cells are infected ex vivo, they are transformed into continuously proliferating lymphoblastoid cell lines (LCLs) that carry EBV DNA as extra-chromosomal episomes, express 9 latency-associated EBV proteins, and phenotypically resemble antigen-activated B-blasts. In vivo similar B-blasts can differentiate to become memory B cells (MBC), in which EBV persistence is established. Three related latency-associated viral proteins EBNA3A, EBNA3B, and EBNA3C are transcription factors that regulate a multitude of cellular genes. EBNA3B is not necessary to establish LCLs, but EBNA3A and EBNA3C are required to sustain proliferation, in part, by repressing the expression of tumour suppressor genes. Here we show, using EBV-recombinants in which both EBNA3A and EBNA3C can be conditionally inactivated or using virus completely lacking the EBNA3 gene locus, that-after a phase of rapid proliferation-infected primary B cells express elevated levels of factors associated with plasma cell (PC) differentiation. These include the cyclin-dependent kinase inhibitor (CDKI) p18INK4c, the master transcriptional regulator of PC differentiation B lymphocyte-induced maturation protein-1 (BLIMP-1), and the cell surface antigens CD38 and CD138/Syndecan-1. Chromatin immunoprecipitation sequencing (ChIP-seq) and chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) indicate that in LCLs inhibition of CDKN2C (p18INK4c) and PRDM1 (BLIMP-1) transcription results from direct binding of EBNA3A and EBNA3C to regulatory elements at these loci, producing stable reprogramming. Consistent with the binding of EBNA3A and/or EBNA3C leading to irreversible epigenetic changes, cells become committed to a B-blast fate <12 days post-infection and are unable to de-repress p18INK4c or BLIMP-1-in either newly infected cells or conditional LCLs-by inactivating EBNA3A and EBNA3C. In vitro, about 20 days after infection with EBV lacking functional EBNA3A and EBNA3C, cells develop a PC-like phenotype. Together, these data suggest that EBNA3A and EBNA3C have evolved to prevent differentiation to PCs after infection by EBV, thus favouring long-term latency in MBC and asymptomatic persistence.
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Affiliation(s)
- Christine T. Styles
- Molecular Virology, Department of Medicine, Imperial College London, London, United Kingdom
| | - Quentin Bazot
- Molecular Virology, Department of Medicine, Imperial College London, London, United Kingdom
| | - Gillian A. Parker
- Molecular Virology, Department of Medicine, Imperial College London, London, United Kingdom
| | - Robert E. White
- Molecular Virology, Department of Medicine, Imperial College London, London, United Kingdom
| | - Kostas Paschos
- Molecular Virology, Department of Medicine, Imperial College London, London, United Kingdom
| | - Martin J. Allday
- Molecular Virology, Department of Medicine, Imperial College London, London, United Kingdom
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The Regulatory Capacity of Bivalent Genes-A Theoretical Approach. Int J Mol Sci 2017; 18:ijms18051069. [PMID: 28513551 PMCID: PMC5454979 DOI: 10.3390/ijms18051069] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 02/07/2023] Open
Abstract
Bivalent genes are frequently associated with developmental and lineage specification processes. Resolving their bivalency enables fast changes in their expression, which potentially can trigger cell fate decisions. Here, we provide a theoretical model of bivalency that allows for predictions on the occurrence, stability and regulatory capacity of this prominent modification state. We suggest that bivalency enables balanced gene expression heterogeneity that constitutes a prerequisite of robust lineage priming in somatic stem cells. Moreover, we demonstrate that interactions between the histone and DNA methylation machineries together with the proliferation activity control the stability of the bivalent state and can turn it into an unmodified state. We suggest that deregulation of these interactions underlies cell transformation processes as associated with acute myeloid leukemia (AML) and provide a model of AML blast formation following deregulation of the Ten-eleven Translocation (TET) pathway.
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