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Tribe AKW, Peng L, Teesdale-Spittle PH, McConnell MJ. BCL6 is a context-dependent mediator of the glioblastoma response to irradiation therapy. Int J Biol Macromol 2024; 270:131782. [PMID: 38734343 DOI: 10.1016/j.ijbiomac.2024.131782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 12/14/2023] [Accepted: 04/21/2024] [Indexed: 05/13/2024]
Abstract
Glioblastoma is a rapidly fatal brain cancer that does not respond to therapy. Previous research showed that the transcriptional repressor protein BCL6 is upregulated by chemo and radiotherapy in glioblastoma, and inhibition of BCL6 enhances the effectiveness of these therapies. Therefore, BCL6 is a promising target to improve the efficacy of current glioblastoma treatment. BCL6 acts as a transcriptional repressor in germinal centre B cells and as an oncogene in lymphoma and other cancers. However, in glioblastoma, BCL6 induced by therapy may not be able to repress transcription. Using a BCL6 inhibitor, the whole proteome response to irradiation was compared with and without BCL6 activity. Acute high dose irradiation caused BCL6 to switch from repressing the DNA damage response to promoting stress response signalling. Rapid immunoprecipitation mass spectrometry of endogenous proteins (RIME) enabled comparison of BCL6 partner proteins between untreated and irradiated glioblastoma cells. BCL6 was associated with transcriptional coregulators in untreated glioblastoma including the known partner NCOR2. However, this association was lost in response to acute irradiation, where BCL6 unexpectedly associated with synaptic and plasma membrane proteins. These results reveal the activity of BCL6 under therapy-induced stress is context-dependent, and potentially altered by the intensity of that stress.
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Affiliation(s)
- Anna K W Tribe
- School of Biological Sciences, Te Herenga Waka Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand.
| | - Lifeng Peng
- School of Biological Sciences, Te Herenga Waka Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand.
| | - Paul H Teesdale-Spittle
- School of Biological Sciences, Te Herenga Waka Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand.
| | - Melanie J McConnell
- School of Biological Sciences, Te Herenga Waka Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand.
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2
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Sun P, Cui M, Jing J, Kong F, Wang S, Tang L, Leng J, Chen K. Deciphering the molecular and cellular atlas of immune cells in septic patients with different bacterial infections. J Transl Med 2023; 21:777. [PMID: 37919720 PMCID: PMC10621118 DOI: 10.1186/s12967-023-04631-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 10/14/2023] [Indexed: 11/04/2023] Open
Abstract
BACKGROUND Sepsis is a life-threatening organ dysfunction caused by abnormal immune responses to various, predominantly bacterial, infections. Different bacterial infections lead to substantial variation in disease manifestation and therapeutic strategies. However, the underlying cellular heterogeneity and mechanisms involved remain poorly understood. METHODS Multiple bulk transcriptome datasets from septic patients with 12 types of bacterial infections were integrated to identify signature genes for each infection. Signature genes were mapped onto an integrated large single-cell RNA (scRNA) dataset from septic patients, to identify subsets of cells associated with different sepsis types, and multiple omics datasets were combined to reveal the underlying molecular mechanisms. In addition, an scRNA dataset and spatial transcriptome data were used to identify signaling pathways in sepsis-related cells. Finally, molecular screening, optimization, and de novo design were conducted to identify potential targeted drugs and compounds. RESULTS We elucidated the cellular heterogeneity among septic patients with different bacterial infections. In Escherichia coli (E. coli) sepsis, 19 signature genes involved in epigenetic regulation and metabolism were identified, of which DRAM1 was demonstrated to promote autophagy and glycolysis in response to E. coli infection. DRAM1 upregulation was confirmed in an independent sepsis cohort. Further, we showed that DRAM1 could maintain survival of a pro-inflammatory monocyte subset, C10_ULK1, which induces systemic inflammation by interacting with other cell subsets via resistin and integrin signaling pathways in blood and kidney tissue, respectively. Finally, retapamulin was identified and optimized as a potential drug for treatment of E. coli sepsis targeting the signature gene, DRAM1, and inhibiting E. coli protein synthesis. Several other targeted drugs were also identified in other types of sepsis, including nystatin targeting C1QA in Neisseria sepsis and dalfopristin targeting CTSD in Streptococcus viridans sepsis. CONCLUSION Our study provides a comprehensive overview of the cellular heterogeneity and underlying mechanisms in septic patients with various bacterial infections, providing insights to inform development of stratified targeted therapies for sepsis.
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Affiliation(s)
- Ping Sun
- Translational Medical Center for Stem Cell Therapy, Institute for Regenerative Medicine, School of Life Sciences and Technology, Shanghai East Hospital, Tongji University, Shanghai, 200127, China
- Department of Emergency, Affiliated Hospital of Yangzhou University, Yangzhou, 225000, China
| | - Mintian Cui
- Translational Medical Center for Stem Cell Therapy, Institute for Regenerative Medicine, School of Life Sciences and Technology, Shanghai East Hospital, Tongji University, Shanghai, 200127, China
| | - Jiongjie Jing
- Translational Medical Center for Stem Cell Therapy, Institute for Regenerative Medicine, School of Life Sciences and Technology, Shanghai East Hospital, Tongji University, Shanghai, 200127, China
| | - Fanyu Kong
- Department of Internal Emergency Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Shixi Wang
- Translational Medical Center for Stem Cell Therapy, Institute for Regenerative Medicine, School of Life Sciences and Technology, Shanghai East Hospital, Tongji University, Shanghai, 200127, China
| | - Lunxian Tang
- Department of Internal Emergency Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Junling Leng
- Department of Emergency, Affiliated Hospital of Yangzhou University, Yangzhou, 225000, China
| | - Kun Chen
- Translational Medical Center for Stem Cell Therapy, Institute for Regenerative Medicine, School of Life Sciences and Technology, Shanghai East Hospital, Tongji University, Shanghai, 200127, China.
- Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China.
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Zeng X, Zhao F, Jia J, Ma X, Jiang Q, Zhang R, Li C, Wang T, Liu W, Hao Y, Tao K, Lou Z, Zhang P. Targeting BCL6 in Gastrointestinal Stromal Tumor Promotes p53-Mediated Apoptosis to Enhance the Antitumor Activity of Imatinib. Cancer Res 2023; 83:3624-3635. [PMID: 37556508 DOI: 10.1158/0008-5472.can-23-0082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/21/2023] [Accepted: 08/04/2023] [Indexed: 08/11/2023]
Abstract
Imatinib mesylate (IM) has revolutionized the treatment of gastrointestinal stromal tumor (GIST). However, most patients inevitably acquire IM resistance. Second- and third-line treatments exhibit modest clinical benefits with a median time to disease progression of 4 to 6 months, highlighting the urgency for novel therapeutic approaches. Here, we report that the expression of BCL6, a known oncogenic driver and transcriptional repressor, was significantly induced in GIST cells following IM treatment. Elevated BCL6 levels suppressed apoptosis and contributed to IM resistance. Mechanistically, BCL6 recruited SIRT1 to the TP53 promoter to modulate histone acetylation and transcriptionally repress TP53 expression. The reduction in p53 subsequently attenuated cell apoptosis and promoted tolerance of GIST cells to IM. Concordantly, treatment of GIST cells showing high BCL6 expression with a BCL6 inhibitor, BI-3802, conferred IM sensitivity. Furthermore, BI-3802 showed striking synergy with IM in IM-responsive and IM-resistant GIST cells in vitro and in vivo. Thus, these findings reveal a role for BCL6 in IM resistance and suggest that a combination of BCL6 inhibitors and IM could be a potentially effective treatment for GIST. SIGNIFICANCE BCL6 drives resistance to imatinib by inhibiting p53-mediated apoptosis and can be targeted in combination with imatinib to synergistically suppress tumor growth, providing a therapeutic strategy for treating gastrointestinal stromal tumor.
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Affiliation(s)
- Xiangyu Zeng
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fei Zhao
- College of Biology, Hunan University, Changsha, China
| | - Jie Jia
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xianxiong Ma
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Jiang
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ruizhi Zhang
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chengguo Li
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tao Wang
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Weizhen Liu
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yalan Hao
- Analytical Instrumentation Center, Hunan University, Changsha, China
| | - Kaixiong Tao
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhenkun Lou
- Department of Oncology, Mayo Clinic, Rochester, Minnesota
| | - Peng Zhang
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Pouliou M, Koutsi MA, Champezou L, Giannopoulou AI, Vatsellas G, Piperi C, Agelopoulos M. MYCN Amplifications and Metabolic Rewiring in Neuroblastoma. Cancers (Basel) 2023; 15:4803. [PMID: 37835497 PMCID: PMC10571721 DOI: 10.3390/cancers15194803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/20/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
Cancer is a disease caused by (epi)genomic and gene expression abnormalities and characterized by metabolic phenotypes that are substantially different from the normal phenotypes of the tissues of origin. Metabolic reprogramming is one of the key features of tumors, including those established in the human nervous system. In this work, we emphasize a well-known cancerous genomic alteration: the amplification of MYCN and its downstream effects in neuroblastoma phenotype evolution. Herein, we extend our previous computational biology investigations by conducting an integrative workflow applied to published genomics datasets and comprehensively assess the impact of MYCN amplification in the upregulation of metabolism-related transcription factor (TF)-encoding genes in neuroblastoma cells. The results obtained first emphasized overexpressed TFs, and subsequently those committed in metabolic cellular processes, as validated by gene ontology analyses (GOs) and literature curation. Several genes encoding for those TFs were investigated at the mechanistic and regulatory levels by conducting further omics-based computational biology assessments applied on published ChIP-seq datasets retrieved from MYCN-amplified- and MYCN-enforced-overexpression within in vivo systems of study. Hence, we approached the mechanistic interrelationship between amplified MYCN and overexpression of metabolism-related TFs in neuroblastoma and showed that many are direct targets of MYCN in an amplification-inducible fashion. These results illuminate how MYCN executes its regulatory underpinnings on metabolic processes in neuroblastoma.
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Affiliation(s)
- Marialena Pouliou
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Marianna A. Koutsi
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Lydia Champezou
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Angeliki-Ioanna Giannopoulou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75 M. Asias Street Bldg 16, 11527 Athens, Greece;
| | - Giannis Vatsellas
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
| | - Christina Piperi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75 M. Asias Street Bldg 16, 11527 Athens, Greece;
| | - Marios Agelopoulos
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou St., 11527 Athens, Greece; (M.P.); (M.A.K.); (L.C.); (G.V.)
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5
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Cao G, Lin M, Gu W, Su Z, Duan Y, Song W, Liu H, Zhang F. The rules and regulatory mechanisms of FOXO3 on inflammation, metabolism, cell death and aging in hosts. Life Sci 2023:121877. [PMID: 37352918 DOI: 10.1016/j.lfs.2023.121877] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 06/15/2023] [Accepted: 06/20/2023] [Indexed: 06/25/2023]
Abstract
The FOX family of transcription factors was originally identified in 1989, comprising the FOXA to FOXS subfamilies. FOXO3, a well-known member of the FOXO subfamily, is widely expressed in various human organs and tissues, with higher expression levels in the ovary, skeletal muscle, heart, and spleen. The biological effects of FOXO3 are mostly determined by its phosphorylation, which occurs in the nucleus or cytoplasm. Phosphorylation of FOXO3 in the nucleus can promote its translocation into the cytoplasm and inhibit its transcriptional activity. In contrast, phosphorylation of FOXO3 in the cytoplasm leads to its translocation into the nucleus and exerts regulatory effects on biological processes, such as inflammation, aerobic glycolysis, autophagy, apoptosis, oxidative stress, cell cycle arrest and DNA damage repair. Additionally, FOXO3 isoform 2 acts as an important suppressor of osteoclast differentiation. FOXO3 can also interfere with the development of various diseases, including inhibiting the proliferation and invasion of tumor cells, blocking the production of inflammatory factors in autoimmune diseases, and inhibiting β-amyloid deposition in Alzheimer's disease. Furthermore, FOXO3 slows down the aging process and exerts anti-aging effects by delaying telomere attrition, promoting cell self-renewal, and maintaining genomic stability. This review suggests that changes in the levels and post-translational modifications of FOXO3 protein can maintain organismal homeostasis and improve age-related diseases, thus counteracting aging. Moreover, this may indicate that alterations in FOXO3 protein levels are also crucial for longevity, offering new perspectives for therapeutic strategies targeting FOXO3.
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Affiliation(s)
- Guoding Cao
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China
| | - Monan Lin
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China
| | - Wei Gu
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China
| | - Zaiyu Su
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China
| | - Yagan Duan
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China
| | - Wuqi Song
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China
| | - Hailiang Liu
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China.
| | - Fengmin Zhang
- Wu Lien-Teh Institute, Department of Microbiology, Harbin Medical University, Heilongjiang Key Laboratory of Immunity and Infection, Harbin 150081, China.
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Conserva MR, Redavid I, Anelli L, Zagaria A, Tarantini F, Cumbo C, Tota G, Parciante E, Coccaro N, Minervini CF, Minervini A, Specchia G, Musto P, Albano F. IKAROS in Acute Leukemia: A Positive Influencer or a Mean Hater? Int J Mol Sci 2023; 24:ijms24043282. [PMID: 36834692 PMCID: PMC9961161 DOI: 10.3390/ijms24043282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/31/2023] [Accepted: 02/04/2023] [Indexed: 02/11/2023] Open
Abstract
One key process that controls leukemogenesis is the regulation of oncogenic gene expression by transcription factors acting as tumor suppressors. Understanding this intricate mechanism is crucial to elucidating leukemia pathophysiology and discovering new targeted treatments. In this review, we make a brief overview of the physiological role of IKAROS and the molecular pathway that contributes to acute leukemia pathogenesis through IKZF1 gene lesions. IKAROS is a zinc finger transcription factor of the Krüppel family that acts as the main character during hematopoiesis and leukemogenesis. It can activate or repress tumor suppressors or oncogenes, regulating the survival and proliferation of leukemic cells. More than 70% of Ph+ and Ph-like cases of acute lymphoblastic leukemia exhibit IKZF1 gene variants, which are linked to worse treatment outcomes in both childhood and adult B-cell precursor acute lymphoblastic leukemia. In the last few years, much evidence supporting IKAROS involvement in myeloid differentiation has been reported, suggesting that loss of IKZF1 might also be a determinant of oncogenesis in acute myeloid leukemia. Considering the complicated "social" network that IKAROS manages in hematopoietic cells, we aim to focus on its involvement and the numerous alterations of molecular pathways it can support in acute leukemias.
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Affiliation(s)
- Maria Rosa Conserva
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Immacolata Redavid
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Luisa Anelli
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Antonella Zagaria
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Francesco Tarantini
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Cosimo Cumbo
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Giuseppina Tota
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Elisa Parciante
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Nicoletta Coccaro
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Crescenzio Francesco Minervini
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Angela Minervini
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Giorgina Specchia
- School of Medicine, University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Pellegrino Musto
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
| | - Francesco Albano
- Hematology Section, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, 70124 Bari, Italy
- Correspondence:
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Gu H, He J, Li Y, Mi D, Guan T, Guo W, Liu B, Chen Y. B-cell Lymphoma 6 Inhibitors: Current Advances and Prospects of Drug Development for Diffuse Large B-cell Lymphomas. J Med Chem 2022; 65:15559-15583. [PMID: 36441945 DOI: 10.1021/acs.jmedchem.2c01433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
B-cell lymphoma 6 (BCL6) is a transcriptional repressor that regulates the differentiation of B lymphocytes and mediates the formation of germinal centers (GCs) by recruiting corepressors through the BTB domain of BCL6. Physiological processes regulated by BCL6 involve cell activation, differentiation, DNA damage, and apoptosis. BCL6 is highly expressed when the gene is mutated, leading to the malignant proliferation of cells and drives tumorigenesis. BCL6 overexpression is closely correlated with tumorigenesis in diffuse large B-cell lymphoma (DLBCL) and other lymphomas, and BCL6 inhibitors can effectively inhibit some lymphomas and overcome resistance. Therefore, targeting BCL6 might be a promising therapeutic strategy for treating lymphomas. Herein, we comprehensively review the latest development of BCL6 inhibitors in diffuse large B-cell lymphoma and discuss the overview of the pharmacophores of BCL6 inhibitors and their efficacies in vitro and in vivo. Additionally, the current advances in BCL6 degraders are provided.
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Affiliation(s)
- Haijun Gu
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Jia He
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Yuzhan Li
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Dazhao Mi
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Tian Guan
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Weikai Guo
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Bo Liu
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, China
| | - Yihua Chen
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
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Louwen F, Kreis NN, Ritter A, Friemel A, Solbach C, Yuan J. BCL6, a key oncogene, in the placenta, pre-eclampsia and endometriosis. Hum Reprod Update 2022; 28:890-909. [PMID: 35640966 PMCID: PMC9629482 DOI: 10.1093/humupd/dmac027] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 05/02/2022] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The key oncogene B-cell lymphoma 6 (BCL6) drives malignant progression by promoting proliferation, overriding DNA damage checkpoints and blocking cell terminal differentiation. However, its functions in the placenta and the endometrium remain to be defined. OBJECTIVE AND RATIONALE Recent studies provide evidence that BCL6 may play various roles in the human placenta and the endometrium. Deregulated BCL6 might be related to the pathogenesis of pre-eclampsia (PE) as well as endometriosis. In this narrative review, we aimed to summarize the current knowledge regarding the pathophysiological role of BCL6 in these two reproductive organs, discuss related molecular mechanisms, and underline associated research perspectives. SEARCH METHODS We conducted a comprehensive literature search using PubMed for human, animal and cellular studies published until October 2021 in the following areas: BCL6 in the placenta, in PE and in endometriosis, in combination with its functions in proliferation, fusion, migration, invasion, differentiation, stem/progenitor cell maintenance and lineage commitment. OUTCOMES The data demonstrate that BCL6 is important in cell proliferation, survival, differentiation, migration and invasion of trophoblastic cells. BCL6 may have critical roles in stem/progenitor cell survival and differentiation in the placenta and the endometrium. BCL6 is aberrantly upregulated in pre-eclamptic placentas and endometriotic lesions through various mechanisms, including changes in gene transcription and mRNA translation as well as post-transcriptional/translational modifications. Importantly, increased endometrial BCL6 is considered to be a non-invasive diagnostic marker for endometriosis and a predictor for poor outcomes of IVF. These data highlight that BCL6 is crucial for placental development and endometrium homeostasis, and its upregulation is associated with the pathogenesis of PE, endometriosis and infertility. WIDER IMPLICATIONS The lesson learned from studies of the key oncogene BCL6 reinforces the notion that numerous signaling pathways and regulators are shared by tumors and reproductive organs. Their alteration may promote the progression of malignancies as well as the development of gestational and reproductive disorders.
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Affiliation(s)
- Frank Louwen
- Division of Obstetrics and Prenatal Medicine, Department of Gynecology and Obstetrics, University Hospital Frankfurt, J. W. Goethe-University, Frankfurt, Germany
| | - Nina-Naomi Kreis
- Division of Obstetrics and Prenatal Medicine, Department of Gynecology and Obstetrics, University Hospital Frankfurt, J. W. Goethe-University, Frankfurt, Germany
| | - Andreas Ritter
- Division of Obstetrics and Prenatal Medicine, Department of Gynecology and Obstetrics, University Hospital Frankfurt, J. W. Goethe-University, Frankfurt, Germany
| | - Alexandra Friemel
- Division of Obstetrics and Prenatal Medicine, Department of Gynecology and Obstetrics, University Hospital Frankfurt, J. W. Goethe-University, Frankfurt, Germany
| | - Christine Solbach
- Division of Obstetrics and Prenatal Medicine, Department of Gynecology and Obstetrics, University Hospital Frankfurt, J. W. Goethe-University, Frankfurt, Germany
| | - Juping Yuan
- Division of Obstetrics and Prenatal Medicine, Department of Gynecology and Obstetrics, University Hospital Frankfurt, J. W. Goethe-University, Frankfurt, Germany
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Influence of a Polyherbal Choline Source in Dogs: Body Weight Changes, Blood Metabolites, and Gene Expression. Animals (Basel) 2022; 12:ani12101313. [PMID: 35625159 PMCID: PMC9137459 DOI: 10.3390/ani12101313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/03/2022] [Accepted: 05/14/2022] [Indexed: 11/16/2022] Open
Abstract
Choline chloride is used to provide choline in dog foods; however, in other domestic species, it has been replaced with a polyherbal containing phosphatidylcholine. A polyherbal containing Achyrantes aspera, Trachyspermum ammi, Citrullus colocynthis, Andrographis paniculata, and Azadirachta indica was evaluated in adult dogs through body weight changes, subcutaneous fat thickness, blood metabolites, and gene expression. Forty dogs (4.6 ± 1.6 years old) who were individually housed in concrete kennels were randomly assigned to the following treatments: unsupplemented diet (377 mg choline/kg), choline chloride (3850 mg/kg equivalent to 2000 mg choline/kg diet), and polyherbal (200, 400, and 800 mg/kg) for 60 days. Blood samples were collected on day 59 for biochemistry, biometry, and gene expression analysis through microarray assays. Intake, final body weight, and weight changes were similar for the two choline sources. Feed intake variation among dogs (p = 0.01) and dorsal fat (p = 0.03) showed a quadratic response to herbal choline. Dogs that received the polyherbal diet had reduced blood cholesterol levels (Quadratic, p = 0.02). The gene ontology analysis indicated that 15 biological processes were modified (p ≤ 0.05) with implications for preventing cardiovascular and metabolic diseases, cancer prevention, inflammatory and immune response, and behavior and cognitive process. According to these results that were observed in a 60 day trial, the polyherbal form could replace choline chloride in dog diets at a concentration of 400 mg/kg.
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De Santis F, Romero-Cordoba SL, Castagnoli L, Volpari T, Faraci S, Fucà G, Tagliabue E, De Braud F, Pupa SM, Di Nicola M. BCL6 and the Notch pathway: a signaling axis leading to a novel druggable biotarget in triple negative breast cancer. Cell Oncol (Dordr) 2022; 45:257-274. [PMID: 35357654 DOI: 10.1007/s13402-022-00663-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/05/2022] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND The transcriptional repressor B-cell lymphoma 6 (BCL6) is dysregulated in several neoplasms, but its role in triple negative breast cancer (TNBC), a highly aggressive subtype which lacks effective treatment, is unclear. The presence of intratumoral cancer stem cells (CSCs) is a main cause of tumor relapse. The Notch signaling pathway is crucial for regulating CSC self-renewal and promoting breast cancer (BC) development and resistance to anticancer therapies. Here, we investigated signaling cascades of BCL6 in the CSC compartment of TNBCs, and the mechanisms that govern its activity, mainly through Notch signaling. METHODS Gene expression, somatic copy number alterations and clinical data from the Cancer Genome Atlas and METABRIC were accessed through the Xena and cbioportal browsers. Public transcriptome profiles from TNBC datasets were retrieved from the Gene Expression Omnibus. Mammosphere formation efficiency was calculated after BCL6 knockdown via transient siRNA transfection, stable silencing or pharmacological inhibition. The effects exhibited via BCL6 inhibition in putative TNBC stem-like cells were evaluated by immunofluorescence and qRT-PCR analyses. Chromatin immunoprecipitation experiments were performed to validate a putative BCL6 responsive element located in the first intron of the Numb gene and to define the circuit of corepressors engaged by BCL6 following its inhibition. Immunoprecipitation assays were carried out to investigate a novel interaction at the basis of BCL6 control of CSC activity in TNBC. RESULTS In silico analyses of benchmarked public datasets revealed a significant enrichment of BCL6 in cancer stemness related pathways, particularly of Notch signaling in TNBC. In vitro stable inhibition of BCL6 significantly reduced tumor cell growth and, accordingly, we found that the mammosphere formation efficiency of BCL6 silenced cells was significantly impaired by pharmacological inhibition of Notch signaling. BCL6 was found to be expressed at significantly higher levels in TNBC mammospheres than in their adherent counterparts, and loss of BCL6 function significantly decreased mammosphere formation with preferential targeting of CD44-positive versus ALDH-positive stem-like cells. Functional interplay between BCL6 and the chromatin remodeling factor EZH2 triggered the BCL6/Notch stemness signaling axis via inhibition of Numb transcription. CONCLUSIONS Our results may be instrumental for the prospective design of combination treatment strategies that selectively target novel TNBC-associated biomarker(s) whose activity is implicated in the regulation of cancer stemness (such as BCL6) and molecules in developmentally conserved signaling pathways (such as Notch) to achieve long-lasting tumor control and improve patient outcomes.
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Affiliation(s)
- Francesca De Santis
- Unit of Immunotherapy and Anticancer Innovative Therapeutics, Department of Medical Oncology and Hematology Fondazione, IRCCS Istituto Nazionale Dei Tumori, Milan, Italy
| | - Sandra L Romero-Cordoba
- Department of Genomic Medicine and Toxicology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Biochemistry Department, Instituto Nacional de Ciencias Médicas Y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - Lorenzo Castagnoli
- Molecular Targeting Unit, Department of Research, Fondazione IRCCS Istituto Nazionale Dei Tumori, Milan, Italy
| | - Tatiana Volpari
- The New York Stem Cell Foundation Research Institute, New York, NY, USA
| | - Simona Faraci
- Molecular Targeting Unit, Department of Research, Fondazione IRCCS Istituto Nazionale Dei Tumori, Milan, Italy
| | - Giovanni Fucà
- Unit of Immunotherapy and Anticancer Innovative Therapeutics, Department of Medical Oncology and Hematology Fondazione, IRCCS Istituto Nazionale Dei Tumori, Milan, Italy
| | - Elda Tagliabue
- Molecular Targeting Unit, Department of Research, Fondazione IRCCS Istituto Nazionale Dei Tumori, Milan, Italy
| | - Filippo De Braud
- Department of Medical Oncology and Hematology, Fondazione IRCCS Istituto Nazionale Dei Tumori, Milan, Italy.,Department of Oncology and Oncohematology, University of Milan, Milan, Italy
| | - Serenella M Pupa
- Molecular Targeting Unit, Department of Research, Fondazione IRCCS Istituto Nazionale Dei Tumori, Milan, Italy
| | - Massimo Di Nicola
- Unit of Immunotherapy and Anticancer Innovative Therapeutics, Department of Medical Oncology and Hematology Fondazione, IRCCS Istituto Nazionale Dei Tumori, Milan, Italy.
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11
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Li J, Ma Y, Paquette JK, Richards AC, Mulvey MA, Zachary JF, Teuscher C, Weis JJ. The Cdkn2a gene product p19 alternative reading frame (p19ARF) is a critical regulator of IFNβ-mediated Lyme arthritis. PLoS Pathog 2022; 18:e1010365. [PMID: 35324997 PMCID: PMC8946740 DOI: 10.1371/journal.ppat.1010365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 02/11/2022] [Indexed: 11/18/2022] Open
Abstract
Type I interferon (IFN) has been identified in patients with Lyme disease, and its abundant expression in joint tissues of C3H mice precedes development of Lyme arthritis. Forward genetics using C3H mice with severe Lyme arthritis and C57BL/6 (B6) mice with mild Lyme arthritis identified the Borrelia burgdorferi arthritis-associated locus 1 (Bbaa1) on chromosome 4 (Chr4) as a regulator of B. burgdorferi-induced IFNβ expression and Lyme arthritis severity. B6 mice introgressed with the C3H allele for Bbaa1 (B6.C3-Bbaa1 mice) displayed increased severity of arthritis, which is initiated by myeloid lineage cells in joints. Using advanced congenic lines, the physical size of the Bbaa1 interval has been reduced to 2 Mbp, allowing for identification of potential genetic regulators. Small interfering RNA (siRNA)-mediated silencing identified Cdkn2a as the gene responsible for Bbaa1 allele-regulated induction of IFNβ and IFN-stimulated genes (ISGs) in bone marrow-derived macrophages (BMDMs). The Cdkn2a-encoded p19 alternative reading frame (p19ARF) protein regulates IFNβ induction in BMDMs as shown by siRNA silencing and overexpression of ARF. In vivo studies demonstrated that p19ARF contributes to joint-specific induction of IFNβ and arthritis severity in B. burgdorferi-infected mice. p19ARF regulates B. burgdorferi-induced IFNβ in BMDMs by stabilizing the tumor suppressor p53 and sequestering the transcriptional repressor BCL6. Our findings link p19ARF regulation of p53 and BCL6 to the severity of IFNβ-induced Lyme arthritis in vivo and indicate potential novel roles for p19ARF, p53, and BCL6 in Lyme disease and other IFN hyperproduction syndromes. Lyme disease is caused by infection with the tick-transmitted bacterium Borrelia burgdorferi. Although different isolates of B. burgdorferi have distinct potential for dissemination and tissue invasion, factors intrinsic to the infected host also play an important role in directing the severity of Lyme disease. In the animal model, infected C3H mice develop severe Lyme arthritis following elevation of type I IFN in joint tissue, while in C57BL/6 (B6) mice arthritis is mild and not associated with type I IFN. We demonstrated that the Borrelia burgdorferi arthritis-associated locus 1 (Bbaa1) on chromosome 4 (Chr4) intrinsically controls the magnitude of IFNβ production and the severity of Lyme arthritis in C3H vs B6 mice. The Cdkn2a gene was positionally identified as the regulator of IFNβ within Bbaa1, and determined to function through its protein product p19 alternative reading frame (p19ARF). ARF regulates IFNβ expression and Lyme arthritis severity by modulating the activities of the tumor suppressor p53 and transcriptional repressor BCL6. Our study provides new insight and potential therapeutic targets for the investigation of type I IFN-dependent Lyme arthritis and other IFN-driven diseases.
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Affiliation(s)
- Jinze Li
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
| | - Ying Ma
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
| | - Jackie K. Paquette
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
| | - Amanda C. Richards
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
| | - Matthew A. Mulvey
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
| | - James F. Zachary
- Department of Veterinary Pathobiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Cory Teuscher
- Department of Medicine, Vermont Center for Immunology and Infectious Diseases, Larner College of Medicine, The University of Vermont, Burlington, Vermont, United States of America
| | - Janis J. Weis
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
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12
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Schaefer EJ, Wang HC, Karp HQ, Meyer CA, Cejas P, Gearhart MD, Adelman ER, Fares I, Apffel A, Lim K, Xie Y, Gibson CJ, Schenone M, Murdock HM, Wang ES, Gondek LP, Carroll MP, Vedula RS, Winer ES, Garcia JS, Stone RM, Luskin MR, Carr SA, Long HW, Bardwell VJ, Figueroa ME, Lindsley RC. BCOR and BCORL1 Mutations Drive Epigenetic Reprogramming and Oncogenic Signaling by Unlinking PRC1.1 from Target Genes. Blood Cancer Discov 2022; 3:116-135. [PMID: 35015684 PMCID: PMC9414116 DOI: 10.1158/2643-3230.bcd-21-0115] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 11/06/2021] [Accepted: 12/10/2021] [Indexed: 02/02/2023] Open
Abstract
Polycomb repressive epigenetic complexes are recurrently dysregulated in cancer. Unlike polycomb repressive complex 2 (PRC2), the role of PRC1 in oncogenesis and therapy resistance is not well-defined. Here, we demonstrate that highly recurrent mutations of the PRC1 subunits BCOR and BCORL1 in leukemia disrupt assembly of a noncanonical PRC1.1 complex, thereby selectively unlinking the RING-PCGF enzymatic core from the chromatin-targeting auxiliary subcomplex. As a result, BCOR-mutated PRC1.1 is localized to chromatin but lacks repressive activity, leading to epigenetic reprogramming and transcriptional activation at target loci. We define a set of functional targets that drive aberrant oncogenic signaling programs in PRC1.1-mutated cells and primary patient samples. Activation of these PRC1.1 targets in BCOR-mutated cells confers acquired resistance to treatment while sensitizing to targeted kinase inhibition. Our study thus reveals a novel epigenetic mechanism that explains PRC1.1 tumor-suppressive activity and identifies a therapeutic strategy in PRC1.1-mutated cancer. SIGNIFICANCE We demonstrate that BCOR and BCORL1 mutations in leukemia unlink PRC1.1 repressive function from target genes, resulting in epigenetic reprogramming and activation of aberrant cell signaling programs that mediate treatment resistance. Our study provides mechanistic insights into the pathogenesis of PRC1.1-mutated leukemia that inform novel therapeutic approaches. This article is highlighted in the In This Issue feature, p. 85.
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Affiliation(s)
- Eva J. Schaefer
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Helen C. Wang
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Hannah Q. Karp
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Clifford A. Meyer
- Department of Data Science, Dana-Farber Cancer Institute, and Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Paloma Cejas
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Micah D. Gearhart
- Developmental Biology Center, Masonic Cancer Center, and Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota
| | - Emmalee R. Adelman
- Sylvester Comprehensive Cancer Center, Department of Human Genetics, University of Miami, Miller School of Medicine, Miami, Florida.,Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, Florida
| | - Iman Fares
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Annie Apffel
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts
| | - Klothilda Lim
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Yingtian Xie
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Christopher J. Gibson
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Monica Schenone
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts
| | - H. Moses Murdock
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Eunice S. Wang
- Department of Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Lukasz P. Gondek
- Division of Molecular Pathology, Department of Pathology, Johns Hopkins University, Baltimore, Maryland
| | - Martin P. Carroll
- Department of Medicine, Perelman Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rahul S. Vedula
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Eric S. Winer
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Jacqueline S. Garcia
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Richard M. Stone
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Marlise R. Luskin
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Steven A. Carr
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts
| | - Henry W. Long
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Vivian J. Bardwell
- Developmental Biology Center, Masonic Cancer Center, and Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota
| | - Maria E. Figueroa
- Sylvester Comprehensive Cancer Center, Department of Human Genetics, University of Miami, Miller School of Medicine, Miami, Florida
| | - R. Coleman Lindsley
- Department of Medical Oncology, Division of Hematologic Neoplasia, Dana-Farber Cancer Institute, Boston, Massachusetts.,Corresponding Author: R. Coleman Lindsley, Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215. Phone: 617-632-6649; E-mail:
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13
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Fang SG, Xia TL, Fu JC, Li T, Zhong Q, Han F. BCL6-SPECC1L: A Novel Fusion Gene in Nasopharyngeal Carcinoma. Technol Cancer Res Treat 2022; 21:15330338221139981. [PMID: 36412101 PMCID: PMC9706053 DOI: 10.1177/15330338221139981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 10/28/2022] [Accepted: 11/02/2022] [Indexed: 07/30/2023] Open
Abstract
Background: Nasopharyngeal carcinomas (NPCs) are malignant tumors originating from the lining epithelium of the nasopharynx. Fusion genes have been confirmed to play important roles in the occurrence and development of various malignant tumors, but the role of fusion genes in NPC is poorly understood. We aimed to explore new fusion genes that promote the occurrence and development of NPC. Methods: RNA-seq was used to search for interchromosomal translocations in 18 NPC tissues. Polymerase chain reaction (PCR) and Sanger sequencing were applied to verify the presence of BCL6-SPECC1L (BS); quantitative PCR (qPCR) and Western blotting were used to measure the expression level of BCL-6 in NPC cells; MTT and in vivo tumorigenesis assays were applied to evaluate the cell proliferation ability; immunofluorescence assays were used to determine the cellular localization of BCL6 and BS; and a luciferase reporter assay was performed to evaluate the ability of BCL6 and BS to inhibit transcription. Results: BS was present in 5.34% (11/206) of primary NPC biopsies and 2.13% (1/47) of head and neck cancer biopsies. The expression of BCL6 was downregulated in NPC, and silencing of endogenous BCL6 promoted NPC cell proliferation in vitro. Overexpression of BCL6 but not BS inhibited the growth of NPC cells in vivo and in vitro. Mechanistically, BCL6 localized in the nucleus can inhibit the G1/S transition to suppress the growth of NPC cells. However, after the fusion of BCL6 and SPECC1L, the product cannot localize to the nucleus, and the transcriptional inhibitory function of BCL6 is abolished, eventually abolishing its tumor suppressor effect and leading to the development of NPC. Conclusion: BS is a novel fusion gene in NPC that may play an important role in the occurrence and development of this cancer. The clinical significance of the BS fusion gene needs further elucidation.
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Affiliation(s)
- Shuo-Gui Fang
- Department of Radiation Oncology, Sun Yat-sen University Cancer
Center, Guangzhou, Guangdong, China
- Department of Thoracic Surgery, Sun Yat-sen University Cancer
Center, Guangzhou, Guangdong, China
- State Key Laboratory of Oncology in South China, Guangzhou,
China
- Collaborative Innovation Center for Cancer Medicine, Guangzhou,
China
| | - Tian-Liang Xia
- State Key Laboratory of Oncology in South China, Guangzhou,
China
- Collaborative Innovation Center for Cancer Medicine, Guangzhou,
China
| | - Jian-Chang Fu
- Collaborative Innovation Center for Cancer Medicine, Guangzhou,
China
- Department of Pathology, Sun Yat-Sen University Cancer
Center, Guangzhou, China
| | - Tong Li
- Department of Cancer Prevention, Sun Yat-sen University Cancer
Center, Guangzhou, China
| | - Qian Zhong
- State Key Laboratory of Oncology in South China, Guangzhou,
China
| | - Fei Han
- Department of Radiation Oncology, Sun Yat-sen University Cancer
Center, Guangzhou, Guangdong, China
- State Key Laboratory of Oncology in South China, Guangzhou,
China
- Collaborative Innovation Center for Cancer Medicine, Guangzhou,
China
- Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and
Therapy, Guangzhou, China
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14
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Epstein Barr virus-positive B-cell lymphoma is highly vulnerable to MDM2 inhibitors in vivo. Blood Adv 2021; 6:891-901. [PMID: 34861697 PMCID: PMC8945299 DOI: 10.1182/bloodadvances.2021006156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/25/2021] [Indexed: 11/20/2022] Open
Abstract
MDM2 inhibitors have potent in vivo activity against and could be a novel therapy for EBV-positive B-cell lymphoma. EBV positivity or loss of BCL6 expression can be a potential predictive biomarker for response to MDM2 inhibitors in patients with lymphoma
Epstein-Barr virus–positive (EBV-positive) B-cell lymphomas are common in immunocompromised patients and remain an unmet medical need. Here we report that MDM2 inhibitors (MDM2is) navtemadlin and idasanutlin have potent in vivo activity in EBV-positive B-cell lymphoma established in immunocompromised mice. Tumor regression was observed in all 5 EBV-positive xenograft–associated B-cell lymphomas treated with navtemadlin or idasanutlin. Molecular characterization showed that treatment with MDM2is resulted in activation of p53 pathways and downregulation of cell cycle effectors in human lymphoma cell lines that were either EBV-positive or had undetectable expression of BCL6, a transcriptional inhibitor of the TP53 gene. Moreover, treatment with navtemadlin resulted in tumor regression and prevented systemic dissemination of EBV-positive lymphoma derived from 2 juvenile patients with posttransplant lymphoproliferative diseases, including 1 whose tumor was resistant to virus-specific T-cell therapy. These results provide proof-of-concept for targeted therapy of EBV-positive lymphoma with MDM2is and the feasibility of using EBV infection or loss of BCL6 expression to identify responders to MDM2is.
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15
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Leukemia Stem Cells as a Potential Target to Achieve Therapy-Free Remission in Chronic Myeloid Leukemia. Cancers (Basel) 2021; 13:cancers13225822. [PMID: 34830976 PMCID: PMC8616035 DOI: 10.3390/cancers13225822] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 12/26/2022] Open
Abstract
Leukemia stem cells (LSCs, also known as leukemia-initiating cells) not only drive leukemia initiation and progression, but also contribute to drug resistance and/or disease relapse. Therefore, eradication of every last LSC is critical for a patient's long-term cure. Chronic myeloid leukemia (CML) is a myeloproliferative disorder that arises from multipotent hematopoietic stem and progenitor cells. Tyrosine kinase inhibitors (TKIs) have dramatically improved long-term outcomes and quality of life for patients with CML in the chronic phase. Point mutations of the kinase domain of BCR-ABL1 lead to TKI resistance through a reduction in drug binding, and as a result, several new generations of TKIs have been introduced to the clinic. Some patients develop TKI resistance without known mutations, however, and the presence of LSCs is believed to be at least partially associated with resistance development and CML relapse. We previously proposed targeting quiescent LSCs as a therapeutic approach to CML, and a number of potential strategies for targeting insensitive LSCs have been presented over the last decade. The identification of specific markers distinguishing CML-LSCs from healthy HSCs, and the potential contributions of the bone marrow microenvironment to CML pathogenesis, have also been explored. Nonetheless, 25% of CML patients are still expected to switch TKIs at least once, and various TKI discontinuation studies have shown a wide range in the incidence of molecular relapse (from 30% to 60%). In this review, we revisit the current knowledge regarding the role(s) of LSCs in CML leukemogenesis and response to pharmacological treatment and explore how durable treatment-free remission may be achieved and maintained after discontinuing TKI treatment.
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16
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Amir M, Javed S. A Review on the Therapeutic Role of TKIs in Case of CML in Combination With Epigenetic Drugs. Front Genet 2021; 12:742802. [PMID: 34745216 PMCID: PMC8569791 DOI: 10.3389/fgene.2021.742802] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/30/2021] [Indexed: 01/09/2023] Open
Abstract
Chronic myeloid leukemia is a malignancy of bone marrow that affects white blood cells. There is strong evidence that disease progression, treatment responses, and overall clinical outcomes of CML patients are influenced by the accumulation of other genetic and epigenetic abnormalities, rather than only the BCR/ABL1 oncoprotein. Both genetic and epigenetic factors influence the efficacy of CML treatment strategies. Targeted medicines known as tyrosine-kinase inhibitors have dramatically improved long-term survival rates in CML patients during the previous 2 decades. When compared to earlier chemotherapy treatments, these drugs have revolutionized CML treatment and allowed most people to live longer lives. Although epigenetic inhibitors' activity is disrupted in many cancers, including CML, but when combined with TKI, they may offer potential therapeutic strategies for the treatment of CML cells. The epigenetics of tyrosine kinase inhibitors and resistance to them is being studied, with a particular focus on imatinib, which is used to treat CML. In addition, the use of epigenetic drugs in conjunction with TKIs has been discussed. Resistance to TKIs is still a problem in curing the disease, necessitating the development of new therapies. This study focused on epigenetic pathways involved in CML pathogenesis and tumor cell resistance to TKIs, both of which contribute to leukemic clone breakout and proliferation.
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Affiliation(s)
| | - Saleem Javed
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
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17
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ANP32B-mediated repression of p53 contributes to maintenance of normal and CML stem cells. Blood 2021; 138:2485-2498. [PMID: 34359074 DOI: 10.1182/blood.2020010400] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 08/03/2021] [Indexed: 11/20/2022] Open
Abstract
Proper regulation of p53 signaling is critical for the maintenance of hematopoietic stem cells (HSCs) and leukemic stem cells (LSCs). The hematopoietic cell-specific mechanisms regulating p53 activity remain largely unknown. Here, we demonstrate that conditional deletion of acidic leucine-rich nuclear phosphoprotein 32B (ANP32B) in hematopoietic cells impairs repopulation capacity and post-injury regeneration of HSCs. Mechanistically, ANP32B forms a repressive complex with and thus inhibits the transcriptional activity of p53 in hematopoietic cells, and p53 deletion rescues the functional defect in Anp32b-deficient HSCs. Of great interest, ANP32B is highly expressed in leukemic cells from chronic myelogenous leukemia (CML) patients. Anp32b deletion enhances p53 transcriptional activity to impair LSCs function in a murine CML model, and exhibits synergistic therapeutic effects with tyrosine kinase inhibitors in inhibiting CML propagation. In summary, our findings provide a novel strategy to enhance p53 activity in LSCs by inhibiting ANP32B, and identify ANP32B as a potential therapeutic target in treating CML.
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18
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BCL6 maintains survival and self-renewal of primary human acute myeloid leukemia cells. Blood 2021; 137:812-825. [PMID: 32911532 DOI: 10.1182/blood.2019001745] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 08/25/2020] [Indexed: 12/28/2022] Open
Abstract
B-cell lymphoma 6 (BCL6) is a transcription repressor and proto-oncogene that plays a crucial role in the innate and adaptive immune system and lymphoid neoplasms. However, its role in myeloid malignancies remains unclear. Here, we explored the role of BCL6 in acute myeloid leukemia (AML). BCL6 was expressed at variable and often high levels in AML cell lines and primary AML samples. AMLs with higher levels of BCL6 were generally sensitive to treatment with BCL6 inhibitors, with the exception of those with monocytic differentiation. Gene expression profiling of AML cells treated with a BCL6 inhibitor revealed induction of BCL6-repressed target genes and transcriptional programs linked to DNA damage checkpoints and downregulation of stem cell genes. Ex vivo treatment of primary AML cells with BCL6 inhibitors induced apoptosis and decreased colony-forming capacity, which correlated with the levels of BCL6 expression. Importantly, inhibition or knockdown of BCL6 in primary AML cells resulted in a significant reduction of leukemia-initiating capacity in mice, suggesting ablation of leukemia repopulating cell functionality. In contrast, BCL6 knockout or inhibition did not suppress the function of normal hematopoietic stem cells. Treatment with cytarabine further induced BCL6 expression, and the levels of BCL6 induction were correlated with resistance to cytarabine. Treatment of AML patient-derived xenografts with BCL6 inhibitor plus cytarabine suggested enhanced antileukemia activity with this combination. Hence, pharmacologic inhibition of BCL6 might provide a novel therapeutic strategy for ablation of leukemia-repopulating cells and increased responsiveness to chemotherapy.
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19
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BCOR gene alterations in hematological diseases. Blood 2021; 138:2455-2468. [PMID: 33945606 DOI: 10.1182/blood.2021010958] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/14/2021] [Indexed: 11/20/2022] Open
Abstract
The BCL6 co-repressor (BCOR) is a transcription factor involved in the control of embryogenesis, mesenchymal stem cells function, hematopoiesis and lymphoid development. Recurrent somatic clonal mutations of the BCOR gene and its homologue BCORL1 have been detected in several hematological malignancies and aplastic anemia. They are scattered across the whole gene length and mostly represent frameshifts (deletions, insertions), nonsense and missence mutations. These disruptive events lead to the loss of full-length BCOR protein and to the lack or low expression of a truncated form of the protein, both consistent with the tumor suppressor role of BCOR. BCOR and BCORL1 mutations are similar to those causing two rare X-linked diseases: the oculo-facio-cardio-dental (OFCD) and the Shukla-Vernon syndromes, respectively. Here, we focus on the structure and function of normal BCOR and BCORL1 in normal hematopoietic and lymphoid tissues and review the frequency and clinical significance of the mutations of these genes in malignant and non-malignant hematological diseases. Moreover, we discuss the importance of mouse models to better understand the role of Bcor loss, alone and combined with alterations of other genes (e.g. Dnmt3a and Tet2), in promoting hematological malignancies and in providing a useful platform for the development of new targeted therapies.
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20
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Ai Y, Hwang L, MacKerell AD, Melnick A, Xue F. Progress toward B-Cell Lymphoma 6 BTB Domain Inhibitors for the Treatment of Diffuse Large B-Cell Lymphoma and Beyond. J Med Chem 2021; 64:4333-4358. [PMID: 33844535 DOI: 10.1021/acs.jmedchem.0c01686] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
B-cell lymphoma 6 (BCL6) is a master regulator of germinal center formation that produce antibody-secreting plasma cells and memory B-cells for sustained immune responses. The BTB domain of BCL6 (BCL6BTB) forms a homodimer that mediates transcriptional repression by recruiting its corepressor proteins to form a biologically functional transcriptional complex. The protein-protein interaction (PPI) between the BCL6BTB and its corepressors has emerged as a therapeutic target for the treatment of DLBCL and a number of other human cancers. This Perspective provides an overview of recent advances in the development of BCL6BTB inhibitors from reversible inhibitors, irreversible inhibitors, to BCL6 degraders. Inhibitor design and medicinal chemistry strategies for the development of novel compounds will be provided. The binding mode of new inhibitors to BCL6BTB are highlighted. Also, the in vitro and in vivo assays used for the evaluation of new compounds will be discussed.
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Affiliation(s)
- Yong Ai
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, Maryland 21201, United States
| | - Lucia Hwang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, Maryland 21201, United States
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, Maryland 21201, United States
| | - Ari Melnick
- Department of Hematology and Oncology, Weill Cornell Medical College, New York, New York 10021, United States.,Department of Pharmacology, Weill Cornell Medical College, New York, New York 10021, United States
| | - Fengtian Xue
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, Maryland 21201, United States
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21
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The Roles of FOXO1 in Periodontal Homeostasis and Disease. J Immunol Res 2021; 2021:5557095. [PMID: 33860060 PMCID: PMC8026307 DOI: 10.1155/2021/5557095] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/07/2021] [Accepted: 03/13/2021] [Indexed: 02/05/2023] Open
Abstract
Periodontitis is an oral chronic inflammatory disease that is initiated by periodontal microbial communities and requires disruption of the homeostatic responses. The prevalence of periodontal disease increases with age; more than 70% of adults 65 years and older have periodontal disease. A pathogenic microbial community is required for initiating periodontal disease. Dysbiotic immune-inflammatory response and bone remodeling are characteristics of periodontitis. The transcription factor forkhead box protein O1 (FOXO1) is a key regulator of a number of cellular processes, including cell survival and differentiation, immune status, reactive oxygen species (ROS) scavenging, and apoptosis. Although accumulating evidence indicates that FOXO1 activity can be induced by periodontal pathogens, the roles of FOXO1 in periodontal homeostasis and disease have not been well documented. The present review summarizes how the FOXO1 signaling axis can regulate periodontal bacteria-epithelial interactions, immune-inflammatory response, bone remodeling, and wound healing.
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AML displays increased CTCF occupancy associated with aberrant gene expression and transcription factor binding. Blood 2021; 136:339-352. [PMID: 32232485 DOI: 10.1182/blood.2019002326] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 03/01/2020] [Indexed: 12/11/2022] Open
Abstract
CCTC-binding factor (CTCF) is a key regulator of gene expression through organization of the chromatin structure. Still, it is unclear how CTCF binding is perturbed in leukemia or in cancer in general. We studied CTCF binding by chromatin immunoprecipitation sequencing in cells from patients with acute myeloid leukemia (AML) and in normal bone marrow (NBM) in the context of gene expression, DNA methylation, and azacitidine exposure. CTCF binding was increased in AML compared with NBM. Aberrant CTCF binding was enriched for motifs for key myeloid transcription factors such as CEBPA, PU.1, and RUNX1. AML with TET2 mutations was characterized by a particularly strong gain of CTCF binding, highly enriched for gain in promoter regions, while AML in general was enriched for changes at enhancers. There was a strong anticorrelation between CTCF binding and DNA methylation. Gain of CTCF occupancy was associated with increased gene expression; however, the genomic location (promoter vs distal regions) and enrichment of motifs (for repressing vs activating cofactors) were decisive for the gene expression pattern. Knockdown of CTCF in K562 cells caused loss of CTCF binding and transcriptional repression of genes with changed CTCF binding in AML, as well as loss of RUNX1 binding at RUNX1/CTCF-binding sites. In addition, CTCF knockdown caused increased differentiation. Azacitidine exposure caused major changes in CTCF occupancy in AML patient cells, partly by restoring a CTCF-binding pattern similar to NBM. We conclude that AML displays an aberrant increase in CTCF occupancy that targets key genes for AML development and impacts gene expression.
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23
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Cancer Stem Cells-Key Players in Tumor Relapse. Cancers (Basel) 2021; 13:cancers13030376. [PMID: 33498502 PMCID: PMC7864187 DOI: 10.3390/cancers13030376] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/10/2021] [Accepted: 01/18/2021] [Indexed: 02/06/2023] Open
Abstract
Tumor relapse and treatment failure are unfortunately common events for cancer patients, thus often rendering cancer an uncurable disease. Cancer stem cells (CSCs) are a subset of cancer cells endowed with tumor-initiating and self-renewal capacity, as well as with high adaptive abilities. Altogether, these features contribute to CSC survival after one or multiple therapeutic approaches, thus leading to treatment failure and tumor progression/relapse. Thus, elucidating the molecular mechanisms associated with stemness-driven resistance is crucial for the development of more effective drugs and durable responses. This review will highlight the mechanisms exploited by CSCs to overcome different therapeutic strategies, from chemo- and radiotherapies to targeted therapies and immunotherapies, shedding light on their plasticity as an insidious trait responsible for their adaptation/escape. Finally, novel CSC-specific approaches will be described, providing evidence of their preclinical and clinical applications.
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25
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Chen B, Ye P, Chen Y, Liu T, Cha JH, Yan X, Yang WH. Involvement of the Estrogen and Progesterone Axis in Cancer Stemness: Elucidating Molecular Mechanisms and Clinical Significance. Front Oncol 2020; 10:1657. [PMID: 33014829 PMCID: PMC7498570 DOI: 10.3389/fonc.2020.01657] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 07/28/2020] [Indexed: 12/21/2022] Open
Abstract
Estrogen and progesterone regulate the growth and development of human tissues, including the reproductive system and breasts, through estrogen and progesterone receptors, respectively. These receptors are also important indicators for the clinical prognosis of breast cancer and various reproductive cancers. Many studies have reported that cancer stem cells (CSCs) play a key role in tumor initiation, progression, metastasis, and recurrence. Although the role of estrogen and progesterone in human organs and various cancers has been studied, the molecular mechanisms underlying the action of these hormones on CSCs remain unclear. Therefore, further elucidation of the effects of estrogen and progesterone on CSCs should provide a new direction for developing pertinent therapies. In this review, we summarize the current knowledge on the estrogen and progesterone axis involved in cancer stemness and discuss potential therapeutic strategies to inhibit CSCs by targeting relevant pathways.
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Affiliation(s)
- Bi Chen
- Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, China
| | - Peng Ye
- Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, China
| | - Yeh Chen
- Institute of New Drug Development, China Medical University, Taichung, Taiwan
| | - Tong Liu
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, China.,The Institute of Cancer Prevention and Treatment, Harbin Medical University, Harbin, China
| | - Jong-Ho Cha
- Department of Biomedical Sciences, College of Medicine, Inha University, Incheon, South Korea
| | - Xiuwen Yan
- Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, China
| | - Wen-Hao Yang
- Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, China.,Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
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26
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Yin Z, Huang G, Gu C, Liu Y, Yang J, Fei J. Discovery of Berberine that Targetedly Induces Autophagic Degradation of both BCR-ABL and BCR-ABL T315I through Recruiting LRSAM1 for Overcoming Imatinib Resistance. Clin Cancer Res 2020; 26:4040-4053. [PMID: 32098768 DOI: 10.1158/1078-0432.ccr-19-2460] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 12/03/2019] [Accepted: 02/20/2020] [Indexed: 11/16/2022]
Abstract
PURPOSE Imatinib, the breakpoint cluster region protein (BCR)/Abelson murine leukemia viral oncogene homolog (ABL) inhibitor, is widely used to treat chronic myeloid leukemia (CML). However, imatinib resistance develops in many patients. Therefore, new drugs with improved therapeutic effects are urgently needed. Berberine (BBR) is a potent BCR-ABL inhibitor for imatinib-sensitive and -resistant CML. EXPERIMENTAL DESIGN Protein structure analysis and virtual screening were used to identify BBR targets in CML. Molecular docking analysis, surface plasmon resonance imaging, nuclear magnetic resonance assays, and thermoshift assays were performed to confirm the BBR target. The change in BCR-ABL protein expression after BBR treatment was assessed by Western blotting. The effects of BBR were assessed in vitro in cell lines, in vivo in mice, and in human CML bone marrow cells as a potential strategy to overcome imatinib resistance. RESULTS We discovered that BBR bound to the protein tyrosine kinase domain of BCR-ABL. BBR inhibited the activity of BCR-ABL and BCR-ABL with the T315I mutation, and it also degraded these proteins via the autophagic lysosome pathway by recruiting E3 ubiquitin-protein ligase LRSAM1. BBR inhibited the cell viability and colony formation of CML cells and prolonged survival in CML mouse models with imatinib sensitivity and resistance. CONCLUSIONS The results show that BBR directly binds to and degrades BCR-ABL and BCR-ABL T315I via the autophagic lysosome pathway by recruiting LRSAM1. The use of BBR is a new strategy to improve the treatment of patients with CML with imatinib sensitivity or resistance.See related commentary by Elf, p. 3899.
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Affiliation(s)
- Zhao Yin
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, Guangzhou, China.,Institute of Chinese Integrative Medicine, Medical College of Jinan University, Guangzhou, China.,Engineering Technology Research Center of Drug Development for Small Nucleic Acids, Guangdong, China.,Antisense Biopharmaceutical Technology Co., Ltd., Guangzhou, China
| | - Guiping Huang
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, Guangzhou, China.,Engineering Technology Research Center of Drug Development for Small Nucleic Acids, Guangdong, China.,Antisense Biopharmaceutical Technology Co., Ltd., Guangzhou, China
| | - Chunming Gu
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, Guangzhou, China.,Institute of Chinese Integrative Medicine, Medical College of Jinan University, Guangzhou, China.,Engineering Technology Research Center of Drug Development for Small Nucleic Acids, Guangdong, China.,Antisense Biopharmaceutical Technology Co., Ltd., Guangzhou, China
| | - Yanjun Liu
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, Guangzhou, China.,Engineering Technology Research Center of Drug Development for Small Nucleic Acids, Guangdong, China.,Antisense Biopharmaceutical Technology Co., Ltd., Guangzhou, China
| | - Juhua Yang
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, Guangzhou, China.,Engineering Technology Research Center of Drug Development for Small Nucleic Acids, Guangdong, China.,Antisense Biopharmaceutical Technology Co., Ltd., Guangzhou, China
| | - Jia Fei
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, Guangzhou, China. .,Institute of Chinese Integrative Medicine, Medical College of Jinan University, Guangzhou, China.,Engineering Technology Research Center of Drug Development for Small Nucleic Acids, Guangdong, China.,Antisense Biopharmaceutical Technology Co., Ltd., Guangzhou, China
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27
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Signal-transducing adapter protein-1 is required for maintenance of leukemic stem cells in CML. Oncogene 2020; 39:5601-5615. [PMID: 32661325 PMCID: PMC7441008 DOI: 10.1038/s41388-020-01387-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 06/12/2020] [Accepted: 07/03/2020] [Indexed: 12/26/2022]
Abstract
The family of signal-transducing adapter proteins (STAPs) has been reported to be involved in a variety of intracellular signaling pathways and implicated as transcriptional factors. We previously cloned STAP-2 as a c-Fms interacting protein and explored its effects on chronic myeloid leukemia (CML) leukemogenesis. STAP-2 binds to BCR-ABL, upregulates BCR-ABL phosphorylation, and activates its downstream molecules. In this study, we evaluated the role of STAP-1, another member of the STAP family, in CML pathogenesis. We found that the expression of STAP-1 is aberrantly upregulated in CML stem cells (LSCs) in patients’ bone marrow. Using experimental model mice, deletion of STAP-1 prolonged the survival of CML mice with inducing apoptosis of LSCs. The impaired phosphorylation status of STAT5 by STAP-1 ablation leads to downregulation of antiapoptotic genes, Bcl-2 and Bcl-xL. Interestingly, transcriptome analyses indicated that STAP-1 affects several signaling pathways related to BCR-ABL, JAK2, and PPARγ. This adapter protein directly binds to not only BCR-ABL, but also STAT5 proteins, showing synergistic effects of STAP-1 inhibition and BCR-ABL or JAK2 tyrosine kinase inhibition. Our results identified STAP-1 as a regulator of CML LSCs and suggested it to be a potential therapeutic target for CML.
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28
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Transcriptional Regulation of Genes by Ikaros Tumor Suppressor in Acute Lymphoblastic Leukemia. Int J Mol Sci 2020; 21:ijms21041377. [PMID: 32085659 PMCID: PMC7073093 DOI: 10.3390/ijms21041377] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 02/13/2020] [Accepted: 02/14/2020] [Indexed: 12/27/2022] Open
Abstract
Regulation of oncogenic gene expression by transcription factors that function as tumor suppressors is one of the major mechanisms that regulate leukemogenesis. Understanding this complex process is essential for explaining the pathogenesis of leukemia as well as developing targeted therapies. Here, we provide an overview of the role of Ikaros tumor suppressor and its role in regulation of gene transcription in acute leukemia. Ikaros (IKZF1) is a DNA-binding protein that functions as a master regulator of hematopoiesis and the immune system, as well as a tumor suppressor in acute lymphoblastic leukemia (ALL). Genetic alteration or functional inactivation of Ikaros results in the development of high-risk leukemia. Ikaros binds to the specific consensus binding motif at upstream regulatory elements of its target genes, recruits chromatin-remodeling complexes and activates or represses transcription via chromatin remodeling. Over the last twenty years, a large number of Ikaros target genes have been identified, and the role of Ikaros in the regulation of their expression provided insight into the mechanisms of Ikaros tumor suppressor function in leukemia. Here we summarize the role of Ikaros in the regulation of the expression of the genes whose function is critical for cellular proliferation, development, and progression of acute lymphoblastic leukemia.
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29
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Guo W, Xing Y, Zhang Q, Xie J, Huang D, Gu H, He P, Zhou M, Xu S, Pang X, Liu M, Yi Z, Chen Y. Synthesis and Biological Evaluation of B-Cell Lymphoma 6 Inhibitors of N-Phenyl-4-pyrimidinamine Derivatives Bearing Potent Activities against Tumor Growth. J Med Chem 2020; 63:676-695. [PMID: 31895575 DOI: 10.1021/acs.jmedchem.9b01618] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The transcriptional repressor B-cell lymphoma 6 (BCL6) is frequently misregulated in diffuse large B-cell lymphoma (DLBCL) and has emerged as an attractive drug target for the treatments of lymphoma. In this article, a series of N-phenyl-4-pyrimidinamine derivatives were designed and synthesized as potent BCL6 inhibitors by optimizing hit compound N4-(3-chloro-4-methoxyphenyl)-N2-isobutyl-5-fluoro-2,4-pyrimidinediamine on the basis of the structure-activity relationship. Among them, compound 14j displayed the most potent activities, which significantly blocked the interaction of BCL6 with its corepressors, reactivated BCL6 target genes in a dose-dependent manner, and had better effects compared with the two positive controls. Further studies indicated that a low dose of 14j could effectively inhibit germinal center formation. More importantly, 14j not only showed potent inhibition of DLBCL cell proliferation in vitro but also strongly suppressed the growth of DLBCL in vivo.
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Affiliation(s)
- Weikai Guo
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Yajing Xing
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Qiansen Zhang
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Jiuqing Xie
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Dongxia Huang
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Haijun Gu
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Peng He
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Miaoran Zhou
- Shanghai University of Traditional Chinese Medicine , Shanghai 200030 , China
| | - Shifen Xu
- Shanghai University of Traditional Chinese Medicine , Shanghai 200030 , China
| | - Xiufeng Pang
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Mingyao Liu
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Zhengfang Yi
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
| | - Yihua Chen
- East China Normal University and Shanghai Fengxian District Central Hospital Joint Center for Translational Medicine, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences , East China Normal University , 200241 Shanghai , China
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Wu WR, Lin JT, Pan CT, Chan TC, Liu CL, Wu WJ, Sheu JJC, Yeh BW, Huang SK, Jhung JY, Hsiao MS, Li CF, Shiue YL. Amplification-driven BCL6-suppressed cytostasis is mediated by transrepression of FOXO3 and post-translational modifications of FOXO3 in urinary bladder urothelial carcinoma. Am J Cancer Res 2020; 10:707-724. [PMID: 31903146 PMCID: PMC6929993 DOI: 10.7150/thno.39018] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 10/17/2019] [Indexed: 01/14/2023] Open
Abstract
Muscle-invasive urinary bladder urothelial carcinoma (UBUC) is a lethal disease for which effective prognostic markers and potential therapy targets are still lacking. Previous array comparative genomic hybridization identified that 3q27 is frequently amplified in muscle-invasive UBUCs, one candidate proto-oncogene, B-cell CLL/lymphoma 6 (BCL6), mapped to this region. We therefore aimed to explore its downstream targets and physiological roles in UBUC progression. Methods: Specimens from UBUC patients, NOD/SCID mice and several UBUC-derived cell lines were used to perform quantitative RT-PCR, fluorescence in situ hybridization immunohistochemistry, xenograft, gene stable overexpression/knockdown and a series of in vitro experiments. Results: Amplification of the BCL6 gene lead to upregulation of BCL6 mRNA and protein levels in a substantial set of advanced UBUCs. High BCL6 protein level significantly predicted poor disease-specific and metastasis-free survivals. Knockdown of the BCL6 gene in J82 cells inhibited tumor growth and enhanced apoptosis in the NOD/SCID xenograft model. In vitro experiments demonstrated that BCL6 inhibited cytostasis, induced cell migration, invasion along with alteration of the expression levels of several related regulators. At molecular level, BCL6 inhibited forkhead box O3 (FOXO3) transcription, subsequent translation and upregulation of phosphorylated/inactive FOXO3 through phosphoinositide 3-kinase (PI3K)/AKT serine/threonine kinase (AKT) and/or epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase 1/2 (MAP2K1/2) signaling pathway(s). Two BCL6 binding sites on the proximal promoter region of the FOXO3 gene were confirmed. Conclusion: Overexpression of BCL6 served a poor prognostic factor in UBUC patients. In vivo and in vitro studies suggested that BCL6 functions as an oncogene through direct transrepression of the FOXO3 gene, downregulation and phosphorylation of the FOXO3 protein.
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Muselli F, Peyron JF, Mary D. Druggable Biochemical Pathways and Potential Therapeutic Alternatives to Target Leukemic Stem Cells and Eliminate the Residual Disease in Chronic Myeloid Leukemia. Int J Mol Sci 2019; 20:E5616. [PMID: 31717629 PMCID: PMC6888542 DOI: 10.3390/ijms20225616] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/06/2019] [Accepted: 11/07/2019] [Indexed: 12/14/2022] Open
Abstract
Chronic Myeloid Leukemia (CML) is a disease arising in stem cells expressing the BCR-ABL oncogenic tyrosine kinase that transforms one Hematopoietic stem/progenitor Cell into a Leukemic Stem Cell (LSC) at the origin of differentiated and proliferating leukemic cells in the bone marrow (BM). CML-LSCs are recognized as being responsible for resistances and relapses that occur despite the advent of BCR-ABL-targeting therapies with Tyrosine Kinase Inhibitors (TKIs). LSCs share a lot of functional properties with Hematopoietic Stem Cells (HSCs) although some phenotypical and functional differences have been described during the last two decades. Subverted mechanisms affecting epigenetic processes, apoptosis, autophagy and more recently metabolism and immunology in the bone marrow microenvironment (BMM) have been reported. The aim of this review is to bring together the modifications and molecular mechanisms that are known to account for TKI resistance in primary CML-LSCs and to focus on the potential solutions that can circumvent these resistances, in particular those that have been, or will be tested in clinical trials.
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MESH Headings
- Fusion Proteins, bcr-abl/antagonists & inhibitors
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Neoplasm, Residual/drug therapy
- Neoplasm, Residual/metabolism
- Neoplasm, Residual/pathology
- Neoplastic Stem Cells/drug effects
- Neoplastic Stem Cells/metabolism
- Neoplastic Stem Cells/pathology
- Protein Kinase Inhibitors/therapeutic use
- Tumor Microenvironment/drug effects
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Affiliation(s)
| | | | - Didier Mary
- Université Côte d’Azur, Institut National de la Santé et de la Recherche Médicale (Inserm) U1065, Centre Méditerranéen de Médecine Moléculaire, CEDEX 3, 06204 Nice, France; (F.M.); (J.-F.P.)
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A drug library screen identifies Carbenoxolone as novel FOXO inhibitor that overcomes FOXO3-mediated chemoprotection in high-stage neuroblastoma. Oncogene 2019; 39:1080-1097. [PMID: 31591479 PMCID: PMC6989399 DOI: 10.1038/s41388-019-1044-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 09/18/2019] [Accepted: 09/24/2019] [Indexed: 02/08/2023]
Abstract
The transcription factor FOXO3 has been associated in different tumor entities with hallmarks of cancer, including metastasis, tumor angiogenesis, maintenance of tumor-initiating stem cells, and drug resistance. In neuroblastoma (NB), we recently demonstrated that nuclear FOXO3 promotes tumor angiogenesis in vivo and chemoresistance in vitro. Hence, inhibiting the transcriptional activity of FOXO3 is a promising therapeutic strategy. However, as no FOXO3 inhibitor is clinically available to date, we used a medium-throughput fluorescence polarization assay (FPA) screening in a drug-repositioning approach to identify compounds that bind to the FOXO3-DNA-binding-domain (DBD). Carbenoxolone (CBX), a glycyrrhetinic acid derivative, was identified as a potential FOXO3-inhibitory compound that binds to the FOXO3-DBD with a binding affinity of 19 µM. Specific interaction of CBX with the FOXO3-DBD was validated by fluorescence-based electrophoretic mobility shift assay (FAM-EMSA). CBX inhibits the transcriptional activity of FOXO3 target genes, as determined by chromatin immunoprecipitation (ChIP), DEPP-, and BIM promoter reporter assays, and real-time RT-PCR analyses. In high-stage NB cells with functional TP53, FOXO3 triggers the expression of SESN3, which increases chemoprotection and cell survival. Importantly, FOXO3 inhibition by CBX treatment at pharmacologically relevant concentrations efficiently repressed FOXO3-mediated SESN3 expression and clonogenic survival and sensitized high-stage NB cells to chemotherapy in a 2D and 3D culture model. Thus, CBX might be a promising novel candidate for the treatment of therapy-resistant high-stage NB and other "FOXO-resistant" cancers.
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Li H, Liu L, Zhuang J, Liu C, Zhou C, Yang J, Gao C, Liu G, Sun C. Identification of key candidate targets and pathways for the targeted treatment of leukemia stem cells of chronic myelogenous leukemia using bioinformatics analysis. Mol Genet Genomic Med 2019; 7:e851. [PMID: 31373443 PMCID: PMC6732304 DOI: 10.1002/mgg3.851] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/20/2019] [Accepted: 06/24/2019] [Indexed: 12/27/2022] Open
Abstract
Background Chronic myelogenous leukemia (CML) is a myeloproliferative neoplasm that arises from the acquisition of constitutively active BCR‐ABL tyrosine kinase in hematopoietic stem cells. The persistence of bone marrow leukemia stem cells (LSCs) is the main cause of TKI resistance and CML relapse. Therefore, finding a key target or pathway to selectively target LSCs is of great significance for the thorough treatment of CML. Methods In this study, we aimed to identify key microRNAs, microRNA targets and pathways for the treatment of CML LSCs by integrating analyses of three microarray data profiles. We identified 51 differentially expressed microRNAs through integrated analysis of GSE90773 and performed functional gene predictions for microRNAs. Then, GSE11889 and GSE11675 were integrated to obtain differentially expressed genes (DEGs), and the overlapping DEGs were used as models to identify predictive functional genes. Finally, we identified 116 predictive functional genes. Clustering and significant enrichment analysis of 116 genes was based on function and signaling pathways. Subsequently, a protein interaction network was constructed, and module analysis and topology analysis were performed on the network. Results A total of 11 key candidate targets and 33 corresponding microRNAs were identified. The key pathways were mainly concentrated on the PI3K/AKT, Ras, JAK/STAT, FoxO and Notch signaling pathways. We also found that LSCs negatively regulated endogenous and exogenous apoptotic pathways to escape from apoptosis. Conclusion We identified key candidate targets and pathways for CML LSCs through bioinformatics methods, which improves our understanding of the molecular mechanisms of CML LSCs. These candidate genes and pathways may be therapeutic targets for CML LSCs.
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Affiliation(s)
- Huayao Li
- College of Basic medical, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, PR China
| | - Lijuan Liu
- College of First Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, PR China.,Department of Oncology, Affilited Hospital of Weifang Medical University, Weifang, Shandong, PR China
| | - Jing Zhuang
- Department of Oncology, Affilited Hospital of Weifang Medical University, Weifang, Shandong, PR China.,Department of Oncology, Weifang Traditional Chinese Hospital, Weifang, Shandong, PR China
| | - Cun Liu
- College of First Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, PR China
| | - Chao Zhou
- Department of Oncology, Affilited Hospital of Weifang Medical University, Weifang, Shandong, PR China.,Department of Oncology, Weifang Traditional Chinese Hospital, Weifang, Shandong, PR China
| | - Jing Yang
- Department of Oncology, Affilited Hospital of Weifang Medical University, Weifang, Shandong, PR China.,Department of Oncology, Weifang Traditional Chinese Hospital, Weifang, Shandong, PR China
| | - Chundi Gao
- College of First Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, PR China
| | - Gongxi Liu
- Department of Oncology, Affilited Hospital of Weifang Medical University, Weifang, Shandong, PR China.,Department of Oncology, Weifang Traditional Chinese Hospital, Weifang, Shandong, PR China
| | - Changgang Sun
- Department of Oncology, Affilited Hospital of Weifang Medical University, Weifang, Shandong, PR China.,Department of Oncology, Weifang Traditional Chinese Hospital, Weifang, Shandong, PR China
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Bugler J, Kinstrie R, Scott MT, Vetrie D. Epigenetic Reprogramming and Emerging Epigenetic Therapies in CML. Front Cell Dev Biol 2019; 7:136. [PMID: 31380371 PMCID: PMC6652210 DOI: 10.3389/fcell.2019.00136] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/05/2019] [Indexed: 12/16/2022] Open
Abstract
Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder characterized by BCR-ABL1, an oncogenic fusion gene arising from the Philadelphia chromosome. The development of tyrosine kinase inhibitors (TKIs) to overcome the constitutive tyrosine kinase activity of the BCR-ABL protein has dramatically improved disease management and patient outcomes over the past 20 years. However, the majority of patients are not cured and developing novel therapeutic strategies that target epigenetic processes are a promising avenue to improve cure rates. A number of epigenetic mechanisms are altered or reprogrammed during the development and progression of CML, resulting in alterations in histone modifications, DNA methylation and dysregulation of the transcriptional machinery. In this review these epigenetic alterations are examined and the potential of epigenetic therapies are discussed as a means of eradicating residual disease and offering a potential cure for CML in combination with current therapies.
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Affiliation(s)
| | | | | | - David Vetrie
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
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35
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Herrmann O, Kuepper MK, Bütow M, Costa IG, Appelmann I, Beier F, Luedde T, Braunschweig T, Koschmieder S, Brümmendorf TH, Schemionek M. Infliximab therapy together with tyrosine kinase inhibition targets leukemic stem cells in chronic myeloid leukemia. BMC Cancer 2019; 19:658. [PMID: 31272418 PMCID: PMC6610865 DOI: 10.1186/s12885-019-5871-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/24/2019] [Indexed: 01/17/2023] Open
Abstract
Background Expression of Bcr-Abl in hematopoietic stem cells is sufficient to cause chronic myeloid leukemia (CML) and tyrosine kinase inhibitors (TKI) induce molecular remission in the majority of CML patients. However, the disease driving stem cell population is not fully targeted by TKI therapy, and leukemic stem cells (LSC) capable of re-inducing the disease can persist. Single-cell RNA-sequencing technology recently identified an enriched inflammatory gene signature with TNFα and TGFβ being activated in TKI persisting quiescent LSC. Here, we studied the effects of human TNFα antibody infliximab (IFX), which has been shown to induce anti-inflammatory effects in mice, combined with TKI treatment on LSC function. Methods We first performed GSEA-pathway analysis using our microarray data of murine LSK cells (lin−; Sca-1+; c-kit+) from the SCLtTA/Bcr-Abl CML transgenic mouse model. Bcr-Abl positive cell lines were generated by retroviral transduction. Clonogenic potential was assessed by CFU (colony forming unit). CML mice were treated with nilotinib or nilotinib plus infliximab, and serial transplantation experiments were performed. Results Likewise to human CML, TNFα signaling was specifically active in murine CML stem cells, and ectopic expression of Bcr-Abl in murine and human progenitor cell lines induced TNFα expression. In vitro exposure to human (IFX) or murine (MP6-XT22) TNFα antibody reduced clonogenic growth of CML cells. Interestingly, TNFα antibody treatment enhanced TKI-induced effects on immature cells in vitro. Additionally, in transplant and serial transplant experiments, using our transgenic CML mouse model, we could subsequently show that IFX therapy boosted TKI-induced effects and further reduced the proportion of malignant stem cells in vivo. Conclusion TNFα signaling is induced in CML stem cells, and anti-inflammatory therapy enhances TKI-induced decline of LSC, confirming that successful targeting of persisting CML stem cells can be enhanced by addressing their malignant microenvironment simultaneously. Electronic supplementary material The online version of this article (10.1186/s12885-019-5871-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Oliver Herrmann
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Maja Kim Kuepper
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Marlena Bütow
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Ivan G Costa
- IZKF Research Group Bioinformatics Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany
| | - Iris Appelmann
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Fabian Beier
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Tom Luedde
- Department of Medicine III, University Hospital RWTH Aachen, Aachen, Germany
| | - Till Braunschweig
- Department of Pathology, University Hospital RWTH Aachen, Aachen, Germany
| | - Steffen Koschmieder
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Tim H Brümmendorf
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany
| | - Mirle Schemionek
- Department of Hematology Oncology Hemostaseology and Stem Cell Transplantation Faculty of Medicine, University Hospital RWTH Aachen, Pauwelsstr 30, 52074, Aachen, Germany.
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Prosurvival kinase PIM2 is a therapeutic target for eradication of chronic myeloid leukemia stem cells. Proc Natl Acad Sci U S A 2019; 116:10482-10487. [PMID: 31068472 DOI: 10.1073/pnas.1903550116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A major obstacle to curing chronic myeloid leukemia (CML) is the intrinsic resistance of CML stem cells (CMLSCs) to the drug imatinib mesylate (IM). Prosurvival genes that are preferentially expressed in CMLSCs compared with normal hematopoietic stem cells (HSCs) represent potential therapeutic targets for selectively eradicating CMLSCs. However, the discovery of such preferentially expressed genes has been hampered by the inability to completely separate CMLSCs from HSCs, which display a very similar set of surface markers. To overcome this challenge, and to minimize confounding effects of individual differences in gene expression profiles, we performed single-cell RNA-seq on CMLSCs and HSCs that were isolated from the same patient and distinguished based on the presence or absence of BCR-ABL. Among genes preferentially expressed in CMLSCs is PIM2, which encodes a prosurvival serine-threonine kinase that phosphorylates and inhibits the proapoptotic protein BAD. We show that IM resistance of CMLSCs is due, at least in part, to maintenance of BAD phosphorylation by PIM2. We find that in CMLSCs, PIM2 expression is promoted by both a BCR-ABL-dependent (IM-sensitive) STAT5-mediated pathway and a BCR-ABL-independent (IM-resistant) STAT4-mediated pathway. Combined treatment with IM and a PIM inhibitor synergistically increases apoptosis of CMLSCs, suppresses colony formation, and significantly prolongs survival in a mouse CML model, with a negligible effect on HSCs. Our results reveal a therapeutically targetable mechanism of IM resistance in CMLSCs. The experimental approach that we describe can be generally applied to other malignancies that harbor oncogenic fusion proteins or other characteristic genetic markers.
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Zhang H, Li S. Concise Review: Exploiting Unique Biological Features of Leukemia Stem Cells for Therapeutic Benefit. Stem Cells Transl Med 2019; 8:768-774. [PMID: 31016860 PMCID: PMC6646691 DOI: 10.1002/sctm.18-0247] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 03/15/2019] [Indexed: 12/19/2022] Open
Abstract
Cancer stem cells play a critical role in disease initiation and insensitivity to chemotherapy in numerous hematologic malignancies and some solid tumors, and these stem cells need to be eradicated to achieve a cure. Key to successful targeting of cancer stem cells is to identify and functionally test critical target genes and to fully understand their associated molecular network in these stem cells. Human chronic myeloid leukemia (CML) is well accepted as one of the typical types of hematopoietic malignancies that are derived from leukemia stem cells (LSCs), serving as an excellent model disease for understanding the biology of LSCs and developing effective, selective, and curative strategies through targeting LSCs. Here, we discuss LSCs in CML with a focus on identification of unique biological features of these stem cells to emphasize the feasibility and significance of specific targeting of LSCs while sparing normal stem cell counterparts in leukemia therapy. stem cells translational medicine2019;8:768&774
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Affiliation(s)
- Haojian Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology, Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, People's Republic of China
| | - Shaoguang Li
- Division of Hematology/Oncology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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38
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Kellner J, Wallace C, Liu B, Li Z. Definition of a multiple myeloma progenitor population in mice driven by enforced expression of XBP1s. JCI Insight 2019; 4:124698. [PMID: 30944260 DOI: 10.1172/jci.insight.124698] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 02/19/2019] [Indexed: 12/20/2022] Open
Abstract
Multiple myeloma (MM) is an incurable plasma cell malignancy with frequent treatment failures and relapses, suggesting the existence of pathogenic myeloma stem/progenitor populations. However, the identity of MM stem cells remains elusive. We used a murine model of MM with transgenic overexpression of the unfolded protein response sensor X-box binding protein 1 (XBP1s) in the B cell compartment to define MM stem cells. We herein report that a post-germinal center, pre-plasma cell population significantly expands as MM develops. This population has the following characteristics: (a) cell surface phenotype of B220+CD19+IgM-IgD-CD138-CD80+sIgG-AA4.1+FSChi; (b) high expression levels of Pax5 and Bcl6 with intermediate levels of Blimp1 and XBP1s; (c) increased expression of aldehyde dehydrogenase, Notch1, and c-Kit; and (d) ability to efficiently reconstitute antibody-producing capacity in B cell-deficient mice in vivo. We thus have defined a plasma cell progenitor population that resembles myeloma stem cells in mice. These results provide potentially novel insights into MM stem cell biology and may contribute to the development of novel stem cell-targeted therapies for the eradication of MM.
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Affiliation(s)
| | | | - Bei Liu
- Department of Microbiology and Immunology and.,Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Zihai Li
- Department of Microbiology and Immunology and.,Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, USA.,First Affiliated Hospital, Zhengzhou University School of Medicine, Zhengzhou, China
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39
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Liu Q, Zhang Y, Wang P, Liu J, Li B, Yu Y, Wu H, Kang R, Zhang X, Wang Z. Deciphering the scalene association among type-2 diabetes mellitus, prostate cancer, and chronic myeloid leukemia via enrichment analysis of disease-gene network. Cancer Med 2019; 8:2268-2277. [PMID: 30938105 PMCID: PMC6536925 DOI: 10.1002/cam4.1845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 09/25/2018] [Accepted: 10/06/2018] [Indexed: 12/12/2022] Open
Abstract
The potential biological relationship between type‐2 diabetes mellitus (T2DM) has been focused in numerous studies. To investigate the molecular associations among T2DM, prostate cancer (PCa), and chronic myeloid leukemia (CML), using a biomolecular network enrichment analysis. We obtained a list of disease‐related genes and constructed disease networks. Then, GO enrichment analysis was performed to identify the significant functions and pathways of overlapping modules in the Database for Annotation, Visualization and Integrated Discovery (DAVID) database. More than 75% of these overlapping genes were found to be consistent with the findings of previous studies. In the three diseases, we found that Sarcoglycan delta (SGCD) and Rho family GTPase 3 (RND3) were the overlapping genes and identified negative regulation of apoptotic process and negative regulation of transcription from RNA polymerase II promoter RNA as the two overlapping biological functions. CML and PCa were the most closely related, with 34 overlapping genes, five overlapping modules, 27 overlapping biological functions, and nine overlapping pathways. There were 13 overlapping genes, one overlapping modules, four overlapping biological functions and one overlapping pathway (FoxO signaling pathway) were found in T2DM and CML.And T2DM and PCa were the least related pair in our study, with only six overlapping genes, five overlapping modules, and one overlapping biological function. SGCD and RND3 were the main gene‐to‐gene relationship among T2DM, CML, and PCa; apoptosis, development, and transcription from RNA polymerase II promote processes were the main functional connections among T2DM, CML, and PCa by network enrichment analysis. There is a “scalene” relationship among T2DM, CML, and PCa at gene, pathway, biological process, and module levels: CML and PCa were the most closely related, the second were T2DM and PCa, and T2DM and PCa were the least related pair in our study. Our study provides a new avenue for further studies on T2DM and cancers, which may promote the discovery and development of novel therapeutic and can be used to treat multiple diseases.
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Affiliation(s)
- Qiong Liu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yingying Zhang
- Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Pengqian Wang
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jun Liu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
| | - Bing Li
- Institute of Information on Traditional Chinese Medicine, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yanan Yu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
| | - Hongli Wu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ruixia Kang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xiaoxu Zhang
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Zhong Wang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, China
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40
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Reshef YA, Finucane HK, Kelley DR, Gusev A, Kotliar D, Ulirsch JC, Hormozdiari F, Nasser J, O'Connor L, van de Geijn B, Loh PR, Grossman SR, Bhatia G, Gazal S, Palamara PF, Pinello L, Patterson N, Adams RP, Price AL. Detecting genome-wide directional effects of transcription factor binding on polygenic disease risk. Nat Genet 2018; 50:1483-1493. [PMID: 30177862 PMCID: PMC6202062 DOI: 10.1038/s41588-018-0196-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 07/11/2018] [Indexed: 12/19/2022]
Abstract
Biological interpretation of genome-wide association study data frequently involves assessing whether SNPs linked to a biological process, for example, binding of a transcription factor, show unsigned enrichment for disease signal. However, signed annotations quantifying whether each SNP allele promotes or hinders the biological process can enable stronger statements about disease mechanism. We introduce a method, signed linkage disequilibrium profile regression, for detecting genome-wide directional effects of signed functional annotations on disease risk. We validate the method via simulations and application to molecular quantitative trait loci in blood, recovering known transcriptional regulators. We apply the method to expression quantitative trait loci in 48 Genotype-Tissue Expression tissues, identifying 651 transcription factor-tissue associations including 30 with robust evidence of tissue specificity. We apply the method to 46 diseases and complex traits (average n = 290 K), identifying 77 annotation-trait associations representing 12 independent transcription factor-trait associations, and characterize the underlying transcriptional programs using gene-set enrichment analyses. Our results implicate new causal disease genes and new disease mechanisms.
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Affiliation(s)
- Yakir A Reshef
- Department of Computer Science, Harvard University, Cambridge, MA, USA.
- Harvard/MIT MD/PhD Program, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
| | | | - David R Kelley
- California Life Sciences LLC, South San Francisco, CA, USA
| | | | - Dylan Kotliar
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jacob C Ulirsch
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Dana Farber Cancer Institute, Boston, MA, USA
- Boston Children's Hospital, Boston, MA, USA
| | - Farhad Hormozdiari
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Joseph Nasser
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Luke O'Connor
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Program in Bioinformatics and Integrative Genomics, Harvard University, Cambridge, MA, USA
| | - Bryce van de Geijn
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Po-Ru Loh
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Sharon R Grossman
- Harvard/MIT MD/PhD Program, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Gaurav Bhatia
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Steven Gazal
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Pier Francesco Palamara
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Statistics, University of Oxford, Oxford, UK
| | - Luca Pinello
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Massachusetts General Hospital, Charlestown, MA, USA
- Department of Pathology, Harvard Medical School, Boston, MA, USA
| | | | - Ryan P Adams
- Google Brain, New York, NY, USA
- Department of Computer Science, Princeton University, Princeton, NJ, USA
| | - Alkes L Price
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
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41
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Cheng H, Linhares BM, Yu W, Cardenas MG, Ai Y, Jiang W, Winkler A, Cohen S, Melnick A, MacKerell A, Cierpicki T, Xue F. Identification of Thiourea-Based Inhibitors of the B-Cell Lymphoma 6 BTB Domain via NMR-Based Fragment Screening and Computer-Aided Drug Design. J Med Chem 2018; 61:7573-7588. [PMID: 29969259 PMCID: PMC6334293 DOI: 10.1021/acs.jmedchem.8b00040] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Protein-protein interactions (PPI) between the transcriptional repressor B-cell lymphoma 6 (BCL6) BTB domain (BCL6BTB) and its corepressors have emerged as a promising target for anticancer therapeutics. However, identification of potent, drug-like inhibitors of BCL6BTB has remained challenging. Using NMR-based screening of a library of fragment-like small molecules, we have identified a thiourea compound (7CC5) that binds to BCL6BTB. From this hit, the application of computer-aided drug design (CADD), medicinal chemistry, NMR spectroscopy, and X-ray crystallography has yielded an inhibitor, 15f, that demonstrated over 100-fold improved potency for BCL6BTB. This gain in potency was achieved by a unique binding mode that mimics the binding mode of the corepressor SMRT in the aromatic and the HDCH sites. The structure-activity relationship based on these new inhibitors will have a significant impact on the rational design of novel BCL6 inhibitors, facilitating the identification of therapeutics for the treatment of BCL6-dependent tumors.
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Affiliation(s)
- Huimin Cheng
- University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, 21201, USA
| | - Brian M. Linhares
- University of Michigan, Department of Pathology, Ann Arbor, Michigan, 48109, USA
| | - Wenbo Yu
- University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, 21201, USA,University of Maryland Computer-Aided Drug Design Center, Baltimore, Maryland, 21201, USA
| | - Mariano G. Cardenas
- Weill Cornell Medical College, Department of Hematology/Oncology, New York, New York, 10021, USA
| | - Yong Ai
- University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, 21201, USA
| | - Wenjuan Jiang
- University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, 21201, USA,University of Maryland Computer-Aided Drug Design Center, Baltimore, Maryland, 21201, USA
| | - Alyssa Winkler
- University of Michigan, Department of Pathology, Ann Arbor, Michigan, 48109, USA
| | - Sandra Cohen
- Weill Cornell Medical College, Department of Hematology/Oncology, New York, New York, 10021, USA
| | - Ari Melnick
- Weill Cornell Medical College, Department of Hematology/Oncology, New York, New York, 10021, USA
| | - Alexander MacKerell
- University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, 21201, USA,University of Maryland Computer-Aided Drug Design Center, Baltimore, Maryland, 21201, USA
| | - Tomasz Cierpicki
- University of Michigan, Department of Pathology, Ann Arbor, Michigan, 48109, USA,Correspondence to: Professor Fengtian Xue at the Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, Maryland 21201, USA, Phone: 410-706-8521, , Professor Tomasz Cierpicki at the University of Michigan, Department of Pathology, Ann Arbor, Michigan 48109, USA, Phone: 734-615-9324,
| | - Fengtian Xue
- University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, 21201, USA,University of Maryland Computer-Aided Drug Design Center, Baltimore, Maryland, 21201, USA,Correspondence to: Professor Fengtian Xue at the Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, Maryland 21201, USA, Phone: 410-706-8521, , Professor Tomasz Cierpicki at the University of Michigan, Department of Pathology, Ann Arbor, Michigan 48109, USA, Phone: 734-615-9324,
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Deacetylase activity-independent transcriptional activation by HDAC2 during TPA-induced HL-60 cell differentiation. PLoS One 2018; 13:e0202935. [PMID: 30142192 PMCID: PMC6108480 DOI: 10.1371/journal.pone.0202935] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/10/2018] [Indexed: 12/22/2022] Open
Abstract
The human myeloid leukemia cell line HL-60 differentiate into monocytes following treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA). However, the mechanism underlying the differentiation of these cells in response to TPA has not been fully elucidated. In this study, we performed ChIP-seq profiling of RNA Pol II, HDAC2, Acetyl H3 (AcH3), and H3K27me3 and analyzed differential chromatin state changes during TPA-induced differentiation of HL-60 cells. We focused on atypically active genes, which showed enhanced H3 acetylation despite increased HDAC2 recruitment. We found that HDAC2 positively regulates the expression of these genes in a histone deacetylase activity-independent manner. HDAC2 interacted with and recruited paired box 5 (PAX5) to the promoters of the target genes and regulated HL-60 cell differentiation by PAX5-mediated gene activation. Taken together, these data elucidated the specific-chromatin status during HL-60 cell differentiation following TPA exposure and suggested that HDAC2 can activate transcription of certain genes through interactions with PAX5 in a deacetylase activity-independent pathway.
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Hornsveld M, Dansen T, Derksen P, Burgering B. Re-evaluating the role of FOXOs in cancer. Semin Cancer Biol 2018; 50:90-100. [DOI: 10.1016/j.semcancer.2017.11.017] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/23/2017] [Accepted: 11/20/2017] [Indexed: 02/07/2023]
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Ujvari D, Nagy N, Madapura HS, Kallas T, Kröhnke MCL, Stenke L, Klein E, Salamon D. Interferon γ is a strong, STAT1-dependent direct inducer of BCL6 expression in multiple myeloma cells. Biochem Biophys Res Commun 2018; 498:502-508. [PMID: 29510136 DOI: 10.1016/j.bbrc.2018.03.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 03/02/2018] [Indexed: 01/10/2023]
Abstract
B-cell CLL/lymphoma 6 (BCL6) is a transcriptional master regulator that can repress more than 1200 potential target genes. It exerts oncogenic effects through the inhibition of differentiation, DNA damage sensing and apoptosis in several human hematopoietic malignancies, including multiple myeloma (MM). The multifunctional cytokine interferon γ (IFNγ) exerts pro-apoptotic and anti-proliferative effects on MM cells in vitro, at least partially through the inhibition of the effects of interleukin 6 (IL6), one of the most important growth factor of MM and a strong inducer of BCL6 expression. However, IFNγ was also reported to directly upregulate BCL6 in several cell types. These observations prompted us to analyze the effect of IFNγ on BCL6 expression in MM cells. We discovered that among several myeloma growth/survival factors tested (including IL6, oncostatin M, insulin-like growth factor 1, tumor necrosis factor α and IFNα) IFNγ was the strongest inducer of BCL6 mRNA and protein expression in MM cell lines. IFNγ induced upregulation of BCL6 was dependent on the classical STAT1 signaling pathway, and affected both major BCL6 variants. Interestingly, although IFNα induced stronger STAT1 phosphorylation than IFNγ, it only slightly upregulated BCL6 in MM lines. We proved that IFNα induced BCL6 upregulation was limited by the concomitant activation of STAT5 signaling. We assume that BCL6 upregulation may represent a potentially pro-tumorigenic effect of IFNγ signaling in MM cells.
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Affiliation(s)
- Dorina Ujvari
- Department of Women`s and Children`s Health, Karolinska Institutet, Stockholm, Sweden
| | - Noemi Nagy
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Harsha S Madapura
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Tomasz Kallas
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Marijke C L Kröhnke
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Leif Stenke
- Department of Medicine, Division of Hematology, Karolinska University Hospital Solna and Karolinska Institutet, Stockholm, Sweden
| | - Eva Klein
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Daniel Salamon
- Department of Women`s and Children`s Health, Karolinska Institutet, Stockholm, Sweden; Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
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45
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Tijchon E, van Emst L, Yuniati L, van Ingen Schenau D, Gerritsen M, van der Meer LT, Williams O, Hoogerbrugge PM, Scheijen B, van Leeuwen FN. Tumor suppressor BTG1 limits activation of BCL6 expression downstream of ETV6-RUNX1. Exp Hematol 2018; 60:57-62.e3. [PMID: 29408281 DOI: 10.1016/j.exphem.2018.01.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/10/2018] [Accepted: 01/20/2018] [Indexed: 11/28/2022]
Abstract
Translocation t(12;21) (p13;q22), giving rise to the ETV6-RUNX1 fusion gene, is the most common genetic abnormality in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). This translocation usually arises in utero, but its expression is insufficient to induce leukemia and requires other cooperating genetic lesions for BCP-ALL to develop. Deletions affecting the transcriptional coregulator BTG1 are frequently observed in ETV6-RUNX1-positive leukemia. Here we report that Btg1 deficiency enhances the self-renewal capacity of ETV6-RUNX1-positive mouse fetal liver-derived hematopoietic progenitors (FL-HPCs). Combined expression of the fusion protein and a loss of BTG1 drive upregulation of the proto-oncogene Bcl6 and downregulation of BCL6 target genes, such as p19Arf and Tp53. Similarly, ectopic expression of BCL6 promotes the self-renewal and clonogenic replating capacity of FL-HPCs, by suppressing the expression of p19Arf and Tp53. Together these results identify BCL6 as a potential driver of ETV6-RUNX1-mediated leukemogenesis, which could involve loss of BTG1-dependent suppression of ETV6-RUNX1 function.
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Affiliation(s)
- Esther Tijchon
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Liesbeth van Emst
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Laurensia Yuniati
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | | | - Mylène Gerritsen
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Laurens T van der Meer
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Owen Williams
- Molecular Haematology and Cancer Biology Unit, UCL-Institute of Child Health, London, United Kingdom
| | | | - Blanca Scheijen
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Frank N van Leeuwen
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, The Netherlands.
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46
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Wang Q, Ding W, Ding Y, Ma J, Qian Z, Shao J, Li Y. Homoharringtonine suppresses imatinib resistance via the Bcl-6/p53 pathway in chronic myeloid leukemia cell lines. Oncotarget 2018; 8:37594-37604. [PMID: 28410239 PMCID: PMC5514933 DOI: 10.18632/oncotarget.16731] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 03/08/2017] [Indexed: 11/25/2022] Open
Abstract
Background The anti-leukemic mechanism of homoharringtonine (HHT) differs from that of IM, and HHT is one of the most useful agents for use in patients with IM resistance or intolerance. The Bcl-6/p53 pathway has been shown to regulate the sensitivity of tumor cells to antitumor drugs. We tested whether HHT blocked the Bcl-6/p53 pathway in order to promote the apoptosis of IM-resistant cells in vitro and in vivo. Results Ph+ acute lymphoblastic leukemia (ALL) cells and IM-resistant chronic myeloid leukemia (CML) cells showed high expression of Bcl-6 protein. Bcl-6 mediated the upregulation of p53, and and Bcl-6 induced growth inhibition of IM-resistant cells as well as its apoptosis by targeting p53. In addition, Bcl-6 was downregulated moderately after HHT treatment in different cells. The Bcl-6 expression was significantly increased in patients with CML when compared with healthy subjects. Furthermore, the expression of Bcl-6 was higher in patients with CML-blastic phase (CML-BP) than in those with CML-chronic phase (CML-CP). Methods The inhibitory effect of drugs on cell growth was detected by Cell Counting Kit-8 (CCK-8), The apoptosis rate and the cell cycle were investigated by flow cytometry. The expression of Bcl-6, p53, Bcl-2, caspase9, and caspase3 proteins was assayed by western blot, Real- Time PCR (qPCR) detect Bcl-6 and p53 mRNA. Conclusions HHT can suppress the growth and induce apoptosis of IM-resistant cells, the mechanism of which is associated with blocking of the Bcl-6/p53 pathway. Our results could offer a theoretical explanation for HHT use in patients with IM resistance or intolerance.
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Affiliation(s)
- Qian Wang
- Department of Hematology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
| | - Wei Ding
- Department of Hematology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
| | - Yihan Ding
- Department of Hematology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
| | - Jingjing Ma
- Department of Hematology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
| | - Zhaoye Qian
- Department of Oncology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
| | - Jingxian Shao
- Department of Oncology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
| | - Yufeng Li
- Department of Hematology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an, 223300, China
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47
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Alferez DG, Simões BM, Howell SJ, Clarke RB. The Role of Steroid Hormones in Breast and Effects on Cancer Stem Cells. CURRENT STEM CELL REPORTS 2018; 4:81-94. [PMID: 29600163 PMCID: PMC5866269 DOI: 10.1007/s40778-018-0114-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Purpose of Review This review will discuss how the steroid hormones, estrogen and progesterone, as well as treatments that target steroid receptors, can regulate cancer stem cell (CSC) activity. The CSC theory proposes a hierarchical organization in tumors where at its apex lies a subpopulation of cancer cells endowed with self-renewal and differentiation capacity. Recent Findings In breast cancer (BC), CSCs have been suggested to play a key role in tumor maintenance, disease progression, and the formation of metastases. In preclinical models of BC, only a few CSCs are required sustain tumor re-growth, especially after conventional anti-endocrine treatments. CSCs include therapy-resistant clones that survive standard of care treatments like chemotherapy, irradiation, and hormonal therapy. Summary The relevance of hormones for both normal mammary gland and BC development is well described, but it was only recently that the activities of hormones on CSCs have been investigated, opening new directions for future BC treatments and CSCs.
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Affiliation(s)
- Denis G. Alferez
- Breast Biology Group, Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine, and Health, Manchester Cancer Research Centre, Wilmslow Road, Manchester, M20 4GJ UK
| | - Bruno M. Simões
- Breast Biology Group, Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine, and Health, Manchester Cancer Research Centre, Wilmslow Road, Manchester, M20 4GJ UK
| | - Sacha J. Howell
- Breast Biology Group, Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine, and Health, Manchester Cancer Research Centre, Wilmslow Road, Manchester, M20 4GJ UK
- Department of Medical Oncology, The University of Manchester, The Christie NHS Foundation Trust, Manchester, M20 4BX UK
| | - Robert B. Clarke
- Breast Biology Group, Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine, and Health, Manchester Cancer Research Centre, Wilmslow Road, Manchester, M20 4GJ UK
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48
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Ge Z, Zhou X, Gu Y, Han Q, Li J, Chen B, Ge Q, Dovat E, Payne JL, Sun T, Song C, Dovat S. Ikaros regulation of the BCL6/BACH2 axis and its clinical relevance in acute lymphoblastic leukemia. Oncotarget 2018; 8:8022-8034. [PMID: 28030830 PMCID: PMC5352379 DOI: 10.18632/oncotarget.14038] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/24/2016] [Indexed: 12/27/2022] Open
Abstract
B-Cell CLL/Lymphoma 6 (BCL6) is a proto-oncogene that is highly expressed in acute lymphoblastic leukemia (ALL). BTB and CNC Homology 1 Basic Leucine Zipper Transcription Factor 2 (BACH2) is a suppressor of transcription. The BACH2-BCL6 balance controls selection at the pre-B cell receptor checkpoint by regulating p53 expression. However, the underlying mechanism and the clinical relevance of the BCL6/BACH2 axis are unknown. Here, we found that Ikaros, a tumor suppressor encoded by IKZF1, directly binds to both the BCL6 and BACH2 promoters where it suppresses BCL6 and promotes BACH2 expression in B-cell ALL (B-ALL) cells. Casein kinase 2 (CK2) inhibitors increase Ikaros function thereby inhibiting BCL6 and promoting BACH2 expression in an Ikaros-dependent manner. We also found that the expression of BCL6 is higher while BACH2 expression is lower in patients with B-ALL than normal bone marrow control. High BCL6 and low BACH2 expression is associated with high leukemic cell proliferation, unfavorable clinical and laboratory features, and inferior outcomes. Moreover, IKZF1 deletion is associated with high BCL6 and low BACH2 expression in B-ALL patients. CK2 inhibitors increase Ikaros binding to the promoter of BCL6 and BACH2 and suppress BCL6 while promoting BACH2 expression in the primary B-ALL cells. Our data indicates that Ikaros regulates expression of the BCL6/BACH2 axis in B-ALL. High BCL6 and low BACH2 expression are associated with Ikaros dysregulation and have a potential effect on the development of B-ALL.
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Affiliation(s)
- Zheng Ge
- Department of Hematology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China.,International Cooperative Leukemia Group and International Cooperative Laboratory of Hematology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China
| | - Xilian Zhou
- Department of Hematology, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing 210029, China
| | - Yan Gu
- Department of Hematology, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing 210029, China
| | - Qi Han
- Department of Hematology, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing 210029, China
| | - Jianyong Li
- Department of Hematology, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing 210029, China
| | - Baoan Chen
- Department of Hematology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China.,International Cooperative Leukemia Group and International Cooperative Laboratory of Hematology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China
| | - Qinyu Ge
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Elanora Dovat
- Department of Pediatrics, Pennsylvania State University Medical College, Hershey, PA 17033, USA
| | - Jonathon L Payne
- Department of Pediatrics, Pennsylvania State University Medical College, Hershey, PA 17033, USA.,Loma Linda University School of Medicine, Department of Basic Sciences, Loma Linda, CA 92350, USA
| | - Tianyu Sun
- Department of Internal Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Chunhua Song
- International Cooperative Leukemia Group and International Cooperative Laboratory of Hematology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China.,Department of Pediatrics, Pennsylvania State University Medical College, Hershey, PA 17033, USA
| | - Sinisa Dovat
- International Cooperative Leukemia Group and International Cooperative Laboratory of Hematology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China.,Department of Pediatrics, Pennsylvania State University Medical College, Hershey, PA 17033, USA
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49
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Arrigoni E, Del Re M, Galimberti S, Restante G, Rofi E, Crucitta S, Baratè C, Petrini M, Danesi R, Di Paolo A. Concise Review: Chronic Myeloid Leukemia: Stem Cell Niche and Response to Pharmacologic Treatment. Stem Cells Transl Med 2018; 7:305-314. [PMID: 29418079 PMCID: PMC5827745 DOI: 10.1002/sctm.17-0175] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 01/09/2018] [Indexed: 12/27/2022] Open
Abstract
Nowadays, more than 90% of patients affected by chronic myeloid leukemia (CML) survive with a good quality of life, thanks to the clinical efficacy of tyrosine kinase inhibitors (TKIs). Nevertheless, point mutations of the ABL1 pocket occurring during treatment may reduce binding of TKIs, being responsible of about 20% of cases of resistance among CML patients. In addition, the presence of leukemic stem cells (LSCs) represents the most important event in leukemia progression related to TKI resistance. LSCs express stem cell markers, including active efflux pumps and genetic and epigenetic alterations together with deregulated cell signaling pathways involved in self-renewal, such as Wnt/β-catenin, Notch, and Hedgehog. Moreover, the interaction with the bone marrow microenvironment, also known as hematopoietic niche, may influence the phenotype of surrounding cells, which evade mechanisms controlling cell proliferation and are less sensitive or frankly resistant to TKIs. This Review focuses on the role of LSCs and stem cell niche in relation to response to pharmacological treatments. A literature search from PubMed database was performed until April 30, 2017, and it has been analyzed according to keywords such as chronic myeloid leukemia, stem cell, leukemic stem cells, hematopoietic niche, tyrosine kinase inhibitors, and drug resistance. Stem Cells Translational Medicine 2018;7:305-314.
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Affiliation(s)
- Elena Arrigoni
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Marzia Del Re
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Sara Galimberti
- Unit of Hematology, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Giuliana Restante
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Eleonora Rofi
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Stefania Crucitta
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Claudia Baratè
- Unit of Hematology, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Mario Petrini
- Unit of Hematology, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Romano Danesi
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
| | - Antonello Di Paolo
- Unit of Clinical Pharmacology and Pharmacogenetics, Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly
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50
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Abstract
BCR-ABL1 tyrosine kinase inhibitors (TKIs) have improved the prognosis of chronic phase chronic myeloid leukemia (CP-CML) to an extent that survival is largely determined by non-CML mortality. Monitoring for minimal residual disease by measuring BCR-ABL1 messenger RNA is a key component of CML management. CP-CML patients who achieve a stable deep molecular response may discontinue (TKIs) with an ~ 50% chance of entering treatment-free remission (TFR). So far discontinuation of TKIs has largely been limited to clinical trials, but is on the verge of becoming a part of wider clinical practice. Careful patient selection, dense molecular monitoring, and prompt reinstitution of treatment in the event of relapse are all vital to reproduce the same level of success. Much effort has been dedicated to identifying therapeutic strategies to eliminate CML stem cells and enable to TFR in more patients. Unfortunately, despite promising preclinical data, as yet, none of the various approaches have entered clinical practice.
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