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Liang Y, Zhao J, Dai T, Li X, Chen L, He Z, Guo M, Zhao J, Xu L. A review of KLF4 and inflammatory disease: Current status and future perspective. Pharmacol Res 2024; 207:107345. [PMID: 39134187 DOI: 10.1016/j.phrs.2024.107345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 08/03/2024] [Accepted: 08/07/2024] [Indexed: 08/15/2024]
Abstract
Inflammation is the response of the human body to injury, infection, or other abnormal states, which is involved in the development of many diseases. As a member of the Krüppel-like transcription factors (KLFs) family, KLF4 plays a crucial regulatory role in physiological and pathological processes due to its unique dual domain of transcriptional activation and inhibition. A growing body of evidence has demonstrated that KLF4 plays a pivotal role in the pathogenesis of various inflammatory disorders, including inflammatory bowel disease, osteoarthritis, renal inflammation, pneumonia, neuroinflammation, and so on. Consequently, KLF4 has emerged as a promising new therapeutic target for inflammatory diseases. This review systematically generalizes the molecular regulatory network, specific functions, and mechanisms of KLF4 to elucidate its complex roles in inflammatory diseases. An in-depth study on the biological function of KLF4 is anticipated to offer a novel research perspective and potential intervention strategies for inflammatory diseases.
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Affiliation(s)
- Yidan Liang
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Jiamin Zhao
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Tengkun Dai
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Xin Li
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Longqin Chen
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Zhixu He
- Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Mengmeng Guo
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China.
| | - Juanjuan Zhao
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China.
| | - Lin Xu
- Special Key Laboratory of Gene Detection &Therapy of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou 563000, China; Department of Immunology, Zunyi Medical University, Zunyi, Guizhou 563000, China; Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, Guizhou 563000, China.
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2
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Cai S, Wang X, Xu R, Liang Z, Zhu Q, Chen M, Lin Z, Li C, Duo T, Tong X, Li E, He Z, Liu X, Chen Y, Mo D. KLF4 regulates skeletal muscle development and regeneration by directly targeting P57 and Myomixer. Cell Death Dis 2023; 14:612. [PMID: 37723138 PMCID: PMC10507053 DOI: 10.1038/s41419-023-06136-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 09/02/2023] [Accepted: 09/07/2023] [Indexed: 09/20/2023]
Abstract
Krüppel-like factor 4 (KLF4) is an evolutionarily conserved zinc finger-containing transcription factor that regulates diverse cellular processes such as cell proliferation, apoptosis, and differentiation. Our previous study showed that KLF4 expression is upregulated in skeletal muscle ontogeny during embryonic development in pigs, suggesting its importance for skeletal muscle development and muscle function. We revealed here that KLF4 plays a critical role in skeletal muscle development and regeneration. Specific knockout of KLF4 in skeletal muscle impaired muscle formation further affecting physical activity and also defected skeletal muscle regeneration. In vitro, KLF4 was highly expressed in proliferating myoblasts and early differentiated cells. KLF4 knockdown promoted myoblast proliferation and inhibited myoblast fusion, while its overexpression showed opposite results. Mechanically, in proliferating myoblasts, KLF4 inhibits myoblast proliferation through regulating cell cycle arrest protein P57 by directly targeting its promoter; while in differentiated myoblasts, KLF4 promotes myoblast fusion by transcriptionally activating Myomixer. Our study provides mechanistic information for skeletal muscle development, reduced muscle strength and impaired regeneration after injury and unveiling the mechanism of KLF4 in myogenic regulation.
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Affiliation(s)
- Shufang Cai
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Xiaoyu Wang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Rong Xu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Ziyun Liang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Qi Zhu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Meilin Chen
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Zhuhu Lin
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Chenggan Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Tianqi Duo
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Xian Tong
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Enru Li
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Zuyong He
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Xiaohong Liu
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Yaosheng Chen
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China
| | - Delin Mo
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong, China.
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3
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Elzinga J, van der Lugt B, Belzer C, Steegenga WT. Characterization of increased mucus production of HT29-MTX-E12 cells grown under Semi-Wet interface with Mechanical Stimulation. PLoS One 2021; 16:e0261191. [PMID: 34928974 PMCID: PMC8687553 DOI: 10.1371/journal.pone.0261191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 11/24/2021] [Indexed: 12/29/2022] Open
Abstract
The intestinal mucus layer plays a crucial role in human health. To study intestinal mucus function and structure in vitro, the mucus-producing intestinal cell line HT29-MTX-E12 has been commonly used. However, this cell line produces only low amounts of the intestine-specific MUC2. It has been shown previously that HT29-MTX-E12 cells cultured under Semi-Wet interface with Mechanical Stimulation (SWMS) produced higher amounts of MUC2, concomitant with a thicker mucus layer, compared to cells cultured conventionally. However, it remains unknown which underlying pathways are involved. Therefore, we aimed to further explore the cellular processes underlying the increased MUC2 production by HT29-MTX-E12 cells grown under SWMS conditions. Cells grown on Transwell membranes for 14 days under static and SWMS conditions (after cell seeding and attachment) were subjected to transcriptome analysis to investigate underlying molecular pathways at gene expression level. Caco-2 and LS174T cell lines were included as references. We characterized how SWMS conditions affected HT29-MTX-E12 cells in terms of epithelial barrier integrity, by measuring transepithelial electrical resistance, and cell metabolism, by monitoring pH and lactate production per molecule glucose of the conditioned medium. We confirmed higher MUC2 production under SWMS conditions at gene and protein level and demonstrated that this culturing method primarily stimulated cell growth. In addition, we also found evidence for a more aerobic cell metabolism under SWMS, as shown previously for similar models. In summary, we suggest different mechanisms by which MUC2 production is enhanced under SWMS and propose potential applications of this model in future studies.
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Affiliation(s)
- Janneke Elzinga
- Laboratory of Microbiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Benthe van der Lugt
- Division of Human Nutrition and Health, Wageningen University and Research, Wageningen, The Netherlands
| | - Clara Belzer
- Laboratory of Microbiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Wilma T Steegenga
- Division of Human Nutrition and Health, Wageningen University and Research, Wageningen, The Netherlands
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4
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Tong L, Tang C, Cai C, Guan X. Upregulation of the microRNA rno-miR-146b-5p may be involved in the development of intestinal injury through inhibition of Kruppel-like factor 4 in intestinal sepsis. Bioengineered 2020; 11:1334-1349. [PMID: 33200654 PMCID: PMC8291882 DOI: 10.1080/21655979.2020.1851476] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Regulatory mechanisms of microRNAs (miRNAs) in the development of intestinal sepsis are unclear. This study investigated the role of rno-miR-146b-5p in sepsis-induced intestinal injury. A rat sepsis model was created using the cecal ligation and puncture method. The expression profiles of miRNA and mRNA in sepsis rats were examined using miRNA and mRNA sequencing; rno-miR-146b was selected for further investigation. The mimics and inhibitors of rno-miR-146b-5p were transfected into IEC-6 cells and then with or without lipopolysaccharide (LPS) treatment, and the expressions of Kruppel-like factor 4 (Klf4) and Cyclin D2 (Ccnd2) were assessed by quantitative real-time transcriptase-polymerase chain reaction (qRT-PCR) and western blotting. Next, cell counting kit-8 assay was used to detect cell viability, and scratch wound healing assay was used to assess cell migration. In sepsis rat model, crypt cell proliferation was inhibited and crypt cell apoptosis was increased. Compared with the sham control, results of miRNA and mRNA sequencing showed that there were 17 miRNAs and 1617 mRNAs that were upregulated and 123 miRNAs and 1917 mRNAs that were downregulated in the sepsis model group. The network diagrams and qRT-PCR validation indicated that rno-miR-146b-5p may inhibit the expression of Klf4. By adjusting the expression of rno-miR-146b-5p in IEC-6 cells with or without LPS treatment, we found that increased expression of rno-miR-146b-5p inhibited cell proliferation and migration and inhibited the expression of Ccnd2. rno-miR-146b-5p may play a vital role in the development of sepsis intestinal injury through targeting Klf4 expression and affecting promoter activity of Ccnd2.
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Affiliation(s)
- Li Tong
- Department of Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Chaoxia Tang
- Department of Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Changjie Cai
- Department of Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Xiangdong Guan
- Department of Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
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5
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Recent Discoveries on the Involvement of Krüppel-Like Factor 4 in the Most Common Cancer Types. Int J Mol Sci 2020; 21:ijms21228843. [PMID: 33266506 PMCID: PMC7700188 DOI: 10.3390/ijms21228843] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/20/2020] [Accepted: 11/21/2020] [Indexed: 02/06/2023] Open
Abstract
Krüppel-like factor 4 (KLF4) is a transcription factor highly conserved in evolution. It is particularly well known for its role in inducing pluripotent stem cells. In addition, KLF4 plays many roles in cancer. The results of most studies suggest that KLF4 is a tumor suppressor. However, the functioning of KLF4 is regulated at many levels. These include regulation of transcription, alternative splicing, miRNA, post-translational modifications, subcellular localization, protein stability and interactions with other molecules. Simple experiments aimed at assaying transcript levels or protein levels fail to address this complexity and thus may deliver misleading results. Tumor subtypes are also important; for example, in prostate cancer KLF4 is highly expressed in indolent tumors where it impedes tumor progression, while it is absent from aggressive prostate tumors. KLF4 is important in regulating response to many known drugs, and it also plays a role in tumor microenvironment. More and more information is available about upstream regulators, downstream targets and signaling pathways associated with the involvement of KLF4 in cancer. Furthermore, KLF4 performs critical function in the overall regulation of tissue homeostasis, cellular integrity, and progression towards malignancy. Here we summarize and analyze the latest findings concerning this fascinating transcription factor.
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Bradley T, Kuraoka M, Yeh CH, Tian M, Chen H, Cain DW, Chen X, Cheng C, Ellebedy AH, Parks R, Barr M, Sutherland LL, Scearce RM, Bowman CM, Bouton-Verville H, Santra S, Wiehe K, Lewis MG, Ogbe A, Borrow P, Montefiori D, Bonsignori M, Anthony Moody M, Verkoczy L, Saunders KO, Ahmed R, Mascola JR, Kelsoe G, Alt FW, Haynes BF. Immune checkpoint modulation enhances HIV-1 antibody induction. Nat Commun 2020; 11:948. [PMID: 32075963 PMCID: PMC7031230 DOI: 10.1038/s41467-020-14670-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 01/27/2020] [Indexed: 12/19/2022] Open
Abstract
Eliciting protective titers of HIV-1 broadly neutralizing antibodies (bnAbs) is a goal of HIV-1 vaccine development, but current vaccine strategies have yet to induce bnAbs in humans. Many bnAbs isolated from HIV-1-infected individuals are encoded by immunoglobulin gene rearrangments with infrequent naive B cell precursors and with unusual genetic features that may be subject to host regulatory control. Here, we administer antibodies targeting immune cell regulatory receptors CTLA-4, PD-1 or OX40 along with HIV envelope (Env) vaccines to rhesus macaques and bnAb immunoglobulin knock-in (KI) mice expressing diverse precursors of CD4 binding site HIV-1 bnAbs. CTLA-4 blockade augments HIV-1 Env antibody responses in macaques, and in a bnAb-precursor mouse model, CTLA-4 blocking or OX40 agonist antibodies increase germinal center B and T follicular helper cells and plasma neutralizing antibodies. Thus, modulation of CTLA-4 or OX40 immune checkpoints during vaccination can promote germinal center activity and enhance HIV-1 Env antibody responses. Elucidation of broadly neutralizing antibodies (bnAb) is a goal in HIV vaccine development. Here, Bradley et al. show that administration of CTLA-4 blocking antibody with vaccine antigens increases HIV-1 envelope antibody responses in macaques and a bnAb precursor mouse model.
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Affiliation(s)
- Todd Bradley
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA. .,Department of Medicine, Duke University School of Medicine, Durham, NC, 27710, USA. .,Center for Pediatric Genomic Medicine, Children's Mercy Kansas City, Kansas City, MO, 64108, USA. .,Department of Pediatrics, UMKC School of Medicine, Kansas City, MO, 64108, USA.
| | - Masayuki Kuraoka
- Department of Immunology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Chen-Hao Yeh
- Department of Immunology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Ming Tian
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetic, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, 02115, USA
| | - Huan Chen
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetic, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, 02115, USA
| | - Derek W Cain
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Medicine, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Xuejun Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Cheng Cheng
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Ali H Ellebedy
- Emory Vaccine Center, Emory University, Atlanta, GA, 30317, USA.,Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, 63110, USA
| | - Robert Parks
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Maggie Barr
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Laura L Sutherland
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Richard M Scearce
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Cindy M Bowman
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Hilary Bouton-Verville
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Sampa Santra
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02115, USA
| | - Kevin Wiehe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Medicine, Duke University School of Medicine, Durham, NC, 27710, USA
| | | | - Ane Ogbe
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7FZ, UK
| | - Persephone Borrow
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7FZ, UK
| | - David Montefiori
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Surgery, Duke University, Durham, NC, 27710, USA
| | - Mattia Bonsignori
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Medicine, Duke University School of Medicine, Durham, NC, 27710, USA
| | - M Anthony Moody
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Immunology, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Pediatrics, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Laurent Verkoczy
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,San Diego Biomedical Research Institute, San Diego, CA, 92121, USA
| | - Kevin O Saunders
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Surgery, Duke University, Durham, NC, 27710, USA
| | - Rafi Ahmed
- Emory Vaccine Center, Emory University, Atlanta, GA, 30317, USA
| | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Garnett Kelsoe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.,Department of Immunology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Frederick W Alt
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Department of Genetic, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, 02115, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA. .,Department of Medicine, Duke University School of Medicine, Durham, NC, 27710, USA. .,Department of Immunology, Duke University School of Medicine, Durham, NC, 27710, USA.
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7
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Chen YC, Liao BK, Lu YF, Liu YH, Hsieh FC, Hwang PP, Hwang SPL. Zebrafish Klf4 maintains the ionocyte progenitor population by regulating epidermal stem cell proliferation and lateral inhibition. PLoS Genet 2019; 15:e1008058. [PMID: 30933982 PMCID: PMC6459544 DOI: 10.1371/journal.pgen.1008058] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 04/11/2019] [Accepted: 02/28/2019] [Indexed: 01/06/2023] Open
Abstract
In the skin and gill epidermis of fish, ionocytes develop alongside keratinocytes and maintain body fluid ionic homeostasis that is essential for adaptation to environmental fluctuations. It is known that ionocyte progenitors in zebrafish embryos are specified from p63+ epidermal stem cells through a patterning process involving DeltaC (Dlc)-Notch-mediated lateral inhibition, which selects scattered dlc+ cells into the ionocyte progenitor fate. However, mechanisms by which the ionocyte progenitor population is modulated remain unclear. Krüppel-like factor 4 (Klf4) transcription factor was previously implicated in the terminal differentiation of mammalian skin epidermis and is known for its bifunctional regulation of cell proliferation in a tissue context-dependent manner. Here, we report novel roles for zebrafish Klf4 in the ventral ectoderm during embryonic skin development. We found that Klf4 was expressed in p63+ epidermal stem cells of the ventral ectoderm from 90% epiboly onward. Knockdown or knockout of klf4 expression reduced the proliferation rate of p63+ stem cells, resulting in decreased numbers of p63+ stem cells, dlc-p63+ keratinocyte progenitors and dlc+ p63+ ionocyte progenitor cells. These reductions subsequently led to diminished keratinocyte and ionocyte densities and resulted from upregulation of the well-known cell cycle regulators, p53 and cdkn1a/p21. Moreover, mutation analyses of the KLF motif in the dlc promoter, combined with VP16-klf4 or engrailed-klf4 mRNA overexpression analyses, showed that Klf4 can bind the dlc promoter and modulate lateral inhibition by directly repressing dlc expression. This idea was further supported by observing the lateral inhibition outcomes in klf4-overexpressing or knockdown embryos. Overall, our experiments delineate novel roles for zebrafish Klf4 in regulating the ionocyte progenitor population throughout early stem cell stage to initiation of terminal differentiation, which is dependent on Dlc-Notch-mediated lateral inhibition.
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Affiliation(s)
- Yi-Chung Chen
- Institute of Cellular and Organismic Biology (ICOB), Academia Sinica, Taipei, Taiwan, Republic of China
| | - Bo-Kai Liao
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan, Republic of China
| | - Yu-Fen Lu
- Institute of Cellular and Organismic Biology (ICOB), Academia Sinica, Taipei, Taiwan, Republic of China
| | - Yu-Hsiu Liu
- Institute of Cellular and Organismic Biology (ICOB), Academia Sinica, Taipei, Taiwan, Republic of China
- Department of Life Science, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Fang-Chi Hsieh
- Institute of Cellular and Organismic Biology (ICOB), Academia Sinica, Taipei, Taiwan, Republic of China
- Graduate Institute of Life Sciences, National Defense Medical Center, Taiwan, Republic of China
| | - Pung-Pung Hwang
- Institute of Cellular and Organismic Biology (ICOB), Academia Sinica, Taipei, Taiwan, Republic of China
| | - Sheng-Ping L. Hwang
- Institute of Cellular and Organismic Biology (ICOB), Academia Sinica, Taipei, Taiwan, Republic of China
- Department of Life Science, National Taiwan University, Taipei, Taiwan, Republic of China
- Graduate Institute of Life Sciences, National Defense Medical Center, Taiwan, Republic of China
- * E-mail:
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8
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Chokeshaiusaha K, Sananmuang T, Puthier D, Nguyen C. An innovative approach to predict immune-associated genes mutually targeted by cow and human milk microRNAs expression profiles. Vet World 2018; 11:1203-1209. [PMID: 30410222 PMCID: PMC6200572 DOI: 10.14202/vetworld.2018.1203-1209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 07/16/2018] [Indexed: 12/21/2022] Open
Abstract
Aim: Milk is rich in miRNAs - the endogenous small non-coding RNA responsible for gene post-transcriptional silencing. Milk miRNAs were previously evidenced to affect consumer’s immune response. While most studies relied on a few well-characterized milk miRNAs to relate their immunoregulatory roles on target genes among mammals, this study introduced a procedure to predict the target genes based on overall milk miRNA expression profiles - the miRNome data of cow and human. Materials and Methods: Cow and human milk miRNome expression datasets of cow and human milk lipids at 2, 4, and 6 months of lactation periods were preprocessed and predicted for their target genes using TargetScanHuman. Enrichment analysis was performed using target genes to extract the immune-associated gene ontology (GO) terms shared between the two species. The genes within these terms with more than 50 different miRNAs of each species targeting were selected and reviewed for their immunological functions. Results: A total of 146 and 129 miRNAs were identified in cow and human milk with several miRNAs reproduced from other previous reports. Enrichment analysis revealed nine immune-related GO terms shared between cow and human (adjusted p≤0.01). There were 14 genes related to these terms with more than 50 miRNA genes of each species targeting them. These genes were evidenced for their major roles in lymphocyte stimulation and differentiation. Conclusion: A novel procedure to determine mutual immune-associated genes targeted by milk miRNAs was demonstrated using cow and human milk miRNome data. As far as we know, this was the 1st time that milk miRNA target genes had been identified based on such cross-species approach. Hopefully, the introduced strategy should hereby facilitate a variety of cross-species miRNA studies in the future.
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Affiliation(s)
- Kaj Chokeshaiusaha
- Department of Veterinary Science, Faculty of Veterinary Medicine, Rajamangala University of Technology Tawan-OK, Chonburi, Thailand
| | - Thanida Sananmuang
- Department of Veterinary Science, Faculty of Veterinary Medicine, Rajamangala University of Technology Tawan-OK, Chonburi, Thailand
| | - Denis Puthier
- Aix-Marseille Université, INSERM UMR 1090, TAGC, Marseille, France
| | - Catherine Nguyen
- Aix-Marseille Université, INSERM UMR 1090, TAGC, Marseille, France
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9
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Sweet DR, Fan L, Hsieh PN, Jain MK. Krüppel-Like Factors in Vascular Inflammation: Mechanistic Insights and Therapeutic Potential. Front Cardiovasc Med 2018; 5:6. [PMID: 29459900 PMCID: PMC5807683 DOI: 10.3389/fcvm.2018.00006] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/17/2018] [Indexed: 12/19/2022] Open
Abstract
The role of inflammation in vascular disease is well recognized, involving dysregulation of both circulating immune cells as well as the cells of the vessel wall itself. Unrestrained vascular inflammation leads to pathological remodeling that eventually contributes to atherothrombotic disease and its associated sequelae (e.g., myocardial/cerebral infarction, embolism, and critical limb ischemia). Signaling events during vascular inflammation orchestrate widespread transcriptional programs that affect the functions of vascular and circulating inflammatory cells. The Krüppel-like factors (KLFs) are a family of transcription factors central in regulating vascular biology in states of homeostasis and disease. Given their abundance and diversity of function in cells associated with vascular inflammation, understanding the transcriptional networks regulated by KLFs will further our understanding of the pathogenesis underlying several pervasive health concerns (e.g., atherosclerosis, stroke, etc.) and consequently inform the treatment of cardiovascular disease. Within this review, we will discuss the role of KLFs in coordinating protective and deleterious responses during vascular inflammation, while addressing the potential targeting of these critical transcription factors in future therapies.
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Affiliation(s)
- David R Sweet
- Case Cardiovascular Research Institute, Case Western Reserve University, Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Department of Pathology, Case Western Reserve University, Cleveland, OH, United States
| | - Liyan Fan
- Case Cardiovascular Research Institute, Case Western Reserve University, Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Department of Pathology, Case Western Reserve University, Cleveland, OH, United States
| | - Paishiun N Hsieh
- Case Cardiovascular Research Institute, Case Western Reserve University, Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, United States.,Department of Pathology, Case Western Reserve University, Cleveland, OH, United States
| | - Mukesh K Jain
- Case Cardiovascular Research Institute, Case Western Reserve University, Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
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10
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Analysis of region specific gene expression patterns in the heart and systemic responses after experimental myocardial ischemia. Oncotarget 2017; 8:60809-60825. [PMID: 28977827 PMCID: PMC5617387 DOI: 10.18632/oncotarget.17955] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/03/2017] [Indexed: 12/21/2022] Open
Abstract
Aims Ischemic myocardial injury leads to the activation of inflammatory mechanisms and results in ventricular remodeling. Although great efforts have been made to unravel the molecular and cellular processes taking place in the ischemic myocardium, little is known about the effects on the surrounding tissue and other organs. The aim of this study was to determine region specific differences in the myocardium and in distant organs after experimental myocardial infarction by using a bioinformatics approach. Methods and Results A porcine closed chest reperfused acute myocardial infarction model and mRNA microarrays have been used to evaluate gene expression changes. Myocardial infarction changed the expression of 8903 genes in myocardial-, 856 in hepatic- and 338 in splenic tissue. Identification of myocardial region specific differences as well as expression profiling of distant organs revealed clear gene-regulation patterns within the first 24 hours after ischemia. Transcription factor binding site analysis suggested a strong role for Kruppel like factor 4 (Klf4) in the regulation of gene expression following myocardial infarction, and was therefore investigated further by immunohistochemistry. Strong nuclear Klf4 expression with clear region specific differences was detectable in porcine and human heart samples after myocardial infarction. Conclusion Apart from presenting a post myocardial infarction gene expression database and specific response pathways, the key message of this work is that myocardial ischemia does not end at the injured myocardium. The present results have enlarged the spectrum of organs affected, and suggest that a variety of organ systems are involved in the co-ordination of the organism´s response to myocardial infarction.
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11
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Ghaleb AM, Yang VW. Krüppel-like factor 4 (KLF4): What we currently know. Gene 2017; 611:27-37. [PMID: 28237823 DOI: 10.1016/j.gene.2017.02.025] [Citation(s) in RCA: 352] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 02/17/2017] [Accepted: 02/21/2017] [Indexed: 02/06/2023]
Abstract
Krüppel-like factor 4 (KLF4) is an evolutionarily conserved zinc finger-containing transcription factor that regulates diverse cellular processes such as cell growth, proliferation, and differentiation. Since its discovery in 1996, KLF4 has been gaining a lot of attention, particularly after it was shown in 2006 as one of four factors involved in the induction of pluripotent stem cells (iPSCs). Here we review the current knowledge about the different functions and roles of KLF4 in various tissue and organ systems.
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Affiliation(s)
- Amr M Ghaleb
- Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA
| | - Vincent W Yang
- Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, USA.
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12
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Jang SH, Chen H, Gregersen PK, Diamond B, Kim SJ. Kruppel-like factor4 regulates PRDM1 expression through binding to an autoimmune risk allele. JCI Insight 2017; 2:e89569. [PMID: 28097234 DOI: 10.1172/jci.insight.89569] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A SNP identified as rs548234, which is found in PRDM1, the gene that encodes BLIMP1, is a risk allele associated with systemic lupus erythematosus (SLE). BLIMP1 expression was reported to be decreased in women with the PRDM1 rs548234 risk allele compared with women with the nonrisk allele in monocyte-derived DCs (MO-DCs). In this study, we demonstrate that BLIMP1 expression is regulated by the binding of Kruppel-like factor 4 (KLF4) to the risk SNP. KLF4 is highly expressed in MO-DCs but undetectable in B cells, consistent with the lack of altered expression of BLIMP1 in B cells from risk SNP carriers. Female rs548234 risk allele carriers, but not nonrisk allele carriers, exhibited decreased levels of BLIMP1 in MO-DCs, showing that the regulatory function of KLF4 is influenced by the risk allele. In addition, KLF4 directly recruits histone deacetylases (HDAC4, HDAC6, and HDAC7), established negative regulators of gene expression. Finally, the knock down of KLF4 expression reversed the inhibitory effects of the risk SNP on promoter activity and BLIMP1 expression. Therefore, the binding of KLF4 and the subsequent recruitment of HDACs represent a mechanism for reduced BLIMP1 expression in MO-DCs bearing the SLE risk allele rs548234.
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Affiliation(s)
- Su Hwa Jang
- Center for Autoimmune and Musculoskeletal Diseases and
| | - Helen Chen
- Center for Autoimmune and Musculoskeletal Diseases and
| | - Peter K Gregersen
- Center for Genomics and Human Genetics, The Feinstein Institute for Medical Research, Manhasset, New York, New York, USA
| | - Betty Diamond
- Center for Autoimmune and Musculoskeletal Diseases and
| | - Sun Jung Kim
- Center for Autoimmune and Musculoskeletal Diseases and
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13
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Siu MK, Suau F, Chen WY, Tsai YC, Tsai HY, Yeh HL, Liu YN. KLF4 functions as an activator of the androgen receptor through reciprocal feedback. Oncogenesis 2016; 5:e282. [PMID: 27991915 PMCID: PMC5177777 DOI: 10.1038/oncsis.2016.79] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 10/07/2016] [Accepted: 11/02/2016] [Indexed: 12/17/2022] Open
Abstract
In prostate cancer, Krüppel-like factor 4 (KLF4) depletion occurs frequently, suggesting a role as suppressor tumor. KLF4 is a transcription factor associated with androgen receptor (AR) expression; however, its cellular functions and signaling regulation mechanism remain largely unknown. In this study, we demonstrated that activated AR binds to the KLF4 promoter and enhances KLF4 expression, which reciprocally targets the AR promoter, thus sustaining KLF4 activity. Ectopic KLF4 expression in androgen-independent prostate cancer cells induced AR expression and decreased cell proliferation, invasion and bone metastasis. We previously showed that increased microRNA (miR)-1 expression is associated with reduced bone metastasis of prostate cancer cells. Here we observed that KLF4 targets the primary miR-1-2 stem-loop promoter and stimulates miR-1 expression. In clinical prostate cancer specimens, KLF4 levels were positively correlated with miR-1 and AR levels. These data suggest that the loss of KLF4 expression is one mechanistic link between aggressive prostate cancer progression and low canonical AR output through miR-1 inactivation.
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Affiliation(s)
- M-K Siu
- Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei, Taiwan.,Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.,Department of Anesthesiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - F Suau
- Department of Microbiology, Faculty of Pharmacy, Dicle University, Diyarbakir, Turkey
| | - W-Y Chen
- Department of Pathology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Pathology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Y-C Tsai
- Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei, Taiwan.,Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - H-Y Tsai
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - H-L Yeh
- Institute of Information System and Applications, National Tsing Hua University, Hsinchu, Taiwan
| | - Y-N Liu
- Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei, Taiwan.,Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
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14
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Eyking A, Reis H, Frank M, Gerken G, Schmid KW, Cario E. MiR-205 and MiR-373 Are Associated with Aggressive Human Mucinous Colorectal Cancer. PLoS One 2016; 11:e0156871. [PMID: 27271572 PMCID: PMC4894642 DOI: 10.1371/journal.pone.0156871] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 05/20/2016] [Indexed: 02/07/2023] Open
Abstract
Mucinous adenocarcinoma (MAC) represents a distinct histopathological entity of colorectal cancer (CRC), which is associated with disease progression and poor prognosis. Here, we found that expression levels of miR-205 and miR-373 were specifically upregulated only in patients with mucinous colon cancers, but not in CRC that lack mucinous components. To investigate the effects of miR-205 and miR-373 on intestinal epithelial cell (IEC) biology by gain- and loss-of-function experiments in a proof-of-concept approach, we chose previously established in-vitro human Caco-2-based models of differentiated, non-invasive (expressing TLR4 wild-type; termed Caco-2[WT]) versus undifferentiated, invasive (expressing TLR4 mutant D299G; termed Caco-2[D299G]) IEC. Enterocyte-like Caco-2[WT] showed low levels of miR-205 and miR-373 expression, while both miRNAs were significantly upregulated in colorectal carcinoma-like Caco-2[D299G], thus resembling the miRNA expression pattern of paired normal versus tumor samples from MAC patients. Using stable transfection, we generated miR-205- or miR-373-expressing and miR-205- or miR-373-inhibiting subclones of these IEC lines. We found that introduction of miR-205 into Caco-2[WT] led to expansion of mucus-secreting goblet cell-like cells, which was associated with induction of KLF4, MUC2 and TGFβ1 expression. Activation of miR-205 in Caco-2[WT] induced chemoresistance, while inhibition of miR-205 in Caco-2[D299G] promoted chemosensitivity. Caco-2[WT] overexpressing miR-373 showed mitotic abnormalities and underwent morphologic changes (loss of epithelial polarity, cytoskeletal reorganization, and junctional disruption) associated with epithelial-mesenchymal transition and progression to inflammation-associated colonic carcinoma, which correlated with induction of phosphorylated STAT3 and N-CADHERIN expression. Functionally, introduction of miR-373 into Caco-2[WT] mediated loss of cell-cell adhesion and increased proliferation and invasion. Reversely, inhibition of miR-373 allowed mesenchymal IEC to regain epithelial properties, which correlated with absence of neoplastic progression. Using xenografts in mice demonstrated miR-373-mediated acceleration of malignant intestinal tumor growth. In conclusion, our results provide first evidence that miR-205 and miR-373 may differentially contribute to the aggressive phenotype of MAC in CRC.
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Affiliation(s)
- Annette Eyking
- Department of Gastroenterology and Hepatology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Henning Reis
- Institute of Pathology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Magdalena Frank
- Department of Gastroenterology and Hepatology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Guido Gerken
- Department of Gastroenterology and Hepatology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Kurt W. Schmid
- Institute of Pathology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Elke Cario
- Department of Gastroenterology and Hepatology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- * E-mail:
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15
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Schoenhals M, Jourdan M, Seckinger A, Pantesco V, Hose D, Kassambara A, Moreaux J, Klein B. Forced KLF4 expression increases the generation of mature plasma cells and uncovers a network linked with plasma cell stage. Cell Cycle 2016; 15:1919-28. [PMID: 27230497 DOI: 10.1080/15384101.2016.1191709] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A role of the transcription factor Krüppel-like factor 4 (KLF4) in the generation of mature plasma cells (PC) is unknown. Indeed, KLF4 is critical in controlling the differentiation of various cell linages, particularly monocytes and epithelial cells. KLF4 is expressed at low levels in pro-B cells and its expression increases as they mature into pre-B cells, resting naïve B cells and memory B cells. We show here that KLF4 is expressed in human bone marrow plasma cells and its function was studied using an in vitro model of differentiation of memory B cells into long lived plasma cells. KLF4 is rapidly lost when memory B cells differentiate into highly cell cycling plasmablasts, poorly cycling early plasma cells and then quiescent long-lived plasma cells. A forced expression of KLF4 in plasmablasts enhances the yield of their differentiation into early plasma cell and long lived plasma cells, by inhibiting apoptosis and upregulating previously unknown plasma cell pathways.
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Affiliation(s)
- Matthieu Schoenhals
- a Department of Biological Hematology , CHU Montpellier , Montpellier , France
| | - Michel Jourdan
- b Institute of Human Genetics, CNRS-UPR1142 , Montpellier , France
| | - Anja Seckinger
- c Medizinische Klinik und Poliklinik V, Universitätsklinikum Heidelberg , Heidelberg , Germany.,d Nationales Centrum für Tumorerkrankungen , Heidelberg , Germany
| | | | - Dirk Hose
- c Medizinische Klinik und Poliklinik V, Universitätsklinikum Heidelberg , Heidelberg , Germany.,d Nationales Centrum für Tumorerkrankungen , Heidelberg , Germany
| | | | - Jérôme Moreaux
- a Department of Biological Hematology , CHU Montpellier , Montpellier , France.,b Institute of Human Genetics, CNRS-UPR1142 , Montpellier , France.,f University of Montpellier 1, UFR de Médecine , Montpellier , France
| | - Bernard Klein
- a Department of Biological Hematology , CHU Montpellier , Montpellier , France.,b Institute of Human Genetics, CNRS-UPR1142 , Montpellier , France.,f University of Montpellier 1, UFR de Médecine , Montpellier , France
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16
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Riz I, Hawley TS, Hawley RG. KLF4-SQSTM1/p62-associated prosurvival autophagy contributes to carfilzomib resistance in multiple myeloma models. Oncotarget 2016; 6:14814-31. [PMID: 26109433 PMCID: PMC4558117 DOI: 10.18632/oncotarget.4530] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 05/22/2015] [Indexed: 11/25/2022] Open
Abstract
Multiple myeloma (MM) is an incurable clonal plasma cell malignancy. Because of a high rate of immunoglobulin synthesis, the endoplasmic reticulum of MM cells is subjected to elevated basal levels of stress. Consequently, proteasome inhibitors, which exacerbate this stress by inhibiting ubiquitin-proteasome-mediated protein degradation, are an important new class of chemotherapeutic agents being used to combat this disease. However, MM cells still develop resistance to proteasome inhibitors such as carfilzomib. Toward this end, we have established carfilzomib-resistant derivatives of MM cell lines. We found that resistance to carfilzomib was associated with elevated levels of prosurvival autophagy, and Kruppel-like factor 4 (KLF4) was identified as a contributing factor. Expression levels as well as nuclear localization of KLF4 protein were elevated in MM cells with acquired carfilzomib resistance. Chromatin immunoprecipitations indicated that endogenous KLF4 bound to the promoter regions of the SQSTM1 gene encoding the ubiquitin-binding adaptor protein sequestosome/p62 that links the proteasomal and autophagic protein degradation pathways. Ectopic expression of KLF4 induced upregulation of SQSTM1. On the other hand, inhibitors of autophagy sensitized MM cells to carfilzomib, even in carfilzomib-resistant derivatives having increased expression of the multidrug resistance protein P-glycoprotein. Thus, we report here a novel function for KLF4, one of the Yamanaka reprogramming factors, as being a contributor to autophagy gene expression which moderates preclinical proteasome inhibitor efficacy in MM.
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Affiliation(s)
- Irene Riz
- Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC, USA
| | - Teresa S Hawley
- Flow Cytometry Core Facility, The George Washington University, Washington, DC, USA
| | - Robert G Hawley
- Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC, USA
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17
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Filarsky K, Garding A, Becker N, Wolf C, Zucknick M, Claus R, Weichenhan D, Plass C, Döhner H, Stilgenbauer S, Lichter P, Mertens D. Krüppel-like factor 4 (KLF4) inactivation in chronic lymphocytic leukemia correlates with promoter DNA-methylation and can be reversed by inhibition of NOTCH signaling. Haematologica 2016; 101:e249-53. [PMID: 27081174 DOI: 10.3324/haematol.2015.138172] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Affiliation(s)
- Katharina Filarsky
- Mechanisms of Leukemogenesis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Angela Garding
- Signaling to Chromatin Laboratory, Institute of Molecular Biology, Mainz, Germany
| | - Natalia Becker
- Division of Biostatistics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Christine Wolf
- Mechanisms of Leukemogenesis, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Manuela Zucknick
- Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Norway
| | - Rainer Claus
- Division of Hematology, University of Freiburg Medical Center, Germany
| | - Dieter Weichenhan
- Division of Epigenetics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Christoph Plass
- Division of Epigenetics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Hartmut Döhner
- Department of Internal Medicine III, University of Ulm, Germany
| | | | - Peter Lichter
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Daniel Mertens
- Mechanisms of Leukemogenesis, German Cancer Research Center (DKFZ), Heidelberg, Germany Department of Internal Medicine III, University of Ulm, Germany
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18
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Park CS, Shen Y, Lewis A, Lacorazza HD. Role of the reprogramming factor KLF4 in blood formation. J Leukoc Biol 2016; 99:673-85. [DOI: 10.1189/jlb.1ru1215-539r] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 01/22/2016] [Indexed: 12/31/2022] Open
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19
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Tartey S, Matsushita K, Imamura T, Wakabayashi A, Ori D, Mino T, Takeuchi O. Essential Function for the Nuclear Protein Akirin2 in B Cell Activation and Humoral Immune Responses. THE JOURNAL OF IMMUNOLOGY 2015; 195:519-27. [DOI: 10.4049/jimmunol.1500373] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 05/07/2015] [Indexed: 02/06/2023]
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20
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Role of miRNA let-7 and its major targets in prostate cancer. BIOMED RESEARCH INTERNATIONAL 2014; 2014:376326. [PMID: 25276782 PMCID: PMC4168040 DOI: 10.1155/2014/376326] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 08/11/2014] [Accepted: 08/18/2014] [Indexed: 12/21/2022]
Abstract
Prostate cancer is worldwide the sixth leading cause of cancer related death in men thus early detection and successful treatment are still of major interest. The commonly performed screening of the prostate-specific antigen (PSA) is controversially discussed, as in many patients the prostate-specific antigen levels are chronically elevated in the absence of cancer. Due to the unsatisfying efficiency of available prostate cancer screening markers and the current treatment outcome of the aggressive hormone refractory prostate cancer, the evaluation of novel molecular markers and targets is considered an issue of high importance. MicroRNAs are relatively stable in body fluids orchestrating simultaneously the expression of many genes. These molecules are currently discussed to bear a greater diagnostic potential than protein-coding genes, being additionally promising therapeutic drugs and/or targets. Herein we review the potential impact of the microRNA let-7 family on prostate cancer and show how deregulation of several of its target genes could influence the cellular equilibrium in the prostate gland, promoting cancer development as they do in a variety of other human malignant neoplasias.
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21
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Hale AT, Tian H, Anih E, Recio FO, Shatat MA, Johnson T, Liao X, Ramirez-Bergeron DL, Proweller A, Ishikawa M, Hamik A. Endothelial Kruppel-like factor 4 regulates angiogenesis and the Notch signaling pathway. J Biol Chem 2014; 289:12016-12028. [PMID: 24599951 PMCID: PMC4002108 DOI: 10.1074/jbc.m113.530956] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 02/18/2014] [Indexed: 01/08/2023] Open
Abstract
Regulation of endothelial cell biology by the Notch signaling pathway (Notch) is essential to vascular development, homeostasis, and sprouting angiogenesis. Although Notch determines cell fate and differentiation in a wide variety of cells, the molecular basis of upstream regulation of Notch remains poorly understood. Our group and others have implicated the Krüppel-like factor family of transcription factors as critical regulators of endothelial function. Here, we show that Krüppel-like factor 4 (KLF4) is a central regulator of sprouting angiogenesis via regulating Notch. Using a murine model in which KLF4 is overexpressed exclusively in the endothelium, we found that sustained expression of KLF4 promotes ineffective angiogenesis leading to diminished tumor growth independent of endothelial cell proliferation or cell cycling effects. These tumors feature increased vessel density yet are hypoperfused, leading to tumor hypoxia. Mechanistically, we show that KLF4 differentially regulates expression of Notch receptors, ligands, and target genes. We also demonstrate that KLF4 limits cleavage-mediated activation of Notch1. Finally, we rescue Notch target gene expression and the KLF4 sprouting angiogenesis phenotype by supplementation of DLL4 recombinant protein. Identification of this hitherto undiscovered role of KLF4 implicates this transcription factor as a critical regulator of Notch, tumor angiogenesis, and sprouting angiogenesis.
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Affiliation(s)
- Andrew T Hale
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Hongmei Tian
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Ejike Anih
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Fernando O Recio
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Mohammad A Shatat
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Division of Pulmonary, Critical Care and Sleep Medicine
| | - Trent Johnson
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Xudong Liao
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Diana L Ramirez-Bergeron
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Aaron Proweller
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Masakazu Ishikawa
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106
| | - Anne Hamik
- Case Cardiovascular Research Institute and Harrington Heart & Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, Ohio 44106; Division of Cardiovascular Medicine, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio 44106.
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22
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Ma Y, Shi Y, Li W, Sun A, Zang P, Zhang P. Epigallocatechin-3-gallate regulates the expression of Kruppel-like factor 4 through myocyte enhancer factor 2A. Cell Stress Chaperones 2014; 19:217-26. [PMID: 23884787 PMCID: PMC3933619 DOI: 10.1007/s12192-013-0447-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Revised: 07/04/2013] [Accepted: 07/10/2013] [Indexed: 12/13/2022] Open
Abstract
Epigallocatechin-3-gallate (EGCG), a powerful antioxidant and free ion scavenger found in green tea, exhibits inhibitory effects on different stages of tumorigenesis. Within gastric cancer cells, the transcription factor Kruppel-like factor 4 (KLF4) is downregulated, and it is possible that EGCG exerts its anti-tumorigenic function through modulation of KLF4 expression. In order to examine the effects of EGCG on KLF4 in a gastric tumor model, we treated the gastric cancer cell line NCI-N87 with EGCG. We found that EGCG treatment results in increased expression of KLF4 and alters expression of the KLF4 target genes p21, CDK4, and cyclin D1. EGCG inhibits the growth of NCI-N87 cells in a time- and dose-dependent manner through arresting the cell cycle in the G0/G1 phase. Furthermore, terminal deoxynucleotidyl transferase dUTP nick end labeling assay and 4',6-diamidino-2-phenylindole staining revealed that EGCG is able to promote apoptosis of NCI-N87 cells. The suppressive effects of EGCG on cell growth and cell cycle protein expression are eliminated by decreasing KLF4 mRNA using siRNA and are magnified by overexpressing KLF4. Using KLF4 reporter constructs, we verified that the elevated expression induced by EGCG was mediated by increasing levels of activated MEF2A, which bound to the promoter region of KLF4. Taken together, this is the first time that EGCG is reported to increase the expression of KLF4, suggesting a novel mechanisms in gastric cancer treatment.
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Affiliation(s)
- Yuwen Ma
- />Department of Hepatobiliary Surgery, the Affiliated Hospital of WeiFang Medical University, No. 465 Yuhe Road, Kuiwen District, Weifang City, Shandong 261031 People’s Republic of China
| | - Youkui Shi
- />Department of Emergency Medicine, the Affiliated Hospital of WeiFang Medical University, No. 465 Yuhe Road, Kuiwen District, Weifang City, Shandong 261031 People’s Republic of China
| | - Wenmei Li
- />Department of Colorectal Surgery, the Affiliated Hospital of WeiFang Medical University, No. 465 Yuhe Road, Kuiwen District, Weifang City, Shandong 261031 People’s Republic of China
| | - Aijuan Sun
- />Department of Anesthesia, Qingdao Orthopaedics and Traumatology Hospital, No. 122 Taidong San Road, Qingdao, Shandong 266021 People’s Republic of China
| | - Ping Zang
- />Department of Nursing, the Affiliated Hospital of WeiFang Medical University, No. 465 Yuhe Road, Kuiwen District, Weifang City, Shandong 261031 People’s Republic of China
| | - Peirong Zhang
- />Department of Critical Care Medicine, the Affiliated Hospital of WeiFang Medical University, No. 465 Yuhe Road, Kuiwen District, Weifang City, Shandong 261031 People’s Republic of China
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Jain MK, Sangwung P, Hamik A. Regulation of an inflammatory disease: Krüppel-like factors and atherosclerosis. Arterioscler Thromb Vasc Biol 2014; 34:499-508. [PMID: 24526695 PMCID: PMC5539879 DOI: 10.1161/atvbaha.113.301925] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/07/2014] [Indexed: 12/13/2022]
Abstract
This invited review summarizes work presented in the Russell Ross lecture delivered at the 2012 proceedings of the American Heart Association. We begin with a brief overview of the structural, cellular, and molecular biology of Krüppel-like factors. We then focus on discoveries during the past decade, implicating Krüppel-like factors as key determinants of vascular cell function in atherosclerotic vascular disease.
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Affiliation(s)
- Mukesh K. Jain
- Case Cardiovascular Research Institute, Case Western Reserve University, and Harrington Heart and Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio, USA
| | - Panjamaporn Sangwung
- Case Cardiovascular Research Institute, Case Western Reserve University, and Harrington Heart and Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio, USA
| | - Anne Hamik
- Case Cardiovascular Research Institute, Case Western Reserve University, and Harrington Heart and Vascular Institute, University Hospitals Case Medical Center, Cleveland, Ohio, USA
- Division of Cardiovascular Medicine, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio
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Valencia-Hipόlito A, Hernández-Atenógenes M, Vega GG, Maldonado-Valenzuela A, Ramon G, Mayani H, Peña Alonso Y, Martinez-Maza O, Méndez-Tenorio A, Huerta-Yepez S, Bonavida B, Vega MI. Expression of KLF4 is a predictive marker for survival in pediatric Burkitt lymphoma. Leuk Lymphoma 2014; 55:1806-14. [PMID: 24067139 DOI: 10.3109/10428194.2013.848437] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Krüppel-like factor 4 (KLF4) is expressed in a variety of tissues with diverse physiological functions and activities. KLF4 can also function as a tumor suppressor or an oncogene, depending on the cellular context. Its role in hematological malignancies is controversial. This study examined the expression levels of KLF4 by immunohistochemistry in 73 pediatric non-Hodgkin lymphomas (NHLs) in a tissue microarray and also on several B-NHL cell lines. Elevated levels of KLF4 expression were detected in 66% of lymphoma cases and were more frequent in the Burkitt lymphoma (p = 0.05) subtype. There was a significant predictive power for outcome with low KLF4 expression, predicting a favorable overall survival compared to high levels. Multivariate analyses confirmed the association of KLF4 expression with unfavorable overall survival (p < 0.005). These findings were consistent with analyses in existing NHL microarray datasets. The present findings revealed that KLF4 is overexpressed in Burkitt pediatric lymphoma and is a potential biomarker for inferior overall survival.
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Affiliation(s)
- Alberto Valencia-Hipόlito
- Oncology Research Unit, Oncology Hospital, Siglo XXI National Medical Center , IMSS, Mexico City , Mexico
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Schoenhals M, Kassambara A, Veyrune JL, Moreaux J, Goldschmidt H, Hose D, Klein B. Krüppel-like factor 4 blocks tumor cell proliferation and promotes drug resistance in multiple myeloma. Haematologica 2013; 98:1442-9. [PMID: 23585530 DOI: 10.3324/haematol.2012.066944] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Krüppel-like factor 4 is a transcription factor with anti-proliferative effects in differentiated cells, but with the ability to reprogram adult cells into cell-cycling pluripotent cells. In cancer, Krüppel-like factor 4 acts as either an anti-oncogene or an oncogene. We analyzed Krüppel-like factor 4 gene expression in multiple myeloma using Affymetrix microarrays. We generated conditionally expressing Krüppel-like factor 4 myeloma cell lines to investigate the function of this gene in myeloma biology. Krüppel-like factor 4 gene expression is high in normal plasma cells, but reduced in primary multiple myeloma cells from two-thirds of patients. It is not expressed by any human myeloma cell line due to promoter methylation. Conditional expression of Krüppel-like factor 4 led to complete cell cycle blockade, mainly in G1 phase, with no major apoptosis. This blockade was associated with induction of p21(Cip1) and p27(Kip1) in cell lines with an intact p53 pathway, and of p27(Kip1) only in those with an impaired p53 pathway. Krüppel-like factor 4 is highly expressed in the poor prognostic MS group with t(4;14) translocation and in the good prognostic CD-1 group with t(11;14) or t(6;14). The apparent contradiction of cell cycle inhibitor Krüppel-like factor 4 expression in patients with poor prognosis could be reconciled since its expression increased the resistance of myeloma cell lines to melphalan. In conclusion, we describe for the first time that Krüppel-like factor 4 could play a critical role in controlling the cell cycle and resistance to alkylating agents in multiple myeloma cells.
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Hart GT, Hogquist KA, Jameson SC. Krüppel-like factors in lymphocyte biology. THE JOURNAL OF IMMUNOLOGY 2012; 188:521-6. [PMID: 22223851 DOI: 10.4049/jimmunol.1101530] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The Krüppel-like factor family of transcription factors plays an important role in differentiation, function, and homeostasis of many cell types. While their role in lymphocytes is still being determined, it is clear that these factors influence processes as varied as lymphocyte quiescence, trafficking, differentiation, and function. This review will present an overview of how these factors operate and coordinate with each other in lymphocyte regulation.
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Affiliation(s)
- Geoffrey T Hart
- Department of Laboratory Medicine and Pathology, Center for Immunology, University of Minnesota, Minneapolis, MN 55414, USA
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Moschovakis GL, Bubke A, Dittrich-Breiholz O, Braun A, Prinz I, Kremmer E, Förster R. Deficient CCR7 signaling promotes TH2 polarization and B-cell activation in vivo. Eur J Immunol 2011; 42:48-57. [PMID: 21969271 DOI: 10.1002/eji.201141753] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 08/16/2011] [Accepted: 09/27/2011] [Indexed: 12/23/2022]
Abstract
The chemokine receptor CCR7 has a central role in regulating homing and positioning of T cells and DCs to lymph nodes (LNs) and participates in T-cell development and activation. In this study, we addressed the role of CCR7 signaling in T(H) 2 polarization and B-cell activation. We provide evidence that the lack of CCR7 drives the capacity of naïve CD4(+) T cells to polarize toward T(H) 2 cells. This propensity contributes to a lymph node environment in CCR7-deficent mice characterized by increased expression of IL-4 and increased frequency of T(H) 2 cells. We show that elevated IL-4 levels lead to B-cell activation characterized by up-regulated expression of MHC class II, CD23 and CD86. Activated B cells are in turn highly efficient in presenting antigen to CD4(+) T cells and thus potentially contribute to the T(H) 2 microenvironment. Taken together, our results support the idea of a CCR7-dependent patterning of T(H) 2 responses, with absent CCR7 signaling favoring T(H) 2 polarization, dislocation of T helper cells into the B-cell follicles and, as a consequence, B-cell activation.
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Affiliation(s)
- G L Moschovakis
- Institute of Immunology, Hannover Medical School, Hannover, Germany
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Wen X, Liu H, Xiao G, Liu X. Downregulation of the transcription factor KLF4 is required for the lineage commitment of T cells. Cell Res 2011; 21:1701-10. [PMID: 22105482 DOI: 10.1038/cr.2011.183] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The roles of the reprogramming factors Oct4, Sox2, c-Myc and Klf4 in early T cell development are incompletely defined. Here, we show that Klf4 is the only reprogramming factor whose expression is downregulated when early thymic progenitors (ETPs) differentiate into T cells. Enforced expression of Klf4 in uncommitted progenitors severely impaired T cell development mainly at the DN2-to-DN3 transition when T cell lineage commitment occurs and affected the transcription of a variety of genes with crucial functions in early T cell development, including genes involved in microenvironmental signaling (IL-7Rα), Notch target genes (Deltex1), and essential T cell lineage regulatory or inhibitory genes (Bcl11a, SpiB, and Id1). The survival of thymocytes and the rearrangement at the Tcrb locus were impaired in the presence of enforced Klf4 expression. The defects in the DN1-to-DN2 and DN2-to-DN3 transitions in Klf4 transgenic mice could not be rescued by the introduction of a TCR transgene, but was partially rescued by restoring the expression of IL-7Rα. Thus, our data indicate that the downregulation of Klf4 is a prerequisite for T cell lineage commitment.
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Affiliation(s)
- Xiaomin Wen
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
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An J, Golech S, Klaewsongkram J, Zhang Y, Subedi K, Huston GE, Wood WH, Wersto RP, Becker KG, Swain SL, Weng N. Krüppel-like factor 4 (KLF4) directly regulates proliferation in thymocyte development and IL-17 expression during Th17 differentiation. FASEB J 2011; 25:3634-45. [PMID: 21685331 PMCID: PMC3177573 DOI: 10.1096/fj.11-186924] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 06/02/2011] [Indexed: 11/11/2022]
Abstract
Krüppel-like factor 4 (KLF4), a transcription factor, plays a key role in the pluripotency of stem cells. We sought to determine the function of KLF4 in T-cell development and differentiation by using T-cell-specific Klf4-knockout (KO) mice. We found that KLF4 was highly expressed in thymocytes and mature T cells and was rapidly down-regulated in mature T cells after activation. In Klf4-KO mice, we observed a modest reduction of thymocytes (27%) due to the reduced proliferation of double-negative (DN) thymocytes. We demonstrated that a direct repression of Cdkn1b by KLF4 was a cause of decreased DN proliferation. During in vitro T-cell differentiation, we observed significant reduction of IL-17-expressing CD4(+) T cells (Th17; 24%) but not in other types of Th differentiation. The reduction of Th17 cells resulted in a significant attenuation of the severity (35%) of experimental autoimmune encephalomyelitis in vivo in Klf4-KO mice as compared with the Klf4 wild-type littermates. Finally, we demonstrated that KLF4 directly binds to the promoter of Il17a and positively regulates its expression. In summary, these findings identify KLF4 as a critical regulator in T-cell development and Th17 differentiation.
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Affiliation(s)
- Jie An
- Laboratory of Molecular Biology and Immunology
| | | | | | | | | | - Gail E. Huston
- Trudeau Institute, Saranac Lake, New York, New York, USA; and
| | | | - Robert P. Wersto
- Flow Cytometry Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | | | - Susan L. Swain
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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Sur I. Krüppel-like factors 4 and 5: unity in diversity. Curr Genomics 2011; 10:594-603. [PMID: 20514221 PMCID: PMC2817890 DOI: 10.2174/138920209789503932] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/26/2009] [Accepted: 08/06/2009] [Indexed: 12/17/2022] Open
Abstract
Krüppel-like factors (Klf) 4 and 5 belong to a family of zinc finger-containing transcription factors that share homology with the Drosophila gene Krüppel. They regulate proliferation and differentiation of a wide variety of cells and have been linked to tumorigenesis. Their most striking role so far has turned out to be their ability to reprogram/ maintain embryonic stem cell fate. In this review, the data available in the field regarding their role in proliferation and differentiation and their coupling to carcinogenesis are summarized. The emphasis is on their context dependence and how they might be able to regulate diverse transcriptional outputs from the genome.
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Affiliation(s)
- Inderpreet Sur
- Department of Biosciences and Nutrition, Karolinska Institutet, SE 141 57 Huddinge, Sweden
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Expression of aryl hydrocarbon receptor and aryl hydrocarbon receptor nuclear translocators in human adenoid tissue. Auris Nasus Larynx 2011; 38:352-5. [DOI: 10.1016/j.anl.2010.09.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2009] [Revised: 08/13/2010] [Accepted: 09/20/2010] [Indexed: 01/19/2023]
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Abstract
The Krüppel-like factor (KLF) family of transcription factors regulates diverse biological processes that include proliferation, differentiation, growth, development, survival, and responses to external stress. Seventeen mammalian KLFs have been identified, and numerous studies have been published that describe their basic biology and contribution to human diseases. KLF proteins have received much attention because of their involvement in the development and homeostasis of numerous organ systems. KLFs are critical regulators of physiological systems that include the cardiovascular, digestive, respiratory, hematological, and immune systems and are involved in disorders such as obesity, cardiovascular disease, cancer, and inflammatory conditions. Furthermore, KLFs play an important role in reprogramming somatic cells into induced pluripotent stem (iPS) cells and maintaining the pluripotent state of embryonic stem cells. As research on KLF proteins progresses, additional KLF functions and associations with disease are likely to be discovered. Here, we review the current knowledge of KLF proteins and describe common attributes of their biochemical and physiological functions and their pathophysiological roles.
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Affiliation(s)
- Beth B McConnell
- Departments of Medicine and of Hematology and Medical Oncology, Emory University School of Medicine,Atlanta, Georgia 30322, USA
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Abstract
The Krüppel-like transcription factor (KLF) family participates in diverse aspects of cellular growth, development, differentiation, and activation. Recently, several groups have identified new connections between the function of these factors and leukocyte responses in health and disease. Gene targeting of individual KLFs in mice has uncovered novel and unexpected physiologic roles among myeloid and lymphocyte cell lineage maturation, particularly in the bone marrow niche and blood. In addition, several KLF family members are downstream targets of stimuli and signaling pathways critical to T-cell trafficking, T regulatory cell differentiation or suppressor function, monocyte/macrophage activation or renewal, and B memory cell maturation or activation. Indeed, KLFs have been implicated in subtypes of leukemia, lymphoma, autoimmunity, and in acute and chronic inflammatory disease states, such as atherosclerosis, diabetes, and airway inflammation, raising the possibility that KLFs and their upstream signals are of therapeutic interest. This review focuses on the relevant literature of Krüppel-like factors in leukocyte biology and their implications in clinical settings.
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Abstract
The transcription factor KLF4 may act both as an oncogene and a tumor suppressor in a tissue-depending manner. In T- and pre-B-cell lymphoma, KLF4 was found to act as tumor suppressor. We found the KLF4 promoter methylated in B-cell lymphoma cell lines and in primary cases of B-cell lymphomas, namely, follicular lymphoma, diffuse large B-cell lymphoma, Burkitt lymphoma, and in classic Hodgkin lymphoma (cHL) cases. Promoter hypermethylation was associated with silencing of KLF4 expression. Conditional overexpression of KLF4 in Burkitt lymphoma cell lines moderately retarded proliferation, via cell-cycle arrest in G(0)/G(1). In the cHL cell lines, KLF4 induced massive cell death that could partially be inhibited with Z-VAD.fmk. A quantitative reverse-transcribed polymerase chain reaction array revealed KLF4 target genes, including the proapoptotic gene BAK1. Using an shRNA-mediated knock-down approach, we found that BAK1 is largely responsible for KLF4-induced apoptosis. In addition, we found that KLF4 negatively regulates CXCL10, CD86, and MSC/ABF-1 genes. These genes are specifically up-regulated in HRS cells of cHL and known to be involved in establishing the cHL phenotype. We conclude that epigenetic silencing of KLF4 in B-cell lymphomas and particularly in cHL may favor lymphoma survival by loosening cell-cycle control and protecting from apoptosis.
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Genetic and epigenetic inactivation of Kruppel-like factor 4 in medulloblastoma. Neoplasia 2010; 12:20-7. [PMID: 20072650 DOI: 10.1593/neo.91122] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 09/17/2009] [Accepted: 09/18/2009] [Indexed: 01/18/2023] Open
Abstract
Although medulloblastoma is the most common pediatric malignant brain tumor, its molecular underpinnings are largely unknown. We have identified rare, recurrent homozygous deletions of Kruppel-like Factor 4 (KLF4) in medulloblastoma using high-resolution single nucleotide polymorphism arrays, digital karyotyping, and genomic real-time polymerase chain reaction (PCR). Furthermore, we show that there is loss of physiological KLF4 expression in more than 40% of primary medulloblastomas both at the RNA and protein levels. Medulloblastoma cell lines drastically increase the expression of KLF4 in response to the demethylating agent 5-azacytidine and demonstrate dense methylation of the promoter CpG island by bisulfite sequencing. Methylation-specific PCR targeting the KLF4 promoter demonstrates CpG methylation in approximately 16% of primary medulloblastomas. Reexpression of KLF4 in the D283 medulloblastoma cell line results in significant growth suppression both in vitro and in vivo. We conclude that KLF4 is inactivated by either genetic or epigenetic mechanisms in a large subset of medulloblastomas and that it likely functions as a tumor suppressor gene in the pathogenesis of medulloblastoma.
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Godmann M, Kosan C, Behr R. Krüppel-like factor 4 is widely expressed in the mouse male and female reproductive tract and responds as an immediate early gene to activation of the protein kinase A in TM4 Sertoli cells. Reproduction 2010; 139:771-82. [PMID: 20051481 DOI: 10.1530/rep-09-0531] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Krüppel-like factor 4 (KLF4) is a zinc finger transcription factor critically involved in cell proliferation, differentiation, and carcinogenesis. Recently, KLF4 has also been used for the generation of induced pluripotent stem cells. In this study, we analyzed Klf4 expression in different mouse tissues using northern blot analysis and immunohistochemistry. Focusing on the male and female reproductive tract, we showed for the first time that KLF4 is expressed in the epithelia of the murine uterus and the vagina. In the male reproductive tract, we detected KLF4 in the epithelia of the epididymis, ductus deferens, coagulating gland, and the penis. As KLF4 is strongly inducible by FSH signaling in Sertoli cells and as this transcription factor is also involved in Sertoli cell development, we employed the mouse Sertoli cell line TM4 as a model system to investigate i) the induction kinetics of Klf4 upon activation of the cAMP/protein kinase A pathway by forskolin and ii) the effects of Klf4 induction on TM4 cell cycle progression. Interestingly, Klf4 mRNA and protein were rapidly but transiently induced, reaching peak levels after 90-120 min and declining to basal levels within 4 h. Compared with the inducible cAMP early repressor, an immediate early response gene, the induction kinetics of Klf4 is much faster. In conclusion, Klf4 is an immediate early gene in TM4 cells and its expression in several epithelia of the male and female reproductive tract suggests an important role of Klf4 in mouse reproductive functions.
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Affiliation(s)
- M Godmann
- Institute of Anatomy, Developmental Biology, University of Duisburg-Essen Medical School, Essen, Germany
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White LJ, Declercq W, Arfuso F, Charles AK, Dharmarajan AM. Function of caspase-14 in trophoblast differentiation. Reprod Biol Endocrinol 2009; 7:98. [PMID: 19747408 PMCID: PMC2753366 DOI: 10.1186/1477-7827-7-98] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Accepted: 09/14/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Within the human placenta, the cytotrophoblast consists of a proliferative pool of progenitor cells which differentiate to replenish the overlying continuous, multi-nucleated syncytiotrophoblast, which forms the barrier between the maternal and fetal tissues. Disruption to trophoblast differentiation and function may result in impaired fetal development and preeclampsia. Caspase-14 expression is limited to barrier forming tissues. It promotes keratinocyte differentiation by cleaving profilaggrin to stabilise keratin intermediate filaments, and indirectly providing hydration and UV protection. However its role in the trophoblast remains unexplored. METHODS Using RNA Interference the reaction of control and differentiating trophoblastic BeWo cells to suppressed caspase-14 was examined for genes pertaining to hormonal, cell cycle and cytoskeletal pathways. RESULTS Transcription of hCG, KLF4 and cytokeratin-18 were increased following caspase-14 suppression suggesting a role for caspase-14 in inhibiting their pathways. Furthermore, hCG, KLF4 and cytokeratin-18 protein levels were disrupted. CONCLUSION Since expression of these molecules is normally increased with trophoblast differentiation, our results imply that caspase-14 inhibits trophoblast differentiation. This is the first functional study of this unusual member of the caspase family in the trophoblast, where it has a different function than in the epidermis. This knowledge of the molecular underpinnings of trophoblast differentiation may instruct future therapies of trophoblast disease.
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Affiliation(s)
- Lloyd J White
- School of Anatomy and Human Biology, Faculty of Life and Physical Sciences, The University of Western Australia, 35 Stirling Hwy Crawley, Perth, Western Australia 6009, Australia
| | - Wim Declercq
- Department of Molecular Biology, Ghent University, Technologie Park 927, B-9052, Ghent, Belgium
| | - Frank Arfuso
- School of Anatomy and Human Biology, Faculty of Life and Physical Sciences, The University of Western Australia, 35 Stirling Hwy Crawley, Perth, Western Australia 6009, Australia
| | - Adrian K Charles
- King Edward Memorial Hospital for Women (KEMH), 374 Bagot Rd, Subiaco, Western Australia 6008, Australia
| | - Arun M Dharmarajan
- School of Anatomy and Human Biology, Faculty of Life and Physical Sciences, The University of Western Australia, 35 Stirling Hwy Crawley, Perth, Western Australia 6009, Australia
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Godmann M, Gashaw I, Katz JP, Nagy A, Kaestner KH, Behr R. Krüppel-like factor 4, a "pluripotency transcription factor" highly expressed in male postmeiotic germ cells, is dispensable for spermatogenesis in the mouse. Mech Dev 2009; 126:650-64. [PMID: 19539755 DOI: 10.1016/j.mod.2009.06.1081] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 06/10/2009] [Accepted: 06/11/2009] [Indexed: 02/07/2023]
Abstract
Krüppel-like factor 4 (Klf4, GKLF) was originally characterized as a zinc finger transcription factor essential for terminal differentiation and cell lineage allocation of several cell types in the mouse. Mice lacking Klf4 die postnatally within hours due to impaired skin barrier function and subsequent dehydration. Recently, KLF4 was also used in cooperation with other transcription factors to reprogram differentiated cells to pluripotent embryonic stem cell-like cells. Moreover, involvement in oncogenesis was also ascribed to KLF4, which is aberrantly expressed in some types of tumors such as breast, gastric and colon cancer. We previously have shown that Klf4 is strongly expressed in postmeiotic germ cells of mouse and human testes suggesting a role for Klf4 also during spermiogenesis. In order to analyze its function we deleted Klf4 in germ cells using the Cre-loxP system. Homologous recombination of the Klf4 locus has been confirmed by genomic southern blotting and the absence of the protein in germ cells was demonstrated by Western blotting and immunofluorescence. Despite its important roles in several significant biological settings, deletion of Klf4 in germ cells did not impair spermiogenesis. Histologically, the mutant testes appeared normal and the mice were fertile. In order to identify genes that were regulated by KLF4 in male germ cells we performed microarray analyses using a whole genome array. We identified many genes exhibiting changed expression in mutants even including the telomerase reverse transcriptase mRNA, which is a stem cell marker. However, in summary, the lack of KLF4 alone does not prevent complete spermatogenesis.
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Affiliation(s)
- Maren Godmann
- Institute of Anatomy, Developmental Biology, Hufelandstrasse 55, University of Duisburg-Essen Medical School, 45122 Essen, Germany
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Godmann M, Gashaw I, Eildermann K, Schweyer S, Bergmann M, Skotheim RI, Behr R. The pluripotency transcription factor Krüppel-like factor 4 is strongly expressed in intratubular germ cell neoplasia unclassified and seminoma. Mol Hum Reprod 2009; 15:479-88. [PMID: 19505997 DOI: 10.1093/molehr/gap040] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Germ cell tumors of the testis are the most frequent tumors in men between 20 and 40 years. Their most common subtype is the seminoma, which arises like the embryonal carcinoma from an intratubular germ cell neoplasia unclassified (IGCNU), i.e. fetal germ cells that escaped from the control of the developing testicular stem cell niche, eventually leading to a fully developed seminoma (or embryonal carcinoma). The molecular causes for the development of an IGCNU are still unknown. However, IGCNU cells share the expression of several factors with primordial germ cells and gonocytes and, interestingly, also with pluripotent embryonic stem (ES) cells and induced pluripotent stem (iPS) cells. One factor playing important roles in both iPS and ES cells is the transcription factor Krüppel-like factor 4 (KLF4). This study examined KLF4 expression data from 179 human testicular samples including normal controls and seminoma, deposited in Gene Expression Omnibus repository for microarray data at the National Centre for Biotechnology Information. Immunohistochemistry was used to detect KLF4 protein expression in IGCNU (n = 6), seminoma (n = 14) and fetal human testes (n = 14). Microarray data from three independent sources suggest higher mRNA expression in seminoma than in normal testis. Normal spermatogonia, which are the stem cells of spermatogenesis, controlled by their stem cell niche, do not express KLF4. In contrast, IGCNU and seminoma cells strongly express KLF4. In conclusion, this finding suggests that KLF4 may be an important factor for the maintenance of the developmental and the tumorigenic potential of IGCNU as well as for the malignancy of seminoma.
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Affiliation(s)
- M Godmann
- Department of Animal Science, McGill University, Macdonald Campus, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, QC, Canada
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Bai Y, Liu R, Huang D, La Cava A, Tang YY, Iwakura Y, Campagnolo DI, Vollmer TL, Ransohoff RM, Shi FD. CCL2 recruitment of IL-6-producing CD11b+ monocytes to the draining lymph nodes during the initiation of Th17-dependent B cell-mediated autoimmunity. Eur J Immunol 2008; 38:1877-88. [PMID: 18581322 DOI: 10.1002/eji.200737973] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The development and function of Th17 cells are influenced in part by the cytokines TGF-beta, IL-23 and IL-6, but the mechanisms that govern recruitment and activity of Th17 cells during initiation of autoimmunity remain poorly defined. We show here that the development of autoreactive Th17 cells in secondary lymphoid organs in experimental autoimmune myasthenia gravis--an animal model of human myasthenia gravis--is modulated by IL-6-producing CD11b(+) cells via the CC chemokine ligand 2 (CCL2). Notably, acetylcholine receptor (AChR)-reactive Th17 cells provide help for the B cells to produce anti-AChR antibodies, which are responsible for the impairment of the neuromuscular transmission that contributes to the clinical manifestations of autoimmunity, as indicated by a lack of disease induction in IL-17-deficient mice. Thus, Th17 cells can promote humoral autoimmunity via a novel mechanism that involves CCL2.
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Affiliation(s)
- Ying Bai
- Institute of Neuroinformatics and Laboratory for Brain and Mind, Dalian University of Technology, Dalian, China
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Evans PM, Liu C. Roles of Krüpel-like factor 4 in normal homeostasis, cancer and stem cells. Acta Biochim Biophys Sin (Shanghai) 2008; 40:554-64. [PMID: 18604447 DOI: 10.1111/j.1745-7270.2008.00439.x] [Citation(s) in RCA: 155] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Krüpel-like factor 4 (KLF4) is a zinc finger-type transcription factor expressed in a variety of tissues, including the epithelium of the intestine and the skin, and it plays an important role in differentiation and cell cycle arrest. Depending on the gene targeted, KLF4 can both activate and repress transcription. Moreover, in certain cellular contexts, KLF4 can function as a tumor suppressor or an oncogene. Finally, KLF4 is important in reprogramming differentiated fibroblasts into inducible pluripotent stem cells, which highly resemble embryonic stem cells. This review summarizes what is known about the diverse functions of KLF4 as well as their molecular mechanisms.
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Affiliation(s)
- Paul M Evans
- Department of Biochemistry and Molecular Biology, Sealy Center for Cancer Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555-1448, USA
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Yusuf I, Kharas MG, Chen J, Peralta RQ, Maruniak A, Sareen P, Yang VW, Kaestner KH, Fruman DA. KLF4 is a FOXO target gene that suppresses B cell proliferation. Int Immunol 2008; 20:671-81. [DOI: 10.1093/intimm/dxn024] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Godmann M, Katz JP, Guillou F, Simoni M, Kaestner KH, Behr R. Krüppel-like factor 4 is involved in functional differentiation of testicular Sertoli cells. Dev Biol 2008; 315:552-66. [PMID: 18243172 DOI: 10.1016/j.ydbio.2007.12.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 12/14/2007] [Accepted: 12/14/2007] [Indexed: 02/03/2023]
Abstract
Krüppel-like factor 4 (KLF4) is a pleiotropic zinc finger transcription factor that regulates genes being involved in differentiation and cell-cycle control. Knockout studies revealed a critical function for KLF4 in the terminal differentiation of many epithelial cells. In testicular Sertoli cells, Klf4 is strongly inducible by the glycoprotein follicle stimulating hormone (FSH). Because KLF4 is essential for postnatal survival in mice, we deleted Klf4 specifically in Sertoli cells using the Cre/loxP system. Importantly, around postnatal day 18, a critical period of terminal Sertoli cell differentiation, mutant seminiferous tubules exhibited a disorganized germinal epithelium and delayed lumen formation. The ultrastructural finding of highly vacuolized Sertoli cell cytoplasm and the identification of differentially expressed genes, which are known to play roles during vesicle transport and fusion or for maintenance of the differentiated cell state, suggest impaired apical secretion of the Sertoli cell. Interestingly, a high proportion of all identified genes was localized in a small subregion of chromosome 7, suggesting coordinated regulation. Intriguingly, adult mutant mice are fertile and show normal testicular morphology, although the testosterone levels are decreased. In summary, KLF4 plays a significant role for proper and timely Sertoli cell differentiation in pubertal mice.
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Affiliation(s)
- Maren Godmann
- Institute of Anatomy, Developmental Biology, University of Duisburg-Essen Medical School, 45122 Essen, Germany
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