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Jha K, Kumar A, Bhatnagar K, Patra A, Bhavesh NS, Singh B, Chaudhary S. Modulation of Krüppel-like factors (KLFs) interaction with their binding partners in cancers through acetylation and phosphorylation. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195003. [PMID: 37992989 DOI: 10.1016/j.bbagrm.2023.195003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/05/2023] [Accepted: 11/16/2023] [Indexed: 11/24/2023]
Abstract
Post-translational modifications (PTMs) of transcription factors regulate transcriptional activity and play a key role in essentially all biological processes and generate indispensable insight towards biological function including activity state, subcellular localization, protein solubility, protein folding, substrate trafficking, and protein-protein interactions. Amino acids modified chemically via PTMs, function as molecular switches and affect the protein function and characterization and increase the proteome complexity. Krüppel-like transcription factors (KLFs) control essential cellular processes including proliferation, differentiation, migration, programmed cell death and various cancer-relevant processes. We investigated the interactions of KLF group-2 members with their binding partners to assess the role of acetylation and phosphorylation in KLFs on their binding affinity. It was observed that acetylation and phosphorylation at different positions in KLFs have a variable effect on binding with specific partners. KLF2-EP300, KLF4-SP1, KLF6-ATF3, KLF6-JUN, and KLF7-JUN show stabilization upon acetylation or phosphorylation at variable positions. On the other hand, KLF4-CBP, KLF4-EP300, KLF5-CBP, KLF5-WWP1, KLF6-SP1, and KLF7-ATF3 show stabilization or destabilization due to acetylation or phosphorylation at variable positions in KLFs. This provides a molecular explanation of the experimentally observed dual role of KLF group-2 members as a suppressor or activator of cancers in a PTM-dependent manner.
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Affiliation(s)
- Kanupriya Jha
- Department of Biotechnology, School of Engineering and Applied Sciences, Bennett University, Plot Nos. 8-11, Tech Zone 2, Greater Noida, Uttar Pradesh 201310, India.
| | - Amit Kumar
- Department of Biotechnology, School of Engineering and Applied Sciences, Bennett University, Plot Nos. 8-11, Tech Zone 2, Greater Noida, Uttar Pradesh 201310, India.
| | - Kartik Bhatnagar
- Department of Biotechnology, School of Engineering and Applied Sciences, Bennett University, Plot Nos. 8-11, Tech Zone 2, Greater Noida, Uttar Pradesh 201310, India.
| | - Anupam Patra
- Transcription Regulation Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India.
| | - Neel Sarovar Bhavesh
- Transcription Regulation Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India.
| | - Bipin Singh
- Department of Biotechnology, School of Engineering and Applied Sciences, Bennett University, Plot Nos. 8-11, Tech Zone 2, Greater Noida, Uttar Pradesh 201310, India; Centre for Life Sciences, Mahindra University, Bahadurpally, Jeedimetla, Hyderabad, Telangana 500043, India.
| | - Sarika Chaudhary
- Department of Biotechnology, School of Engineering and Applied Sciences, Bennett University, Plot Nos. 8-11, Tech Zone 2, Greater Noida, Uttar Pradesh 201310, India.
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Yuce K, Ozkan AI. The kruppel-like factor (KLF) family, diseases, and physiological events. Gene 2024; 895:148027. [PMID: 38000704 DOI: 10.1016/j.gene.2023.148027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 11/06/2023] [Accepted: 11/21/2023] [Indexed: 11/26/2023]
Abstract
The Kruppel-Like Factor family of regulatory proteins, which has 18 members, is transcription factors. This family contains zinc finger proteins, regulates the activation and suppression of transcription, and binds to DNA, RNA, and proteins. Klfs related to the immune system are Klf1, Klf2, Klf3, Klf4, Klf6, and Klf14. Klfs related to adipose tissue development and/or glucose metabolism are Klf3, Klf7, Klf9, Klf10, Klf11, Klf14, Klf15, and Klf16. Klfs related to cancer are Klf3, Klf4, Klf5, Klf6, Klf7, Klf8, Klf9, Klf10, Klf11, Klf12, Klf13, Klf14, Klf16, and Klf17. Klfs related to the cardiovascular system are Klf4, Klf5, Klf10, Klf13, Klf14, and Klf15. Klfs related to the nervous system are Klf4, Klf7, Klf8, and Klf9. Klfs are associated with diseases such as carcinogenesis, oxidative stress, diabetes, liver fibrosis, thalassemia, and the metabolic syndrome. The aim of this review is to provide information about the relationship of Klfs with some diseases and physiological events and to guide future studies.
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Affiliation(s)
- Kemal Yuce
- Selcuk University, Medicine Faculty, Department of Basic Medical Sciences, Physiology, Konya, Turkiye.
| | - Ahmet Ismail Ozkan
- Artvin Coruh University, Medicinal-Aromatic Plants Application and Research Center, Artvin, Turkiye.
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Le Minh G, Esquea EM, Dhameliya TT, Merzy J, Lee MH, Ball LE, Reginato MJ. Kruppel-like factor 8 regulates triple negative breast cancer stem cell-like activity. Front Oncol 2023; 13:1141834. [PMID: 37152043 PMCID: PMC10155275 DOI: 10.3389/fonc.2023.1141834] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/29/2023] [Indexed: 05/09/2023] Open
Abstract
Introduction Breast tumor development is regulated by a sub-population of breast cancer cells, termed cancer stem-like cells (CSC), which are capable of self-renewing and differentiating, and are involved in promoting breast cancer invasion, metastasis, drug resistance and relapse. CSCs are highly adaptable, capable of reprogramming their own metabolism and signaling activity in response to stimuli within the tumor microenvironment. Recently, the nutrient sensor O-GlcNAc transferase (OGT) and O-GlcNAcylation was shown to be enriched in CSC populations, where it promotes the stemness and tumorigenesis of breast cancer cells in vitro and in vivo. This enrichment was associated with upregulation of the transcription factor Kruppel-like-factor 8 (KLF8) suggesting a potential role of KLF8 in regulating CSCs properties. Methods Triple-negative breast cancer cells were genetically modified to generate KLF8 overexpressing or KLF8 knock-down cells. Cancer cells, control or with altered KLF8 expression were analyzed to assess mammosphere formation efficiency, CSCs frequency and expression of CSCs factors. Tumor growth in vivo of control or KLF8 knock-down cells was assessed by fat-pad injection of these cell in immunocompromised mice. Results Here, we show that KLF8 is required and sufficient for regulating CSC phenotypes and regulating transcription factors SOX2, NANOG, OCT4 and c-MYC. KLF8 levels are associated with chemoresistance in triple negative breast cancer patients and overexpression in breast cancer cells increased paclitaxel resistance. KLF8 and OGT co-regulate each other to form a feed-forward loop to promote CSCs phenotype and mammosphere formation of breast cancer cells. Discussion These results suggest a critical role of KLF8 and OGT in promoting CSCs and cancer progression, that may serve as potential targets for developing strategy to target CSCs specifically.
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Affiliation(s)
- Giang Le Minh
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Emily M. Esquea
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Tejsi T. Dhameliya
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Jessica Merzy
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Mi-Hye Lee
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, United States
| | - Lauren E. Ball
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, United States
| | - Mauricio J. Reginato
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, United States
- Translational and Cellular Oncology Program, Sidney Kimmel Cancer Center of Thomas Jefferson University, Philadelphia, PA, United States
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Kruppel-like Factors in Skeletal Physiology and Pathologies. Int J Mol Sci 2022; 23:ijms232315174. [PMID: 36499521 PMCID: PMC9741390 DOI: 10.3390/ijms232315174] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/11/2022] Open
Abstract
Kruppel-like factors (KLFs) belong to a large group of zinc finger-containing transcription factors with amino acid sequences resembling the Drosophila gap gene Krüppel. Since the first report of molecular cloning of the KLF family gene, the number of KLFs has increased rapidly. Currently, 17 murine and human KLFs are known to play crucial roles in the regulation of transcription, cell proliferation, cellular differentiation, stem cell maintenance, and tissue and organ pathogenesis. Recent evidence has shown that many KLF family molecules affect skeletal cells and regulate their differentiation and function. This review summarizes the current understanding of the unique roles of each KLF in skeletal cells during normal development and skeletal pathologies.
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CircRNA PVT1 promotes proliferation and chemoresistance of osteosarcoma cells via the miR-24-3p/KLF8 axis. Int J Clin Oncol 2022; 27:811-822. [PMID: 35171359 DOI: 10.1007/s10147-022-02122-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 01/13/2022] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the regulatory effect and mechanism of circular RNA PVT1 (circPVT1) in proliferation and chemoresistance of osteosarcoma (OS) cells. METHODS The expression of circPVT1 in human OS and adjacent normal tissues was detected. The correlation between circPVT1 expression and clinical features of OS was analyzed. The expressions of circPVT1 and miR-24-3p in OS cells resistant to cisplatin, doxorubicin or methotrexate and parental OS cells were detected after cell transfection. CCK-8 and colony formation assay assessed the viability and proliferative ability of OS cells. qRT-PCR and Western blotting measured the expression of KLF8. Dual-luciferase reporter and RNA pull-down assays verified the targeting relationships of circPVT1/miR-24-3p and miR-24-3p/KLF8. RESULTS CircPVT1 was over-expressed in OS tissues and cells, and correlated with clinical features of OS. Over-expressed circPVT1 reduced the survival of OS patients. CircPVT1 was up-regulated in chemoresistant OS cells compared to their parental cells. CircPVT1 inhibition suppressed the proliferation and chemoresistance of OS cells. MiR-24-3p was under-expressed in OS cells and further down-regulated in chemoresistant cells. CircPVT1 could bind and down-regulate miR-24-3p. MiR-24-3p overexpression inhibited the proliferation and chemoresistance of OS cells. KLF8 was over-expressed in OS cells and further up-regulated in chemoresistant cells. MiR-24-3p negatively regulated the expression of KLF8. CONCLUSION CircPVT1 mediates proliferation and chemoresistance of OS cells via the miR-24-3p/KLF8 axis. The findings may provide guidance for clinical treatment of OS.
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Qu X, Liu X, Zhang Y, Shi Z, Wang X. Depletion of Kruppel-like factor 15 sensitized gliomas to temozolomide cytotoxicity through O 6-methylguanine-DNA methyl-transferase. Biochem Biophys Rep 2021; 27:101058. [PMID: 34222684 PMCID: PMC8242961 DOI: 10.1016/j.bbrep.2021.101058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/08/2021] [Accepted: 06/11/2021] [Indexed: 11/29/2022] Open
Abstract
Temozolomide (TMZ)-based chemotherapy is a standard strategy for gliomas, although chemoresistance remains a major therapeutic challenge. The chemical mechanism by which TMZ induces cell death is DNA methylation, leading to double-stranded breaks (DSBs) and thus to apoptosis. However, TMZ-induced N6-meG sites are efficiently repaired and mediated by the DNA repair protein O 6-methylguanine-DNA methyl-transferase (MGMT), leading to TMZ resistance. KLF15, a member of the Kruppel-like factors family, mainly functions as transcription factor and potential suppressor gene by inhibiting proliferation, migration, and inducing apoptosis. However, the roles and regulatory mechanisms of KLF15 in glioma tumorigenesis and chemoresistance are poorly understood. In this study, KLF15 expression was upregulated in glioma tissues and cell lines upon TMZ treatment. Knockdown of KLF15 amplified TMZ-induced repression of cell proliferation, while KLF15 overexpression reversed this process. Mechanistically, KLF15 functioned as a transcriptional activator of MGMT. Moreover, KLF15 knockdown sensitized tumors to TMZ treatment in vivo. Taken together, these results suggested that KLF15 up-regulated MGMT through direct binding to the promoter of MGMT, which plays an important role in glioma resistance to TMZ, and which may be a potential target for cancer diagnosis and treatment.
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Affiliation(s)
- Xinjuan Qu
- Department of Neurosurgery, Linyi Hospital of Traditional Chinese Medicine, Shandong, 276002, China
| | - Xuelai Liu
- Department of Neurosurgery, Linyi Hospital of Traditional Chinese Medicine, Shandong, 276002, China
| | - Yumei Zhang
- Department of Neurology, Linyi Hospital of Traditional Chinese Medicine, Shandong, 276002, China
| | - Zhan Shi
- The Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University, Clinical Cancer Institute of Nanjing University, Nanjing, 210002, China
| | - Xiaohua Wang
- Department of General Internal Medicine, Linyi People's Hospital, Shandong, 276003, China
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Zhu P, Liu HY, Liu FC, Gu FM, Yuan SX, Huang J, Pan ZY, Wang WJ. Circulating Tumor Cells Expressing Krüppel-Like Factor 8 and Vimentin as Predictors of Poor Prognosis in Pancreatic Cancer Patients. Cancer Control 2021; 28:10732748211027163. [PMID: 34378430 PMCID: PMC8361509 DOI: 10.1177/10732748211027163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Circulating tumor cells (CTCs) with an epithelial-mesenchymal transition phenotype in peripheral blood may be a useful marker of carcinomas with poor prognosis. The aim of this study was to determine the prognostic significance of CTCs expressing Krüppel-like factor 8 (KLF8) and vimentin in pancreatic cancer (PC). METHODS CTCs were isolated by immunomagnetic separation from the peripheral blood of 40 PC patients before undergoing surgical resection. Immunocytochemistry was performed to identify KLF8+ and vimentin+ CTCs. The associations between CTCs and time to recurrence (TTR), clinicopathologic factors, and survival were assessed. Univariate and multivariate analyzes were performed to identify risk factors. RESULTS Patients with CTCs (n = 30) had a higher relapse rate compared to those without (n = 10) (70.0% vs 20.0%; P < 0.01). The proportion of KLF8+/vimentin+ CTCs to total CTCs was inversely related to TTR (r = -0.646; P < 0.01); TTR was reduced in patients with > 50% of CTCs identified as KLF8+/vimentin+ (P < 0.01). Independent risk factors for recurrence were perineural invasion and > 50% KLF8+/vimentin+ CTCs (both P < 0.05). CONCLUSION Poor prognosis can be predicted in PC patients when > 50% of CTCs are positive for KLF8 and vimentin.
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Affiliation(s)
- Peng Zhu
- Department of Hepatic Surgery (III), Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Hui-Ying Liu
- Department of Biotherapy, Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Fu-Chen Liu
- Department of Hepatic Surgery (III), Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Fang-Ming Gu
- Department of Hepatic Surgery (III), Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Sheng-Xian Yuan
- Department of Hepatic Surgery (III), Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Jian Huang
- Department of Hepatic Surgery (III), Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Ze-Ya Pan
- Department of Hepatic Surgery (III), Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Wei-Jun Wang
- Department of Gastrointestinal Surgery, Second Affiliated Hospital of Naval Medical University, Shanghai, China
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Wei W, Ji L, Duan W, Zhu J. CircSAMD4A contributes to cell doxorubicin resistance in osteosarcoma by regulating the miR-218-5p/KLF8 axis. Open Life Sci 2020; 15:848-859. [PMID: 33817271 PMCID: PMC7747519 DOI: 10.1515/biol-2020-0079] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 06/16/2020] [Accepted: 07/19/2020] [Indexed: 02/06/2023] Open
Abstract
Circular RNA sterile alpha motif domain containing 4A (circSAMD4A) was found to be differentially expressed in osteosarcoma and contributed to the tumorigenesis of osteosarcoma. However, the role of circSAMD4A in doxorubicin (DXR) resistance of osteosarcoma is yet to be elucidated. Levels of circSAMD4A, microRNA (miR)-218-5p and Krüppel-like factor 8 (KLF8) were detected using quantitative reverse transcription-polymerase chain reaction. Western blot was applied to detect the protein levels of KLF8, cyclin D1 and p21. Cell viability, cell cycle, migration and invasion were analyzed using Cell Counting Kit-8 assay, flow cytometry and transwell assay, respectively. The interaction between miR-218-5p and circSAMD4A or KLF8 was verified using dual-luciferase reporter assay or RNA immunoprecipitation assay. In vivo experiments were performed using murine xenograft models. CircSAMD4A and KLF8 were elevated in osteosarcoma, and knockdown of circSAMD4A or KLF8 sensitized osteosarcoma cells to DXR by mediating resistant cell viability, migration and invasion inhibition, and cell cycle arrest in vitro. miR-218-5p was decreased in osteosarcoma, and miR-218-5p inhibition enhanced DXR resistance. Besides, miR-218-5p was found to bind to circSAMD4A or KLF8, and subsequent rescue experiments indicated that miR-218-5p inhibition reversed the inhibitory effects of circSAMD4A silencing on DXR resistance, and silencing miR-218-5p enhanced DXR resistance by targeting KLF8 in osteosarcoma cells. Moreover, circSAMD4A could indirectly regulate KLF8 via miR-218-5p. Additionally, circSAMD4A knockdown enhanced the cytotoxicity of DXR in osteosarcoma in vivo via regulating miR-218-5p and KLF8. In all, circSAMD4A enhanced cell DXR resistance in osteosarcoma by regulating the miR-218-5p/KLF8 axis, suggesting a novel therapeutic target for therapy-resistant osteosarcoma.
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Affiliation(s)
- Wei Wei
- Department of orthopedics, Shaoxing Shangyu People's Hospital, No. 517, Shimin Avenue, Baiguan Street, Shangyu District, Shaoxing, Zhejiang Province, 312300, China
| | - Liefeng Ji
- Department of orthopedics, Shaoxing Shangyu People's Hospital, No. 517, Shimin Avenue, Baiguan Street, Shangyu District, Shaoxing, Zhejiang Province, 312300, China
| | - Wanli Duan
- Department of orthopedics, Shaoxing Shangyu People's Hospital, No. 517, Shimin Avenue, Baiguan Street, Shangyu District, Shaoxing, Zhejiang Province, 312300, China
| | - Jiang Zhu
- Department of orthopedics, Shaoxing Shangyu People's Hospital, No. 517, Shimin Avenue, Baiguan Street, Shangyu District, Shaoxing, Zhejiang Province, 312300, China
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Zheng Y, Zheng B, Meng X, Yan Y, He J, Liu Y. LncRNA DANCR promotes the proliferation, migration, and invasion of tongue squamous cell carcinoma cells through miR-135a-5p/KLF8 axis. Cancer Cell Int 2019; 19:302. [PMID: 31827393 PMCID: PMC6862788 DOI: 10.1186/s12935-019-1016-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/04/2019] [Indexed: 12/15/2022] Open
Abstract
Background Tongue squamous cell carcinoma (TSCC) is a most invasive cancer with high mortality and poor prognosis. It is reported that lncRNA DANCR has implications in multiple types of cancers. However, its biological role and underlying mechanism in TSCC progress are not well elucidated. Methods Our present study first investigated the function of DANCR on the proliferation, migration and invasion of TSCC cells by silencing or overexpressing DANCR. Further, the miR-135a-5p-Kruppel-like Factor 8 (KLF8) axis was focused on to explore the regulatory mechanism of DANCR on TSCC cell malignant phenotypes. Xenografted tumor growth using nude mice was performed to examine the role of DANCR in vivo. Results DANCR knockdown reduced the viability and inhibited the migration and invasion of TSCC cells in vitro, while ectopic expression of DANCR induced opposite effects. In vivo, the tumor growth and the expression of matrix metalloproteinase (MMP)-2/9 and KLF8 were also blocked by DANCR inhibition. In addition, we found that miR-135-5p directly targeted DANCR, which was negatively correlated with DANCR on TSCC progression. Its inhibition reversed the beneficial effects of DANCR silence on TSCC malignancies. Furthermore, the expression of KLF8 evidently altered by both DANCR and miR-135a-5p. Silencing KLF8 using its specific siRNA showed that KLF8 was responsible for the induction of miR-135a-5p inhibitor on TSCC cell malignancies and MMP-2/9 expression. Conclusions These findings, for the first time, suggest that DANCR plays an oncogenic role in TSCC progression via targeting miR-135a-5p/KLF8 axis, which provides a promising biomarker and treatment approach for preventing TSCC.
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Affiliation(s)
- Ying Zheng
- 1Department of Orthodontics, School of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, 110002 People's Republic of China
| | - Bowen Zheng
- 1Department of Orthodontics, School of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, 110002 People's Republic of China
| | - Xue Meng
- 2Department of Stomatology, Shengjing Hospital of China Medical University, Shenyang, 110004 People's Republic of China
| | - Yuwen Yan
- 1Department of Orthodontics, School of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, 110002 People's Republic of China
| | - Jia He
- 1Department of Orthodontics, School of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, 110002 People's Republic of China
| | - Yi Liu
- 1Department of Orthodontics, School of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, 110002 People's Republic of China
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Ma D, Liu H, Qin Y, Tian Z, Li S, Liang N. KLF8 overexpression promotes the growth of human lung cancer cells by promoting the expression of JMJD2A. Cancer Cell Int 2019; 19:258. [PMID: 31624471 PMCID: PMC6781403 DOI: 10.1186/s12935-019-0970-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 09/18/2019] [Indexed: 01/24/2023] Open
Abstract
Background Non-small-cell lung cancer (lung cancer) has become one of the leading causes worldwide and the underlying mechanism is not fully understood. The transcriptional factor Kruppel like factor 8 (KLF8) is involved in the initiation, progression, transformation, and metastasis of diverse cancers. However, the roles of KLF8 in human non-small cell lung cancer remain unknown. Methods CCK-8 kit and colony formation assay were performed to determine the cell growth of lung cancer cells. Flow cytometry analysis was used to evaluate apoptosis and cell cycle of lung cancer cells. Luciferase reporter assay was used to examine the activation of JMJD2A promoter by KLF8. Chromatin immunoprecipitation assay was performed to evaluate the binding of KLF8 to JMJD2A promoter. Western blot and polymerase chain reaction were applied to analyze the expression of interested genes. Results The mRNA and protein levels of KLF8 in human non-small cell lung cancer tissues were overexpressed compared with the non-cancer tissues. KLF8 was knocked down with lentivirus-mediated short-hairpin RNA (shRNA) in human lung cancer cells (A549 and H1299 cells). The phenotypic results showed that KLF8 knockdown decreased the proliferation rate and colony formation of lung cancer cells. By contrast, lentivirus-mediated KLF8 overexpression promoted the growth of lung cancer cells (A549 and H1299 cells) and non-cancerous bronchial epithelial cell line BEAS-2B. Next, we showed that KLF8 regulated cell cycle at the G0 phase but not regulates cellular apoptosis of lung cancer cells. KLF8 regulated the expression of the cell cycle regulators P21 and CDK4 in a JMJD2A-dependent manner and JMJD2A knockdown significantly blocked the functions of KLF8 in regulating cell cycle and proliferation of lung cancer cells. Finally, we observed that KLF8 bound the promoter of JMJD2A and facilitated the expression of JMJD2A. Conclusions Our evidence demonstrated that KLF8 upregulation in human lung cancer promotes the cell proliferation and colony formation of lung cancer cells. KLF8 binds to the promoter of JMJD2A and subsequently regulates the expression of P21 and CDK4, which contributes to the regulation of cell cycle by KLF8. KLF8 may serve as a target for the treatment of human lung cancer.
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Affiliation(s)
- Dongjie Ma
- Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730 China
| | - Hongsheng Liu
- Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730 China
| | - Yingzhi Qin
- Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730 China
| | - Zhenhuan Tian
- Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730 China
| | - Shanqing Li
- Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730 China
| | - Naixin Liang
- Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730 China
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Mukherjee D, Lu H, Yu L, He C, Lahiri SK, Li T, Zhao J. Krüppel-like factor 8 activates the transcription of C-X-C cytokine receptor type 4 to promote breast cancer cell invasion, transendothelial migration and metastasis. Oncotarget 2018; 7:23552-68. [PMID: 26993780 PMCID: PMC5029647 DOI: 10.18632/oncotarget.8083] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 02/25/2016] [Indexed: 02/04/2023] Open
Abstract
Krüppel-like factor 8 (KLF8) has been strongly implicated in breast cancer metastasis. However, the underlying mechanisms remain largely unknown. Here we report a novel signaling from KLF8 to C-X-C cytokine receptor type 4 (CXCR4) in breast cancer. Overexpression of KLF8 in MCF-10A cells induced CXCR4 expression at both mRNA and protein levels, as determined by quantitative real-time PCR and immunoblotting. This induction was well correlated with increased Boyden chamber migration, matrigel invasion and transendothelial migration (TEM) of the cells towards the ligand CXCL12. On the other hand, knockdown of KLF8 in MDA-MB-231 cells reduced CXCR4 expression associated with decreased cell migration, invasion and TEM towards CXCL12. Histological and database mining analyses of independent cohorts of patient tissue microarrays revealed a correlation of aberrant co-elevation of KLF8 and CXCR4 with metastatic potential. Promoter analysis indicated that KLF8 directly binds and activates the human CXCR4 gene promoter. Interestingly, a CXCR4-dependent activation of focal adhesion kinase (FAK), a known upregulator of KLF8, was highly induced by CXCL12 treatment in KLF8-overexpressing, but not KLF8 deficient cells. This activation of FAK in turn induced a further increase in KLF8 expression. Xenograft studies showed that overexpression of CXCR4, but not a dominant-negative mutant of it, in the MDA-MB-231 cells prevented the invasive growth of primary tumor and lung metastasis from inhibition by knockdown of KLF8. These results collectively suggest a critical role for a previously unidentified feed-forward signaling wheel made of KLF8, CXCR4 and FAK in promoting breast cancer metastasis and shed new light on potentially more effective anti-cancer strategies.
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Affiliation(s)
- Debarati Mukherjee
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Heng Lu
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Lin Yu
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Chunjiang He
- School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Satadru K Lahiri
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Tianshu Li
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA.,Current address: Cleveland Clinic, Cleveland, OH, USA
| | - Jihe Zhao
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
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12
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Krüppel-Like Factor 8 Overexpression Correlates with Poor Prognosis in Non-Small Cell Lung Cancer. Pathol Oncol Res 2017; 25:115-121. [DOI: 10.1007/s12253-017-0321-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 09/21/2017] [Indexed: 02/07/2023]
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13
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Bian T, Jiang D, Liu J, Yuan X, Feng J, Li Q, Zhang Q, Li X, Liu Y, Zhang J. miR-1236-3p suppresses the migration and invasion by targeting KLF8 in lung adenocarcinoma A549 cells. Biochem Biophys Res Commun 2017; 492:461-467. [DOI: 10.1016/j.bbrc.2017.08.074] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 08/20/2017] [Indexed: 12/25/2022]
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14
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Bialkowska AB, Yang VW, Mallipattu SK. Krüppel-like factors in mammalian stem cells and development. Development 2017; 144:737-754. [PMID: 28246209 DOI: 10.1242/dev.145441] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Krüppel-like factors (KLFs) are a family of zinc-finger transcription factors that are found in many species. Recent studies have shown that KLFs play a fundamental role in regulating diverse biological processes such as cell proliferation, differentiation, development and regeneration. Of note, several KLFs are also crucial for maintaining pluripotency and, hence, have been linked to reprogramming and regenerative medicine approaches. Here, we review the crucial functions of KLFs in mammalian embryogenesis, stem cell biology and regeneration, as revealed by studies of animal models. We also highlight how KLFs have been implicated in human diseases and outline potential avenues for future research.
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Affiliation(s)
- Agnieszka B Bialkowska
- Division of Gastroenterology, Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA
| | - Vincent W Yang
- Division of Gastroenterology, Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA.,Department of Physiology and Biophysics, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA
| | - Sandeep K Mallipattu
- Division of Nephrology, Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA
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15
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Liu Y, Yao X, Zhang Q, Qian L, Feng J, Bian T, Zhang J, Tian Y. Expression of Kruppel-like factor 8 and Ki67 in lung adenocarcinoma and prognosis. Exp Ther Med 2017; 14:1351-1356. [PMID: 28810596 PMCID: PMC5526062 DOI: 10.3892/etm.2017.4632] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 04/07/2017] [Indexed: 01/23/2023] Open
Abstract
Kruppel-like factor 8 (KLF8) belongs to the KLF family and has various roles in the regulation of the cell cycle, proliferation and tumor genesis. KLF8 is overexpressed in gastric, ovarian, breast and renal cancer. Additionally, KLF8 may affect invasion and metastasis of tumors. However, whether KLF8 also acts as an ontogeny in lung adenocarcinoma (LAC) remains unknown. The aim of the present study was to determine the association between KLF8 expression and various clinical and pathological parameters. Western blot assays and immune histochemistry analyses revealed that KLF8 level in LAC tissues was higher than that in the normal lung tissues and KLF8 expression was significantly associated with clinical variables (P<0.05). Kaplan-Meier curves revealed that high expression of KLF8 was related to poor prognosis in patients with LAC. The present study also demonstrated that KLF8 was involved in the progression of lung adenocarcinoma. This data suggested that KLF8 may act as a prognostic factor in lung adenocarcinoma progression.
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Affiliation(s)
- Yifei Liu
- Department of Radiotherapy and Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215000, P.R. China.,Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Xiufang Yao
- Department of Pathology, The First People's Hospital of Rudong, Nantong, Jiangsu 226401, P.R. China
| | - Qing Zhang
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Li Qian
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Jia Feng
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Tingting Bian
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Jianguo Zhang
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Ye Tian
- Department of Radiotherapy and Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215000, P.R. China
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16
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Wang L, Brooks AN, Fan J, Wan Y, Gambe R, Li S, Hergert S, Yin S, Freeman SS, Levin JZ, Fan L, Seiler M, Buonamici S, Smith PG, Chau KF, Cibulskis CL, Zhang W, Rassenti LZ, Ghia EM, Kipps TJ, Fernandes S, Bloch DB, Kotliar D, Landau DA, Shukla SA, Aster JC, Reed R, DeLuca DS, Brown JR, Neuberg D, Getz G, Livak KJ, Meyerson MM, Kharchenko PV, Wu CJ. Transcriptomic Characterization of SF3B1 Mutation Reveals Its Pleiotropic Effects in Chronic Lymphocytic Leukemia. Cancer Cell 2016; 30:750-763. [PMID: 27818134 PMCID: PMC5127278 DOI: 10.1016/j.ccell.2016.10.005] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 09/01/2016] [Accepted: 10/04/2016] [Indexed: 12/16/2022]
Abstract
Mutations in SF3B1, which encodes a spliceosome component, are associated with poor outcome in chronic lymphocytic leukemia (CLL), but how these contribute to CLL progression remains poorly understood. We undertook a transcriptomic characterization of primary human CLL cells to identify transcripts and pathways affected by SF3B1 mutation. Splicing alterations, identified in the analysis of bulk cells, were confirmed in single SF3B1-mutated CLL cells and also found in cell lines ectopically expressing mutant SF3B1. SF3B1 mutation was found to dysregulate multiple cellular functions including DNA damage response, telomere maintenance, and Notch signaling (mediated through KLF8 upregulation, increased TERC and TERT expression, or altered splicing of DVL2 transcript, respectively). SF3B1 mutation leads to diverse changes in CLL-related pathways.
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Affiliation(s)
- Lili Wang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Angela N Brooks
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA; University of California, Santa Cruz, CA 95064, USA
| | - Jean Fan
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Youzhong Wan
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; National Engineering Laboratory of AIDS Vaccine, School of Life Science, Jilin University, Changchun, Jilin, PRC
| | - Rutendo Gambe
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Shuqiang Li
- Fluidigm Corporation, South San Francisco, CA 94080, USA
| | - Sarah Hergert
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Shanye Yin
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | | | - Joshua Z Levin
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | - Lin Fan
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | | | | | | | | | | | - Wandi Zhang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Laura Z Rassenti
- Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Emanuela M Ghia
- Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Thomas J Kipps
- Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stacey Fernandes
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Donald B Bloch
- Center for Immunology and Inflammatory Disease, Massachusetts General Hospital, Boston, MA 02115, USA
| | | | - Dan A Landau
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Sachet A Shukla
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Jon C Aster
- Department of Pathology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Robin Reed
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - David S DeLuca
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | - Jennifer R Brown
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Donna Neuberg
- Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Gad Getz
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | | | - Matthew M Meyerson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Catherine J Wu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA.
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17
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Chu LF, Leng N, Zhang J, Hou Z, Mamott D, Vereide DT, Choi J, Kendziorski C, Stewart R, Thomson JA. Single-cell RNA-seq reveals novel regulators of human embryonic stem cell differentiation to definitive endoderm. Genome Biol 2016; 17:173. [PMID: 27534536 PMCID: PMC4989499 DOI: 10.1186/s13059-016-1033-x] [Citation(s) in RCA: 249] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Accepted: 07/27/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Human pluripotent stem cells offer the best available model to study the underlying cellular and molecular mechanisms of human embryonic lineage specification. However, it is not fully understood how individual stem cells exit the pluripotent state and transition towards their respective progenitor states. RESULTS Here, we analyze the transcriptomes of human embryonic stem cell-derived lineage-specific progenitors by single-cell RNA-sequencing (scRNA-seq). We identify a definitive endoderm (DE) transcriptomic signature that leads us to pinpoint a critical time window when DE differentiation is enhanced by hypoxia. The molecular mechanisms governing the emergence of DE are further examined by time course scRNA-seq experiments, employing two new statistical tools to identify stage-specific genes over time (SCPattern) and to reconstruct the differentiation trajectory from the pluripotent state through mesendoderm to DE (Wave-Crest). Importantly, presumptive DE cells can be detected during the transitory phase from Brachyury (T) (+) mesendoderm toward a CXCR4 (+) DE state. Novel regulators are identified within this time window and are functionally validated on a screening platform with a T-2A-EGFP knock-in reporter engineered by CRISPR/Cas9. Through loss-of-function and gain-of-function experiments, we demonstrate that KLF8 plays a pivotal role modulating mesendoderm to DE differentiation. CONCLUSIONS We report the analysis of 1776 cells by scRNA-seq covering distinct human embryonic stem cell-derived progenitor states. By reconstructing a differentiation trajectory at single-cell resolution, novel regulators of the mesendoderm transition to DE are elucidated and validated. Our strategy of combining single-cell analysis and genetic approaches can be applied to uncover novel regulators governing cell fate decisions in a variety of systems.
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Affiliation(s)
- Li-Fang Chu
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA.
| | - Ning Leng
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA.,Present address: Genentech, Inc., South San Francisco, CA, USA
| | - Jue Zhang
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA
| | - Zhonggang Hou
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA.,Present address: Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Daniel Mamott
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA
| | - David T Vereide
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA
| | - Jeea Choi
- Department of Statistics, University of Wisconsin, Madison, WI, USA
| | - Christina Kendziorski
- Department of Biostatistics and Medical Informatics, University of Wisconsin, Madison, WI, USA
| | - Ron Stewart
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA
| | - James A Thomson
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53715, USA. .,Department of Cell & Regenerative Biology, University of Wisconsin-Madison, Madison, WI, USA. .,Department of Molecular, Cellular, & Developmental Biology, University of California, Santa Barbara, CA, USA.
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18
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Shen YN, He HG, Shi Y, Cao J, Yuan JY, Wang ZC, Shi CF, Zhu N, Wei YP, Liu F, Huang JL, Yang GS, Lu JH. Krüppel-like factor 8 promotes cancer stem cell-like traits in hepatocellular carcinoma through Wnt/β-catenin signaling. Mol Carcinog 2016; 56:751-760. [PMID: 27478926 DOI: 10.1002/mc.22532] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 07/25/2016] [Accepted: 07/29/2016] [Indexed: 01/15/2023]
Abstract
Krüppel-like factor 8 (KLF8) is highly expressed in hepatocellular carcinoma (HCC) and contributes to tumor initiation and progression by promoting HCC cell proliferation and invasion. However, the role of KLF8 in liver cancer stem cells (LCSCs) is not known. In the current study, we investigated the role of KLF8 in LCSCs to determine if KLF8 is a novel marker of these cells. We found that KLF8 was highly expressed in primary HCC tumors, distant migrated tissues, and LCSCs. Patients with high KLF8 expression had a poor prognosis. KLF8 promoted stem cell-like features through activation of the Wnt/β-catenin signaling pathway. Cell apoptosis was significantly increased in HCC cells with knockdown of KLF8 compared with the control cells when treated with the same doses of sorafenib or cisplatin. Taken together, our study shows that KLF8 plays a potent oncogenic role in HCC tumorigenesis by maintaining stem cell-like features through activation of the Wnt/β-catenin signaling pathway and promoting chemoresistance. Thus, targeting KLF8 may provide an effective therapeutic approach to suppress tumorigenicity of HCC. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Yi-Nan Shen
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China.,Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hai-Guan He
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Yang Shi
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Jian Cao
- The 3rd Department of Surgery, The Third People's Hospital of Jiujiang, Jiujiang, Jiangxi Prov, China
| | - Jian-Yong Yuan
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Zhou-Chong Wang
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Chun-Feng Shi
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Nan Zhu
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Yong-Peng Wei
- Xiangan Institute of Health of Retired Cadres, Second Military Medical University, Shanghai, China
| | - Fang Liu
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Jia-Li Huang
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Guang-Shun Yang
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Jun-Hua Lu
- The 5th Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
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19
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Yi X, Li Y, Zai H, Long X, Li W. KLF8 knockdown triggered growth inhibition and induced cell phase arrest in human pancreatic cancer cells. Gene 2016; 585:22-27. [DOI: 10.1016/j.gene.2016.03.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 03/08/2016] [Accepted: 03/12/2016] [Indexed: 02/07/2023]
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20
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Identification of epidermal growth factor receptor and its inhibitory microRNA141 as novel targets of Krüppel-like factor 8 in breast cancer. Oncotarget 2016; 6:21428-42. [PMID: 26025929 PMCID: PMC4673276 DOI: 10.18632/oncotarget.4077] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 05/14/2015] [Indexed: 01/22/2023] Open
Abstract
Krüppel-like factor 8 (KLF8) is a dual transcriptional factor critical for breast cancer progression. Epidermal growth factor receptor (EGFR) is frequently overexpressed in aggressive such as triple-negative breast cancer and associated with poor clinical outcomes. Here we report a novel KLF8-EGFR signaling axis in breast cancer. We identified a highly correlated co-overexpression between KLF8 and EGFR in invasive breast cancer cells and patient tumor samples. Overexpression of KLF8 in the non-tumorigenic MCF-10A cells induced the expression of EGFR, whereas knockdown of KLF8 from the MDA-MB-231 cells decreased it. Promoter activation and binding assays indicated that KLF8 promotes the EGFR expression by directly binding its gene promoter. We also revealed that KLF8 directly represses the promoter of miR141 and miR141 targets the 3′-untranslational region of EGFR transcript to inhibit EGFR translation. Treatment with the EGFR inhibitor AG1478 or overexpression of miR141 blocked the activity of ERK downstream of EGFR and inhibited KLF8-depndent cell invasiveness, proliferation and viability in cell culture and invasive growth and lung metastasis in nude mice. Conversely, overexpression of an inhibitory sponge of miR141 led to the opposite phenotypes. Taken together, these findings demonstrate a novel KLF8 to miR141/EGFR signaling pathway potentially crucial for breast cancer malignancy.
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21
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Wang X, Wong J, Sevinsky CJ, Kokabee L, Khan F, Sun Y, Conklin DS. Bruton's Tyrosine Kinase Inhibitors Prevent Therapeutic Escape in Breast Cancer Cells. Mol Cancer Ther 2016; 15:2198-208. [PMID: 27256378 DOI: 10.1158/1535-7163.mct-15-0813] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 05/19/2016] [Indexed: 01/10/2023]
Abstract
We have reported that a novel isoform of BTK (BTK-C) expressed in breast cancer protects these cells from apoptosis. In this study, we show that recently developed inhibitors of BTK, such as ibrutinib (PCI-32765), AVL-292, and CGI-1746, reduce breast cancer cell survival and prevent drug-resistant clones from arising. Ibrutinib treatment impacts HER2(+) breast cancer cell viability at lower concentrations than the established breast cancer therapeutic lapatinib. In addition to inhibiting BTK, ibrutinib, but not AVL-292 and CGI-1746, efficiently blocks the activation of EGFR, HER2, ErbB3, and ErbB4. Consequently, the activation of AKT and ERK signaling pathways are also blocked leading to a G1-S cell-cycle delay and increased apoptosis. Importantly, inhibition of BTK prevents activation of the AKT signaling pathway by NRG or EGF that has been shown to promote growth factor-driven lapatinib resistance in HER2(+) breast cancer cells. HER2(+) breast cancer cell proliferation is blocked by ibrutinib even in the presence of these factors. AVL-292, which has no effect on EGFR family activation, prevents NRG- and EGF-dependent growth factor-driven resistance to lapatinib in HER2(+) breast cancer cells. In vivo, ibrutinib inhibits HER2(+) xenograft tumor growth. Consistent with this, immunofluorescence analysis of xenograft tumors shows that ibrutinib reduces the phosphorylation of HER2, BTK, Akt, and Erk and histone H3 and increases cleaved caspase-3 signals. As BTK-C and HER2 are often coexpressed in human breast cancers, these observations indicate that BTK-C is a potential therapeutic target and that ibrutinib could be an effective drug especially for HER2(+) breast cancer. Mol Cancer Ther; 15(9); 2198-208. ©2016 AACR.
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Affiliation(s)
- Xianhui Wang
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York
| | - Jason Wong
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York
| | - Christopher J Sevinsky
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York
| | - Leila Kokabee
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York. Department of Molecular Medicine, Pasteur Institute of Iran, Tehran, Iran
| | - Faiza Khan
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York
| | - Yan Sun
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York
| | - Douglas S Conklin
- Cancer Research Center and Department of Biomedical Sciences, State University of New York, University at Albany, Rensselaer, New York.
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22
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Ding B, Liu P, Liu W, Sun P, Wang CL. Emerging roles of Krüppel-like factor 4 in cancer and cancer stem cells. Asian Pac J Cancer Prev 2016; 16:3629-33. [PMID: 25987013 DOI: 10.7314/apjcp.2015.16.9.3629] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Cancer stem cells (CSCs) are rare subpopulations within tumors which are recognized as culprits in cancer recurrence, drug resistance and metastasis. However, the molecular mechanisms of how CSCs are regulated remain elusive. Kruppel-like factors (KLFs) are evolutionarily conserved zinc finger-containing transcription factors with diverse functions in cell differentiation, proliferation, embryogenesis and pluripotency. Recent progress has highlighted the significance of KLFs, especially KLF4, in cancer and CSCs. Therefore, for better therapeutics of cancer disease, it is crucial to develop a deeper understanding of the mechanisms of how KLF4 regulate CSC functions. Herein we summarized the current understanding of the transcriptional regulation of KLF4 in CSCs, and discussed the functional implications of targeting CSCs for potential cancer therapeutics.
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Affiliation(s)
- Bo Ding
- Department of Orthodontics, School of Stomatology, Shandong University, China E-mail :
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23
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Zhou D, Zhang YI, Liang D, Yuan Y, Zeng D, Chen J, Yang J. Effect of combination therapy of siRNA targeting growth hormone receptor and 5-fluorouracil in hepatic metastasis of colon cancer. Oncol Lett 2015; 10:3505-3509. [PMID: 26788158 PMCID: PMC4665694 DOI: 10.3892/ol.2015.3770] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 09/30/2015] [Indexed: 12/28/2022] Open
Abstract
The aim of this study was to investigate the effects of small interfering RNA (siRNA) targeting human growth hormone receptor (hGHR) combined with 5-fluorouracil (5-FU) on the hepatic metastasis of colon cancer. The animal model of liver metastases using human SW480 colon cancer cells was established on BALB/c mice and the siRNA interfering plasmid targeting hGHR gene was constructed. The tumor-bearing mice were randomly divided into the saline control, plasmid, growth hormone (GH), 5-FU, 5-FU+plasmid and 5-FU+plasmid+GH groups. The liver metastasis in each group was observed. All the animals showed liver metastases and using siRNA-interfering plasmid treatment the incidence of liver metastases was significantly reduced in the tumor groups compared to the saline or GH group. The combined treatment of interfering plasmid and 5-FU slightly decreased the incidence of liver metastases in the tumor groups compared to the plasmid alone or 5-FU alone treatment, although the findings were not statistically significant. On the basis of the combination of interfering plasmid and 5-FU, the additional GH did not increase the incidence of liver metastases (P>0.05), but improved the weight loss of the mice (P<0.05) induced by the inhibition of GHR and toxicity of 5-FU. The present results showed that siRNA targeting hGHR is able to reduce the incidence of liver metastases of human SW480 colon cancer cells in mice. Thus, GHR may be important in tumor metastasis.
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Affiliation(s)
- Dong Zhou
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Y I Zhang
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Daoming Liang
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Yong Yuan
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Demiao Zeng
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Jiayong Chen
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Jie Yang
- Department of General Surgery, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
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24
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Liang K, Liu T, Chu N, Kang J, Zhang R, Yu Y, Li D, Lu D. KLF8 is required for bladder cancer cell proliferation and migration. Biotechnol Appl Biochem 2015; 62:628-33. [PMID: 25323066 DOI: 10.1002/bab.1310] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Accepted: 10/13/2014] [Indexed: 12/31/2022]
Abstract
Krüppel-like factor 8 (KLF8) belongs to the Sp/KLF family of transcription factors. Recently, it is affirmed that KLF8 plays an important role in the regulation of epithelial-mesenchymal transition, which is a key process that occurs during cancer metastasis. Although the overexpression of KLF8 has been observed in several types of human cancers, the functional role of KLF8 in human bladder cancer remains unknown. Here, we investigated the effects of KLF8 knockdown on bladder cancer cell proliferation and migration in vitro. Lentivirus-mediated small interfering RNA (siRNA) targeting KLF8 specifically downregulated its expression in T24 and BT5637 bladder cancer cells. Knockdown of KLF8 significantly inhibit cell proliferation and colony formation. Cell cycle analysis showed that knockdown of KLF8 arrested T24 cells in the G0/G1 phase. Moreover, cell migration was attenuated in T24 cells after KLF8 knockdown. Furthermore, knockdown of KLF8 resulted in a reduction in vimentin and N-cadherin expression and an increase in β-catenin expression. These results indicate that KLF8 plays a crucial role in proliferation and migration of bladder cancer cells, and inhibition of KLF8 by siRNA may provide a potential therapeutic approach for gene therapy in bladder cancer.
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Affiliation(s)
- Kai Liang
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
| | - Tao Liu
- Department of Urology, the First Affiliated Hospital, China Medical University, Shenyang, People's Republic of China
| | - Ning Chu
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
| | - Jian Kang
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
| | - Rui Zhang
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
| | - Yong Yu
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
| | - Dongqi Li
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
| | - Dexiang Lu
- Department of Urology, Hospital of Heilongjiang Province, Harbin, People's Republic of China
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MiR-135a inhibits migration and invasion and regulates EMT-related marker genes by targeting KLF8 in lung cancer cells. Biochem Biophys Res Commun 2015; 465:125-30. [PMID: 26235874 DOI: 10.1016/j.bbrc.2015.07.145] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 07/23/2015] [Indexed: 02/04/2023]
Abstract
Epithelial-mesenchymal transition (EMT) has been shown to be related to the pathogenesis of various diseases. Recently, microRNAs (miRNA) have been recognized as a new class of genes involved in human tumorigenesis. In this study, we found that the expression levels of miR-135a were dramatically decreased in NSCLC cell lines and clinical NSCLC tissue samples. Then, we demonstrated that miR-135a significantly suppressed the migration and invasion of lung cancer cells in vitro, suggesting that miR-135a may be a novel tumor suppressor. Further studies revealed that the transcription factor KLF8 was a target gene of miR-135a in NSCLC cells, as miR-135a bound directly to the 3'-untranslated region (3'-UTR) of KLF8, thus reducing both the expression of KLF8 at the mRNA and protein levels. In addition, the EMT marker E-cadherin or vimentin was also down-regulated or up-regulated on miR-135a treatment. Moreover, silencing KLF8 was able to inhibit the migration and invasion of lung cancer cells. In conclusion, these findings indicate that miR-135a suppresses the migration and invasion of NSCLC cells through targeting KLF8, which is involved in the EMT process. This finding provides new insight into the mechanism of NSCLC progression.
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26
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Dobrivojević M, Habek N, Kapuralin K, Ćurlin M, Gajović S. Krüppel-like transcription factor 8 (Klf8) is expressed and active in the neurons of the mouse brain. Gene 2015; 570:132-40. [PMID: 26071188 DOI: 10.1016/j.gene.2015.06.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 05/27/2015] [Accepted: 06/04/2015] [Indexed: 10/23/2022]
Abstract
Krüppel-like transcription factor 8 (KLF8) is a transcription factor suggested to be involved in various cellular events, including malignant cell transformation, still its expression in the adult rodent brain remained unknown. To analyze Klf8 in the mouse brain and to identify cell types expressing it, a specific transgenic Klf8(Gt1Gaj) mouse was used. The resulting Klf8 gene-driven β-galactosidase activity was visualized by X-gal histochemical staining of the brain sections. The obtained results were complemented by in situ RNA hybridization and immunohistochemistry. Klf8 was highly expressed throughout the adult mouse brain gray matter including the cerebral cortex, hippocampus, olfactory bulb, hypothalamus, pallidum, and striatum, but not in the cerebellum. Immunofluorescent double-labeling revealed that KLF8-immunoreactive cells were neurons, and the staining was located in their nucleus. This was the first study showing that Klf8 was highly expressed in various regions of the mouse brain and in particular in the neurons, where it was localized in the cell nuclei.
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Affiliation(s)
- Marina Dobrivojević
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Nikola Habek
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Katarina Kapuralin
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Marija Ćurlin
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Srećko Gajović
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia.
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Loesch K, Galaviz S, Hamoui Z, Clanton R, Akabani G, Deveau M, DeJesus M, Ioerger T, Sacchettini JC, Wallis D. Functional genomics screening utilizing mutant mouse embryonic stem cells identifies novel radiation-response genes. PLoS One 2015; 10:e0120534. [PMID: 25853515 PMCID: PMC4390347 DOI: 10.1371/journal.pone.0120534] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/23/2015] [Indexed: 02/07/2023] Open
Abstract
Elucidating the genetic determinants of radiation response is crucial to optimizing and individualizing radiotherapy for cancer patients. In order to identify genes that are involved in enhanced sensitivity or resistance to radiation, a library of stable mutant murine embryonic stem cells (ESCs), each with a defined mutation, was screened for cell viability and gene expression in response to radiation exposure. We focused on a cancer-relevant subset of over 500 mutant ESC lines. We identified 13 genes; 7 genes that have been previously implicated in radiation response and 6 other genes that have never been implicated in radiation response. After screening, proteomic analysis showed enrichment for genes involved in cellular component disassembly (e.g. Dstn and Pex14) and regulation of growth (e.g. Adnp2, Epc1, and Ing4). Overall, the best targets with the highest potential for sensitizing cancer cells to radiation were Dstn and Map2k6, and the best targets for enhancing resistance to radiation were Iqgap and Vcan. Hence, we provide compelling evidence that screening mutant ESCs is a powerful approach to identify genes that alter radiation response. Ultimately, this knowledge can be used to define genetic variants or therapeutic targets that will enhance clinical therapy.
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Affiliation(s)
- Kimberly Loesch
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Stacy Galaviz
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Zaher Hamoui
- Department of Nuclear Engineering, Texas A&M University, College Station, Texas, United States of America
| | - Ryan Clanton
- Department of Nuclear Engineering, Texas A&M University, College Station, Texas, United States of America
| | - Gamal Akabani
- Department of Nuclear Engineering, Texas A&M University, College Station, Texas, United States of America
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
- Texas A&M Institute for Preclinical Studies, Texas A&M University, College Station, Texas, United States of America
| | - Michael Deveau
- Department of Small Animal Clinical Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Michael DeJesus
- Department of Computer Science and Engineering, Texas A&M University, College Station, Texas, United States of America
| | - Thomas Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, Texas, United States of America
| | - James C. Sacchettini
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Deeann Wallis
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
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Human cancer: Is it linked to dysfunctional lipid metabolism? Biochim Biophys Acta Gen Subj 2015; 1850:352-64. [DOI: 10.1016/j.bbagen.2014.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 10/27/2014] [Accepted: 11/03/2014] [Indexed: 11/23/2022]
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Liu N, Wang Y, Zhou Y, Pang H, Zhou J, Qian P, Liu L, Zhang H. Krüppel-like factor 8 involved in hypoxia promotes the invasion and metastasis of gastric cancer via epithelial to mesenchymal transition. Oncol Rep 2014; 32:2397-404. [PMID: 25333643 DOI: 10.3892/or.2014.3495] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 07/17/2014] [Indexed: 11/05/2022] Open
Abstract
Previously, we reported that hypoxia was able to induce invasion and metastasis in gastric cancer and that hypoxia-inducible factor-1 (HIF-1) is a key factor involved in this tumor type. Krüppel-like factor 8 (KLF8) as a transcriptional repressor has been suggested as a promoter of tumor metastasis in breast cancer and an inducer of the epithelial‑mesenchymal transition (EMT). KLF8 is also highly expressed in gastric cancer tissues, contributing to poor prognosis. However, the association between KLF8 and HIF-1 in regulating the progression of human gastric cancer in hypoxia is unclear. In the present study, we found that KLF8 was overexpressed in gastric cancer metastatic tissues and cells. Additionally, KLF8 siRNA significantly inhibited SGC7901 cell invasion and migration compared with SGC7901, SGC7901/Scr-si cells. Hypoxia is thus able to induce KLF8 expression and EMT in SGC7901 cells. However, following the examination of changes in cell morphology and epithelial and mesenchymal markers, it was found that KLF8 siRNA and HIF-1 siRNA strongly reversed EMT in cells undergoing hypoxia. Furthermore, hypoxia-induced KLF8 overexpression was attenuated by HIF-1 siRNA. Experiments using luciferase promoter constructs resulted in a marked increase in the activity of cells exposed to hypoxia and decreased activity in cells co-transfected with HIF-1 siRNA. The chromatin immunoprecipitation assay revealed proximal HRE at -133 is the main HIF-1 binding site in the KLF8 promoter. In conclusion, the results demonstrated that KLF8 is actively enhanced by hypoxia and is a novel HIF-1 target. KLF8 is a novel EMT regulating transcription factor that involved in the progression of gastric cancer. The specific anti-EMT drugs in combination with anti-hypoxia are new promising cancer therapies.
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Affiliation(s)
- Na Liu
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Yafang Wang
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Yongan Zhou
- Department of Thoracic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Hailin Pang
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Jing Zhou
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Pei Qian
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Lili Liu
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Helong Zhang
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
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Zhang QH, Dou HT, Tang YJ, Su S, Liu PS. Lentivirus-mediated knockdown of Krüppel-like factor 9 inhibits the growth of ovarian cancer. Arch Gynecol Obstet 2014; 291:377-82. [PMID: 25216959 DOI: 10.1007/s00404-014-3405-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 07/30/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE Ovarian cancer is among the top diseases in the list of malignant gynaecologic tumors. In the present study, we aim to investigate the effect of lentivirus-mediated knockdown of Krüppel-like factor 9 (KLF9) on cell viability and tumor growth in ovarian cancer. METHODS Firstly, the expression of KLF9 was determined by real-time PCR and western blot in human ovarian cancer tissues. Then, endogenous KLF9 expression was silenced by lentivirus in SKOV3 and OVCAR3 ovarian cancer cells, and followed by MTT and BrdU incorporation assays, cell cycle analysis and tumor xenografts in nude mice. RESULTS Our results found that the expression of KLF9 is up-regulated in human ovarian cancer. As expected, KLF9 knockdown significantly inhibited cell proliferation and resulted in cell cycle arrest in the G0/G1 phase. Besides, KLF9 deficiency significantly inhibited tumor growth in nude mice. CONCLUSION Therefore, our data reveal that lentivirus-mediated KLF9 silencing might be promising in the treatment of human ovarian cancer.
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Affiliation(s)
- Qing-hua Zhang
- Department of Gynaecology, Central Hospital of Zibo, Zibo, 255000, Shandong, China
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31
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Lin F, Shen Z, Tang LN, Zheng SE, Sun YJ, Min DL, Yao Y. KLF8 knockdown suppresses proliferation and invasion in human osteosarcoma cells. Mol Med Rep 2014; 9:1613-7. [PMID: 24604387 PMCID: PMC4020472 DOI: 10.3892/mmr.2014.2027] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 02/13/2014] [Indexed: 01/24/2023] Open
Abstract
Krüppel-like factor 8 (KLF8) is a transcription factor that is important in the regulation of the cell cycle and has a critical role in oncogenic transformation and epithelial to mesenchymal transition (EMT). EMT is a key process in tumor metastasis. Although overexpression of KLF8 has been observed in a variety of human tumor types, the role of KLF8 in human osteosarcoma is yet to be elucidated. The present study aimed to investigate the biological impact of KLF8 on Saos-2 osteosarcoma cells. KLF8 gene expression was knocked down in vitro using a lentivirus-mediated small interfering (si)RNA method. Cell proliferation and cell cycle distribution were evaluated using 3-(4,5)-dimethylthiahiazo(-z-yl)-3,5-di-phenytetrazoliumromide and colony formation assays, and flow cytometry, respectively. Cell invasion was analyzed using a Transwell® invasion assay. Knockdown of KLF8 was found to significantly inhibit proliferation and invasion in osteosarcoma cells. These data suggest that KLF8 may exhibit an important role in osteosarcoma tumorigenesis and that KLF8 may be a potential therapeutic target for the treatment of osteosarcoma.
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Affiliation(s)
- Feng Lin
- Graduate School of Medicine, Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Zan Shen
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Li-Na Tang
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Shui-Er Zheng
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Yuan-Jue Sun
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Da-Liu Min
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Yang Yao
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
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32
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Zhao J. KLF8: so different in ovarian and breast cancer. Oncoscience 2014; 1:248-249. [PMID: 25485290 PMCID: PMC4256715 DOI: 10.18632/oncoscience.34] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 04/28/2014] [Indexed: 11/25/2022] Open
Affiliation(s)
- Jihe Zhao
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
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33
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Hsu LS, Wu PR, Yeh KT, Yeh CM, Shen KH, Chen CJ, Soon MS. Positive nuclear expression of KLF8 might be correlated with shorter survival in gastric adenocarcinoma. Ann Diagn Pathol 2013; 18:74-7. [PMID: 24461703 DOI: 10.1016/j.anndiagpath.2013.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 12/13/2013] [Indexed: 12/28/2022]
Abstract
Krűppel-like factor 8 (KLF8) is important in cell proliferation, epithelial-to-mesenchymal transition, cell migration, and invasion. Gastric adenocarcinoma is among the leading causes of cancer-related death in the world. In this study, the clinicopathologic correlation of KLF8 expression with gastric adenocarcinoma in Taiwan was investigated. The nuclear localization of KLF8 was correlated with advanced stage (P = .008) and 3-year survival rate (P = .043). The nuclear expression of KLF8 was significantly higher in the diffused type of gastric adenocarcinoma compared with the intestinal type (P = .036). Kaplan-Meier analysis results showed that patients with positive nuclear KLF8 had significantly lower overall survival rate compared with those with negative nuclear KLF8 (P = .011). Univariate analysis results indicated that positive nuclear KLF8 expression, advanced stage, and lymph node metastasis are correlated with lower overall survival. Positive nuclear KLF8 might be correlated with lower survival in gastric adenocarcinoma patients and might be an oncogene property in gastric adenocarcinoma carcinogenesis.
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Affiliation(s)
- Li-Sung Hsu
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan; Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Pei-Ru Wu
- Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan
| | - Ken-Tu Yeh
- Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan; School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Chung-Min Yeh
- Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan
| | - Ko-Hung Shen
- Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan
| | - Chih-Jun Chen
- Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan; Department of Medical Technology, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, Taiwan; School of Medicine, Chung Shan Medical University, Taichung, Taiwan.
| | - Maw-Soan Soon
- Department of Gastroenterology, Changhua Christian Hospital, Changhua, Taiwan.
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34
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Krüppel-like factor 8 ameliorates Alzheimer's disease by activating β-catenin. J Mol Neurosci 2013; 52:231-41. [PMID: 24114572 DOI: 10.1007/s12031-013-0131-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 09/20/2013] [Indexed: 12/20/2022]
Abstract
A sustained loss of Wnt signaling function may be involved in the pathology of Alzheimer's disease (AD). Krüppel-like factor 8 (KLF8) induces the activation of Wnt/β-catenin signaling pathway. Thus, KLF8 may be related with the risk of AD. We want to know the role of KLF8 in the development of AD. A rat brain slice model for AD was established. Quantitative RT-PCR, western blotting, and fluorescence staining assays were carried out to examine the effects of KLF8 on the protein expression of some important molecules, which are associated with the development of AD. The enhanced expression level of KLF8 could increase the protein expression level of β-catenin, which interacted with and inhibited nuclear factor-kappa B (NF-κB). The protein levels of KLF8 and β-catenin were increased, while the level of NF-κB was decreased in the AD model. The inhibition of NF-κB was followed by the decrease of the protein expression levels of amyloid precursor protein (APP) and phosphorylated tau (Phospho-Tau). The protein level of KLF8 was decreasing from stages I to IV in patients with AD. This study provides evidence that KLF8 can inhibit the progression of AD.
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35
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Li T, Lu H, Shen C, Lahiri SK, Wason MS, Mukherjee D, Yu L, Zhao J. Identification of epithelial stromal interaction 1 as a novel effector downstream of Krüppel-like factor 8 in breast cancer invasion and metastasis. Oncogene 2013; 33:4746-55. [PMID: 24096480 PMCID: PMC3979502 DOI: 10.1038/onc.2013.415] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 08/08/2013] [Accepted: 08/15/2013] [Indexed: 12/17/2022]
Abstract
Krüppel-like factor 8 (KLF8) is a transcriptional factor critical for metastatic progression of breast cancer. Epithelial stromal interaction 1 (EPSTI1), a recently identified stromal fibroblast-induced gene in non-invasive breast cancer cells is highly overexpressed in invasive breast carcinomas. The function and regulation of EPSTI1, however, remain largely unknown. In this paper, we report a novel KLF8 to EPSTI1 signaling pathway in breast cancer. Using various expression analyses, we revealed a high co-overexpression of KLF8 and EPSTI1 in invasive human breast cancer cells and patient tumors. Ectopic overexpression of KLF8 in the non-invasive, MCF-10A cells induced the EPSTI1 expression, whereas KLF8 knockdown from the invasive, MDA-MB-231 cells decreased the EPSTI1 expression. Promoter activation and binding analyses indicated that KLF8 promoted the EPSTI1 expression by directly acting on the EPSTI1 gene promoter. EPSTI1 knockdown dramatically reduced the KLF8-promoted MCF-10A cell invasion and ectopic expression of EPSTI1 in the non-invasive, MCF-7 cells is sufficient to induce the cell invasion. Experiments using nude mice demonstrated that the ectopic EPSTI1 granted the MCF-7 cells capability of both invasive growth in the breasts and metastasis to the lungs. Using co-immunoprecipitation coupled with mass spectrometry, we discovered that EPSTI1 interacts with the valosin containing protein (VCP), resulting in the degradation of IκBα and subsequent activation of NF-κB in the nucleus. These findings suggest a novel KLF8 to EPSTI1 to VCP to NF-κB signaling mechanism potentially critical for breast cancer invasion and metastasis.
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Affiliation(s)
- T Li
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - H Lu
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - C Shen
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - S K Lahiri
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - M S Wason
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - D Mukherjee
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - L Yu
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - J Zhao
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
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Abstract
Krüppel-like factors (KLFs) are a family of DNA-binding transcriptional regulators with diverse and essential functions in a multitude of cellular processes, including proliferation, differentiation, migration, inflammation and pluripotency. In this Review, we discuss the roles and regulation of the 17 known KLFs in various cancer-relevant processes. Importantly, the functions of KLFs are context dependent, with some KLFs having different roles in normal cells and cancer, during cancer development and progression and in different cancer types. We also identify key questions for the field that are likely to lead to important new translational research and discoveries in cancer biology.
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Affiliation(s)
- Marie-Pier Tetreault
- Department of Medicine, Gastroenterology Division, University of Pennsylvania Perelman School of Medicine, 913 Biomedical Research Building II/III, 421 Curie Boulevard, Philadelphia PA 19104-6144, USA
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Hatami R, Sieuwerts AM, Izadmehr S, Yao Z, Qiao RF, Papa L, Look MP, Smid M, Ohlssen J, Levine AC, Germain D, Burstein D, Kirschenbaum A, DiFeo A, Foekens JA, Narla G. KLF6-SV1 drives breast cancer metastasis and is associated with poor survival. Sci Transl Med 2013; 5:169ra12. [PMID: 23345610 DOI: 10.1126/scitranslmed.3004688] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metastasis is the major cause of cancer mortality. A more thorough understanding of the mechanisms driving this complex multistep process will aid in the identification and characterization of therapeutically targetable genetic drivers of disease progression. We demonstrate that KLF6-SV1, an oncogenic splice variant of the KLF6 tumor suppressor gene, is associated with increased metastatic potential and poor survival in a cohort of 671 lymph node-negative breast cancer patients. KLF6-SV1 overexpression in mammary epithelial cell lines resulted in an epithelial-to-mesenchymal-like transition and drove aggressive multiorgan metastatic disease in multiple in vivo models. Additionally, KLF6-SV1 loss-of-function studies demonstrated reversion to an epithelial and less invasive phenotype. Combined, these findings implicate KLF6-SV1 as a key driver of breast cancer metastasis that distinguishes between indolent and lethal early-stage disease and provides a potential therapeutic target for invasive breast cancer.
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Affiliation(s)
- Raheleh Hatami
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, New York, NY 10029, USA
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Xia H, Wang C, Chen W, Zhang H, Chaudhury L, Zhou Z, Liu R, Chen C. Kruppel-like factor 5 transcription factor promotes microsomal prostaglandin E2 synthase 1 gene transcription in breast cancer. J Biol Chem 2013; 288:26731-40. [PMID: 23913682 DOI: 10.1074/jbc.m113.483958] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The KLF5 (Krüppel-like factor 5) transcription factor is specifically expressed in a subset of estrogen receptor α-negative breast cancers. Although KLF5 promotes breast cancer cell cycle progression, survival, and tumorigenesis, the mechanism by which KLF5 promotes breast cancer is still not entirely understood. Here, we demonstrate that mPGES1, encoding microsomal prostaglandin E2 synthase 1 (mPGES1), is a KLF5 direct downstream target gene. KLF5 overexpression or knockdown positively altered the levels of mPGES1 mRNA and protein in multiple breast cell lines. 12-O-Tetradecanoylphorbol-13-acetate induced the expression of both KLF5 and mPGES1 in dosage- and time-dependent manners. The induction of KLF5 was essential for 12-O-tetradecanoylphorbol-13-acetate to induce mPGES1 expression. Additionally, KLF5 bound to the mPGES1 gene proximal promoter and activated its transcription. Both KLF5 and mPGES1 promoted prostaglandin E2 production; regulated p21, p27, and Survivin downstream gene expression; and likewise stimulated cell proliferation. Overexpression of mPGES1 partially rescued the KLF5 knockdown-induced downstream gene expression changes and growth arrest in MCF10A cells. Finally, we demonstrate that the expression of mPGES1 was positively correlated with the estrogen receptor α/progesterone receptor/HER2 triple-negative status. These findings suggest that mPGES1 is a target gene of KLF5, making it a new biomarker and a potential therapeutic target for triple-negative breast cancers.
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Affiliation(s)
- Houjun Xia
- From the Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences and Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
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Lu H, Hu L, Yu L, Wang X, Urvalek AM, Li T, Shen C, Mukherjee D, Lahiri SK, Wason MS, Zhao J. KLF8 and FAK cooperatively enrich the active MMP14 on the cell surface required for the metastatic progression of breast cancer. Oncogene 2013; 33:2909-17. [PMID: 23812425 PMCID: PMC3929536 DOI: 10.1038/onc.2013.247] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 04/24/2013] [Accepted: 05/19/2013] [Indexed: 12/13/2022]
Abstract
Krüppel-like factor 8 (KLF8) regulates critical gene transcription associated with cancer. The underlying mechanisms, however, remain largely unidentified. We have recently demonstrated that KLF8 expression enhances the activity but not expression of matrix metalloproteinase-2 (MMP2), the target substrate of MMP14. Here, we report a novel KLF8 to MMP14 signaling that promotes human breast cancer invasion and metastasis. Using cell lines for inducible expression and knockdown of KLF8, we demonstrate that KLF8 promotes MMP14 expression at the transcriptional level. Knocking down KLF8 expression inhibited the breast cancer cell invasion both in vitro and in vivo as well as the lung metastasis in mice, which could be rescued by ectopic expression of MMP14. Promoter reporter assays and oligonucleotide and chromatin immunoprecipitations determined that KLF8 activates the human MMP14 gene promoter by both directly acting on the promoter and indirectly via promoting the nuclear translocation of β-catenin, the expression of T-cell factor-1 (TCF1) and subsequent activation of the promoter by the β-catenin/TCF1 complex. Inhibition of focal adhesion kinase (FAK) using pharmacological inhibitor, RNA interference or knockout showed that the cell surface presentation of active MMP14 downstream of KLF8 depends on FAK expression and activity. Taken together, this work identified novel signaling mechanisms by which KLF8 and FAK work together to promote the extracellular activity of MMP14 critical for breast cancer metastasis.
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Affiliation(s)
- H Lu
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - L Hu
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - L Yu
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - X Wang
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - A M Urvalek
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - T Li
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - C Shen
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - D Mukherjee
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - S K Lahiri
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - M S Wason
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - J Zhao
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
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Bin Z, Ke-Yi L, Wei-Feng Z, Li-Cheng J, Xian-Bin L, Chun-Peng X, Dao-Ying Y, Shu-Wei L. Downregulation of KLF8 expression by shRNA induces inhibition of cell proliferation in CAL27 human oral cancer cells. Med Oral Patol Oral Cir Bucal 2013; 18:e591-6. [PMID: 23722127 PMCID: PMC3731086 DOI: 10.4317/medoral.18736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 02/22/2013] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES KLF8 is a member of KLF transcription factors which play an important tolr in oncogenesis. It is barely expressed in normal human epithelial cells but highly overexpressed in several types of human cancer cell lines. In the present study, we investigate the role of KLF8 in oral cancer and the effects of KLF8 knockdown via lentivirus mediated siRNA infection in human adenosquamos carcinoma CAL 27 cells. STUDY DESIGN We developed a vector-based siRNA expression system that can induce RNAi in CAL 27 oral cancer cells. Downregulation of KLF8 was confirmed by evaluating GFP expressions, RT-PCR and western blot analysis. Finally, the effects of KLF8 downregulation were analyzed by MTT assay and colony formation assays. RESULTS The expression levels of KLF8 mRNA and proteins are reduced in CAL 27 cells that transfected with 21-nt siRNA against KLF8. Lentivirus-mediated silencing of KLF8 reduces cell proliferation and colonies number, thereby indicating the role of KLF8 in cell proliferation and tumorigenesis. CONCLUSIONS These results strongly suggest that KLF8 is essential for growth of CAL 27 cancer cells. A better understanding of KLF8 function and processing may provide novel insights into the clinical therapy of oral cancer.
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Affiliation(s)
- Zhang Bin
- Department of Anatomy, Shandong University School of Medicine, Jinan 250012, Shandong Province, PR China
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Generation of mice deficient in both KLF3/BKLF and KLF8 reveals a genetic interaction and a role for these factors in embryonic globin gene silencing. Mol Cell Biol 2013; 33:2976-87. [PMID: 23716600 DOI: 10.1128/mcb.00074-13] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Krüppel-like factors 3 and 8 (KLF3 and KLF8) are highly related transcriptional regulators that bind to similar sequences of DNA. We have previously shown that in erythroid cells there is a regulatory hierarchy within the KLF family, whereby KLF1 drives the expression of both the Klf3 and Klf8 genes and KLF3 in turn represses Klf8 expression. While the erythroid roles of KLF1 and KLF3 have been explored, the contribution of KLF8 to this regulatory network has been unknown. To investigate this, we have generated a mouse model with disrupted KLF8 expression. While these mice are viable, albeit with a reduced life span, mice lacking both KLF3 and KLF8 die at around embryonic day 14.5 (E14.5), indicative of a genetic interaction between these two factors. In the fetal liver, Klf3 Klf8 double mutant embryos exhibit greater dysregulation of gene expression than either of the two single mutants. In particular, we observe derepression of embryonic, but not adult, globin expression. Taken together, these results suggest that KLF3 and KLF8 have overlapping roles in vivo and participate in the silencing of embryonic globin expression during development.
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Yang Z, Bai B, Luo X, Xiao X, Liu X, Ding Y, Zhang H, Gao L, Li J, Qi H. Downregulated Krüppel-like factor 8 is involved in decreased trophoblast invasion under hypoxia-reoxygenation conditions. Reprod Sci 2013; 21:72-81. [PMID: 23703536 DOI: 10.1177/1933719113488448] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Krüppel-like factor 8 (KLF8) is a pivotal transcription factor expressed in the human placenta that can regulate cell invasion. The objective of this study was to assess whether a hypoxia-reoxygenation (H/R) environment affects placental KLF8 expression levels and subcellular localization and to evaluate the relationship between KLF8 levels and trophoblast invasion activity. Human first trimester villous tissues from normal pregnancies and third trimester placentas from pregnancies with or without preeclampsia (PE) were used for the detection of KLF8 expression and correlating its levels with metalloproteinase 9 (MMP-9) expression. In addition, HTR8/SVneo cells were used to mimic the effects of an H/R environment on placentas to study KLF8 expression and trophoblast invasion. The KLF8 levels, MMP-9 levels, and trophoblast invasion were similarly altered; the levels peaked at 8 to 10 weeks of gestation and declined thereafter along with oxygen tension increased from hypoxia to normoxia during early pregnancy, decreased in third trimester placentas from PE pregnancies featured by repeated H/R and HTR8/SVneo cells exposed to H/R compared with the control. Moreover, a visible reduction in KLF8 immunoreactivity was present in the nuclei of cytotrophoblast cells in human villous tissues at 11 weeks, and partial cytoplasmic accumulation of KLF8 was observed in HTR8/SVneo cells treated with H/R. In conclusion, these findings strongly suggest that H/R reduces the expression and nuclear localization of KLF8 to inhibit the trophoblast invasion by downregulating MMP-9 levels. The KLF8 may play a vital role in the pathogenesis of PE as a novel oxygen tension sensor.
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Affiliation(s)
- Zhongmei Yang
- 1Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
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Zhang H, Liu L, Wang Y, Zhao G, Xie R, Liu C, Xiao X, Wu K, Nie Y, Zhang H, Fan D. KLF8 involves in TGF-beta-induced EMT and promotes invasion and migration in gastric cancer cells. J Cancer Res Clin Oncol 2013; 139:1033-42. [PMID: 23504025 DOI: 10.1007/s00432-012-1363-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 12/10/2012] [Indexed: 12/30/2022]
Abstract
PURPOSE Krüppel-like factor 8 (KLF8), a downstream transcription factor of transforming growth factor-β1 (TGF-β1), has a role in tumorigenesis, tumor progress and epithelial-to-mesenchymal transition (EMT) induction. Recent studies mainly focused on its role in breast cancer and hepatocellular carcinoma; however, little is studied in gastric cancer. Here, we aim to explore whether KLF8 is involved in TGF-β1-induced EMT in gastric cancer cells. METHODS Western blot and real-time PCR assays were used to detect the expression of KLF8, E-cadherin and vimentin in gastric cancer cell line SGC7901 treated with or without TGF-β1. The lentivirus-mediated RNA interference technique was used to knock down the expression of KLF8 in gastric cancer cell line SGC7901. In vitro, the ability of cell migration and invasion were measured by transwell and wound healing assays; the cell motility was detected by high content screening assay. RESULTS TGF-β1 could induce EMT via down-regulating E-cadherin and up-regulating vimentin expression in gastric cancer cells. Further study found that TGF-β1 could induce KLF8 expression at the protein and mRNA levels in gastric cancer cells (P < 0.05). Western blot and real-time PCR assays found that small interference RNA (siRNA)-mediated KLF8 silence blocked TGF-β1-induced EMT-like transformation and subsequently reversed the loss of E-cadherin and gain of vimentin. In vitro, inhibition of KLF8 decreased TGF-β1-prompted cell migration, invasion and motility. CONCLUSIONS KLF8, a transcription factor, is involved in TGF-β1-induced EMT in gastric cancer cells and may be a novel therapeutic target for the treatment of gastric cancer.
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Affiliation(s)
- Hui Zhang
- State Key Laboratory of Cancer Biology, Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, 15 West Changle Road, Xi'an, 710032, China
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Krüppel-like factor 8 is a novel androgen receptor co-activator in human prostate cancer. Acta Pharmacol Sin 2013; 34:282-8. [PMID: 23023312 DOI: 10.1038/aps.2012.130] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
AIM Krüppel-like factor 8 (KLF8) plays important roles in cell cycle and oncogenic transformation. On other hand, androgen receptor (AR) is crucial in development of both androgen-dependent and independent prostatic malignancies. The aim of this study is to investigate the role of KLF8 in prostate cancer (PCa) and the relationship between KLF8 and AR. METHODS Eight human PCa cell lines, including androgen-dependent LNCap cells and androgen-independent 22Rv1 cells, as well as human PCa samples were studied. LNCap cells and 22Rv1 cells were transfected with plasmids encoding full-length wild-type KLF8 or KLF8 shRNA. The expression of KLF8 protein was detected using Western blotting or immunohistochemical staining. Cell proliferation in vitro was measured with MTT assay, and in vivo in a xenograft nude mouse model. Yeast two-hybrid screening, co-immunoprecipitation and pull down assays were used to examine the binding of KLF8 to AR. Luciferase reporter gene assay was used to measure the transcriptional activity of the genes targeted by AR. RESULTS In 133 human PCa samples, KLF8 protein staining was observed in 92.65% (63/68) of high-grade PCa, 66.15% (43/65) of low-grade PCa, and 6.82% (3/44) of adjacent normal tissues. The expression of KLF8 was significantly associated with poorer overall survival. Overexpression of KLF8 enhanced the proliferation of both LNCap and 22Rv1 cells, while knockdown of endogenous KLF8 suppressed the proliferation. These manipulations exerted similar effects on the tumor volumes in the xenograft nude mouse model. Yeast two-hybrid screening revealed that KLF8 was a novel AR-interacting protein. With pull down assay and co-immunoprecipitation assay, we demonstrated that KLF8 bound directly to AR, and KLF8 enhanced AR target gene transcription. CONCLUSION The results demonstrate that KLF8 is a novel AR transcriptional co-activator that is overexpressed in PCa and may play a role in progression of hormone-refractory PCa.
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Transformation of human ovarian surface epithelial cells by Krüppel-like factor 8. Oncogene 2012; 33:10-8. [PMID: 23222713 PMCID: PMC3975924 DOI: 10.1038/onc.2012.545] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 09/07/2012] [Accepted: 10/23/2012] [Indexed: 12/30/2022]
Abstract
Previously we demonstrated that Krüppel-like factor 8 (KLF8) participates in oncogenic transformation of mouse fibroblasts and is highly overexpressed in human ovarian cancer. In this work, we first correlated KLF8 overexpression with the aggressiveness of ovarian patient tumors and then tested if KLF8 could transform human ovarian epithelial cells. Using the immortalized non-tumorigenic human ovarian surface epithelial cell line T80 and retroviral infection, we generated cell lines that constitutively overexpress KLF8 alone or its combination with the known ovarian oncogenes c-Myc, Stat3c and/or Akt and examined the cell lines for anchorage-independent growth and tumorigenesis. The soft agar clonogenic assay showed that T80/KLF8 cells formed significantly more colonies than the mock cells. Interestingly, the cells expressing both KLF8 and c-Myc formed the largest amounts of colonies greater than the sum of colonies formed by the cells expressing KLF8 and c-Myc alone. These results suggested that KLF8 might be a weak oncogene that works cooperatively with c-Myc to transform ovarian cells. Surprisingly, overexpression of KLF8 alone was sufficient to induce tumorigenesis in nude mice resulting in short life span whether the T80/KLF8 cells were injected subcutaneously, intraperitoneally or orthotopically into the ovarian bursa. Histopathological studies confirmed that the T80/KLF8 tumors were characteristic of human serous ovarian carcinomas. Comparative expression profiling and functional studies identified the cell cycle regulators cyclin D1 and USP44 as primary KLF8 targets and effectors for the T80 transformation. Overall, we identified KLF8 overexpression as an important factor in human ovarian carcinoma pathogenesis.
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Lu H, Hu L, Li T, Lahiri S, Shen C, Wason MS, Mukherjee D, Xie H, Yu L, Zhao J. A novel role of Krüppel-like factor 8 in DNA repair in breast cancer cells. J Biol Chem 2012; 287:43720-9. [PMID: 23105099 DOI: 10.1074/jbc.m112.418053] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Krüppel-like factor 8 (KLF8) regulates critical gene transcription and cellular events associated with cancer. However, the role of KLF8 in cancer remains largely unknown. Here, we report a surprisingly novel role for KLF8 in DNA repair in breast cancer cells. Comet, clonogenic, and WST-1 assays showed that KLF8 expression is required for protecting human breast cancer cells from doxorubicin-induced DNA damage and cell death. Western blotting indicated that overexpression of ectopic KLF8 attenuated the levels of the DNA damage marker γH2A.X in doxorubicin-treated PARP-1(+/+) but not PARP-1(-/-) mouse embryonic fibroblasts, whereas the PARP-1-binding-defective KLF8 mutant failed to do so. Interestingly, in response to the DNA damage, KLF8 was phosphorylated by the DNA-dependent protein kinase catalytic subunit and, subsequently, SUMOylated by SUMO E3 ligases protein inhibitors of activated STAT (PIASs), which depends upon the interaction of KLF8 with DNA-dependent protein kinase catalytic subunit, PIASs, and PARP-1 as well as their enzymatic activities. Lastly, we show evidence that KLF8 was recruited to the DNA damage site. These results suggest a novel role and mechanism for KLF8 in the regulation of DNA repair and therapeutic resistance in breast cancer cells.
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Affiliation(s)
- Heng Lu
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, Florida 32827, USA
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Lentivirus-mediated gene silencing of KLF8 reduced the proliferation and invasion of gastric cancer cells. Mol Biol Rep 2012; 39:9809-15. [PMID: 22766838 DOI: 10.1007/s11033-012-1847-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Accepted: 06/11/2012] [Indexed: 01/01/2023]
Abstract
Kruppel-like factor 8 (KLF8) is a transcription factor which has been identified to play a critical role in oncogenic transformation, epithelial-mesenchymal transition and invasion. Higher expression level of KLF8 has been observed in ovarian, renal and breast cancer cells. This study focused on investigating the knockdown effects of KLF8 through lentivirus mediated targeted disruption of KLF8 in gastric cancer cell lines. The expression level of KLF8 is much higher in gastric cancer cells than that in normal cell via Western blot analysis. The decreased expression level of KLF8 after repression was confirmed by real-time PCR and Western blot in SGC-7901, a gastric cancer cell line. The effects of KLF8 deletion on cell proliferation and cell cycle were analyzed by MTT assay and flow cytometry, respectively. Finally, the effects of KLF8 deletion on cell apoptosis and invasion of gastric cancer cells were analyzed by Annexin staining and transwell assay, respectively. It was observed that knockdown of KLF8 reduced the cellular proliferation of SGC-7901 gastric cancer cells, a phenotype at least partially due to cell cycle arrest at G1 phase and increased apoptosis. Furthermore, the inhibition of KLF8 reduces the invasion rates of the cancer cells. Therefore, KLF8 is necessary for cell survival and invasion in gastric cancer cells. The absence of KLF8 may lead to cancer cell death. These results demonstrated that the lentivirus mediated targeted disruption of KLF8 would be an promising therapeutic method for treatment of gastric cancer.
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Yang T, Cai SY, Zhang J, Lu JH, Lin C, Zhai J, Wu MC, Shen F. Krüppel-like factor 8 is a new Wnt/beta-catenin signaling target gene and regulator in hepatocellular carcinoma. PLoS One 2012; 7:e39668. [PMID: 22761862 PMCID: PMC3384617 DOI: 10.1371/journal.pone.0039668] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 05/24/2012] [Indexed: 12/31/2022] Open
Abstract
Krüppel-like factor 8 (KLF8) plays important role in cell cycle and oncogenic transformation. Here we report the mechanisms by which KLF8 crosstalks with Wnt/β-catenin signaling pathway and regulates hepatocellular carcinoma (HCC) cells proliferation. We show that overexpression of KLF8 and nucleus accumulation of β-catenin in the human HCC samples are positively correlated. More importantly, KLF8 protein levels plus nucleus accumulation of β-catenin levels were significantly elevated in high-grade HCC compared to low-grade HCC. Using HCC HepG2 cells we find that, on the one hand both protein and mRNA of KLF8 are up-regulated under Wnt3a stimulation, on the other hand overexpression of KLF8 increases the cytoplasm and nucleus accumulation of β-catenin, recruits p300 to β-catenin/T-cell factor 4 (TCF4) transcription complex, enhances TOP flash report gene transcription, and induces Wnt/β-catenin signaling target genes c-Myc, cyclin D1 and Axin1 expression. Knockdown of KLF8 using shRNA inhibits Wnt3a induced transcription of TOP flash report gene and expression of c-Myc, cyclin D1 and Axin1. Knockdown of β-catenin by shRNA rescues the enhanced HepG2 and Hep3B cells proliferation ability induced by overexpression of KLF8.
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Affiliation(s)
- Tian Yang
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Sheng-Yun Cai
- Department of Gynaecology and Obstetrics, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Jin Zhang
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Jun-Hua Lu
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Chuan Lin
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Jian Zhai
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Meng-Chao Wu
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Feng Shen
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
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Krüppel-like factor 8 (KLF8) is expressed in gliomas of different WHO grades and is essential for tumor cell proliferation. PLoS One 2012; 7:e30429. [PMID: 22276196 PMCID: PMC3261906 DOI: 10.1371/journal.pone.0030429] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Accepted: 12/20/2011] [Indexed: 11/19/2022] Open
Abstract
Krüppel-like factor 8 (KLF8) has only recently been identified to be involved in tumor cell proliferation and invasion of several different tumor entities like renal cell carcinoma, hepatocellular carcinoma and breast cancer. In the present study, we show for the first time the expression of KLF8 in gliomas of different WHO grades and its functional impact on glioma cell proliferation. In order to get information about KLF8-mRNA regulation qPCR was performed and did not reveal any significant difference in samples (n = 10 each) of non-neoplastic brain (NNB), low-grade gliomas (LGG, WHO°II) and glioblastomas (GBM, WHO°IV). Immunohistochemistry of tissue samples (n = 7 LGG, 11 AA and 12 GBM) did not show any significant difference in the fraction of KLF8-immunopositive cells of all analyzed cells in LGG (87%), AA (80%) or GBM (89%). Tissue samples from cerebral breast cancer metastasis, meningiomas but also non-neoplastic brain demonstrated comparable relative cell counts as well. Moreover, there was no correlation between KLF8 expression and the expression pattern of the assumed proliferation marker Ki67, which showed high variability between different tumor grade (9% (LGG), 6% (AA) and 15% (GBM) of Ki67-immunopositive cells). Densitometric analysis of Western blotting revealed that the relative amount of KLF8-protein did also not differ between the highly aggressive and proliferative GBM (1.05) compared to LGG (0.93; p<0.05, studens t-test). As demonstrated for some other non-glial cancer entities, KLF8-knockdown by shRNA in U87-MG cells confirmed its functional relevance, leading to an almost complete loss of tumor cell proliferation. Selective blocking of KLF8 might represent a novel anti-proliferative treatment strategy for malignant gliomas. Yet, its simultaneous expression in non-proliferating tissues could hamper this approach.
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Liu L, Liu N, Xu M, Liu Y, Min J, Pang H, Zhang N, Zhang H, Zhang H. Lentivirus-delivered Krüppel-like factor 8 small interfering RNA inhibits gastric cancer cell growth in vitro and in vivo. Tumour Biol 2011; 33:53-61. [PMID: 22081373 DOI: 10.1007/s13277-011-0245-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 09/23/2011] [Indexed: 12/31/2022] Open
Abstract
We found that the transcription factor Krüppel-like factor 8 (KLF8) was highly expressed in gastric cancer tissues and cell lines compared with adjacent noncancerous regions and gastric epithelial mucosa cells. We employed a lentivirus-mediated RNAi technique to knockdown KLF8 expression in gastric cancer cell line SGC7901 and observed its effects on cell growth in vitro and in vivo. Knockdown of KLF8 inhibited SGC7901 cell proliferation, promoted cell apoptosis, inhibited the tumorigenicity of SGC7901 cells, and significantly decreased tumor growth when the cells were injected into nude mice. These results indicated that overexpression of KLF8 may influence the biological behavior of SGC7901 gastric cancer cells. Knockdown of KLF8 expression by lentivirus-delivered siRNA may be useful as a therapeutic agent for the treatment of gastric cancer.
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Affiliation(s)
- Lili Liu
- Department of Oncology, Tangdu Hospital, Fourth Military Medical University, 1 Xinsi Road, Xi'an 710038, China
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