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MED28 Over-Expression Shortens the Cell Cycle and Induces Genomic Instability. Int J Mol Sci 2019; 20:ijms20071746. [PMID: 30970566 PMCID: PMC6479353 DOI: 10.3390/ijms20071746] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/06/2019] [Accepted: 04/08/2019] [Indexed: 01/01/2023] Open
Abstract
The mammalian mediator complex subunit 28 (MED28) is overexpressed in a variety of cancers and it regulates cell migration/invasion and epithelial-mesenchymal transition. However, transcription factors that increase MED28 expression have not yet been identified. In this study, we performed a luciferase reporter assay to identify and characterize the prospective transcription factors, namely E2F transcription factor 1, nuclear respiratory factor 1, E-26 transforming sequence 1, and CCAAT/enhancer-binding protein β, which increased MED28 expression. In addition, the release from the arrest at the G1−S or G2−M phase transition after cell cycle synchronization using thymidine or nocodazole, respectively, showed enhanced MED28 expression at the G1−S transition and mitosis. Furthermore, the overexpression of MED28 significantly decreased the duration of interphase and mitosis. Conversely, a knockdown of MED28 using si-RNA increased the duration of interphase and mitosis. Of note, the overexpression of MED28 significantly increased micronucleus and nuclear budding in HeLa cells. In addition, flow cytometry and fluorescence microscopy analyses showed that the overexpression of MED28 significantly increased aneuploid cells. Taken together, these results suggest that MED28 expression is increased by oncogenic transcription factors and its overexpression disturbs the cell cycle, which results in genomic instability and aneuploidy.
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Cho JG, Park S, Lim CH, Kim HS, Song SY, Roh TY, Sung JH, Suh W, Ham SJ, Lim KH, Park SG. ZNF224, Krüppel like zinc finger protein, induces cell growth and apoptosis-resistance by down-regulation of p21 and p53 via miR-663a. Oncotarget 2018; 7:31177-90. [PMID: 27105517 PMCID: PMC5058748 DOI: 10.18632/oncotarget.8870] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/31/2016] [Indexed: 11/25/2022] Open
Abstract
ZNF224 is a Krüppel-associated box-containing zinc-finger protein which represses gene transcription by interacting with various co-repressors. However, its consensus DNA sequences and target genes are not fully identified. In this study, we identified and characterized consensus DNA sequences containing 5′-CAGC-3′; recognized by ZNF224 through ChIP-sequencing, which further confirmed by ELISA, SPR, qPCR, and luciferase activity assay. ZNF224 increased miR-663a transcription by binding to miR-663a promoter, which in turn binds to 3′; UTR of p53 and p21 to decrease their expression. miR-663a antagonist abolished ZNF224-mediated suppression of p21 and p53, resulting in the enhanced apoptosis by CPT. The analyses using human breast ductal carcinoma tissues exhibited that the expression of ZNF224 and miR-663a was increased in cancer compared to non-cancer region. Consequently, ZNF224 increases cell survival and decreases apoptosis by decreasing the expression of p53 and p21 via miR-663a as a transcriptional activator. Taken together, we identified and characterized DNA binding element of ZNF224, and its target genes, miR-663a, which provides a novel insight in the down-regulation of p21 and p53 via miR-663a by ZNF224 in breast cancer.
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Affiliation(s)
- Jin Gu Cho
- Department of Biomedical Science, CHA University, Sungnam-si, Gyunggi-do, Korea.,Laboratory for Tracing of Gene Function, Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyunggi-do, Korea
| | - Seho Park
- Department of Surgery, Yonsei University College of Medicine, Seoul, Korea
| | - Chae Hyun Lim
- Division of Integrative Biosciences & Biotechnology, Pohang University of Science & Technology (POSTECH), Pohang, Gyeongbuk, Korea
| | - Hong Sook Kim
- Laboratory for Tracing of Gene Function, Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyunggi-do, Korea
| | - Seung Yong Song
- Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Seoul, Korea
| | - Tae-Young Roh
- Division of Integrative Biosciences & Biotechnology, Pohang University of Science & Technology (POSTECH), Pohang, Gyeongbuk, Korea
| | - Jong-Hyuk Sung
- Department of Pharmacy, College of Pharmacy, Yonsei University, Incheon, Korea
| | - Wonhee Suh
- Department of Pharmacy, College of Pharmacy, Chung-Ang University, Seoul, Korea
| | - Seok-Jin Ham
- Division of Integrative Biosciences & Biotechnology, Pohang University of Science & Technology (POSTECH), Pohang, Gyeongbuk, Korea
| | - Key-Hwan Lim
- Laboratory for Tracing of Gene Function, Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyunggi-do, Korea
| | - Sang Gyu Park
- Laboratory for Tracing of Gene Function, Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyunggi-do, Korea
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Cho JG, Lim KH, Park SG. MED28 increases the colony-forming ability of breast cancer cells by stabilizing the ZNF224 protein upon DNA damage. Oncol Lett 2017; 15:3147-3154. [PMID: 29435049 DOI: 10.3892/ol.2017.7718] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 11/07/2017] [Indexed: 12/31/2022] Open
Abstract
The regulation of gene expression by transcription factors serves a critical function in cell proliferation. Zinc-finger protein 224 (ZNF224), a Krüppel-associated-box-containing zinc finger protein, is known to serve a crucial function in integrating the transcriptional co-factors that activate transcriptional regulation pathways in the cell. A previous study demonstrated that ZNF224 enhances cell proliferation by downregulating the expression of p21 and p53. The present study identified mediator complex subunit 28 (MED28) as a potential binding partner for ZNF224; this was confirmed by co-immunoprecipitation and a surface plasmon resonance assay. Additionally, the KRAB domain at the N-terminal of ZNF224 interacts with the MED domain of MED28. Bimolecular fluorescence complementation analysis revealed that ZNF224 associates with MED28 in the nucleus. In addition, ZNF224 was rapidly degraded upon treatment with the DNA-damaging agent camptothecin (CPT). Transient overexpression of MED28 inhibited the CPT-mediated degradation of ZNF224, resulting in increased colony formation by MCF-7 cells. The molecular mechanisms that underlie the biological outcomes of MED28 expression have not yet been fully elucidated. The present study provides molecular evidence for the function of ZNF224 and MED28 in the DNA-damage response.
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Affiliation(s)
- Jin Gu Cho
- Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyeonggi-do 443-749, Republic of Korea
| | - Key-Hwan Lim
- Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyeonggi-do 443-749, Republic of Korea
| | - Sang Gyu Park
- Department of Pharmacy, College of Pharmacy, Ajou University, Suwon, Gyeonggi-do 443-749, Republic of Korea
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