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Deng L, Liao L, Zhang YL, Yang SY, Hu SY, Andriani L, Ling YX, Ma XY, Zhang FL, Shao ZM, Li DQ. SF3A2 promotes progression and cisplatin resistance in triple-negative breast cancer via alternative splicing of MKRN1. SCIENCE ADVANCES 2024; 10:eadj4009. [PMID: 38569025 PMCID: PMC10990288 DOI: 10.1126/sciadv.adj4009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 02/28/2024] [Indexed: 04/05/2024]
Abstract
Triple-negative breast cancer (TNBC) is the deadliest subtype of breast cancer owing to the lack of effective therapeutic targets. Splicing factor 3a subunit 2 (SF3A2), a poorly defined splicing factor, was notably elevated in TNBC tissues and promoted TNBC progression, as confirmed by cell proliferation, colony formation, transwell migration, and invasion assays. Mechanistic investigations revealed that E3 ubiquitin-protein ligase UBR5 promoted the ubiquitination-dependent degradation of SF3A2, which in turn regulated UBR5, thus forming a feedback loop to balance these two oncoproteins. Moreover, SF3A2 accelerated TNBC progression by, at least in part, specifically regulating the alternative splicing of makorin ring finger protein 1 (MKRN1) and promoting the expression of the dominant and oncogenic isoform, MKRN1-T1. Furthermore, SF3A2 participated in the regulation of both extrinsic and intrinsic apoptosis, leading to cisplatin resistance in TNBC cells. Collectively, these findings reveal a previously unknown role of SF3A2 in TNBC progression and cisplatin resistance, highlighting SF3A2 as a potential therapeutic target for patients with TNBC.
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Affiliation(s)
- Ling Deng
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Li Liao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yin-Ling Zhang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Shao-Ying Yang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Shu-Yuan Hu
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Lisa Andriani
- Department of Breast Surgery, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yun-Xiao Ling
- Department of Breast Surgery, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xiao-Yan Ma
- Department of Breast Surgery, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Fang-Lin Zhang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhi-Ming Shao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Breast Surgery, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Shanghai Key Laboratory of Breast Cancer, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Shanghai Key Laboratory of Radiation Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Da-Qiang Li
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Department of Breast Surgery, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Shanghai Key Laboratory of Breast Cancer, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Shanghai Key Laboratory of Radiation Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
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Jin J, He J, Li X, Ni X, Jin X. The role of ubiquitination and deubiquitination in PI3K/AKT/mTOR pathway: A potential target for cancer therapy. Gene 2023; 889:147807. [PMID: 37722609 DOI: 10.1016/j.gene.2023.147807] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/12/2023] [Accepted: 09/15/2023] [Indexed: 09/20/2023]
Abstract
The PI3K/AKT/mTOR pathway controls key cellular processes, including proliferation and tumor progression, and abnormally high activation of this pathway is a hallmark in human cancers. The post-translational modification, such as Ubiquitination and deubiquitination, fine-tuning the protein level and the activity of members in this pathway play a pivotal role in maintaining normal physiological process. Emerging evidence show that the unbalanced ubiquitination/deubiquitination modification leads to human diseases via PI3K/AKT/mTOR pathway. Therefore, a comprehensive understanding of the ubiquitination/deubiquitination regulation of PI3K/AKT/mTOR pathway may be helpful to uncover the underlying mechanism and improve the potential treatment of cancer via targeting this pathway. Herein, we summarize the latest research progress of ubiquitination and deubiquitination of PI3K/AKT/mTOR pathway, systematically discuss the associated crosstalk between them, as well as focus the clinical transformation via targeting ubiquitination process.
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Affiliation(s)
- Jiabei Jin
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Jian He
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Xinming Li
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Xiaoqi Ni
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Xiaofeng Jin
- Department of Biochemistry and Molecular Biology, Zhejiang Key Laboratory of Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang 315211, China.
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Zhang Y, Li QS, Liu HL, Tang HT, Yang HL, Wu DQ, Huang YY, Li LC, Liu LH, Li MX. MKRN1 promotes colorectal cancer metastasis by activating the TGF-β signalling pathway through SNIP1 protein degradation. J Exp Clin Cancer Res 2023; 42:219. [PMID: 37620897 PMCID: PMC10464235 DOI: 10.1186/s13046-023-02788-w] [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: 04/13/2023] [Accepted: 08/03/2023] [Indexed: 08/26/2023] Open
Abstract
BACKGROUND The Makorin ring finger protein 1 (MKRN1) gene, also called RNF61, is located on the long arm of chromosome 7 and is a member of the RING finger protein family. The E3 ubiquitin ligase MKRN1 is closely linked to tumour development, but the exact mechanism needs to be elucidated. In this study, we aimed to investigate the specific mechanism and role of MKRN1 in colorectal cancer (CRC) development. METHODS MKRN1 expression in CRC was analysed using the Cancer Cell Line Encyclopaedia and the Cancer Genome Atlas (TCGA) databases. Rectal tumour tissues were frozen to explore the MKRN1 expression in CRC and its clinical significance. The impact of MKRN1 on CRC cell proliferation and migration was observed using CCK8, colony formation, wound healing, and transwell assays. A combination of MKRN1 quantitative proteomics, ubiquitination modification omics analysis, and a string of in vitro and in vivo experiments revealed the potential mechanisms by which MKRN1 regulates CRC metastasis. RESULTS MKRN1 expression was significantly elevated in CRC tissues compared to paracancerous tissues and was positively linked with prognosis (P < 0.01). MKRN1 downregulation inhibits CRC cell proliferation, migration, and invasion. Conversely, MKRN1 overexpression promotes the proliferation, migration, and invasion of CRC cells. Mechanistically, MKRN1 induces epithelial-mesenchymal transition (EMT) in CRC cells via ubiquitination and degradation of Smad nuclear-interacting protein 1 (SNIP1). Furthermore, SNIP1 inhibits transforming growth factor-β (TGF-β) signalling, and MKRN1 promotes TGF-β signalling by degrading SNIP1 to induce EMT in CRC cells. Finally, using conditional knockout mice, intestinal lesions and metastatic liver microlesions were greatly reduced in the intestinal knockout MKRN1 group compared to that in the control group. CONCLUSIONS High MKRN1 levels promote TGF-β signalling through ubiquitination and degradation of SNIP1, thereby facilitating CRC metastasis, and supporting MKRN1 as a CRC pro-cancer factor. The MKRN1/SNIP1/TGF-β axis may be a potential therapeutic target in CRC.
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Affiliation(s)
- Yi Zhang
- Guizhou Prenatal Diagnosis Center, Affiliated Hospital of Guizhou Medical University, Guiyang, 550004, Guizhou, People's Republic of China
- Department of Clinical Biochemistry, School of Medical Laboratory Science, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China
| | - Qin-Shan Li
- Guizhou Prenatal Diagnosis Center, Affiliated Hospital of Guizhou Medical University, Guiyang, 550004, Guizhou, People's Republic of China.
- Department of Clinical Biochemistry, School of Medical Laboratory Science, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China.
| | - Hong-Lin Liu
- Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing, 100000, People's Republic of China
| | - Hong-Ting Tang
- Department of Clinical Biochemistry, School of Medical Laboratory Science, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China
| | - Han-Lin Yang
- Department of Clinical Biochemistry, School of Medical Laboratory Science, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China
| | - Dao-Qiu Wu
- Department of Clinical Biochemistry, School of Medical Laboratory Science, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China
| | - Yu-Ying Huang
- Department of Clinical Biochemistry, School of Medical Laboratory Science, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China
| | - Li-Cheng Li
- Clinical Medical College, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China
- Department of HematologyGuizhou Province Laboratory of Hematopoietic Stem Cell Transplantation Centre, Affiliated Hospital of Guizhou Medical University, Guizhou Province Institute of Hematology, Guizhou, Guiyang, People's Republic of China
| | - Li-Hong Liu
- Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, People's Republic of China.
| | - Meng-Xing Li
- Clinical Medical College, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China.
- Department of HematologyGuizhou Province Laboratory of Hematopoietic Stem Cell Transplantation Centre, Affiliated Hospital of Guizhou Medical University, Guizhou Province Institute of Hematology, Guizhou, Guiyang, People's Republic of China.
- Department of Pathophysiology, Guizhou Medical University, Guizhou, Guiyang, 550004, People's Republic of China.
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Takahashi T, Ando Y, Ichikawa H, Tsuneyama K, Hijikata T. Serum/glucose starvation strikingly reduces heterogeneous nuclear ribonucleoprotein A1 protein and its target, cyclin D1. FEBS J 2023; 290:4126-4144. [PMID: 37095740 DOI: 10.1111/febs.16802] [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: 01/19/2023] [Revised: 03/14/2023] [Accepted: 04/20/2023] [Indexed: 04/26/2023]
Abstract
Our investigation to explore cellular alterations related to undernutrition in cancer cells revealed that the protein level of heterogenous nuclear ribonucleoprotein A1 (hnRNP A1) is drastically decreased by serum/glucose starvation. Its loss was reversible, serum/glucose starvation-specific and universal throughout cell types and species. The hnRNP A1 mRNA level and hnRNP A1 mRNA/protein stability were not altered under this condition. CCND1 mRNA, which we newly identified as the binding target of hnRNP A1, was decreased by serum/glucose starvation. Under similar conditions, CCND1 protein was reduced in vitro and in vivo, whereas hnRNP A1 mRNA level and CCND1 mRNA level revealed no correlation in most clinical samples. Functional analyses revealed that CCND1 mRNA stability is certainly dependent on hnRNP A1 protein level and that RNA recognition motif-1 (RRM1) in hnRNP A1 plays a central role in maintaining CCND1 mRNA stability and subsequent protein expression. The injection of RRM1-deleted hnRNP A1-expressing cancer cells in the mouse xenograft model did not form any tumours, and that of hnRNP A1-expressing cancer cells retained CCND1 expression at the lesion adjacent to necrosis with a slight increase in tumour volume. Furthermore, RRM1 deletion caused growth suppression with the induction of apoptosis and autophagy, whereas CCND1 restoration completely recovered it. Our results indicate that serum/glucose starvation triggers entire hnRNP A1 protein loss, and its loss may play a role in CCND1 mRNA destabilization and CCND1-mediated cellular event inhibition, i.e. growth promotion, apoptosis induction and autophagosome formation.
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Affiliation(s)
- Tetsuyuki Takahashi
- Department of Anatomy and Cell Biology, Faculty of Pharmacy, Research Institute of Pharmaceutical Sciences, Musashino University, Nishi-Tokyo, Japan
| | - Yuri Ando
- Department of Anatomy and Cell Biology, Faculty of Pharmacy, Research Institute of Pharmaceutical Sciences, Musashino University, Nishi-Tokyo, Japan
| | - Hirona Ichikawa
- Department of Anatomy and Cell Biology, Faculty of Pharmacy, Research Institute of Pharmaceutical Sciences, Musashino University, Nishi-Tokyo, Japan
| | - Koichi Tsuneyama
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Japan
| | - Takao Hijikata
- Department of Anatomy and Cell Biology, Faculty of Pharmacy, Research Institute of Pharmaceutical Sciences, Musashino University, Nishi-Tokyo, Japan
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Yang H, Ai H, Zhang J, Ma J, Liu K, Li Z. UPS: Opportunities and challenges for gastric cancer treatment. Front Oncol 2023; 13:1140452. [PMID: 37077823 PMCID: PMC10106573 DOI: 10.3389/fonc.2023.1140452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/20/2023] [Indexed: 04/05/2023] Open
Abstract
Gastric cancer remains the fourth most frequently diagnosed malignancy and the fifth leading cause of cancer-related mortality worldwide owning to the lack of efficient drugs and targets for therapy. Accumulating evidence indicates that UPS, which consists of E1, E2, and E3 enzymes and proteasome, plays an important role in the GC tumorigenesis. The imbalance of UPS impairs the protein homeostasis network during development of GC. Therefore, modulating these enzymes and proteasome may be a promising strategy for GC target therapy. Besides, PROTAC, a strategy using UPS to degrade the target protein, is an emerging tool for drug development. Thus far, more and more PROTAC drugs enter clinical trials for cancer therapy. Here, we will analyze the abnormal expression enzymes in UPS and summarize the E3 enzymes which can be developed in PROTAC so that it can contribute to the development of UPS modulator and PROTAC technology for GC therapy.
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Affiliation(s)
- Hang Yang
- The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, China
| | - Huihan Ai
- The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, China
| | - Jialin Zhang
- The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, China
| | - Jie Ma
- The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, China
| | - Kangdong Liu
- Department of Pathophysiology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China
- China-US Hormel (Henan) Cancer Institute, Zhengzhou, Henan, China
- Research Center of Basic Medicine, Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China
- *Correspondence: Zhi Li, ; Kangdong Liu,
| | - Zhi Li
- The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, China
- *Correspondence: Zhi Li, ; Kangdong Liu,
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Ntostis P, Swanson G, Kokkali G, Iles D, Huntriss J, Pantou A, Tzetis M, Pantos K, Picton HM, Krawetz SA, Miller D. Trophectoderm non-coding RNAs reflect the higher metabolic and more invasive properties of young maternal age blastocysts. Syst Biol Reprod Med 2023; 69:3-19. [PMID: 36576378 DOI: 10.1080/19396368.2022.2153636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Increasing female age is accompanied by a corresponding fall in her fertility. This decline is influenced by a variety of factors over an individual's life course including background genetics, local environment and diet. Studying both coding and non-coding RNAs of the embryo could aid our understanding of the causes and/or effects of the physiological processes accompanying the decline including the differential expression of sub-cellular biomarkers indicative of various diseases. The current study is a post-hoc analysis of the expression of trophectoderm RNA data derived from a previous high throughput study. Its main aim is to determine the characteristics and potential functionalities that characterize long non-coding RNAs. As reported previously, a maternal age-related component is potentially implicated in implantation success. Trophectoderm samples representing the full range of maternal reproductive ages were considered in relation to embryonic implantation potential, trophectoderm transcriptome dynamics and reproductive maternal age. The long non-coding RNA (lncRNA) biomarkers identified here are consistent with the activities of embryo-endometrial crosstalk, developmental competency and implantation and share common characteristics with markers of neoplasia/cancer invasion. Corresponding genes for expressed lncRNAs were more active in the blastocysts of younger women are associated with metabolic pathways including cholesterol biosynthesis and steroidogenesis.
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Affiliation(s)
- Panagiotis Ntostis
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
- Department of Genetics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Grace Swanson
- Department of Obstetrics and Gynecology, Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Georgia Kokkali
- Genesis Athens Clinic, Reproductive Medicine Unit, Athens, Greece
| | - David Iles
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - John Huntriss
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Agni Pantou
- Genesis Athens Clinic, Reproductive Medicine Unit, Athens, Greece
| | - Maria Tzetis
- Department of Genetics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | | | - Helen M Picton
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Stephen A Krawetz
- Department of Obstetrics and Gynecology, Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
| | - David Miller
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
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Palrasu M, Zaika E, Paulrasu K, Caspa Gokulan R, Suarez G, Que J, El-Rifai W, Peek RM, Garcia-Buitrago M, Zaika AI. Helicobacter pylori pathogen inhibits cellular responses to oncogenic stress and apoptosis. PLoS Pathog 2022; 18:e1010628. [PMID: 35767594 PMCID: PMC9242521 DOI: 10.1371/journal.ppat.1010628] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 05/31/2022] [Indexed: 01/21/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a common gastric pathogen that infects approximately half of the world's population. Infection with H. pylori can lead to diverse pathological conditions, including chronic gastritis, peptic ulcer disease, and cancer. The latter is the most severe consequence of H. pylori infection. According to epidemiological studies, gastric infection with H. pylori is the strongest known risk factor for non-cardia gastric cancer (GC), which remains one of the leading causes of cancer-related deaths worldwide. However, it still remains to be poorly understood how host-microbe interactions result in cancer development in the human stomach. Here we focus on the H. pylori bacterial factors that affect the host ubiquitin proteasome system. We investigated E3 ubiquitin ligases SIVA1 and ULF that regulate p14ARF (p19ARF in mice) tumor suppressor. ARF plays a key role in regulation of the oncogenic stress response and is frequently inhibited during GC progression. Expression of ARF, SIVA1 and ULF proteins were investigated in gastroids, H. pylori-infected mice and human gastric tissues. The role of the H. pylori type IV secretion system was assessed using various H. pylori isogenic mutants. Our studies demonstrated that H. pylori infection results in induction of ULF, decrease in SIVA1 protein levels, and subsequent ubiquitination and degradation of p14ARF tumor suppressor. Bacterial CagA protein was found to sequentially bind to SIVA1 and ULF proteins. This process is regulated by CagA protein phosphorylation at the EPIYA motifs. Downregulation of ARF protein leads to inhibition of cellular apoptosis and oncogenic stress response that may promote gastric carcinogenesis.
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Affiliation(s)
- Manikandan Palrasu
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Elena Zaika
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Kodisundaram Paulrasu
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Ravindran Caspa Gokulan
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Giovanni Suarez
- Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jianwen Que
- Department of Medicine, Columbia University Medical Center, New York, New York, United States of America
| | - Wael El-Rifai
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- Department of Veterans Affairs, Miami VA Healthcare System, Miami, Florida, United States of America
| | - Richard M. Peek
- Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Monica Garcia-Buitrago
- Department of Pathology, University of Miami Miller School of Medicine, Miami, Florida, United States of America
| | - Alexander I. Zaika
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- Department of Veterans Affairs, Miami VA Healthcare System, Miami, Florida, United States of America
- * E-mail:
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Zhao S, Wu Y, Wei Y, Xu X, Zheng J. Identification of Biomarkers Associated With CD8+ T Cells in Coronary Artery Disease and Their Pan-Cancer Analysis. Front Immunol 2022; 13:876616. [PMID: 35799780 PMCID: PMC9254733 DOI: 10.3389/fimmu.2022.876616] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/24/2022] [Indexed: 11/13/2022] Open
Abstract
PurposeTo identify biomarkers associated with CD8+ T cells in coronary artery disease (CAD) and initially explore their potential role in the tumor immune microenvironment.Materials and MethodsCAD-related datasets GSE12288, GSE34198, and GSE66360, were downloaded from the GEO database. First, GSVA was performed based on the GSE12288 dataset. Then WGCNA analysis was performed to identify the most relevant module and candidate hub gene for CD8+ T cells, followed by GO and KEGG analysis of this module. Secondly, the relationship between candidate hub genes and CD8+ T cells was verified using GSE34198 and GSE66360, which led to the identification of hub genes. The relationship of hub genes with CD8+ T cells in cancer was analyzed using the TIMER database. Methylation analysis of hub genes was performed using the DiseaseMeth database. CAD, pan-cancer, pan-cell lines, and pan-normal tissues, correlations between hub genes. In addition, potential drugs and TFs associated with hub genes were predicted, and the ceRNA network was constructed. Finally, GSEA was performed separately for hub genes.ResultsCAD was shown to be associated with immune response by GSVA analysis. WGCNA identified the blue module as most related to CD8+ T cells and identified nine candidate hub genes. The relevance of CAD to immunity was further confirmed by GO and KEGG analysis of the module. Two additional datasets validated and identified three hub genes (FBXO7, RAD23A, and MKRN1) that significantly correlated with CD8+ T cells. In addition, we found that hub genes were positively associated with CD8+ T cells in TGCT, THCA, and KICH cancers by our analysis. Moreover, the hub gene was differentially methylated. We also analyzed the correlation between hub genes in CAD, different cancers, different cell lines, and different normal tissues. The results of all the analyses showed a positive correlation between them. Finally, we successfully constructed hub gene-associated TF-gene and ceRNA networks and predicted 11 drugs associated with hub genes. GSEA suggests that hub genes are related to multiple immune response processes.ConclusionFBXO7, RAD23A, and MKRN1 are significantly associated with CD8+ T cells in CAD and multiple cancers and may act through immune responses in CAD and cancer.
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Affiliation(s)
- Shijian Zhao
- Department of Cardiology, the Affiliated Cardiovascular Hospital of Kunming Medical University (Fuwai Yunnan Cardiovascular Hospital), Kunming, China
| | - Yinteng Wu
- Department of Orthopedic and Trauma Surgery, the First Affiliated Hospital, Guangxi Medical University, Nanning, China
| | - Yantao Wei
- Department of Cardiology, the Affiliated Cardiovascular Hospital of Kunming Medical University (Fuwai Yunnan Cardiovascular Hospital), Kunming, China
| | - Xiaoyu Xu
- Department of Cardiology, the Affiliated Cardiovascular Hospital of Kunming Medical University (Fuwai Yunnan Cardiovascular Hospital), Kunming, China
| | - Jialin Zheng
- Department of Cardiology, the Affiliated Cardiovascular Hospital of Kunming Medical University (Fuwai Yunnan Cardiovascular Hospital), Kunming, China
- *Correspondence: Jialin Zheng,
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Ravi S, Alencar AM, Arakelyan J, Xu W, Stauber R, Wang CCI, Papyan R, Ghazaryan N, Pereira RM. An Update to Hallmarks of Cancer. Cureus 2022; 14:e24803. [PMID: 35686268 PMCID: PMC9169686 DOI: 10.7759/cureus.24803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2022] [Indexed: 12/03/2022] Open
Abstract
In the last decade, there has been remarkable progress in research toward understanding and refining the hallmarks of cancer. In this review, we propose a new hallmark - “pro-survival autophagy.” The importance of pro-survival autophagy is well established in tumorigenesis, as it is related to multiple steps in cancer progression and vital for some cancers. Autophagy is a potential anti-cancer therapeutic target. For this reason, autophagy is a good candidate as a new hallmark of cancer. We describe two enabling characteristics that play a major role in enabling cells to acquire the hallmarks of cancer - “tumor-promoting microenvironment and macroenvironment” and “cancer epigenetics, genome instability and mutation.” We also discuss the recent updates, therapeutic and prognostic implications of the eight hallmarks of cancer described by Hanahan et al. in 2011. Understanding these hallmarks and enabling characteristics is key not only to developing new ways to treat cancer efficiently but also to exploring options to overcome cancer resistance to treatment.
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Liu Y, Luo Y, Yan S, Lian YF, Wu S, Xu M, Feng L, Zhang X, Li R, Zhang X, Feng QS, Zeng YX, Zhang H. CRL2 KLHDC3 mediates p14ARF N-terminal ubiquitylation degradation to promote non-small cell lung carcinoma progression. Oncogene 2022; 41:3104-3117. [PMID: 35468939 DOI: 10.1038/s41388-022-02318-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 03/24/2022] [Accepted: 04/06/2022] [Indexed: 11/09/2022]
Abstract
Kelch superfamily involves a variety of proteins containing multiple kelch motif and is well characterized as substrate adaptors for CUL3 E3 ligases, which play critical roles in carcinogenesis. However, the role of kelch proteins in lung cancer remains largely unknown. In this study, the non-small cell lung cancer (NSCLC) patients with higher expression of a kelch protein, kelch domain containing 3 (KLHDC3), showed worse overall survival. KLHDC3 deficiency affected NSCLC cell lines proliferation in vitro and in vivo. Further study indicated that KLHDC3 mediated CUL2 E3 ligase and tumor suppressor p14ARF interaction, facilitating the N-terminal ubiquitylation and subsequent degradation of p14ARF. Interestingly, Gefitinib-resistant NSCLC cell lines displayed higher KLHDC3 protein levels. Gefitinib and Osimertinib medications were capable of upregulating KLHDC3 expression to promote p14ARF degradation in the NSCLC cell lines. KLHDC3 shortage significantly increased the sensitivity of lung cancer cells to epidermal growth factor receptor (EGFR)-targeted drugs, providing an alternative explanation for the development of Gefitinib and Osimertinib resistance in NSCLC therapy. Our works suggest that CRL2KLHDC3 could be a valuable target to regulate the abundance of p14ARF and postpone the occurrence of EGFR-targeted drugs resistance.
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Affiliation(s)
- Yang Liu
- Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, 510060, China
| | - Yuewen Luo
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,School of Medicine, Sun Yat-sen University, Guangzhou/Shenzhen, 510080, China
| | - Shumei Yan
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Yi-Fan Lian
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Shiyu Wu
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Miao Xu
- Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, 510060, China
| | - Lin Feng
- Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, 510060, China
| | - Xu Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Rong Li
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiantao Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Qi-Sheng Feng
- Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, 510060, China
| | - Yi-Xin Zeng
- Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, 510060, China.
| | - Hui Zhang
- Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.
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11
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Cheng C, Zhang W, Zhang C, Ji P, Wu X, Sha Z, Chen X, Wang Y, Chen Y, Cheng H, Shi L. Hyperoside Ameliorates DSS-Induced Colitis through MKRN1-Mediated Regulation of PPARγ Signaling and Th17/Treg Balance. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:15240-15251. [PMID: 34878764 DOI: 10.1021/acs.jafc.1c06292] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Hyperoside (HYP), a naturally occurring flavonoid compound, exerts multiple biological functions including myocardial protection, antiredox, and anti-inflammatory activities. However, the role of HYP on inflammatory bowel disease (IBD) and the underlying mechanism need to be further established. Here, we show that HYP treatment profoundly alleviated dextran sulfate sodium-induced ulcerative colitis in mice, characterized by reduced pathological scores, preserved tissue integrity, suppressed colonic inflammation, and balanced Th17/Treg response. Mechanistically, HYP was shown to restrain the expression of the E3 ubiquitin ligase, makorin ring finger protein 1 (MKRN1), which in turn promoted the ubiquitination and proteasomal degradation of peroxisome proliferator-activated receptor gamma (PPARγ), an essential regulator of Th17 and Treg differentiation. Consequently, HYP treatment enhanced PPARγ signaling and hence promoted Treg differentiation while suppressing Th17 cell development during colitis. Thus, our data indicate that HYP acts through the MKRN1/PPARγ axis to modulate the Th17/Treg axis and thereby confers protection against experimental colitis. The findings extend our understanding about HYP action and may provide a potential therapeutic target for IBD.
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Affiliation(s)
- Cheng Cheng
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
- The First School of Clinical Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China
| | - Wei Zhang
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Cong Zhang
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
- Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai 200031, China
| | - Peng Ji
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Xiaohui Wu
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Zhou Sha
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Xiang Chen
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Yongkang Wang
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Yugen Chen
- The First School of Clinical Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China
| | - Haibo Cheng
- The First School of Clinical Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China
- Collaborative Innovation Center of Jiangsu Province of Cancer Prevention and Treatment of Chinese Medicine, Nanjing 210023, China
| | - Liyun Shi
- Key Laboratory of Inflammation and Immunoregulation, School of Medicine and Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, China
- Institute of Translational Medicine, Zhejiang Shuren University, Hangzhou 310022, China
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12
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Zhang P, Gao K, Zhang L, Sun H, Zhao X, Liu Y, Lv Z, Shi Q, Chen Y, Jiao D, Li Y, Gu W, Wang C. CRL2-KLHDC3 E3 ubiquitin ligase complex suppresses ferroptosis through promoting p14 ARF degradation. Cell Death Differ 2021; 29:758-771. [PMID: 34743205 DOI: 10.1038/s41418-021-00890-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 09/30/2021] [Accepted: 10/04/2021] [Indexed: 01/22/2023] Open
Abstract
The cystine/glutamate antiporter SLC7A11 (commonly known as xCT) functions to import cystine for glutathione biosynthesis, thereby protecting cells from oxidative stress and ferroptosis, a regulated form of non-apoptotic cell death driven by the accumulation of lipid-based reactive oxygen species (ROS). p14ARF, a well-established tumor suppressor, promotes ferroptosis by inhibiting NRF2-mediated SLC7A11 transcription. Here, we demonstrate the crucial role of Cullin 2 RING E3 ligase (CRL2)-KLHDC3 E3 ubiquitin ligase complex in regulating p14ARF protein stability. KLHDC3 acts as a CRL2 adaptor that specifically recognizes a C-terminal degron in p14ARF and triggers p14ARF for ubiquitin-proteasomal degradation. This regulation mode is absent in the murine p14ARF homolog, p19arf which lacks the C-terminal degron. We also show that KLHDC3 suppresses ferroptosis in vitro and supports tumor growth in vivo by relieving p14ARF-mediated suppression of SLC7A11 transcription. Overall, these findings reveal that the protein stability and pro-ferroptotic function of p14ARF are controlled by a CRL2 E3 ubiquitin ligase complex, and suggest that suppression of the p14ARF-NRF2-SLC7A11 regulatory pathway by KLHDC3 overexpression likely contributes to cancer progression.
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Affiliation(s)
- Pingzhao Zhang
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China. .,Institute for Cancer Genetics, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - Kun Gao
- Department of Clinical Laboratory, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China.
| | - Liang Zhang
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Huiru Sun
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiaying Zhao
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Yajuan Liu
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Zeheng Lv
- Department of Clinical Laboratory, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qing Shi
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Yingji Chen
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Dongyue Jiao
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Yao Li
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China
| | - Wei Gu
- Institute for Cancer Genetics, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - Chenji Wang
- Department of Pathology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, School of Life Sciences, Fudan University, Shanghai, China.
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13
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Repenning A, Happel D, Bouchard C, Meixner M, Verel‐Yilmaz Y, Raifer H, Holembowski L, Krause E, Kremmer E, Feederle R, Keber CU, Lohoff M, Slater EP, Bartsch DK, Bauer U. PRMT1 promotes the tumor suppressor function of p14 ARF and is indicative for pancreatic cancer prognosis. EMBO J 2021; 40:e106777. [PMID: 33999432 PMCID: PMC8246066 DOI: 10.15252/embj.2020106777] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 12/04/2022] Open
Abstract
The p14ARF protein is a well-known regulator of p53-dependent and p53-independent tumor-suppressive activities. In unstressed cells, p14ARF is predominantly sequestered in the nucleoli, bound to its nucleolar interaction partner NPM. Upon genotoxic stress, p14ARF undergoes an immediate redistribution to the nucleo- and cytoplasm, where it promotes activation of cell cycle arrest and apoptosis. Here, we identify p14ARF as a novel interaction partner and substrate of PRMT1 (protein arginine methyltransferase 1). PRMT1 methylates several arginine residues in the C-terminal nuclear/nucleolar localization sequence (NLS/NoLS) of p14ARF . In the absence of cellular stress, these arginines are crucial for nucleolar localization of p14ARF . Genotoxic stress causes augmented interaction between PRMT1 and p14ARF , accompanied by arginine methylation of p14ARF . PRMT1-dependent NLS/NoLS methylation promotes the release of p14ARF from NPM and nucleolar sequestration, subsequently leading to p53-independent apoptosis. This PRMT1-p14ARF cooperation is cancer-relevant and indicative for PDAC (pancreatic ductal adenocarcinoma) prognosis and chemotherapy response of pancreatic tumor cells. Our data reveal that PRMT1-mediated arginine methylation is an important trigger for p14ARF 's stress-induced tumor-suppressive function.
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Affiliation(s)
- Antje Repenning
- Institute for Molecular Biology and Tumor Research (IMT)Philipps‐University MarburgMarburgGermany
| | - Daniela Happel
- Institute for Molecular Biology and Tumor Research (IMT)Philipps‐University MarburgMarburgGermany
| | - Caroline Bouchard
- Institute for Molecular Biology and Tumor Research (IMT)Philipps‐University MarburgMarburgGermany
| | - Marion Meixner
- Institute for Molecular Biology and Tumor Research (IMT)Philipps‐University MarburgMarburgGermany
| | - Yesim Verel‐Yilmaz
- Department of VisceralThoracic and Vascular SurgeryUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
| | - Hartmann Raifer
- Core Facility Flow CytometryUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
- Institute for Med. Microbiology & Hospital HygieneUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
| | - Lena Holembowski
- Institute for Molecular Biology and Tumor Research (IMT)Philipps‐University MarburgMarburgGermany
| | | | - Elisabeth Kremmer
- Institute of Molecular ImmunologyHelmholtz Zentrum MünchenGerman Research Center for Environmental HealthMünchenGermany
| | - Regina Feederle
- Monoclonal Antibody Core FacilityInstitute for Diabetes and ObesityHelmholtz Zentrum MünchenGerman Research Center for Environmental HealthNeuherbergGermany
| | - Corinna U Keber
- Institute for PathologyUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
| | - Michael Lohoff
- Institute for Med. Microbiology & Hospital HygieneUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
| | - Emily P Slater
- Department of VisceralThoracic and Vascular SurgeryUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
| | - Detlef K Bartsch
- Department of VisceralThoracic and Vascular SurgeryUniversity Hospital MarburgPhilipps‐University MarburgMarburgGermany
| | - Uta‐Maria Bauer
- Institute for Molecular Biology and Tumor Research (IMT)Philipps‐University MarburgMarburgGermany
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14
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Zhang Y, Xu J, Fu H, Wei Z, Yang D, Yan R. UBE3C promotes proliferation and inhibits apoptosis by activating the β-catenin signaling via degradation of AXIN1 in gastric cancer. Carcinogenesis 2021; 42:285-293. [PMID: 32930707 DOI: 10.1093/carcin/bgaa098] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/24/2020] [Accepted: 09/12/2020] [Indexed: 12/15/2022] Open
Abstract
Gastric cancer (GC) remains one of the most frequent cancers worldwide. Previous studies have shown that E3 ubiquitin ligase E3C (UBE3C) promotes the progression of multiple types of cancer. However, little is known about the expression and molecular mechanism of UBE3C in GC. In this study, UBE3C is upregulated in clinical GC samples and RNA-seq data from The Cancer Genome Atlas, and the UBE3C upregulation is correlated with poor clinical outcomes in patients with GC. In vitro, knockdown of UBE3C suppresses proliferation and enhances apoptosis in GC cells by inhibiting β-catenin signaling pathway. In contrast, in vitro overexpression of UBE3C promotes GC cell proliferation and inhibits apoptosis through the upregulation of β-catenin signaling by promoting ubiquitination of AXIN1. In vivo, knockdown of UBE3C inhibits tumor growth in a nude mouse model. Concurrently, the UBE3C knockdown resulted in an increase of AXIN1 and a reduction of β-catenin in the nucleus and cytoplasm in the xenograft tumor tissues. Our results demonstrate that UBE3C promotes GC progression through activating the β-catenin signaling via degradation of AXIN1. Our data suggest that UBE3C exerts oncogenic effects in GC and thus provides a promising prognostic biomarker and a potential therapeutic target for GC therapy.
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Affiliation(s)
- Yu Zhang
- Department of Gastrointestinal Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Jiapeng Xu
- Department of Gastrointestinal Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Hongbing Fu
- Department of Gastrointestinal Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Ziran Wei
- Department of Gastrointestinal Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Dejun Yang
- Department of Gastrointestinal Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Ronglin Yan
- Department of Gastrointestinal Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China
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15
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Fang YC, Fu SJ, Hsu PH, Chang PT, Huang JJ, Chiu YC, Liao YF, Jow GM, Tang CY, Jeng CJ. Identification of MKRN1 as a second E3 ligase for Eag1 potassium channels reveals regulation via differential degradation. J Biol Chem 2021; 296:100484. [PMID: 33647316 PMCID: PMC8039722 DOI: 10.1016/j.jbc.2021.100484] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 02/17/2021] [Accepted: 02/25/2021] [Indexed: 11/02/2022] Open
Abstract
Mutations in the human gene encoding the neuron-specific Eag1 voltage-gated K+ channel are associated with neurodevelopmental diseases, indicating an important role of Eag1 during brain development. A disease-causing Eag1 mutation is linked to decreased protein stability that involves enhanced protein degradation by the E3 ubiquitin ligase cullin 7 (CUL7). The general mechanisms governing protein homeostasis of plasma membrane- and endoplasmic reticulum (ER)-localized Eag1 K+ channels, however, remain unclear. By using yeast two-hybrid screening, we identified another E3 ubiquitin ligase, makorin ring finger protein 1 (MKRN1), as a novel binding partner primarily interacting with the carboxyl-terminal region of Eag1. MKRN1 mainly interacts with ER-localized immature core-glycosylated, as well as nascent nonglycosylated, Eag1 proteins. MKRN1 promotes polyubiquitination and ER-associated proteasomal degradation of immature Eag1 proteins. Although both CUL7 and MKRN1 contribute to ER quality control of immature core-glycosylated Eag1 proteins, MKRN1, but not CUL7, associates with and promotes degradation of nascent, nonglycosylated Eag1 proteins at the ER. In direct contrast to the role of CUL7 in regulating both ER and peripheral quality controls of Eag1, MKRN1 is exclusively responsible for the early stage of Eag1 maturation at the ER. We further demonstrated that both CUL7 and MKRN1 contribute to protein quality control of additional disease-causing Eag1 mutants associated with defective protein homeostasis. Our data suggest that the presence of this dual ubiquitination system differentially maintains Eag1 protein homeostasis and may ensure efficient removal of disease-associated misfolded Eag1 mutant channels.
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Affiliation(s)
- Ya-Ching Fang
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ssu-Ju Fu
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Po-Hao Hsu
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Pei-Tzu Chang
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Jing-Jia Huang
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Chih Chiu
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Yi-Fan Liao
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Guey-Mei Jow
- School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan
| | - Chih-Yung Tang
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | - Chung-Jiuan Jeng
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Brain Research Center, National Yang-Ming University, Taipei, Taiwan.
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16
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Wang H, Lu Y, Wang M, Wu Y, Wang X, Li Y. Roles of E3 ubiquitin ligases in gastric cancer carcinogenesis and their effects on cisplatin resistance. J Mol Med (Berl) 2021; 99:193-212. [PMID: 33392633 DOI: 10.1007/s00109-020-02015-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 11/15/2020] [Accepted: 11/20/2020] [Indexed: 12/28/2022]
Abstract
Although gastric cancer (GC) is one of the most common cancers with high incidence and mortality rates, its pathogenesis is still not elucidated. GC carcinogenesis is complicated and involved in the activation of oncoproteins and inactivation of tumor suppressors. The ubiquitin-proteasome system (UPS) is crucial for protein degradation and regulation of physiological and pathological processes. E3 ubiquitin ligases are pivotal enzymes in UPS, containing various subfamily proteins. Previous studies report that some E3 ligases, including SKP2, CUL1, and MDM2, act as oncoproteins in GC carcinogenesis. On the other hand, FBXW7, FBXL5, FBXO31, RNF43, and RNF180 exert as tumor suppressors in GC carcinogenesis. Moreover, E3 ligases modulate cell growth, cell apoptosis, and cell cycle; thus, it is complicated to confer cisplatin resistance/sensitivity in GC cells. The intrinsic and acquired cisplatin resistance limits its clinical application against GC. In this review, we explore oncogenic and tumor suppressive roles of E3 ligases in GC carcinogenesis and focus on the effects of E3 ligases on cisplatin resistance in GC cells, which will provide novel therapeutic targets for GC therapy, especially for cisplatin-resistant patients.
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Affiliation(s)
- Huizhen Wang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Yida Lu
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Mingliang Wang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Youliang Wu
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Xiaodong Wang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Yongxiang Li
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China.
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17
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Role of CCCH-Type Zinc Finger Proteins in Human Adenovirus Infections. Viruses 2020; 12:v12111322. [PMID: 33217981 PMCID: PMC7698620 DOI: 10.3390/v12111322] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/14/2020] [Accepted: 11/16/2020] [Indexed: 02/08/2023] Open
Abstract
The zinc finger proteins make up a significant part of the proteome and perform a huge variety of functions in the cell. The CCCH-type zinc finger proteins have gained attention due to their unusual ability to interact with RNA and thereby control different steps of RNA metabolism. Since virus infections interfere with RNA metabolism, dynamic changes in the CCCH-type zinc finger proteins and virus replication are expected to happen. In the present review, we will discuss how three CCCH-type zinc finger proteins, ZC3H11A, MKRN1, and U2AF1, interfere with human adenovirus replication. We will summarize the functions of these three cellular proteins and focus on their potential pro- or anti-viral activities during a lytic human adenovirus infection.
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18
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Jab1 promotes gastric cancer tumorigenesis via non-ubiquitin proteasomal degradation of p14ARF. Gastric Cancer 2020; 23:1003-1017. [PMID: 32458234 DOI: 10.1007/s10120-020-01087-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 05/16/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND Jab1 has been reported to regulate various proteins in signal transduction pathways and be implicated in carcinogenesis or tumor progression. However, the precise role and molecular mechanism of Jab1 in gastric tumorigenesis have not yet been fully elucidated. METHODS Jab1 staining in gastric cancer tissues and paired non-cancerous tissues was measured using tissue microarray (TMA) technology. The impact of Jab1 on tumor growth in vivo was analyzed using xenotransplantation experiments in Balb/c mice. The expression of Jab1 and p14ARF in gastric cancer cells was analyzed by western blot and confocal immunofluorescence. CCK-8 and cell cycle experiment were used to evaluate the cell proliferation. Ubiquitination assay was performed to validate whether ubiquitination is involved in Jab1-mediated p14ARF degradation. RESULTS The expression level of protein p14ARF was inversely correlated with the protein level of Jab1. Then, we investigated the mechanism that how Jab1 induced p14ARF depletion. Mechanistic studies showed that Jab1 induced ubiquitin-independent proteasomal p14ARF degradation in gastric cancer cells. Our data demonstrated that Jab1 protein was a vital upstream negative modulation factor of p14ARF, and Jab1 could promote cell proliferation and tumor growth via inhibiting the expression of p14ARF in vivo and in vitro. Moreover, silencing Jab1 protein expression declined tumor growth and further increased the apoptosis rate of gastric cancer cells. In further studies of gastric cancer specimens, we found the increased level of Jab1 protein shortened the overall survival. CONCLUSION Jab1 is upstream of p14ARF and promote gastric cancer cell proliferation in vitro and in vivo. Furthermore, Jab1 decreased the expression of p14ARF though ubiquitination independent proteasomal degradation. Therefore, the connection of Jab1 and p14ARF may provide new methods for the treatment of gastric cancer.
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19
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Post-Translational Regulation of ARF: Perspective in Cancer. Biomolecules 2020; 10:biom10081143. [PMID: 32759846 PMCID: PMC7465197 DOI: 10.3390/biom10081143] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/25/2020] [Accepted: 07/29/2020] [Indexed: 02/07/2023] Open
Abstract
Tumorigenesis can be induced by various stresses that cause aberrant DNA mutations and unhindered cell proliferation. Under such conditions, normal cells autonomously induce defense mechanisms, thereby stimulating tumor suppressor activation. ARF, encoded by the CDKN2a locus, is one of the most frequently mutated or deleted tumor suppressors in human cancer. The safeguard roles of ARF in tumorigenesis are mainly mediated via the MDM2-p53 axis, which plays a prominent role in tumor suppression. Under normal conditions, low p53 expression is stringently regulated by its target gene, MDM2 E3 ligase, which induces p53 degradation in a ubiquitin-proteasome-dependent manner. Oncogenic signals induced by MYC, RAS, and E2Fs trap MDM2 in the inhibited state by inducing ARF expression as a safeguard measure, thereby activating the tumor-suppressive function of p53. In addition to the MDM2-p53 axis, ARF can also interact with diverse proteins and regulate various cellular functions, such as cellular senescence, apoptosis, and anoikis, in a p53-independent manner. As the evidence indicating ARF as a key tumor suppressor has been accumulated, there is growing evidence that ARF is sophisticatedly fine-tuned by the diverse factors through transcriptional and post-translational regulatory mechanisms. In this review, we mainly focused on how cancer cells employ transcriptional and post-translational regulatory mechanisms to manipulate ARF activities to circumvent the tumor-suppressive function of ARF. We further discussed the clinical implications of ARF in human cancer.
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20
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Wang M, Dai W, Ke Z, Li Y. Functional roles of E3 ubiquitin ligases in gastric cancer. Oncol Lett 2020; 20:22. [PMID: 32774495 PMCID: PMC7405480 DOI: 10.3892/ol.2020.11883] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 04/29/2020] [Indexed: 12/15/2022] Open
Abstract
To date, >650 E3 ubiquitin ligases have been described in humans, including >600 really interesting new genes (RINGs), 28 homologous to E6-associated protein C-terminus (HECTs) and several RING-in-between-RINGs. They are considered key regulators and therapeutic targets of many types of human cancers, including gastric cancer (GC). Among them, some RING and HECT E3 ligases are closely related to the proliferation, infiltration and prognosis of GC. During the past few years, abnormal expressions and functions of many E3 ligases have been identified in GC. However, the functional roles of E3 ligases in GC have not been fully elucidated. The present article focuses on the functional roles of E3 ligases related to the proteasome in GC. In this comprehensive review, the latest research progress on E3 ligases involved in GC and elaborate their structure, classification, functional roles and therapeutic value in GC was summarized. Finally, 30 E3 ligases that serve essential roles in regulating the development of GC were described. Some of these ligases may serve as oncogenes or tumor suppressors in GC, whereas the pathological mechanism of others needs further study; for example, constitutive photomorphogenic 1. In conclusion, the present review demonstrated that E3 ligases are crucial tumor regulatory factors and potential therapeutic targets in GC. Therefore, more studies should focus on the therapeutic targeting of E3 ligases in GC.
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Affiliation(s)
- Mingliang Wang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Wei Dai
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Zhangyan Ke
- Department of Geriatric Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Yongxiang Li
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230032, P.R. China
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21
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Bang S, Kaur S, Kurokawa M. Regulation of the p53 Family Proteins by the Ubiquitin Proteasomal Pathway. Int J Mol Sci 2019; 21:E261. [PMID: 31905981 PMCID: PMC6981958 DOI: 10.3390/ijms21010261] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 12/24/2019] [Indexed: 12/25/2022] Open
Abstract
The tumor suppressor p53 and its homologues, p63 and p73, play a pivotal role in the regulation of the DNA damage response, cellular homeostasis, development, aging, and metabolism. A number of mouse studies have shown that a genetic defect in the p53 family could lead to spontaneous tumor development, embryonic lethality, or severe tissue abnormality, indicating that the activity of the p53 family must be tightly regulated to maintain normal cellular functions. While the p53 family members are regulated at the level of gene expression as well as post-translational modification, they are also controlled at the level of protein stability through the ubiquitin proteasomal pathway. Over the last 20 years, many ubiquitin E3 ligases have been discovered that directly promote protein degradation of p53, p63, and p73 in vitro and in vivo. Here, we provide an overview of such E3 ligases and discuss their roles and functions.
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Affiliation(s)
| | | | - Manabu Kurokawa
- Department of Biological Sciences, Kent State University, Kent, OH 44242, USA; (S.B.); (S.K.)
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22
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Kotla S, Le NT, Vu HT, Ko KA, Gi YJ, Thomas TN, Giancursio C, Lusis AJ, Cooke JP, Fujiwara K, Abe JI. Endothelial senescence-associated secretory phenotype (SASP) is regulated by Makorin-1 ubiquitin E3 ligase. Metabolism 2019; 100:153962. [PMID: 31476350 PMCID: PMC7059097 DOI: 10.1016/j.metabol.2019.153962] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 08/02/2019] [Accepted: 08/21/2019] [Indexed: 12/23/2022]
Abstract
BACKGROUND Disturbed flow (d-flow)-induced senescence and activation of endothelial cells (ECs) have been suggested to have critical roles in promoting atherosclerosis. Telomeric repeat-binding factor 2 (TERF2)-interacting protein (TERF2IP), a member of the shelterin complex at the telomere, regulates the senescence-associated secretory phenotype (SASP), in which EC activation and senescence are engendered simultaneously by p90RSK-induced phosphorylation of TERF2IP S205 and subsequent nuclear export of the TERF2IP-TERF2 complex. In this study, we investigated TERF2IP-dependent gene expression and its role in regulating d-flow-induced SASP. METHODS A principal component analysis and hierarchical clustering were used to identify genes whose expression is regulated by TERF2IP in ECs under d-flow conditions. Senescence was determined by reduced telomere length, increased p53 and p21 expression, and increased apoptosis; EC activation was detected by NF-κB activation and the expression of adhesion molecules. The involvement of TERF2IP S205 phosphorylation in d-flow-induced SASP was assessed by depletion of TERF2IP and mutation of the phosphorylation site. RESULTS Our unbiased transcriptome analysis showed that TERF2IP caused alteration in the expression of a distinct set of genes, including rapamycin-insensitive companion of mTOR (RICTOR) and makorin-1 (MKRN1) ubiquitin E3 ligase, under d-flow conditions. In particular, both depletion of TERF2IP and overexpression of the TERF2IP S205A phosphorylation site mutant in ECs increased the d-flow and p90RSK-induced MKRN1 expression and subsequently inhibited apoptosis, telomere shortening, and NF-κB activation in ECs via suppression of p53, p21, and telomerase (TERT) induction. CONCLUSIONS MKRN1 and RICTOR belong to a distinct reciprocal gene set that is both negatively and positively regulated by p90RSK. TERF2IP S205 phosphorylation, a downstream event of p90RSK activation, uniquely inhibits MKRN1 expression and contributes to EC activation and senescence, which are key events for atherogenesis.
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Affiliation(s)
- Sivareddy Kotla
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| | - Nhat-Tu Le
- Center for Cardiovascular Regeneration, Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
| | - Hang Thi Vu
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kyung Ae Ko
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Young Jin Gi
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Tamlyn N Thomas
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Carolyn Giancursio
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Aldos J Lusis
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - John P Cooke
- Center for Cardiovascular Regeneration, Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
| | - Keigi Fujiwara
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jun-Ichi Abe
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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23
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Horvat A, Noto JM, Ramatchandirin B, Zaika E, Palrasu M, Wei J, Schneider BG, El-Rifai W, Peek RM, Zaika AI. Helicobacter pylori pathogen regulates p14ARF tumor suppressor and autophagy in gastric epithelial cells. Oncogene 2018; 37:5054-5065. [PMID: 29849123 PMCID: PMC6138561 DOI: 10.1038/s41388-018-0343-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 05/04/2018] [Accepted: 05/06/2018] [Indexed: 12/21/2022]
Abstract
Infection with Helicobacter pylori is one of the strongest risk factors for development of gastric cancer. Although these bacteria infect approximately half of the world's population, only a small fraction of infected individuals develops gastric malignancies. Interactions between host and bacterial virulence factors are complex and interrelated, making it difficult to elucidate specific processes associated with H. pylori-induced tumorigenesis. In this study, we found that H. pylori inhibits p14ARF tumor suppressor by inducing its degradation. This effect was found to be strain-specific. Downregulation of p14ARF induced by H. pylori leads to inhibition of autophagy in a p53-independent manner in infected cells. We identified TRIP12 protein as E3 ubiquitin ligase that is upregulated by H. pylori, inducing ubiquitination and subsequent degradation of p14ARF protein. Using isogenic H. pylori mutants, we found that induction of TRIP12 is mediated by bacterial virulence factor CagA. Increased expression of TRIP12 protein was found in infected gastric epithelial cells in vitro and human gastric mucosa of H. pylori-infected individuals. In conclusion, our data demonstrate a new mechanism of ARF inhibition that may affect host-bacteria interactions and facilitate tumorigenic transformation in the stomach.
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Affiliation(s)
- Andela Horvat
- Department of Surgery, Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, Nashville, TN, USA
| | - Jennifer M Noto
- Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Balamurugan Ramatchandirin
- Department of Surgery, Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, Nashville, TN, USA
| | - Elena Zaika
- Department of Surgery, University of Miami, Miami, FL, USA
| | | | - Jinxiong Wei
- Department of Surgery, Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, Nashville, TN, USA
| | - Barbara G Schneider
- Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Wael El-Rifai
- Department of Surgery, University of Miami, Miami, FL, USA
| | - Richard M Peek
- Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Alexander I Zaika
- Department of Surgery, Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, Nashville, TN, USA.
- Department of Surgery, University of Miami, Miami, FL, USA.
- Department of Veterans Affairs, Miami VA Healthcare System, Miami, FL, USA.
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24
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Lee MS, Han HJ, Han SY, Kim IY, Chae S, Lee CS, Kim SE, Yoon SG, Park JW, Kim JH, Shin S, Jeong M, Ko A, Lee HY, Oh KJ, Lee YH, Bae KH, Koo SH, Kim JW, Seong JK, Hwang D, Song J. Loss of the E3 ubiquitin ligase MKRN1 represses diet-induced metabolic syndrome through AMPK activation. Nat Commun 2018; 9:3404. [PMID: 30143610 PMCID: PMC6109074 DOI: 10.1038/s41467-018-05721-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 07/19/2018] [Indexed: 01/05/2023] Open
Abstract
AMP-activated protein kinase (AMPK) plays a key role in controlling energy metabolism in response to physiological and nutritional status. Although AMPK activation has been proposed as a promising molecular target for treating obesity and its related comorbidities, the use of pharmacological AMPK activators has been met with contradictory therapeutic challenges. Here we show a regulatory mechanism for AMPK through its ubiquitination and degradation by the E3 ubiquitin ligase makorin ring finger protein 1 (MKRN1). MKRN1 depletion promotes glucose consumption and suppresses lipid accumulation due to AMPK stabilisation and activation. Accordingly, MKRN1-null mice show chronic AMPK activation in both liver and adipose tissue, resulting in significant suppression of diet-induced metabolic syndrome. We demonstrate also its therapeutic effect by administering shRNA targeting MKRN1 into obese mice that reverses non-alcoholic fatty liver disease. We suggest that ubiquitin-dependent AMPK degradation represents a target therapeutic strategy for metabolic disorders. AMPK activation has been suggested as treatment for obesity and its complications. Here the authors show that the ubiquitin ligase MKRN1 binds to AMPK and mediates its ubiquitination and degradation. Loss of MKRN1 leads to AMPK activation, increased glucose consumption and decreased lipid accumulation.
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Affiliation(s)
- Min-Sik Lee
- Harvard Medical School, Boston Children's Hospital, 3 Blackfan Circle CLS-16060.2, Boston, MA, 02115, USA
| | - Hyun-Ji Han
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Su Yeon Han
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Il Young Kim
- Laboratory of Developmental Biology and Genomics, Research Institute for Veterinary Science and BK21 Program for Creative Veterinary Science and Research, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Republic of Korea.,Korea Mouse Phenotyping Center (KMPC), Seoul National University, Seoul, 08826, Republic of Korea
| | - Sehyun Chae
- Center for Plant Aging Research, Institute for Basic Science, and Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, 42988, Republic of Korea
| | - Choong-Sil Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Sung Eun Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Seul Gi Yoon
- Korea Mouse Phenotyping Center (KMPC), Seoul National University, Seoul, 08826, Republic of Korea
| | - Jun-Won Park
- Korea Mouse Phenotyping Center (KMPC), Seoul National University, Seoul, 08826, Republic of Korea
| | - Jung-Hoon Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Soyeon Shin
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Manhyung Jeong
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Aram Ko
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Ho-Young Lee
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Kyoung-Jin Oh
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Yun-Hee Lee
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, 21983, Republic of Korea
| | - Kwang-Hee Bae
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Seung-Hoi Koo
- Division of Life Sciences, College of Life Sciences & Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Jea-Woo Kim
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Je Kyung Seong
- Laboratory of Developmental Biology and Genomics, Research Institute for Veterinary Science and BK21 Program for Creative Veterinary Science and Research, College of Veterinary Medicine, Seoul National University, Seoul, 08826, Republic of Korea.,Korea Mouse Phenotyping Center (KMPC), Seoul National University, Seoul, 08826, Republic of Korea
| | - Daehee Hwang
- Center for Plant Aging Research, Institute for Basic Science, and Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, 42988, Republic of Korea
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea.
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25
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Ko A, Han SY, Song J. Regulatory Network of ARF in Cancer Development. Mol Cells 2018; 41:381-389. [PMID: 29665672 PMCID: PMC5974615 DOI: 10.14348/molcells.2018.0100] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 12/21/2022] Open
Abstract
ARF is a tumor suppressor protein that has a pivotal role in the prevention of cancer development through regulating cell proliferation, senescence, and apoptosis. As a factor that induces senescence, the role of ARF as a tumor suppressor is closely linked to the p53-MDM2 axis, which is a key process that restrains tumor formation. Thus, many cancer cells either lack a functional ARF or p53, which enables them to evade cell oncogenic stress-mediated cycle arrest, senescence, or apoptosis. In particular, the ARF gene is a frequent target of genetic and epigenetic alterations including promoter hyper-methylation or gene deletion. However, as many cancer cells still express ARF, pathways that negatively modulate transcriptional or post-translational regulation of ARF could be potentially important means for cancer cells to induce cellular proliferation. These recent findings of regulators affecting ARF protein stability along with its low levels in numerous human cancers indicate the significance of an ARF post-translational mechanism in cancers. Novel findings of regulators stimulating or suppressing ARF function would provide new therapeutic targets to manage cancer- and senescence-related diseases. In this review, we present the current knowledge on the regulation and alterations of ARF expression in human cancers, and indicate the importance of regulators of ARF as a prognostic marker and in potential therapeutic strategies.
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Affiliation(s)
- Aram Ko
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
| | - Su Yeon Han
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722,
Korea
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26
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Porcine MKRN1 Modulates the Replication and Pathogenesis of Porcine Circovirus Type 2 by Inducing Capsid Protein Ubiquitination and Degradation. J Virol 2018. [PMID: 29514908 DOI: 10.1128/jvi.00100-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Porcine circovirus type 2 (PCV2) capsid protein (Cap) is a unique structure protein that plays pivotal roles in the process of viral replication and pathogenesis. Herein, we characterized a putative porcine Makorin RING finger protein 1 (pMKRN1) variant, an N-terminal-truncated variant of putative full-size porcine MKRN1 which has a unique expression pattern resulting from the porcine mkrn1 gene and which interacts with PCV2 Cap. A domain mapping assay showed that the C terminus of pMKRN1 and fragments (amino acids 108 to 198) of Cap are required for this interaction. PCV2 transiently upregulated pMKRN1 in PK-15 cells, but persistent viral infection downregulated pMKRN1 in major pathological tissues of PCV2-infected piglets. Overexpression of pMKRN1 significantly inhibited the generation of progeny PCV2 via ubiquitination and degradation of Cap, whereas knockout of pMKRN1 blocked Cap degradation and promoted progeny virus replication. pMKRN1 specifically targeted PCV2 Cap lysine residues 164, 179, and 191 to induce polyubiquitination and subsequent degradation. Mutation of either of the three lysine residues in the Cap protein or mutation of the histidine at residue 243 within the RING finger domain of pMKRN1 abrogated the E3 ligase activity of pMKRN1, rendering cells incapable of inducing Cap ubiquitination and degradation. Consistent with this finding, a Cap ubiquitination-deficient PCV2 strain showed enhanced virus replication and produced severe histological lesions in the lung and lymph node tissues compared with wild-type PCV2. Taken together, the results presented here suggest that PCV2 downregulates the pMKRN1 variant to avoid pMKRN1-mediated Cap ubiquitination and degradation, thus promoting viral replication and pathogenesis in its targeted tissues.IMPORTANCE Porcine circovirus type 2 is the pathogen to which pigs are the most susceptible, causing immense economic losses in the global swine industry, but whether host cells have developed some strategies to prevent viral replication is still unclear. Here, we found that porcine MKRN1 (pMKRN1) was upregulated in the early stage of PCV2 infection and mediated the polyubiquitination and degradation of Cap protein to block PCV2 replication, yet persistent PCV2 infection downregulated pMKRN1 levels to avoid degradation, promoting viral replication and pathogenesis in its targeted tissues. These data present new insight into the molecular mechanisms underlying the antiviral effects of pMKRN1 E3 ligase during PCV2 infection and also suggest potential new control measures for PCV2 outbreaks.
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27
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Lee HK, Lee EW, Seo J, Jeong M, Lee SH, Kim SY, Jho EH, Choi CH, Chung JY, Song J. Ubiquitylation and degradation of adenomatous polyposis coli by MKRN1 enhances Wnt/β-catenin signaling. Oncogene 2018; 37:4273-4286. [DOI: 10.1038/s41388-018-0267-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 03/08/2018] [Accepted: 03/27/2018] [Indexed: 12/20/2022]
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28
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Inoue K, Fry EA. Aberrant Expression of p14 ARF in Human Cancers: A New Biomarker? TUMOR & MICROENVIRONMENT 2018; 1:37-44. [PMID: 30740529 PMCID: PMC6364748 DOI: 10.4103/tme.tme_24_17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The ARF and INK4a genes are located on the CDKN2a locus, both showing tumor suppressive activity. ARF has been shown to monitor potentially harmful oncogenic signalings, making early stage cancer cells undergo senescence or programmed cell death to prevent cancer. Conversely, INK4a detects both aging and incipient cancer cell signals, and thus these two gene functions are different. The efficiency of detection of oncogenic signals is more efficient for the for the former than the latter in the mouse system. Both ARF and INK4a genes are inactivated by gene deletion, promoter methylation, frame shift, aberrant splicing although point mutations for the coding region affect only the latter. Recent studies show the splicing alterations that affect only ARF or both ARF and INK4a genes suggesting that ARF is inactivated in human tumors more frequently than what was previously thought. The ARF gene is activated by E2Fs and Dmp1 transcription factors while it is repressed by Bmi1, Tbx2/3, Twist1, and Pokemon nuclear proteins. It is also regulated at protein levels by Arf ubiquitin ligase named ULF, MKRN1, and Siva1. The prognostic value of ARF overexpression is controversial since it is induced in early stage cancer cells to eliminate pre-malignant cells (better prognosis); however, it may also indicate that the tumor cells have mutant p53 associated with worse prognosis. The ARF tumor suppressive protein can be used as a biomarker to detect early stage cancer cells as well as advanced stage tumors with p53 inactivation.
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Affiliation(s)
- Kazushi Inoue
- The Department of Pathology, Wake Forest University Health Sciences, Winston-Salem, NC 27157
| | - Elizabeth A. Fry
- The Department of Pathology, Wake Forest University Health Sciences, Winston-Salem, NC 27157
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29
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Oncogene-induced senescence mediated by c-Myc requires USP10 dependent deubiquitination and stabilization of p14ARF. Cell Death Differ 2018; 25:1050-1062. [PMID: 29472714 DOI: 10.1038/s41418-018-0072-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 01/08/2018] [Accepted: 01/22/2018] [Indexed: 12/21/2022] Open
Abstract
Oncogene-induced senescence (OIS) is a critical tumor-suppressor mechanism, which prevents hyper-proliferation and transformation of cells. c-Myc promotes OIS through the transcriptional activation of p14ARF followed by p53 activation. Although the oncogene-mediated transcriptional regulation of p14ARF has been well addressed, the post-translational modification of p14ARF regulated by oncogenic stress has yet to be investigated. Here, we found that c-Myc increased p14ARF protein stability by inducing the transcription of ubiquitin-specific protease 10 (USP10). USP10, in turn, mediated the deubiquitination of p14ARF, preventing its proteasome-dependent degradation. USP10-null mouse embryonic fibroblasts and human primary cells depleted of USP10 bypassed c-Myc-induced senescence via the destabilization of p14ARF, and these cells displayed accelerated hyper-proliferation and transformation. Clinically the c-Myc-USP10-p14ARF axis was disrupted in non-small cell lung cancer patients, resulting in significantly worse overall survival. Our studies indicate that USP10 induced by c-Myc has a crucial role in OIS by maintaining the stability of key tumor suppressor p14ARF.
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30
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Kim HY, Cho Y, Kang H, Yim YS, Kim SJ, Song J, Chun KH. Targeting the WEE1 kinase as a molecular targeted therapy for gastric cancer. Oncotarget 2018; 7:49902-49916. [PMID: 27363019 PMCID: PMC5226556 DOI: 10.18632/oncotarget.10231] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 05/28/2016] [Indexed: 12/23/2022] Open
Abstract
Wee1 is a member of the Serine/Threonine protein kinase family and is a key regulator of cell cycle progression. It has been known that WEE1 is highly expressed and has oncogenic functions in various cancers, but it is not yet studied in gastric cancers. In this study, we investigated the oncogenic role and therapeutic potency of targeting WEE1 in gastric cancer. At first, higher expression levels of WEE1 with lower survival probability were determined in stage 4 gastric cancer patients or male patients with accompanied lymph node metastasis. To determine the function of WEE1 in gastric cancer cells, we determined that WEE1 ablation decreased the proliferation, migration, and invasion, while overexpression of WEE1 increased these effects in gastric cancer cells. We also validated the clinical application of WEE1 targeting by a small molecule, AZD1775 (MK-1775), which is a WEE1 specific inhibitor undergoing clinical trials. AZD1775 significantly inhibited cell proliferation and induced apoptosis and cell cycle arrest in gastric cancer cells, which was more effective in WEE1 high-expressing gastric cancer cells. Moreover, we performed combination treatments with AZD1775 and anti-cancer agents, 5- fluorouracil or Paclitaxel in gastric cancer cells and in gastric cancer orthotopic-transplanted mice to maximize the therapeutic effect and safety of AZD1775. The combination treatments dramatically inhibited the proliferation of gastric cancer cells and tumor burdens in stomach orthotopic-transplanted mice. Taken together, we propose that WEE1 is over-expressed and could enhance gastric cancer cell proliferation and metastasis. Therefore, we suggest that WEE1 is a potent target for gastric cancer therapy.
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Affiliation(s)
- Hye-Young Kim
- Department of Biochemistry & Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Korea.,Department of Biochemistry, College of Life Science and Biotechnology, Seodaemun-gu, Seoul 03722, Korea
| | - Yunhee Cho
- Department of Biochemistry & Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Korea.,Brain Korea 21 PlusProject for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Korea
| | - HyeokGu Kang
- Department of Biochemistry & Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Korea.,Brain Korea 21 PlusProject for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Korea
| | - Ye-Seal Yim
- Department of Biochemistry & Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Korea.,Brain Korea 21 PlusProject for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Korea
| | - Seok-Jun Kim
- Department of Biochemistry & Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Korea.,Brain Korea 21 PlusProject for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Korea
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Seodaemun-gu, Seoul 03722, Korea
| | - Kyung-Hee Chun
- Department of Biochemistry & Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Korea.,Brain Korea 21 PlusProject for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Korea
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31
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Dong X, Hu X, Chen J, Hu D, Chen LF. BRD4 regulates cellular senescence in gastric cancer cells via E2F/miR-106b/p21 axis. Cell Death Dis 2018; 9:203. [PMID: 29434197 PMCID: PMC5833665 DOI: 10.1038/s41419-017-0181-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/22/2017] [Accepted: 11/24/2017] [Indexed: 12/27/2022]
Abstract
Small molecules targeting bromodomains of BET proteins possess strong anti-tumor activities and have emerged as potential therapeutics for cancer. However, the underlying mechanisms for the anti-proliferative activity of these inhibitors are still not fully characterized. In this study, we demonstrated that BET inhibitor JQ1 suppressed the proliferation and invasiveness of gastric cancer cells by inducing cellular senescence. Depletion of BRD4, which was overexpressed in gastric cancer tissues, but not other BET proteins recapitulated JQ1-induced cellular senescence with increased cellular SA-β-Gal activity and elevated p21 levels. In addition, we showed that the levels of p21 were regulated at the post-transcriptional level by BRD4-dependent expression of miR-106b-5p, which targets the 3'-UTR of p21 mRNA. Overexpression of miR-106b-5p prevented JQ1-induced p21 expression and BRD4 inhibition-associated cellular senescence, whereas miR-106b-5p inhibitor up-regulated p21 and induced cellular senescence. Finally, we demonstrated that inhibition of E2F suppressed the binding of BRD4 to the promoter of miR-106b-5p and inhibited its transcription, leading to the increased p21 levels and cellular senescence in gastric cancer cells. Our results reveal a novel mechanism by which BRD4 regulates cancer cell proliferation by modulating the cellular senescence through E2F/miR-106b-5p/p21 axis and provide new insights into using BET inhibitors as potential anticancer drugs.
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Affiliation(s)
- Xingchen Dong
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Xiangming Hu
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jinjing Chen
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Dan Hu
- Department of Pathology, Fujian Provincial Cancer Hospital, The Affiliated Hospital of Fujian Medical University, Fujian, China, 350108
| | - Lin-Feng Chen
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Institute for Translational Medicine, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, China, 350108.
- Department of Medical Biochemistry, College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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32
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Abstract
Senescence is a durable cell cycle arrest that can be induced in response to various stress factors, such as telomere erosion, DNA damage or the aberrant activation of oncogenes. In addition to its well-established role as a stress response programme, research has revealed important physiological roles of senescence in nondisease settings, such as embryonic development, wound healing, tissue repair and ageing. Senescent cells secrete various cytokines, chemokines, matrix remodelling proteases and growth factors, a phenotype collectively referred to as the senescence-associated secretory phenotype. These factors evoke immune responses that, depending on the pathophysiological context, can either prevent or even fuel disease and tumorigenesis. Remarkably, even the gut microbiota can influence senescence in various organs. In this Review, we provide an introduction to cellular senescence, addressed particularly to gastroenterologists and hepatologists, and discuss the implications of senescence for the pathogenesis of malignant and nonmalignant gastrointestinal and hepatobiliary diseases. We conclude with an outlook on how modulation of cellular senescence might be used for therapeutic purposes.
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33
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Human Adenovirus Infection Causes Cellular E3 Ubiquitin Ligase MKRN1 Degradation Involving the Viral Core Protein pVII. J Virol 2018; 92:JVI.01154-17. [PMID: 29142133 DOI: 10.1128/jvi.01154-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 11/12/2017] [Indexed: 11/20/2022] Open
Abstract
Human adenoviruses (HAdVs) are common human pathogens encoding a highly abundant histone-like core protein, VII, which is involved in nuclear delivery and protection of viral DNA as well as in sequestering immune danger signals in infected cells. The molecular details of how protein VII acts as a multifunctional protein have remained to a large extent enigmatic. Here we report the identification of several cellular proteins interacting with the precursor pVII protein. We show that the cellular E3 ubiquitin ligase MKRN1 is a novel precursor pVII-interacting protein in HAdV-C5-infected cells. Surprisingly, the endogenous MKRN1 protein underwent proteasomal degradation during the late phase of HAdV-C5 infection in various human cell lines. MKRN1 protein degradation occurred independently of the HAdV E1B55K and E4orf6 proteins. We provide experimental evidence that the precursor pVII protein binding enhances MKRN1 self-ubiquitination, whereas the processed mature VII protein is deficient in this function. Based on these data, we propose that the pVII protein binding promotes MKRN1 self-ubiquitination, followed by proteasomal degradation of the MKRN1 protein, in HAdV-C5-infected cells. In addition, we show that measles virus and vesicular stomatitis virus infections reduce the MKRN1 protein accumulation in the recipient cells. Taken together, our results expand the functional repertoire of the HAdV-C5 precursor pVII protein in lytic virus infection and highlight MKRN1 as a potential common target during different virus infections.IMPORTANCE Human adenoviruses (HAdVs) are common pathogens causing a wide range of diseases. To achieve pathogenicity, HAdVs have to counteract a variety of host cell antiviral defense systems, which would otherwise hamper virus replication. In this study, we show that the HAdV-C5 histone-like core protein pVII binds to and promotes self-ubiquitination of a cellular E3 ubiquitin ligase named MKRN1. This mutual interaction between the pVII and MKRN1 proteins may prime MKRN1 for proteasomal degradation, because the MKRN1 protein is efficiently degraded during the late phase of HAdV-C5 infection. Since MKRN1 protein accumulation is also reduced in measles virus- and vesicular stomatitis virus-infected cells, our results signify the general strategy of viruses to target MKRN1.
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34
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Ko A, Han SY, Song J. Dynamics of ARF regulation that control senescence and cancer. BMB Rep 2017; 49:598-606. [PMID: 27470213 PMCID: PMC5346319 DOI: 10.5483/bmbrep.2016.49.11.120] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Indexed: 12/16/2022] Open
Abstract
ARF is an alternative reading frame product of the INK4a/ARF locus, inactivated in numerous human cancers. ARF is a key regulator of cellular senescence, an irreversible cell growth arrest that suppresses tumor cell growth. It functions by sequestering MDM2 (a p53 E3 ligase) in the nucleolus, thus activating p53. Besides MDM2, ARF has numerous other interacting partners that induce either cellular senescence or apoptosis in a p53-independent manner. This further complicates the dynamics of the ARF network. Expression of ARF is frequently disrupted in human cancers, mainly due to epigenetic and transcriptional regulation. Vigorous studies on various transcription factors that either positively or negatively regulate ARF transcription have been carried out. However, recent focus on posttranslational modifications, particularly ubiquitination, indicates wider dynamic controls of ARF than previously known. In this review, we discuss the role and dynamic regulation of ARF in senescence and cancer.
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Affiliation(s)
- Aram Ko
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Su Yeon Han
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
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35
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Deficiency of Mkrn2 causes abnormal spermiogenesis and spermiation, and impairs male fertility. Sci Rep 2016; 6:39318. [PMID: 28008940 PMCID: PMC5180214 DOI: 10.1038/srep39318] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 11/14/2016] [Indexed: 11/12/2022] Open
Abstract
Although recent studies have shed insights on some of the potential causes of male infertility, new underlining molecular mechanisms still remain to be elucidated. Makorin-2 (Mkrn2) is an evolutionarily conserved gene whose biological functions are not fully known. We developed an Mrkn2 knockout mouse model to study the role of this gene, and found that deletion of Mkrn2 in mice led to male infertility. Mkrn2 knockout mice produced abnormal sperms characterized by low number, poor motility, and aberrant morphology. Disruption of Mkrn2 also caused failure of sperm release (spermiation failure) and misarrangement of ectoplasmic specialization (ES) in testes, thus impairing spermiogenesis and spermiation. To understand the molecular mechanism, we found that expression of Odf2, a vital protein in spermatogenesis, was significantly decreased. In addition, we found that expression levels of Odf2 were decreased in Mkrn2 knockout mice. We also found that MKRN2 was prominently expressed in the sperm of normal men, but was significantly reduced in infertile men. This result indicates that our finding is clinically relevant. The results of our study provided insights into a new mechanism of male infertility caused by the MKRN2 downregulation.
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36
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Han SY, Ko A, Kitano H, Choi CH, Lee MS, Seo J, Fukuoka J, Kim SY, Hewitt SM, Chung JY, Song J. Molecular Chaperone HSP90 Is Necessary to Prevent Cellular Senescence via Lysosomal Degradation of p14ARF. Cancer Res 2016; 77:343-354. [PMID: 27793846 DOI: 10.1158/0008-5472.can-16-0613] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 09/13/2016] [Accepted: 10/01/2016] [Indexed: 01/09/2023]
Abstract
The tumor suppressor function of p14ARF is regulated at a posttranslational level via mechanisms yet to be fully understood. Here, we report the identification of an unconventional p14ARF degradation pathway induced by the chaperone HSP90 in association with the E3 ubiquitin ligase C-terminus of HSP70-interacting protein (CHIP). The ternary complex of HSP90, CHIP, and p14ARF was required to induce the lysosomal degradation of p14ARF by an ubiquitination-independent but LAMP2A-dependent mechanism. Depletion of HSP90 or CHIP induced p14ARF-dependent senescence in human fibroblasts. Premature senescence observed in cells genetically deficient in CHIP was rescued in cells that were doubly deficient in CHIP and p14ARF. Notably, non-small cell lung cancer cells (NSCLC) positive for p14ARF were sensitive to treatment with the HSP90 inhibitor geldanamycin. Furthermore, overexpression of HSP90 and CHIP with a concomitant loss of p14ARF correlated with poor prognosis in patients with NSCLC. Our findings identify a relationship between p14ARF and its chaperones that suggest new therapeutic strategies in cancers that overexpress HSP90. Cancer Res; 77(2); 343-54. ©2016 AACR.
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Affiliation(s)
- Su Yeon Han
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea (South)
| | - Aram Ko
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea (South)
| | - Haruhisa Kitano
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland.,Department of Thoracic Surgery, Shiga University of Medical Science, Otsu, Japan
| | - Chel Hun Choi
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland.,Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea (South)
| | - Min-Sik Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea (South)
| | - Jinho Seo
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea (South)
| | - Junya Fukuoka
- Department of Pathology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Soo-Youl Kim
- Cancer Cell and Molecular Biology Branch, Division of Cancer Biology, Research Institute, National Cancer Center, Goyang, Republic of Korea (South)
| | - Stephen M Hewitt
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland
| | - Joon-Yong Chung
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea (South).
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37
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La SH, Kim SJ, Kang HG, Lee HW, Chun KH. Ablation of human telomerase reverse transcriptase (hTERT) induces cellular senescence in gastric cancer through a galectin-3 dependent mechanism. Oncotarget 2016; 7:57117-57130. [PMID: 27494887 PMCID: PMC5302977 DOI: 10.18632/oncotarget.10986] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/19/2016] [Indexed: 12/20/2022] Open
Abstract
The human Telomerase Reverse Transcriptase (hTERT) gene encodes a rate-limiting catalytic subunit of telomerase that maintains genomic integrity. Suppression of hTERT expression could induce cellular senescence and is considered a potent approach for gastric cancer therapy. However, control of hTERT expression and function remains poorly understood in gastric cancer. In this study, we demonstrated that high expression levels of hTERT in malignant tissues are correlated with poor survival probability in gastric cancer patients. Knockdown of hTERT expression retarded cell proliferation and cellular senescence, which was confirmed by increased protein expression levels of p21cip1 and p27kip1, and decreased phosphorylation of Rb. In contrast, overexpression of hTERT increased cell proliferation and decreased cellular senescence. Remarkably, the down-regulation of hTERT expression was detected in lgals3-/- mouse embryo fibroblasts (MEFs). Knockdown of galectin-3 decreased the expression of hTERT in gastric cancer cells. Galectin-3 ablation-induced cellular senescence was rescued by concomitant overexpression of hTERT. hTERT ablation-induced cellular senescence and p21cip1 and p27kip1 expression was rescued by concomitant overexpression of galectin-3. The size of tumor burdens was increased in hTERT-overexpressed gastric cancer cells xenografted mice, whereas it was repressed by concomitant depletion of galectin-3. Additionally, we determined that the N-terminal domain of galectin-3 directly interacted with hTERT. The telomeric activity of hTERT was also decreased by galectin-3 ablation. Taken together, ablation of hTERT induces cellular senescence and inhibits the growth of gastric cancer cells, suggesting that it could be a potent target in gastric cancer therapy. We also propose that galectin-3 is an important regulator of hTERT expression and telomeric activity in gastric tumorigenesis.
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Affiliation(s)
- Sun-Hyuk La
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Republic of Korea
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Seok-Jun Kim
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Hyeok-Gu Kang
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Han-Woong Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Kyung-Hee Chun
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seodaemun-gu, Seoul 03722, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seodaemun-gu, Seoul 03722, Republic of Korea
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38
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Zhong JL, Huang CZ. Ubiquitin proteasome system research in gastrointestinal cancer. World J Gastrointest Oncol 2016; 8:198-206. [PMID: 26909134 PMCID: PMC4753170 DOI: 10.4251/wjgo.v8.i2.198] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 10/25/2015] [Accepted: 11/17/2015] [Indexed: 02/05/2023] Open
Abstract
The ubiquitin proteasome system (UPS) is important for the degradation of proteins in eukaryotic cells. It is involved in nearly every cellular process and plays an important role in maintaining body homeostasis. An increasing body of evidence has linked alterations in the UPS to gastrointestinal malignancies, including esophageal, gastric and colorectal cancers. Here, we summarize the current literature detailing the involvement of the UPS in gastrointestinal cancer, highlighting its role in tumor occurrence and development, providing information for therapeutic targets research and anti-gastrointestinal tumor drug design.
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39
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Herrera RA, Kiontke K, Fitch DHA. Makorin ortholog LEP-2 regulates LIN-28 stability to promote the juvenile-to-adult transition in Caenorhabditis elegans. Development 2016; 143:799-809. [PMID: 26811380 DOI: 10.1242/dev.132738] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/16/2016] [Indexed: 12/27/2022]
Abstract
The heterochronic genes lin-28, let-7 and lin-41 regulate fundamental developmental transitions in animals, such as stemness versus differentiation and juvenile versus adult states. We identify a new heterochronic gene, lep-2, in Caenorhabditis elegans. Mutations in lep-2 cause a delay in the juvenile-to-adult transition, with adult males retaining pointed, juvenile tail tips, and displaying defective sexual behaviors. In both sexes, lep-2 mutants fail to cease molting or produce an adult cuticle. We find that LEP-2 post-translationally regulates LIN-28 by promoting LIN-28 protein degradation. lep-2 encodes the sole C. elegans ortholog of the Makorin (Mkrn) family of proteins. Like lin-28 and other heterochronic pathway members, vertebrate Mkrns are involved in developmental switches, including the timing of pubertal onset in humans. Based on shared roles, conservation and the interaction between lep-2 and lin-28 shown here, we propose that Mkrns, together with other heterochronic genes, constitute an evolutionarily ancient conserved module regulating switches in development.
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Affiliation(s)
| | - Karin Kiontke
- Department of Biology, New York University, New York, NY 10003, USA
| | - David H A Fitch
- Department of Biology, New York University, New York, NY 10003, USA Faculty of Arts and Sciences, New York University-Shanghai, Shanghai 200122, China
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40
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Lee HW, Jang KSB, Choi HJ, Jo A, Cheong JH, Chun KH. Celastrol inhibits gastric cancer growth by induction of apoptosis and autophagy. BMB Rep 2015; 47:697-702. [PMID: 24667175 PMCID: PMC4345515 DOI: 10.5483/bmbrep.2014.47.12.069] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Indexed: 01/25/2023] Open
Abstract
Recently, the interest in natural products for the treatment of cancer is increasing because they are the pre-screened candidates. In the present study, we demonstrate the therapeutic effect of celastrol, a triterpene extracted from the root bark of Chinese medicine on gastric cancer. The proliferation of AGS and YCC-2 cells were most sensitively decreased in six kinds of gastric cancer cell lines after the treatment with celastrol. Celastrol inhibited the cell migration and increased G1 arrest in cell-cycle populations in both cell lines. The treatment with celastrol significantly induced autophagy and apoptosis and increased the expression of autophagy and apoptosis-related proteins. We also found an increase in phosphorylated AMPK following a decrease in all phosphorylated forms of AKT, mTOR and S6K after the treatment with celastrol. Moreover, gastric tumor burdens were reduced in a dose-dependent manner by celastrol administration in a xenografted mice model. Taken together, celastrol distinctly inhibits the gastric cancer cell proliferation and induces autophagy and apoptosis. [BMB Reports 2014; 47(12): 697-702]
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Affiliation(s)
- Hyun-Woo Lee
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul 120-752; Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Kenny Seung Bin Jang
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul 120-752; Asia Pacific International School, Seoul 139-852, Korea
| | - Hye Ji Choi
- Department of Surgery, Yonsei University College of Medicine, Seoul 120-752; Brain Korea 21 Plus Project for Medical Sciences, Severance Medical Research Institute, Seoul 120-752, Republic of Korea
| | - Ara Jo
- Department of Surgery, Yonsei University College of Medicine, Seoul 120-752; Brain Korea 21 Plus Project for Medical Sciences, Severance Medical Research Institute, Seoul 120-752, Republic of Korea
| | - Jae-Ho Cheong
- Department of Surgery, Yonsei University College of Medicine, Seoul 120-752, Brain Korea 21 Plus Project for Medical Sciences, Severance Medical Research Institute, Seoul 120-752, Republic of Korea
| | - Kyung-Hee Chun
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul 120-752; Brain Korea 21 Plus Project for Medical Sciences, Severance Medical Research Institute, Seoul 120-752, Republic of Korea
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41
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Cassar PA, Carpenedo RL, Samavarchi-Tehrani P, Olsen JB, Park CJ, Chang WY, Chen Z, Choey C, Delaney S, Guo H, Guo H, Tanner RM, Perkins TJ, Tenenbaum SA, Emili A, Wrana JL, Gibbings D, Stanford WL. Integrative genomics positions MKRN1 as a novel ribonucleoprotein within the embryonic stem cell gene regulatory network. EMBO Rep 2015; 16:1334-57. [PMID: 26265008 PMCID: PMC4670460 DOI: 10.15252/embr.201540974] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 07/15/2015] [Indexed: 02/04/2023] Open
Abstract
In embryonic stem cells (ESCs), gene regulatory networks (GRNs) coordinate gene expression to maintain ESC identity; however, the complete repertoire of factors regulating the ESC state is not fully understood. Our previous temporal microarray analysis of ESC commitment identified the E3 ubiquitin ligase protein Makorin‐1 (MKRN1) as a potential novel component of the ESC GRN. Here, using multilayered systems‐level analyses, we compiled a MKRN1‐centered interactome in undifferentiated ESCs at the proteomic and ribonomic level. Proteomic analyses in undifferentiated ESCs revealed that MKRN1 associates with RNA‐binding proteins, and ensuing RIP‐chip analysis determined that MKRN1 associates with mRNAs encoding functionally related proteins including proteins that function during cellular stress. Subsequent biological validation identified MKRN1 as a novel stress granule‐resident protein, although MKRN1 is not required for stress granule formation, or survival of unstressed ESCs. Thus, our unbiased systems‐level analyses support a role for the E3 ligase MKRN1 as a ribonucleoprotein within the ESC GRN.
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Affiliation(s)
- Paul A Cassar
- Institute of Medical Science University of Toronto, Toronto, ON, Canada Collaborative Program in Genome Biology and Bioinformatics, University of Toronto, Toronto, ON, Canada
| | - Richard L Carpenedo
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | | | - Jonathan B Olsen
- Collaborative Program in Genome Biology and Bioinformatics, University of Toronto, Toronto, ON, Canada Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Chang Jun Park
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Wing Y Chang
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Zhaoyi Chen
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Chandarong Choey
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Sean Delaney
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Huishan Guo
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Hongbo Guo
- Banting and Best Department of Medical Research, Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - R Matthew Tanner
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Theodore J Perkins
- Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Scott A Tenenbaum
- Colleges of Nanoscale Science & Engineering SUNY Polytechnic Institute, Albany, NY, USA
| | - Andrew Emili
- Collaborative Program in Genome Biology and Bioinformatics, University of Toronto, Toronto, ON, Canada Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada Banting and Best Department of Medical Research, Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Jeffrey L Wrana
- Collaborative Program in Genome Biology and Bioinformatics, University of Toronto, Toronto, ON, Canada Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada Center for Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada
| | - Derrick Gibbings
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, ON, Canada
| | - William L Stanford
- Institute of Medical Science University of Toronto, Toronto, ON, Canada Collaborative Program in Genome Biology and Bioinformatics, University of Toronto, Toronto, ON, Canada Sprott Centre for Stem Cell Research, Ottawa Hospital Research Institute, Ottawa, ON, Canada Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, ON, Canada Ottawa Institute of Systems Biology, Ottawa, ON, Canada
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42
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Lee MS, Jeong MH, Lee HW, Han HJ, Ko A, Hewitt SM, Kim JH, Chun KH, Chung JY, Lee C, Cho H, Song J. PI3K/AKT activation induces PTEN ubiquitination and destabilization accelerating tumourigenesis. Nat Commun 2015; 6:7769. [PMID: 26183061 PMCID: PMC4518267 DOI: 10.1038/ncomms8769] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Accepted: 06/08/2015] [Indexed: 12/16/2022] Open
Abstract
The activity of the phosphatase and tensin homologue (PTEN) is known to be suppressed via post-translational modification. However, the mechanism and physiological significance by which post-translational modifications lead to PTEN suppression remain unclear. Here we demonstrate that PTEN destabilization is induced by EGFR- or oncogenic PI3K mutation-mediated AKT activation in cervical cancer. EGFR/PI3K/AKT-mediated ubiquitination and degradation of PTEN are dependent on the MKRN1 E3 ligase. These processes require the stabilization of MKRN1 via AKT-mediated phosphorylation. In cervical cancer patients with high levels of pAKT and MKRN1 expression, PTEN protein levels are low and correlate with a low 5-year survival rate. Taken together, our results demonstrate that PI3K/AKT signals enforce positive-feedback regulation by suppressing PTEN function. Mutations and post-translational modifications of the PI3K/AKT pathway inhibitor PTEN are a feature of many cancers, but these have not been associated with cervical cancer. Here, the authors identify a PI3K/AKT-mediated ubiquitination degradation pathway of PTEN that occurs in patients with cervical cancer.
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Affiliation(s)
- Min-Sik Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Man-Hyung Jeong
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Hyun-Woo Lee
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Hyun-Ji Han
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Aram Ko
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Stephen M Hewitt
- Experimental Pathology Laboratory, Center for Cancer Research, National Cancer Institute, NIH MSC 1500, Bethesda, Maryland 20892, USA
| | - Jae-Hoon Kim
- 1] Department of Obstetrics and Gynecology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 135-720, Republic of Korea [2] Institute of Women's Life Medical Science, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Kyung-Hee Chun
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Joon-Yong Chung
- Experimental Pathology Laboratory, Center for Cancer Research, National Cancer Institute, NIH MSC 1500, Bethesda, Maryland 20892, USA
| | - Cheolju Lee
- BRI, Korea Institute of Science and Technology, Seoul 136-791, Korea
| | - Hanbyoul Cho
- 1] Department of Obstetrics and Gynecology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 135-720, Republic of Korea [2] Institute of Women's Life Medical Science, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
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Lee HW, Kim SJ, Choi IJ, Song J, Chun KH. Targeting Notch signaling by γ-secretase inhibitor I enhances the cytotoxic effect of 5-FU in gastric cancer. Clin Exp Metastasis 2015; 32:593-603. [PMID: 26134677 DOI: 10.1007/s10585-015-9730-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 06/17/2015] [Indexed: 12/17/2022]
Abstract
Current medication for gastric cancer patients has a low success rate and the patients develop rapid tolerance to these drugs. Therefore, the development of new regimens is desired. In this study, we determined that Notch-signaling-related genes were overexpressed and activated in gastric cancer patients and gastric cancer cell lines. According to recent studies, γ-secretase inhibitors (GSIs), which function as Notch signaling inhibitors, could be used as therapeutic drugs in cancer. We demonstrated that GSI I (cbz-IL-CHO) is the most effective GSI in gastric cancer cells. We also determined the cell survival signaling-related proteins that were affected by GSI I. The levels of phosphorylated AKT were significantly decreased upon GSI I treatment, and constitutively activated myristoylated AKT completely blocked GSI I-induced apoptosis and cell survival, suggesting that inhibition of AKT signaling is critical for GSI I-mediated effects in gastric cancer cells. In order to maximize the effects and safety of GSI I, a combination treatment with GSI I and 5-FU was performed. Inhibition of gastric cancer cell proliferation with the combination treatment was significantly better than that with the single treatment. All phosphorylated forms of AKT, p44/42, JNK, and p38 were drastically changed by the combination treatment. Orthotopically transplanted gastric tumor burdens in mice were reduced using the combined treatment. The outcomes of this study clearly demonstrated the therapeutic potential of GSI I in gastric cancer, as well as the greater efficacy of the combined treatment of GSI I with 5-FU. Therefore, we suggest that further clinical trials examining the potential of combined GSI I and 5-FU treatment in gastric cancer patients be undertaken.
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Affiliation(s)
- Hyun-Woo Lee
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, Republic of Korea
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Kim SJ, Lee HW, Baek JH, Cho YH, Kang HG, Jeong JS, Song J, Park HS, Chun KH. Activation of nuclear PTEN by inhibition of Notch signaling induces G2/M cell cycle arrest in gastric cancer. Oncogene 2015; 35:251-60. [DOI: 10.1038/onc.2015.80] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/25/2014] [Accepted: 02/16/2015] [Indexed: 12/19/2022]
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Choi SW, Song JK, Yim YS, Yun HG, Chun KH. Glucose deprivation triggers protein kinase C-dependent β-catenin proteasomal degradation. J Biol Chem 2015; 290:9863-73. [PMID: 25691573 PMCID: PMC4392283 DOI: 10.1074/jbc.m114.606756] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Indexed: 11/07/2022] Open
Abstract
Autophagy is a conserved process that contributes to cell homeostasis. It is well known that induction mainly occurs in response to nutrient starvation, such as starvation of amino acids and insulin, and its mechanisms have been extensively characterized. However, the mechanisms behind cellular glucose deprivation-induced autophagy are as of now poorly understood. In the present study, we determined a mechanism by which glucose deprivation induced the PKC-dependent proteasomal degradation of β-catenin, leading to autophagy. Glucose deprivation was shown to cause a sub-G1 transition and enhancement of the LC3-II protein levels, whereas β-catenin protein underwent degradation in a proteasome-dependent manner. Moreover, the inhibition of GSK3β was unable to abolish the glucose deprivation-mediated β-catenin degradation or up-regulation of LC3-II protein levels, which suggested GSK3β-independent protein degradation. Intriguingly, the inhibition of PKCα using a pharmacological inhibitor and transfection of siRNA for PKCα was observed to effectively block glucose deprivation-induced β-catenin degradation as well as the increase in LC3-II levels and the accumulation of a sub-G1 population. Together, our results demonstrated a molecular mechanism by which glucose deprivation can induce the GSK3β-independent protein degradation of β-catenin, leading to autophagy.
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Affiliation(s)
- Seung-Won Choi
- From the Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea and
| | - Jun-Kyu Song
- From the Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea and the Brain Korea 21 Plus Project for Medical Science, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea
| | - Ye-Seal Yim
- From the Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea and the Brain Korea 21 Plus Project for Medical Science, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea
| | - Ho-Geun Yun
- From the Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea and the Brain Korea 21 Plus Project for Medical Science, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea
| | - Kyung-Hee Chun
- From the Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea and the Brain Korea 21 Plus Project for Medical Science, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea
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Kim SJ, Wang YG, Lee HW, Kang HG, La SH, Choi IJ, Irimura T, Ro JY, Bresalier RS, Chun KH. Up-regulation of neogenin-1 increases cell proliferation and motility in gastric cancer. Oncotarget 2015; 5:3386-98. [PMID: 24930499 PMCID: PMC4102817 DOI: 10.18632/oncotarget.1960] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Although elevated expression of neogenin-1 has been detected in human gastric cancer tissue, its role in gastric tumorigenesis remains unclear due to the lack of neogenin-1 studies in cancer. Therefore, we demonstrated here the function and regulatory mechanism of neogenin-1 in gastric cancer. Neogenin-1 ablation decreased proliferation and migration of gastric cancer cells, whereas its over-expression reversed these effects. Xenografted analyses using gastric cancer cells displayed statistically significant inhibition of tumor growth by neogenin-1 depletion. Interestingly, galectin-3 interacted with HSF-1 directly, which facilitated nuclear-localization and binding on neogenin-1 promoter to drive its transcription and gastric cancer cell motility. The galectin-3-increased gastric cancer cell motility was down-regulated by HSF-1 depletion. Moreover, the parallel expression patterns of galectin-3 and neogenin-1, as well as those of HSF-1 and neogenin-1, were detected in the malignant tissues of gastric cancer patients. Taken together, high-expression of neogenin-1 promotes gastric cancer proliferation and motility and its expression is regulated by HSF-1 and galectin-3 interaction. In addition, we propose further studies for neogenin-1 and its associated pathways to provide them as a proper target for gastric cancer therapy.
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Affiliation(s)
- Seok-Jun Kim
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea
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Hou YC, Deng JY. Role of E3 ubiquitin ligases in gastric cancer. World J Gastroenterol 2015; 21:786-93. [PMID: 25624711 PMCID: PMC4299330 DOI: 10.3748/wjg.v21.i3.786] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/01/2014] [Accepted: 12/01/2014] [Indexed: 02/07/2023] Open
Abstract
E3 ubiquitin ligases have an important role in carcinogenesis and include a large family of proteins that catalyze the ubiquitination of many protein substrates for targeted degradation by the 26S proteasome. So far, E3 ubiquitin ligases have been reported to have a role in a variety of biological processes including cell cycle regulation, cell proliferation, and apoptosis. Recently, several kinds of E3 ubiquitin ligases were demonstrated to be generally highly expressed in gastric cancer (GC) tissues and to contribute to carcinogenesis. In this review, we summarize the current knowledge and information about the clinical significance of E3 ubiquitin ligases in GC. Bortezomib, a proteasome inhibitor, encouraged the evaluation of other components of the ubiquitin proteasome system for pharmaceutical intervention. The clinical value of novel treatment strategies targeting aberrant E3 ubiquitin ligases for GC are discussed in the review.
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48
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Kim SJ, Hwang JA, Ro JY, Lee YS, Chun KH. Galectin-7 is epigenetically-regulated tumor suppressor in gastric cancer. Oncotarget 2014; 4:1461-71. [PMID: 23985992 PMCID: PMC3824540 DOI: 10.18632/oncotarget.1219] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Gastric cancer is the second leading cause of cancer death and remains a major clinical challenge due to poor prognosis and limited treatment options. Therefore, the basic mechanisms underlying gastric tumorigenesis deserve investigation. Although regulation of the galactoside-binding lectin galectin-7 in cancer has been studied, its role in tumor formation and progression remains controversial. In this study, we investigated galectin-7 expression and its role in gastric cancer. Immunohistochemical staining using a tissue microarray of gastric cancer patients revealed significantly low expression levels of galectin-7 in malignant tissues compared with matched normal tissues, and decreased expression of galectin-7 in malignant tissues was associated with advanced TMN stage disease (p =0.034). Importantly, low expression of galectin-7 in normal tissues was associated with a poor survival rate (p =0.0561). Over-expression of galectin-7 in AGS gastric adenocarcinoma cells suppressed cell proliferation, migration, and invasion, whereas ablation of galectin-7 in KATO III gastric carcinoma cells reversed these properties. AGS cells that overexpressed galectin-7 could not form gastric tumors in xenografted mice. More than 70% hypermethylation was observed in 7 of 9 gastric cancer cell lines tested and 5-aza-cytidine treatment lowered galectin-7 expression by reducing methylation in 24 cancer cell lines from five different organ origins. We analyzed CpG islands in the galectin-7 genomic region and detected hypermethylation at +1566bp of exon 2, the predicted p53 binding region. DNA hypermethylation of this region was also detected in gastric cancer tissues from 20 patients. Taken together, our data indicate that galectin-7 has a tumor suppressive function, and that the gene is epigenetically modified by DNA methylation and significantly down-regulated in gastric cancer. Further study of galectin-7 regulation may lead to improved gastric cancer diagnosis and therapy.
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Affiliation(s)
- Seok-Jun Kim
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, Republic of Korea
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Kim SJ, Lee HW, Gu Kang H, La SH, Choi IJ, Ro JY, Bresalier RS, Song J, Chun KH. Ablation of galectin-3 induces p27(KIP1)-dependent premature senescence without oncogenic stress. Cell Death Differ 2014; 21:1769-79. [PMID: 24971481 PMCID: PMC4211374 DOI: 10.1038/cdd.2014.88] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Revised: 05/14/2014] [Accepted: 05/19/2014] [Indexed: 12/20/2022] Open
Abstract
Premature senescence induced by oncogenic stimuli or tumor suppressor activation plays opposing roles in tumorigenesis. Here, we propose that galectin-3, a β-galactoside-binding lectin, regulates premature senescence without oncogenic stress. We detected premature senescence, decreased Skp2, and increased p27KIP1 expression in galectin-3 knockout MEFs and galectin-3-depleted gastric cancer cells. Interestingly, galectin-3 depletion did not affect other senescence inducers such as p14ARF, p16INK4A, and p21WAF1/CIP1, suggesting that galectin-3-regulated senescence is p27KIP1 dependent. We demonstrate that galectin-3 depletion decreases retinoblastoma protein (Rb) phosphorylation (Ser780, Ser807/811), cyclin D1 and CDK4 expression, and E2F1 transcriptional activation. Galectin-3 directly interacts with the cyclin D1/CDK4 complex and promotes hyperphosphorylation of Rb. It also blocks the inhibition of E2F1 transcription, thereby increasing the expression of Skp2 and reducing the stability of p27KIP1 to promote the proliferation of gastric cancer cells. Xenograft mice with galectin-3-depleted gastric cancer cells display tumor growth retardation that is reversed by Skp2 overexpression. Increased expression of galectin-3 is also associated with the advanced TNM (tumor, lymph node, metastasis) system, clinicopathological stage, and lymph node metastases. The probability of survival was significantly decreased in gastric cancer patients with galectin-3high p27KIP1-lowcells. Taken together, our results show that galectin-3 may accelerate gastric tumorigenesis by inhibiting premature senescence.
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Affiliation(s)
- S-J Kim
- 1] Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea [2] Brain Korea 21 Plus Project for Medical Science, Yonsei University, Seoul, Republic of Korea
| | - H-W Lee
- 1] Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea [2] Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - H Gu Kang
- 1] Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea [2] Brain Korea 21 Plus Project for Medical Science, Yonsei University, Seoul, Republic of Korea
| | - S-H La
- 1] Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea [2] Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Il Ju Choi
- Center for Gastric Cancer, National Cancer Center Research Institute, Goyang, Republic of Korea
| | - J Y Ro
- The Methodist Hospital, Department of Pathology and Genomic Medicine, Weill Medical College of Cornell University, Houston, TX, USA
| | - R S Bresalier
- Department of Gastroenterology, Hepatology, and Nutrition, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | - J Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - K-H Chun
- 1] Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea [2] Brain Korea 21 Plus Project for Medical Science, Yonsei University, Seoul, Republic of Korea
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Ubiquitous expression of MAKORIN-2 in normal and malignant hematopoietic cells and its growth promoting activity. PLoS One 2014; 9:e92706. [PMID: 24675897 PMCID: PMC3968021 DOI: 10.1371/journal.pone.0092706] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 02/25/2014] [Indexed: 11/19/2022] Open
Abstract
Makorin-2 (MKRN2) is a highly conserved protein and yet its functions are largely unknown. We investigated the expression levels of MKRN2 and RAF1 in normal and malignant hematopoietic cells, and leukemia cell lines. We also attempted to delineate the role of MKRN2 in umbilical cord blood CD34+ stem/progenitor cells and K562 cell line by over-expression and inhibition of MKRN2 through lentivirus transduction and shRNA nucleofection, respectively. Our results provided the first evidence on the ubiquitous expression of MKRN2 in normal hematopoietic cells, embryonic stem cell lines, primary leukemia and leukemic cell lines of myeloid, lymphoid, erythroid and megakaryocytic lineages. The expression levels of MKRN2 were generally higher in primary leukemia samples compared with those in age-matched normal BM cells. In all leukemia subtypes, there was no significant correlation between expression levels of MKRN2 and RAF1. sh-MKRN2-silenced CD34+ cells had a significantly lower proliferation capacity and decreased levels of the early stem/progenitor subpopulation (CFU-GEMM) compared with control cultures. Over-expression of MKRN2 in K562 cells increased cell proliferation. Our results indicated possible roles of MKRN2 in normal and malignant hematopoiesis.
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