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Suganuma M, Watanabe T, Sueoka E, Lim IK, Fujiki H. Role of TNF-α-Inducing Protein Secreted by Helicobacter pylori as a Tumor Promoter in Gastric Cancer and Emerging Preventive Strategies. Toxins (Basel) 2021; 13:181. [PMID: 33804551 PMCID: PMC7999756 DOI: 10.3390/toxins13030181] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 02/20/2021] [Accepted: 02/21/2021] [Indexed: 12/24/2022] Open
Abstract
The tumor necrosis factor-α (TNF-α)-inducing protein (tipα) gene family, comprising Helicobacter pylori membrane protein 1 (hp-mp1) and tipα, has been identified as a tumor promoter, contributing to H. pylori carcinogenicity. Tipα is a unique H. pylori protein with no similarity to other pathogenicity factors, CagA, VacA, and urease. American H. pylori strains cause human gastric cancer, whereas African strains cause gastritis. The presence of Tipα in American and Euro-Asian strains suggests its involvement in human gastric cancer development. Tipα secreted from H. pylori stimulates gastric cancer development by inducing TNF-α, an endogenous tumor promoter, through its interaction with nucleolin, a Tipα receptor. This review covers the following topics: tumor-promoting activity of the Tipα family members HP-MP1 and Tipα, the mechanism underlying this activity of Tipα via binding to the cell-surface receptor, nucleolin, the crystal structure of rdel-Tipα and N-terminal truncated rTipα, inhibition of Tipα-associated gastric carcinogenesis by tumor suppressor B-cell translocation gene 2 (BTG2/TIS21), and new strategies to prevent and treat gastric cancer. Thus, Tipα contributes to the carcinogenicity of H. pylori by a mechanism that differs from those of CagA and VacA.
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Affiliation(s)
- Masami Suganuma
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Tatsuro Watanabe
- Department of Drug Discovery and Biomedical Sciences, Faculty of Medicine, Saga University, Nabeshima, Saga 849-8501, Japan;
| | - Eisaburo Sueoka
- Department of Clinical Laboratory Medicine, Faculty of Medicine, Saga University, Nabeshima, Saga 849-8501, Japan; (E.S.); (H.F.)
| | - In Kyoung Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon 16499, Gyeonggi-do, Korea;
| | - Hirota Fujiki
- Department of Clinical Laboratory Medicine, Faculty of Medicine, Saga University, Nabeshima, Saga 849-8501, Japan; (E.S.); (H.F.)
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Mechanisms of the Epithelial-Mesenchymal Transition and Tumor Microenvironment in Helicobacter pylori-Induced Gastric Cancer. Cells 2020; 9:cells9041055. [PMID: 32340207 PMCID: PMC7225971 DOI: 10.3390/cells9041055] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022] Open
Abstract
Helicobacter pylori (H. pylori) is one of the most common human pathogens, affecting half of the world’s population. Approximately 20% of the infected patients develop gastric ulcers or neoplastic changes in the gastric stroma. An infection also leads to the progression of epithelial–mesenchymal transition within gastric tissue, increasing the probability of gastric cancer development. This paper aims to review the role of H. pylori and its virulence factors in epithelial–mesenchymal transition associated with malignant transformation within the gastric stroma. The reviewed factors included: CagA (cytotoxin-associated gene A) along with induction of cancer stem-cell properties and interaction with YAP (Yes-associated protein pathway), tumor necrosis factor α-inducing protein, Lpp20 lipoprotein, Afadin protein, penicillin-binding protein 1A, microRNA-29a-3p, programmed cell death protein 4, lysosomal-associated protein transmembrane 4β, cancer-associated fibroblasts, heparin-binding epidermal growth factor (HB-EGF), matrix metalloproteinase-7 (MMP-7), and cancer stem cells (CSCs). The review summarizes the most recent findings, providing insight into potential molecular targets and new treatment strategies for gastric cancer.
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Zhu R, Gao C, Wang L, Zhang G, Zhang W, Zhang Z, Shen L, Wang S. Involvement of Aryl Hydrocarbon Receptor and Aryl Hydrocarbon Receptor Repressor in Helicobacter Pylori-related Gastric Pathogenesis. J Cancer 2018; 9:2757-2764. [PMID: 30087718 PMCID: PMC6072820 DOI: 10.7150/jca.26083] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/09/2018] [Indexed: 01/01/2023] Open
Abstract
Background: Persistent Helicobacter pylori (H. pylori) infection leads to various gastric diseases. Multiple studies have demonstrated that aryl hydrocarbon receptor (AHR) plays roles in the antibacterial response and aryl hydrocarbon receptor repressor (AHRR) is downregulated in stomach cancer. However, the role of AHR or AHRR in H. pylori-related gastric diseases remains unclear. Aims: To investigate whether AHR or AHRR is involved in H. pylori-related gastric diseases. Methods: Patients with gastritis or gastric adenocarcinoma were enrolled randomly, and gastric tissue specimens were diagnosed pathologically. AHR, AHRR, and H. pylori infection status in tissues were detected by immunohistochemistry. Human gastric cells were cocultured with H. pylori. siRNAs were used to silence AHR or AHRR, and a C57bl/6 mouse model colonized by H. pylori was established. Protein expression was determined by western blotting analysis, and TNF, IL-8 and IL-1β in cell supernatants were measured by ELISA. Results: AHR and AHRR were expressed in gastritis tissues and gastric cancer tissues without H. pylori infection, and principally located in the cytoplasm and nucleus. AHR expression was significantly correlated with AHRR expression in gastric tissues without H. pylori infection (P=0.008). However, their expressions were negatively correlated with H. pylori infection status. H. pylori coculture inhibited AHR and AHRR expression in stomach mucosa in vitro and in vivo. Gastric cells produced more TNF, IL-8 and IL-1β when AHR or AHRR was silenced. Conclusions: This preliminary study indicates that AHR and AHRR may be involved in H. pylori-related gastric pathogenesis, and helps toward understanding of inflammation-initiated carcinogenesis of gastric cancer.
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Affiliation(s)
- Renfei Zhu
- Division of Gastrointestinal Surgery, Department of General Surgery, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China.,Department of Hepatobiliary Surgery, Third People's Hospital of Nantong, Nantong 226000, China
| | - Cheng Gao
- Division of Gastrointestinal Surgery, Department of General Surgery, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China
| | - Liuhua Wang
- Division of Gastrointestinal Surgery, Department of General Surgery, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China
| | - Guoxin Zhang
- Department of Gastroenterology, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China
| | - Weiming Zhang
- Department of Pathology, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China
| | - Zhihong Zhang
- Department of Pathology, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China
| | - Lizong Shen
- Division of Gastrointestinal Surgery, Department of General Surgery, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, China
| | - Shoulin Wang
- School of Public Health, Nanjing Medical University, Nanjing 211166, China
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Román-Román A, Martínez-Carrillo DN, Atrisco-Morales J, Azúcar-Heziquio JC, Cuevas-Caballero AS, Castañón-Sánchez CA, Reyes-Ríos R, Betancourt-Linares R, Reyes-Navarrete S, Cruz-Del Carmen I, Camorlinga-Ponce M, Cortés-Malagón EM, Fernández-Tilapa G. Helicobacter pylori vacA s1m1 genotype but not cagA or babA2 increase the risk of ulcer and gastric cancer in patients from Southern Mexico. Gut Pathog 2017; 9:18. [PMID: 28413454 PMCID: PMC5390388 DOI: 10.1186/s13099-017-0167-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 04/05/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The vacA, cagA and babA2 genotypes of Helicobacter pylori are associated with gastric pathology. The objectives were to determine the frequency of infection and distribution of the vacA, cagA and babA2 genotypes of H. pylori in patients with gastric ulcer, chronic gastritis and gastric cancer, and to evaluate the association of virulent genotypes with diagnosis. METHODS We studied 921 patients with symptoms of dyspepsia or with presumptive diagnosis of gastric cancer. The DNA of H. pylori and the vacA, cagA and babA2 genes was detected by PCR in total DNA from gastric biopsies. The association of H. pylori and of its cagA, vacA and babA2 genotypes with diagnosis was determined by calculating the odds ratio (OR). RESULTS Chronic gastritis was confirmed in 767 patients, gastric ulcer in 115 and cancer in 39. The prevalence of H. pylori was 47.8, 49.6 and 61.5% in those groups, respectively. H. pylori was more frequent in the surrounding tissue (69.2%) than in the tumor (53.8%). The vacA s1m1 genotype predominated in the three groups (45.2, 61.4 and 83.3%, respectively). H. pylori was associated with cancer (ORadjusted = 2.08; 95% CI 1.05-4.13; p = 0.035) but not with ulcer (ORadjusted = 1.07; 95% CI 0.71-1.61; p = 0.728). The s1m1 genotype was associated with ulcer and cancer (ORadjusted = 2.02; 95% CI 1.12-3.62; p = 0.019 and ORadjusted = 6.58; 95% CI 2.15-20.08; p = 0.001, respectively). babA2 was associated with gastric cancer, and cagA was not associated with the diagnosis. CONCLUSIONS In population from Southern Mexico, H. pylori and the s1m1 genotype were associated with gastric cancer and the s1m1/cagA+/babA2+ strains predominated in tumor and adjacent tissue.
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Affiliation(s)
- Adolfo Román-Román
- Laboratorio de Investigación en Bacteriología, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Chilpancingo, Guerrero México
| | - Dinorah Nashely Martínez-Carrillo
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Avenida Lázaro Cárdenas S/N Ciudad Universitaria Sur, Col. La Haciendita, 39087 Chilpancingo, Guerrero México
| | - Josefina Atrisco-Morales
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Avenida Lázaro Cárdenas S/N Ciudad Universitaria Sur, Col. La Haciendita, 39087 Chilpancingo, Guerrero México
| | - Julio César Azúcar-Heziquio
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Avenida Lázaro Cárdenas S/N Ciudad Universitaria Sur, Col. La Haciendita, 39087 Chilpancingo, Guerrero México
| | - Abner Saúl Cuevas-Caballero
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Avenida Lázaro Cárdenas S/N Ciudad Universitaria Sur, Col. La Haciendita, 39087 Chilpancingo, Guerrero México
| | | | - Roxana Reyes-Ríos
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Avenida Lázaro Cárdenas S/N Ciudad Universitaria Sur, Col. La Haciendita, 39087 Chilpancingo, Guerrero México
| | | | - Salomón Reyes-Navarrete
- Servicio de Endoscopia, Instituto Estatal de Cancerología "Dr. Arturo Beltrán Ortega", Acapulco, Guerrero México
| | - Iván Cruz-Del Carmen
- Servicio de Endoscopia, Hospital General "Dr. Raymundo Abarca Alarcón", Chilpancingo, Guerrero México
| | - Margarita Camorlinga-Ponce
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, IMSS, Ciudad de México, México
| | - Enoc Mariano Cortés-Malagón
- Laboratorio de Biología Molecular del Cáncer, Unidad de Investigación, Hospital Juárez de México, Ciudad de México, México
| | - Gloria Fernández-Tilapa
- Laboratorio de Investigación Clínica, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Avenida Lázaro Cárdenas S/N Ciudad Universitaria Sur, Col. La Haciendita, 39087 Chilpancingo, Guerrero México
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Zou M, Wang F, Jiang A, Xia A, Kong S, Gong C, Zhu M, Zhou X, Zhu J, Zhu W, Cheng W. MicroRNA-3178 ameliorates inflammation and gastric carcinogenesis promoted by Helicobacter pylori new toxin, Tip-α, by targeting TRAF3. Helicobacter 2017; 22. [PMID: 27493095 DOI: 10.1111/hel.12348] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Helicobacter pylori infection is the main cause of chronic gastritis, peptic ulcer, and gastric cancer. Tip-α is a newly identified carcinogenic factor present in H. pylori. TRAF3 can activate NF-κB by both canonical and noncanonical signaling pathways. In this study, we found that the expression of TRAF3 and NF-κB was upregulated, while microRNA-3178 (miR-3178) was decreased in H. pylori-positive gastric tissues but not in H. pylori-negative tissues. MATERIALS AND METHODS GES-1 cells were incubated with 12.5 μg/mL recombinant Tip-α (rTip-α) in RPMI1640 for 2 hours. After another 24 hours, the supernatant medium was designed as inflammatory-conditioned medium (ICM) and that from the untreated control cells was designed as untreated control medium. The release of proinflammatory cytokines from GES-1 cells and proliferation of gastric cancer cells was determined by ELISA and CCK-8 kits. Cells were transfected with the mimic, inhibitor, negative control of miR-3178, or TRAF3 siRNA control siRNA. The medium was then replaced with RPMI1640, 12.5 μg/mL rTip-α, and collected, and the total cellular RNA and protein were extracted for the following detection. RESULTS MiR-3178 mimic prevented the increasement of TRAF3 and hence decreased activation of NF-κB signals, whereas miR-3178 inhibitor could not, in GES-1 cells with Tip-α treatment. The condition medium from miR-3178 mimic transfected GES-1 cells could inhibit proliferation and induce apoptosis of inflammation-related gastric cancer cells SGC7901 and MGC803 by decreasing the production of inflammatory cytokines TNF-α and IL-6, which were secreted by GES-1 cells. CONCLUSIONS Taken all together, Tip-α might activate NF-κB to promote inflammation and carcinogenesis by inhibiting miR-3178 expression, which directly targeting TRAF3, during H. pylori infection in gastric mucosal epithelial cells.
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Affiliation(s)
- Meijuan Zou
- Department of Pharmacology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Fang Wang
- Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Aiqin Jiang
- Medical School of Nanjing University, Nanjing, China
| | - Anliang Xia
- Department of Pharmacology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Siya Kong
- Department of Pharmacology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Chun Gong
- Nanjing University of Chinese Medicine, Nanjing, China
| | - Mingxia Zhu
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xin Zhou
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jun Zhu
- Department of Radiation Oncology, Jiangsu Cancer Hospital, Nanjing, China
| | - Wei Zhu
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Wenfang Cheng
- Department of Gastroenterology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Abstract
Helicobacter pylori is a ubiquitous gastropathogen infecting more than half of the world population. It is associated with dyspepsia, gastritis, gastroduodenal ulcers, mucus-associated lymphoid tissue lymphoma and gastric carcinoma. Current recommended therapy does not eradicate infection in all treated cases and at least 20% post-treatment patients continue to suffer. Salvage therapy helps some of these nonresponders, but resistance to available antibiotics is mounting. Hence, its treatment still remains a daunting task for the practicing physician. Novel medications with improved efficacy and tolerability and with less chances of resistance are required. The present review attempts to discuss the newer patents in this field, which demonstrate a promising future role in the management of H. pylori infection and its consequent problems.
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Suganuma M, Watanabe T, Yamaguchi K, Takahashi A, Fujiki H. Human gastric cancer development with TNF-α-inducing protein secreted from Helicobacter pylori. Cancer Lett 2012; 322:133-8. [PMID: 22459353 DOI: 10.1016/j.canlet.2012.03.027] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 03/13/2012] [Accepted: 03/21/2012] [Indexed: 12/12/2022]
Abstract
TNF-α-inducing protein (Tipα) is a unique carcinogenic factor of Helicobacter pylori, which is secreted into culture broth. The biological activities of Tipα and deletion mutant were studied. Tipα protein specifically binds to cell-surface nucleolin and then enters the gastric cancer cells, where TNF-α and chemokine gene expressions are induced by NF-κB activation. Nucleolin localizes on the surface of gastric cancer cells, and interaction between Tipα and cell-surface nucleolin causes a cancer-oriented microenvironment that increases the risk of gastric cancer. This paper discusses a new mechanism of gastric cancer development with H. pylori and provides a new preventive strategy.
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Affiliation(s)
- Masami Suganuma
- Research Institute for Clinical Oncology, Saitama Cancer Center, Japan.
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Differential host gene responses in mice infected with two highly pathogenic avian influenza viruses of subtype H5N1 isolated from wild birds in Thailand. Virology 2011; 412:9-18. [PMID: 21251691 PMCID: PMC7111900 DOI: 10.1016/j.virol.2010.12.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 10/21/2010] [Accepted: 12/21/2010] [Indexed: 02/05/2023]
Abstract
In Thailand, highly pathogenic avian influenza (HPAI) viruses of subtype H5N1 had been isolated from various wild birds during the HPAI outbreak in poultries. In this study, we examined the pathogenicity of two wild bird isolates (A/Pigeon/Thailand/VSMU-7-NPT/2004; Pigeon04 and A/Tree sparrow/Ratchaburi/VSMU-16-RBR/2005; T.sparrow05) in mice. They showed similar replication in several organs and lethal outcome. However, on day 3 post-infection, Pigeon04 induced mRNA expression of proinflammatory cytokines (IL6 and TNFα) and MIP-2, neutrophil chemoattractant, in the lungs, resulting in severe pneumonia that was accompanied by neutrophil infiltration. In contrast, on day 7 post-infection, T.sparrow05 induced the expression of several cytokines to a greater extent than Pigeon04; it also potently induced mRNA expression of several cytokines in brains of the infected mice that triggered frequent inflammatory events. In sum, our study demonstrated that two HPAI viruses induced different host responses, despite having similar replications, resulting in lethal outcome in mice.
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Abstract
Helicobacter pylori represents the major etiologic agent of gastritis, gastric, and duodenal ulcer disease and can cause gastric cancer and mucosa-associated lymphoid tissue B-cell lymphoma. It is clear that the consequences of infection reflect diverse outcomes of the interaction of bacteria and host immune system. The hope is that by deciphering the deterministic rules--if any--of this interplay, we will eventually be able to predict, treat, and ultimately prevent disease. Over the past year, research on the immunology of this infection started to probe the role of small noncoding RNAs, a novel class of immune response regulators. Furthermore, we learned new details on how infection is detected by innate pattern recognition receptors. Induction of effective cell-mediated immunity will be key for the development of a vaccine, and new work published analyzed the relevance and contribution of CD4 T helper cell subsets to the immune reaction. Th17 cells, which are also induced during natural infection, were shown to be particularly important for vaccination. Cost-efficiency of vaccination was re-assessed and confirmed. Thus, induction and shaping of the effector roles of such protective Th populations will be a target of the newly described vaccine antigens, formulations, and modes of application that we also review here.
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Watanabe T, Tsuge H, Imagawa T, Kise D, Hirano K, Beppu M, Takahashi A, Yamaguchi K, Fujiki H, Suganuma M. Nucleolin as cell surface receptor for tumor necrosis factor-alpha inducing protein: a carcinogenic factor of Helicobacter pylori. J Cancer Res Clin Oncol 2010; 136:911-21. [PMID: 20049476 DOI: 10.1007/s00432-009-0733-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Accepted: 11/13/2009] [Indexed: 12/16/2022]
Abstract
PURPOSE Tumor necrosis factor-alpha inducing protein (Tipalpha) is a unique carcinogenic factor released from Helicobacter pylori (H. pylori). Tipalpha specifically binds to cells and is incorporated into cytosol and nucleus, where it strongly induces expression of TNF-alpha and chemokine genes mediated through NF-kappaB activation, resulting in tumor development. To elucidate mechanism of action of Tipalpha, we studied a binding protein of Tipalpha in gastric epithelial cells. METHODS Tipalpha binding protein was found in cell lysates of mouse gastric cancer cell line MGT-40 by FLAG-pull down assay and identified to be cell surface nucleolin by flow cytometry using anti-nucleolin antibody. Incorporation of Tipalpha into the cells was determined by Western blotting and expression of TNF-alpha gene was quantified by RT-PCR. RESULTS Nucleolin was co-precipitated with Tipalpha-FLAG, but not with del-Tipalpha-FLAG (an inactive mutant). After treatment with Tipalpha-FLAG, incorporated Tipalpha was co-immunoprecipitated with endogenous nucleolin using anti-nucleolin antibody. The direct binding of Tipalpha to recombinant His-tagged nucleolin fragment (284-710) was also confirmed. Although nucleolin is an abundant non-ribosomal protein of the nucleolus, we found that nucleolin is present on the cell surface of MGT-40 cells. Pretreatment with anti-nucleolin antibody enhanced Tipalpha-incorporation into the cells through nucleolin internalization. In addition, pretreatment with tunicamycin, an inhibitor of N-glycosylation, decreased the amounts of cell surface nucleolin and inhibited both internalization of Tipalpha and expression of TNF-alpha gene. CONCLUSIONS All the results indicate that nucleolin acts as a receptor for Tipalpha and shuttles Tipalpha from cell surface to cytosol and nuclei. These findings provide a new mechanistic insight into gastric cancer development with Tipalpha.
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Affiliation(s)
- Tatsuro Watanabe
- Saitama Cancer Center, Research Institute for Clinical Oncology, Kitaadachi-gun, Saitama 362-0806, Japan
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