Xue ZJ, Gong YN, He LH, Sun L, You YH, Fan DJ, Zhang MJ, Yan XM, Zhang JZ. Amino acid deletions at positions 893 and 894 of cytotoxin-associated gene A protein affect Helicobacter pylori gastric epithelial cell interactions. World J Gastroenterol 2024; 30(41): 4449-4460 [PMID: 39534413 DOI: 10.3748/wjg.v30.i41.4449]
Corresponding Author of This Article
Jian-Zhong Zhang, MD, Professor, National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, No. 155 Changbai Road, Changping District, Beijing 102206, China. zhangjianzhong@icdc.cn
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Basic Study
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Zhi-Jing Xue, Research Center of Translational Medicine, Central Hospital Affiliated to Shandong First Medical University, Jinan 250013, Shandong Province, China
Ya-Nan Gong, Li-Hua He, Lu Sun, Yuan-Hai You, Dong-Jie Fan, Mao-Jun Zhang, Xiao-Mei Yan, Jian-Zhong Zhang, National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Author contributions: Xue ZJ and Zhang JZ designed the research study; Gong YN and He LH constructed the recombinant plasmids; Sun L, You YH, and Fan DJ performed the DNA extraction; Xue ZJ, Zhang MJ, and Yan XM analyzed the data and wrote the manuscript; Zhang JZ reviewed and revised the manuscript; and all authors have read and approved the final manuscript.
Supported bythe Shandong Medical and Health Science and Technology Development Plan Project, No. 202202080452.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of the National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention (approval No. ICDC-2013001).
Conflict-of-interest statement: The authors have no conflicts of interest and financial disclosures.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Jian-Zhong Zhang, MD, Professor, National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, No. 155 Changbai Road, Changping District, Beijing 102206, China. zhangjianzhong@icdc.cn
Received: March 12, 2024 Revised: September 29, 2024 Accepted: October 12, 2024 Published online: November 7, 2024 Processing time: 225 Days and 4.1 Hours
Abstract
BACKGROUND
Helicobacter pylori (H. pylori) persistently colonizes the human gastric mucosa in more than 50% of the global population, leading to various gastroduodenal diseases ranging from chronic gastritis to gastric carcinoma. Cytotoxin-associated gene A (CagA) protein, an important oncoprotein, has highly polymorphic Glu-Pro-Ile-Tyr-Ala segments at the carboxyl terminus, which play crucial roles in pathogenesis. Our previous study revealed a significant association between amino acid deletions at positions 893 and 894 and gastric cancer.
AIM
To investigate the impact of amino acid deletions at positions 893 and 894 on CagA function.
METHODS
We selected a representative HZT strain from a gastric cancer patient with amino acid deletions at positions 893 and 894. The cagA gene was amplified and mutated into cagA-NT and cagA-NE (sequence characteristics of strains from nongastric cancer patients), cloned and inserted into pAdtrack-CMV, and then transfected into AGS cells. The expression of cagA and its mutants was examined using real-time polymerase chain reaction and Western blotting, cell elongation via cell counting, F-actin cytoskeleton visualization using fluorescence staining, and interleukin-8 (IL-8) secretion via enzyme-linked immunosorbent assay.
RESULTS
The results revealed that pAdtrack/cagA induced a more pronounced hummingbird phenotype than pAdtrack/cagA-NT and pAdtrack/cagA-NE (40.88 ± 3.10 vs 32.50 ± 3.17, P < 0.001 and 40.88 ± 3.10 vs 32.17 ± 3.00, P < 0.001) at 12 hours after transfection. At 24 hours, pAdtrack/cagA-NE induced significantly fewer hummingbird phenotypes than pAdtrack/cagA and pAdtrack/cagA-NT (46.02 ± 2.12 vs 53.90 ± 2.10, P < 0.001 and 46.02 ± 2.12 vs 51.15 ± 3.74, P < 0.001). The total amount of F-actin caused by pAdtrack/cagA was significantly lower than that caused by pAdtrack/cagA-NT and pAdtrack/cagA-NE (27.54 ± 17.37 vs 41.51 ± 11.90, P < 0.001 and 27.54 ± 17.37 vs 41.39 ± 14.22, P < 0.001) at 12 hours after transfection. Additionally, pAdtrack/cagA induced higher IL-8 secretion than pAdtrack/cagA-NT and pAdtrack/cagA-NE at different times after transfection.
CONCLUSION
Amino acid deletions at positions 893 and 894 enhance CagA pathogenicity, which is crucial for revealing the pathogenic mechanism of CagA and identifying biomarkers of highly pathogenic H. pylori.
Core Tip: The present study evaluated the impact of amino acid deletions at positions 893 and 894 on cytotoxin-associated gene A (CagA) protein function. Amino acid deletions at positions 893 and 894 enhance the ability of CagA to induce hummingbird cells, cytoskeletal rearrangement, and interleukin-8 secretion. This finding is crucial for elucidating the molecular mechanism of CagA protein pathogenicity and identifying biomarkers of highly pathogenic Helicobacter pylori.
