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World J Meta-Anal. Jun 28, 2021; 9(3): 257-276
Published online Jun 28, 2021. doi: 10.13105/wjma.v9.i3.257
Immune response to Helicobacter pylori infection and gastric cancer development
Breno Bittencourt de Brito, Fabian Fellipe Bueno Lemos, Caroline da Mota Carneiro, Andressa Santos Viana, Nilo Manoel Pereira Vieira Barreto, Gabriela Alves de Souza Assis, Barbara Dicarlo Costa Braga, Maria Luísa Cordeiro Santos, Filipe Antônio França da Silva, Hanna Santos Marques, Natália Oliveira e Silva, Fabrício Freire de Melo
Breno Bittencourt de Brito, Fabian Fellipe Bueno Lemos, Caroline da Mota Carneiro, Andressa Santos Viana, Nilo Manoel Pereira Vieira Barreto, Gabriela Alves de Souza Assis, Barbara Dicarlo Costa Braga, Maria Luísa Cordeiro Santos, Filipe Antônio França da Silva, Natália Oliveira e Silva, Fabrício Freire de Melo, Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
Hanna Santos Marques, Campus Vitória da Conquista, Universidade Estadual do Sudoeste da Bahia, Vitória da Conquista 45031900, Bahia, Brazil
Author contributions: All authors equally contributed to this paper with conception and design of the study, literature review and analysis, drafting and critical revision and editing, and final approval of the final version.
Conflict-of-interest statement: No potential conflicts of interest.
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: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Fabrício Freire de Melo, MSc, PhD, Postdoc, Professor, Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Rua Hormindo Barros, 58, Quadra 17, Lote 58, Bairro Candeias, Vitória da Conquista 45029-094, Bahia, Brazil. freiremelo@yahoo.com.br
Received: February 23, 2021
Peer-review started: February 23, 2021
First decision: April 6, 2021
Revised: April 24, 2021
Accepted: June 15, 2021
Article in press: June 15, 2021
Published online: June 28, 2021
Processing time: 139 Days and 7.4 Hours
Abstract

Gastric adenocarcinoma is a global health concern, and Helicobacter pylori (H. pylori) infection is the main risk factor for its occurrence. Of note, the immune response against the pathogen seems to be a determining factor for gastric oncogenesis, and increasing evidence have emphasized several host and bacterium factors that probably influence in this setting. The development of an inflammatory process against H. pylori involves a wide range of mechanisms such as the activation of pattern recognition receptors and intracellular pathways resulting in the production of proinflammatory cytokines by gastric epithelial cells. This process culminates in the establishment of distinct immune response profiles that result from the cytokine-induced differentiation of T naïve cells into specific T helper cells. Cytokines released from each type of T helper cell orchestrate the immune system and interfere in the development of gastric cancer in idiosyncratic ways. Moreover, variants in genes such as single nucleotide polymorphisms have been associated with variable predispositions for the occurrence of gastric malignancy because they influence both the intensity of gene expression and the affinity of the resultant molecule with its receptor. In addition, various repercussions related to some H. pylori virulence factors seem to substantially influence the host immune response against the infection, and many of them have been associated with gastric tumorigenesis.

Keywords: Gastric cancer; Helicobacter pylori; Immune response; Virulence factors; Polymorphisms

Core Tip: Gastric cancer affects more than 1 million people yearly, and Helicobacter pylori (H. pylori) infection is the main risk factor for that malignancy. Moreover, the immune response against the infection seems to play a pivotal role in gastric carcinogenesis. This article provides a broad and updated overview on the main aspects regarding H. pylori infection, immune response, and gastric cancer development.