Polymorphism in Toll-Like Receptors and Helicobacter Pylori Motility in Autoimmune Atrophic Gastritis and Gastric Cancer

Autoimmune atrophic gastritis (AAG) is associated with an increased risk of certain types of gastric cancer (GC). Helicobacter pylori (H. pylori) infection may have a role in the induction and/or maintenance of AAG and GC. Toll-like receptors (TLR) are essential for H. pylori recognition and subsequent innate and adaptive immunity responses. This study therefore aimed to characterize TLR polymorphisms, and features of bacterial flagellin A in samples from patients with AAG (n = 67), GC (n = 114) and healthy donors (HD; n = 97). TLR5 rs5744174 C/C genotype was associated with GC, lower IgG anti H. pylori response and a higher H. pylori flagellin A abundance and motility. In a subset of patients with AAG, H. pylori strains showed a reduction of the flagellin A abundance and a moderate motility compared with strains from GC patients, a prerequisite for active colonization of the deeper layers of the mucosa, host immune response and inflammation. TLR9 rs5743836 T allele showed an association with serum gastrin G17. In conclusion, our study suggests that alterations of flaA protein, moderate motility in H. pylori and two polymorphisms in TLR5 and TLR9 may favor the onset of AAG and GC, at least in a subset of patients. These findings corroborate the function of pathogen–host cell interactions and responses, likely influencing the pathogenetic process.

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TLR1 and PRKAA1 Gene Polymorphisms in the Development of Atrophic Gastritis and Gastric Cancer

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.274.tlr ◽

2018 ◽

Vol 27 (4) ◽

pp. 363-369 ◽

Cited By ~ 4

Author(s):

Gintare Dargiene ◽

Greta Streleckiene ◽

Jurgita Skieceviciene ◽

Marcis Leja ◽

Alexander Link ◽

...

Keyword(s):

Gastric Cancer ◽

Atrophic Gastritis ◽

Genetic Polymorphisms ◽

Association Studies ◽

Control Group ◽

Similar Distribution ◽

Genome Wide Association Studies ◽

Increased Risk ◽

Infection Susceptibility ◽

H Pylori

Background & Aims: Previous genome-wide association studies showed that genetic polymorphisms in toll-like receptor 1 (TLR1) and protein kinase AMP-activated alpha 1 catalytic subunit (PRKAA1) genes were associated with gastric cancer (GC) or increased Helicobacter pylori (H. pylori) infection susceptibility. The aim of this study was to evaluate the association between TLR1 and PRKAA1 genes polymorphisms and H.pylori infection, atrophic gastritis (AG) or GC in the European population.Methods: Single-nucleotide polymorphisms (SNPs) were analysed in 511 controls, 340 AG patients and 327 GC patients. TLR1 C>T (rs4833095) and PRKAA1 C>T (rs13361707) were genotyped by the real-time polymerase chain reaction. H. pylori status was determined by testing for anti-H. pylori IgG antibodies in the serum.Results: The study included 697 (59.2%) H. pylori positive and 481 (40.8%) H. pylori negative cases. We observed similar distribution of TLR1 and PRKAA1 alleles and genotypes in H. pylori positive and negative cases. TLR1 and PRKAA1 SNPs were not linked with the risk of AG. TC genotype of TLR1 gene was more prevalent in GC patients compared to the control group (29.7% and 22.3% respectively, p=0.002). Carriers of TC genotype had a higher risk of GC (aOR=1.89, 95% CI: 1.26–2.83, p=0.002). A similar association was observed in a dominant inheritance model for TLR1 gene SNP, where comparison of CC+TC vs. TT genotypes showed an increased risk of GC (aOR=1.86, 95% CI: 1.26–2.75, p=0.002). No association between genetic polymorphism in PRKAA1 gene and GC was observed.Conclusions: TLR1 rs4833095 SNP was associated with an increased risk of GC in a European population, while PRKAA1 rs13361707 genetic variant was not linked with GC. Both genetic polymorphisms were not associated with H. pylori infection susceptibility or the risk of AG.

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Proteomics signature of autoimmune atrophic gastritis: towards a link with gastric cancer

Gastric Cancer ◽

10.1007/s10120-020-01148-3 ◽

2021 ◽

Author(s):

Ombretta Repetto ◽

Valli De Re ◽

Paolo Giuffrida ◽

Marco Vincenzo Lenti ◽

Raffaella Magris ◽

...

Keyword(s):

Gastric Cancer ◽

Atrophic Gastritis ◽

Tricarboxylic Acid Cycle ◽

Differential Abundance ◽

Expression Levels ◽

2D Dige ◽

Gastric Corpus ◽

Gastric Biopsies ◽

H Pylori ◽

Autoimmune Atrophic Gastritis

Abstract Background Autoimmune atrophic gastritis (AAG) is a chronic disease that can progress to gastric cancer (GC). To better understand AAG pathology, this proteomics study investigated gastric proteins whose expression levels are altered in this disease and also in GC. Methods Using two-dimensional difference gel electrophoresis (2D-DIGE), we compared protein maps of gastric corpus biopsies from AAG patients and controls. Differentially abundant spots (|fold change|≥ 1.5, P < 0.01) were selected and identified by LC–MS/MS. The spots were further assessed in gastric antrum biopsies from AAG patients (without and with Helicobacter pylori infection) and from GC patients and unaffected first-degree relatives of GC patients. Results 2D-DIGE identified 67 differentially abundant spots, with 28 more and 39 less abundant in AAG-corpus than controls. LC–MS/MS identified these as 53 distinct proteins. The most significant (adjusted P < 0.01) biological process associated with the less abundant proteins was “tricarboxylic acid cycle”. Of the 67 spots, 57 were similarly differentially abundant in AAG-antrum biopsies irrespective of H. pylori infection status. The differential abundance was also observed in GC biopsies for 14 of 28 more abundant and 35 of 39 less abundant spots, and in normal gastric biopsies of relatives of GC patients for 6 and 25 spots, respectively. Immunoblotting confirmed the different expression levels of two more abundant proteins (PDIA3, GSTP gene products) and four less abundant proteins (ATP5F1A, PGA3, SDHB, PGC). Conclusion This study identified a proteomics signature of AAG. Many differential proteins were shared by GC and may be involved in the progression of AAG to GC.

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Genetic Polymorphisms of CXCL8 (−251) Are Associated with the Susceptibility of Helicobacter pylori Infection Increased the Risk of Inflammation and Gastric Cancer in Thai Gastroduodenal Patients

Iranian Journal of Allergy Asthma and Immunology ◽

10.18502/ijaai.v18i4.1417 ◽

2019 ◽

Cited By ~ 1

Author(s):

Wongwarut Boonyanugomol ◽

Kamolchanok Rukseree ◽

Worrarat Kongkasame ◽

Prasit Palittapongarnpim ◽

Seung-Chul Baik ◽

...

Keyword(s):

Gene Expression ◽

Gastric Cancer ◽

Helicobacter Pylori ◽

Cancer Progression ◽

Chemokine Receptor ◽

Gene Polymorphisms ◽

Inflammatory Responses ◽

Increased Risk ◽

Cxc Chemokine ◽

H Pylori

CXC Chemokine Ligand 8 (CXCL8) plays an important role in gastric inflammation and in the progression of gastric cancer induced by Helicobacter pylori (H. pylori) infection. The association of CXCL8, CXC Chemokine Receptor 1 (CXCR1), and CXC Chemokine Receptor 2 (CXCR2) polymorphisms with H. pylori infection and gastric cancer progression needs to be investigated in a population within an enigma area consisting of multiple ethnicities, such as Thailand. To analyze the relative risk of H. pylori infection and gastric cancer among Thai gastroduodenal patients, gene polymorphisms in CXCL8 (promoter region -251) and in CXCR1 and CXCR2 (receptors for CXCL8) were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele specific-PCR (AS-PCR). We also determined the presence of cytotoxin-associated gene A (cagA) in Thai patients with H. pylori infection. Correlation between the CXCL8 (-251) polymorphism and CXCL8 gene expression was evaluated by quantitative reverse transcriptase-PCR (qRT-PCR). We found a significant association between the T/A and A/A genotypes of CXCL8 (-251) with H. pylori infection. However, no significant correlation was found between the CXCR1 (+2607) and CXCR2 (+1208) gene polymorphisms with H. pylori infection among Thai gastroduodenal subjects. Within the H. pylori-infected group of Thai gastroduodenal patients, no significant differences in cagA were observed. In addition, the A/A genotype of CXCL8 (-251) significantly correlated with the risk of gastric cancer and correlated with higher CXCL8 gene expression levels in Thai gastroduodenal patients. These results suggest that CXCL8 (-251) polymorphisms are associated with H. pylori infection, an increased risk of stronger inflammatory responses, and gastric cancer in Thai gastroduodenal patients.

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LncRNA H19 induced by helicobacter pylori infection promotes gastric cancer cell growth via enhancing NF-κB-induced inflammation

Journal of Inflammation ◽

10.1186/s12950-019-0226-y ◽

2019 ◽

Vol 16 (1) ◽

Cited By ~ 2

Author(s):

Yifeng Zhang ◽

Jin Yan ◽

Chao Li ◽

Xiaoyong Wang ◽

Yu Dong ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Cell Growth ◽

Migration And Invasion ◽

Cancer Cell Growth ◽

Protein Levels ◽

Non Coding Rna ◽

Healthy Donors ◽

H Pylori ◽

Long Non Coding Rna

Abstract Background The aim of this study was to investigate the role of long non-coding RNA (lncRNA) H19 in gastric cancer (GC) with Helicobacter pylori (H. pylori). Methods H19 expression in peripheral blood from H. pylori+/− GC patients and healthy donors (control) as well as in GC tissues and cells were detected by qRT-PCR. Cell proliferation was evaluated by CCK-8 assay. Cell migration and invasion were evaluated by Transwell assay. The levels of pro-inflammatory cytokines were determined by ELISA. The protein levels of IκBα, p-IκBα and p65 were determined by western blotting. Results H19 expression was upregulated in H. pylori-infected GC tissues and cells. Furthermore, H. pylori promoted GC cell viability, migration, invasion and inflammatory response. Moreover, H19 overexpression promoted the proliferation, migration and invasion of H. pylori-infected GC cells via enhancing NF-κB-induced inflammation. Conclusions LncRNA H19 promotes H. pylori-induced GC cell growth via enhancing NF-κB-induced inflammation.

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Eradication of Helicobacter pylori and Gastric Cancer: A Controversial Relationship

Frontiers in Microbiology ◽

10.3389/fmicb.2021.630852 ◽

2021 ◽

Vol 12 ◽

Author(s):

Mariagrazia Piscione ◽

Mariangela Mazzone ◽

Maria Carmela Di Marcantonio ◽

Raffaella Muraro ◽

Gabriella Mincione

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Atrophic Gastritis ◽

Precancerous Lesions ◽

Eradication Therapy ◽

Developed Countries ◽

Gastric Carcinogenesis ◽

Gastric Disease ◽

Type I ◽

H Pylori

Worldwide, gastric cancer (GC) represents the fifth cancer for incidence, and the third as cause of death in developed countries. Indeed, it resulted in more than 780,000 deaths in 2018. Helicobacter pylori appears to be responsible for the majority of these cancers. On the basis of recent studies, and either alone or combined with additional etiological factors, H. pylori is considered a “type I carcinogen.” Over recent decades, new insights have been obtained into the strategies that have been adopted by H. pylori to survive the acidic conditions of the gastric environment, and to result in persistent infection, and dysregulation of host functions. The multistep processes involved in the development of GC are initiated by transition of the mucosa into chronic non-atrophic gastritis, which is primarily triggered by infection with H. pylori. This gastritis then progresses into atrophic gastritis and intestinal metaplasia, and then to dysplasia, and following Correa’s cascade, to adenocarcinoma. The use of antibiotics for eradication of H. pylori can reduce the incidence of precancerous lesions only in the early stages of gastric carcinogenesis. Here, we first survey the etiology and risk factors of GC, and then we analyze the mechanisms underlying tumorigenesis induced by H. pylori, focusing attention on virulence factor CagA, inflammation, oxidative stress, and ErbB2 receptor tyrosine kinase. Moreover, we investigate the relationships between H. pylori eradication therapy and other diseases, considering not only cardia (upper stomach) cancers and Barrett’s esophagus, but also asthma and allergies, through discussion of the “hygiene hypothesis. ” This hypothesis suggests that improved hygiene and antibiotic use in early life reduces microbial exposure, such that the immune response does not become primed, and individuals are not protected against atopic disorders, asthma, and autoimmune diseases. Finally, we overview recent advances to uncover the complex interplay between H. pylori and the gut microbiota during gastric carcinogenesis, as characterized by reduced bacterial diversity and increased microbial dysbiosis. Indeed, it is of particular importance to identify the bacterial taxa of the stomach that might predict the outcome of gastric disease through the stages of Correa’s cascade, to improve prevention and therapy of gastric carcinoma.

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Gastric Microbiota in Helicobacter pylori-Negative and -Positive Gastritis Among High Incidence of Gastric Cancer Area

Cancers ◽

10.3390/cancers11040504 ◽

2019 ◽

Vol 11 (4) ◽

pp. 504 ◽

Cited By ~ 14

Author(s):

Boldbaatar Gantuya ◽

Hashem B. El-Serag ◽

Takashi Matsumoto ◽

Nadim J. Ajami ◽

Khasag Oyuntsetseg ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Bacterial Species ◽

Rrna Gene ◽

Linear Discriminant ◽

Haemophilus Parainfluenzae ◽

Increased Risk ◽

Comparison Groups ◽

H Pylori ◽

Gastric Microbiota

Helicobacter pylori (H. pylori) related chronic gastritis is a well-known major etiological factor for gastric cancer development. However, H. pylori-negative gastritis (HpN) is not well described. We aimed to examine gastric mucosal microbiota in HpN compared to H. pylori-positive gastritis (HpP) and H. pylori-negative non-gastritis group (control). Here, we studied 11 subjects with HpN, 40 with HpP and 24 controls. We performed endoscopy with six gastric biopsies. Comparison groups were defined based on strict histological criteria for the disease and H. pylori diagnosis. We used 16S rRNA gene amplicon sequencing to profile the gastric microbiota according to comparison groups. These results demonstrate that the HpP group had significantly lower bacterial richness by the operational taxonomic unit (OTU) counts, and Shannon and Simpson indices as compared to HpN or controls. The linear discriminant analysis effect size analysis showed the enrichment of Firmicutes, Fusobacteria, Bacteroidetes and Actinobacteria at phylum level in the HpN group. In the age-adjusted multivariate analysis, Streptococcus sp. and Haemophilus parainfluenzae were at a significantly increased risk for HpN (odds ratio 18.9 and 12.3, respectively) based on abundance. Treponema sp. was uniquely found in HpN based on occurrence. In this paper, we conclude that Streptococcus sp., Haemophilus parainfluenzae and Treponema sp. are candidate pathogenic bacterial species for HpN. These results if confirmed may have important clinical implications.

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Differential Helicobacter pylori Plasticity in the Gastric Niche of Subjects at Increased Gastric Cancer Risk

Pathogens ◽

10.3390/pathogens8020065 ◽

2019 ◽

Vol 8 (2) ◽

pp. 65

Author(s):

Mariateresa Casarotto ◽

Chiara Pratesi ◽

Ettore Bidoli ◽

Stefania Maiero ◽

Raffaella Magris ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Precancerous Lesions ◽

Neutrophil Infiltration ◽

Host Bacterium ◽

Gastric Cancer Risk ◽

Increased Risk ◽

Cytotoxin Associated Gene A ◽

Sydney System ◽

H Pylori

Helicobacter pylori (H. pylori) represents an independent risk factor for Gastric Cancer (GC). First Degree Relatives (FDR) of GC subjects and Autoimmune Gastritis (AG) patients are both at increased risk for GC. H. pylori genetic heterogeneity within the gastric niche of FDR and AG individuals has been little explored. To understand whether they exploit an increased H. pylori stability and virulence, 14 AG, 25 FDR, 39 GC and 13 dyspeptic patients (D) were investigated by a cultural PCR-based approach characterizing single colonies-forming-units. We chose three loci within the Cytotoxin-associated gene-A Pathogenicity Island (CagPAI) (cagA,cagE,virB11), vacA, homA and homB as markers of virulence with reported association to GC. Inflammatory/precancerous lesions were staged according to Sydney System. When compared to D, FDR, similarly to GC patients, were associated to higher atrophy (OR = 6.29; 95% CI:1.23–31.96 in FDR; OR = 7.50; 95% CI:1.67–33.72 in GC) and a lower frequency of mixed infections (OR = 0.16; 95% CI:0.03–0.81 in FDR; OR = 0.10; 95% CI:0.02–0.48 in GC). FDR presented also an increased neutrophil infiltration (OR = 7.19; 95% CI:1.16–44.65). Both FDR and GC carried a higher proportion of CagPAI+vacAs1i1mx+homB+ profiles (OR = 2.71; 95% CI: 1.66–4.41 and OR = 3.43; 95% CI: 2.16–5.44, respectively). Conversely, AG patients presented a lower frequency of subtypes carrying a stable CagPAI and vacAs1i1mx. These results underline different H. pylori plasticity in FDR and AG individuals, and thus, a different host-bacterium interaction capacity that should be considered in the context of eradication therapies.

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Precancerous Gastric Lesions with Helicobacter pylori vacA+/babA2+/oipA+ Genotype Increase the Risk of Gastric Cancer

BioMed Research International ◽

10.1155/2020/7243029 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Theeraya Simawaranon Bartpho ◽

Wareeporn Wattanawongdon ◽

Taweesak Tongtawee ◽

Chatchanok Paoin ◽

Kokiet Kangwantas ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Clinical Outcomes ◽

Chronic Gastritis ◽

Virulence Genes ◽

Gastric Lesions ◽

Precancerous Gastric Lesions ◽

Increased Risk ◽

H Pylori ◽

Gastric Cancer Patients

Objective. The clinical outcomes of gastric diseases such as chronic gastritis, peptic ulcer, and gastric cancer have been attributed to the interplay of virulence factors of Helicobacter pylori (H. pylori), host genetic susceptibility, and host immune responses. This study investigated the presence of cagA, vacA, iceA2, babA2, and oipA genes and their association with clinical outcomes. Methods. Chronic gastritis, atrophic gastritis, and intestinal metaplasia specimens were obtained from patients who underwent endoscopy and surgical resection between January 2017 and December 2018; specimens from gastric cancer patients treated between January 2014 and December 2018 were also added. H. pylori infection and virulence genes (cagA, vacA, iceA2, babA2, and oipA) were determined using real-time PCR. The association between H. pylori genotypes and clinical outcomes were evaluated using multivariate regression model analysis. The overall survival of gastric cancer patients was compared between genotype combinations. Results. H. pylori was positive in 166 patients with chronic gastritis, precancerous gastric lesions, and gastric cancer. The genes vacA, babA2, and oipA were most prevalent in chronic gastritis (73%), precancerous gastric lesions (62%), and gastric cancer (91%), respectively. The vacA, babA2, and oipA genes were associated with increased risk of gastric cancer (OR = 1.23; 95% CI = 1.13–3.32; P=0.033, OR = 2.64; 95% CI = 1.44–4.82, P=0.024, and OR = 2.79; 95% CI = 1.58–5.41; P=0.031, respectively). Interestingly, H. pylori vacA+/babA2+/oipA+ genotype infection was associated with increased risk of gastric cancer (OR = 3.85, 95% CI = 1.67–5.77, P=0.014). Conclusion. In this present study, we reported on the virulence genes of H. pylori infection to reveal their association with increased risk of chronic gastritis, precancerous gastric lesions, and gastric cancer. Precancerous gastric lesions with H. pylori vacA+/babA2+/oipA+ genotype increased the risk of gastric cancer.

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Rejuvenation of Helicobacter pylori–Associated Atrophic Gastritis Through Concerted Actions of Placenta-Derived Mesenchymal Stem Cells Prevented Gastric Cancer

Frontiers in Pharmacology ◽

10.3389/fphar.2021.675443 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jong Min Park ◽

Young Min Han ◽

Ki Baik Hahm

Keyword(s):

Gastric Cancer ◽

Stem Cells ◽

Helicobacter Pylori ◽

Mesenchymal Stem Cells ◽

Atrophic Gastritis ◽

Conditioned Medium ◽

Gastric Atrophy ◽

Control Group ◽

Therapeutic Effects ◽

H Pylori

Chronic Helicobacter pylori infection causes gastric cancer via the progression of precancerous chronic atrophic gastritis (CAG). Therefore, repairing gastric atrophy could be a useful strategy in preventing H. pylori–associated gastric carcinogenesis. Although eradication of the bacterial pathogen offers one solution to this association, this study was designed to evaluate an alternative approach using mesenchymal stem cells to treat CAG and prevent carcinogenesis. Here, we used human placenta-derived mesenchymal stem cells (PD-MSCs) and their conditioned medium (CM) to treat H. pylori–associated CAG in a mice/cell model to explore their therapeutic effects and elucidate their molecular mechanisms. We compared the changes in the fecal microbiomes in response to PD-MSC treatments, and chronic H. pylori–infected mice were given ten treatments with PD-MSCs before being sacrificed for end point assays at around 36 weeks of age. These animals presented with significant reductions in the mean body weights of the control group, which were eradicated following PD-MSC treatment (p < 0.01). Significant changes in various pathological parameters including inflammation, gastric atrophy, erosions/ulcers, and dysplastic changes were noted in the control group (p < 0.01), but these were all significantly reduced in the PD-MSC/CM-treated groups. Lgr5+, Ki-67, H+/K+-ATPase, and Musashi-1 expressions were all significantly increased in the treated animals, while inflammatory mediators, MMP, and apoptotic executors were significantly decreased in the PD-MSC group compared to the control group (p < 0.001). Our model showed that H. pylori–initiated, high-salt diet–promoted gastric atrophic gastritis resulted in significant changes in the fecal microbiome at the phylum/genus level and that PD-MSC/CM interventions facilitated a return to more normal microbial communities. In conclusion, administration of PD-MSCs or their conditioned medium may present a novel rejuvenating agent in preventing the progression of H. pylori–associated premalignant lesions.

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Pathways of Gastric Carcinogenesis, Helicobacter pylori Virulence and Interactions with Antioxidant Systems, Vitamin C and Phytochemicals

International Journal of Molecular Sciences ◽

10.3390/ijms21176451 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6451 ◽

Cited By ~ 2

Author(s):

James W. T. Toh ◽

Robert B. Wilson

Keyword(s):

Gastric Cancer ◽

Ascorbic Acid ◽

Helicobacter Pylori ◽

Vitamin C ◽

Atrophic Gastritis ◽

Chronic Atrophic Gastritis ◽

Gastric Carcinogenesis ◽

Antioxidant Systems ◽

H Pylori

Helicobacter pylori is a class one carcinogen which causes chronic atrophic gastritis, gastric intestinal metaplasia, dysplasia and adenocarcinoma. The mechanisms by which H. pylori interacts with other risk and protective factors, particularly vitamin C in gastric carcinogenesis are complex. Gastric carcinogenesis includes metabolic, environmental, epigenetic, genomic, infective, inflammatory and oncogenic pathways. The molecular classification of gastric cancer subtypes has revolutionized the understanding of gastric carcinogenesis. This includes the tumour microenvironment, germline mutations, and the role of Helicobacter pylori bacteria, Epstein Barr virus and epigenetics in somatic mutations. There is evidence that ascorbic acid, phytochemicals and endogenous antioxidant systems can modify the risk of gastric cancer. Gastric juice ascorbate levels depend on dietary intake of ascorbic acid but can also be decreased by H. pylori infection, H. pylori CagA secretion, tobacco smoking, achlorhydria and chronic atrophic gastritis. Ascorbic acid may be protective against gastric cancer by its antioxidant effect in gastric cytoprotection, regenerating active vitamin E and glutathione, inhibiting endogenous N-nitrosation, reducing toxic effects of ingested nitrosodimethylamines and heterocyclic amines, and preventing H. pylori infection. The effectiveness of such cytoprotection is related to H. pylori strain virulence, particularly CagA expression. The role of vitamin C in epigenetic reprogramming in gastric cancer is still evolving. Other factors in conjunction with vitamin C also play a role in gastric carcinogenesis. Eradication of H. pylori may lead to recovery of vitamin C secretion by gastric epithelium and enable regression of premalignant gastric lesions, thereby interrupting the Correa cascade of gastric carcinogenesis.

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