Polymorphisms of TLR9 gene are associated with a decreased risk of H. pylori infection in a Chinese population

Abstract Background The cytotoxin-associated gene A (cagA) is one of the most important virulence factors of Helicobacter pylori (H. pylori). There is a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA) repeat region in the C-terminal of CagA protein. This repeat region is thought to play an important role in the pathogenesis of gastrointestinal diseases. The aim of this study was to investigate the diversity of cagA 3′ variable region and the amino acid polymorphisms in the EPIYA segments of the CagA C-terminal region of H. pylori, and their association with gastroduodenal diseases. Methods A total of 515 H. pylori strains from patients in 14 different geographical regions of China were collected. The genomic DNA from each strain was extracted and the cagA 3′ variable region was amplified by polymerase chain reaction (PCR). The PCR products were sequenced and analyzed using MEGA 7.0 software. Results A total of 503 (97.7%) H. pylori strains were cagA-positive and 1,587 EPIYA motifs were identified, including 12 types of EPIYA or EPIYA-like sequences. In addition to the four reported major segments, several rare segments (e.g., B′, B″ and D′) were defined and 20 different sequence types (e.g., ABD, ABC) were found in our study. A total of 481 (95.6%) strains carried the East Asian type CagA, and the ABD subtypes were most prevalent (82.1%). Only 22 strains carried the Western type CagA, which included AC, ABC, ABCC and ABCCCC subtypes. The CagA-ABD subtype had statistical difference in different geographical regions (P = 0.006). There were seven amino acid polymorphisms in the sequences surrounding the EPIYA motifs, among which amino acids 893 and 894 had a statistical difference with gastric cancer (P = 0.004). Conclusions In this study, 503 CagA sequences were studied and analyzed in depth. In Chinese population, most H. pylori strains were of the CagA-ABD subtype and its presence was associated with gastroduodenal diseases. Amino acid polymorphisms at residues 893 and 894 flanking the EPIYA motifs had a statistically significant association with gastric cancer.

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Diversity of 3’ variable region of cagA gene in Helicobacter pylori strains isolated from Chinese population

10.21203/rs.3.rs-127429/v2 ◽

2021 ◽

Author(s):

Zhijing Xue ◽

Yuanhai You ◽

Lihua He ◽

Yanan Gong ◽

Lu Sun ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Amino Acid ◽

Chinese Population ◽

Statistical Difference ◽

Variable Region ◽

Repeat Region ◽

Geographical Regions ◽

H Pylori ◽

Epiya Motifs

Abstract Background: The cytotoxin-associated gene A (cagA) is one of the most important virulence factors of Helicobacter pylori (H. pylori). There is a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA) repeat region in the C-terminal of CagA protein. This repeat region is thought to play an important role in the pathogenesis of gastrointestinal diseases. The aim of this study was to investigate the diversity of cagA 3’ variable region and the amino acid polymorphisms in the EPIYA segments of the CagA C-terminal region of H. pylori, and their association with gastroduodenal diseases.Methods: A total of 515 H. pylori strains from patients in 14 different geographical regions of China were collected. The genomic DNA from each strain was extracted and the cagA 3’ variable region was amplified by polymerase chain reaction (PCR). The PCR products were sequenced and analyzed using MEGA 7.0 software.Results: A total of 503 (97.7%) H. pylori strains were cagA-positive and 1,587 EPIYA motifs were identified, including 12 types of EPIYA or EPIYA-like sequences. In addition to the four reported major segments, several rare segments (e.g., B’, B’’ and D’) were defined and 20 different sequence types (e.g., ABD, ABC) were found in our study. A total of 481 (95.6%) strains carried the East Asian type CagA, and the ABD subtypes were most prevalent (82.1%). Only 22 strains carried the Western type CagA, which include AC, ABC, ABCC and ABCCCC subtypes. The CagA-ABD subtype had statistical difference in different geographic regions (P = 0.006). There are seven amino acid polymorphisms in the sequences surrounding the EPIYA motifs, among which amino acid residue 893 and 894 had a statistical difference with gastric cancer (P = 0.004).Conclusions: In this study, 503 CagA sequences was studied and analyzed in depth. In Chinese population, most H. pylori strains are of the CagA-ABD subtype and its presence was associated with gastroduodenal diseases. Amino acid polymorphisms at residue 893 and 894 flanking the EPIYA motif had a statistically significant association with gastric cancer.

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Genetic Polymorphisms of miR-146a and miR-27a, H. pylori Infection, and Risk of Gastric Lesions in a Chinese Population

PLoS ONE ◽

10.1371/journal.pone.0061250 ◽

2013 ◽

Vol 8 (4) ◽

pp. e61250 ◽

Cited By ~ 20

Author(s):

Ming-yang Song ◽

Hui-juan Su ◽

Lian Zhang ◽

Jun-ling Ma ◽

Ji-you Li ◽

...

Keyword(s):

Genetic Polymorphisms ◽

Chinese Population ◽

Gastric Lesions ◽

H Pylori

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Diversity of 3’ Variable Region of cagA Gene in Helicobacter Pylori Strains Isolated from Chinese Population

10.21203/rs.3.rs-127429/v1 ◽

2020 ◽

Author(s):

zhijing Xue ◽

Yuanhai You ◽

Lihua He ◽

Yanan Gong ◽

Lu Sun ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Amino Acid ◽

Chinese Population ◽

Statistical Difference ◽

Variable Region ◽

Repeat Region ◽

Geographical Regions ◽

H Pylori ◽

Epiya Motifs

Abstract Background: CagA is one of the most important virulence factors of Helicobacter pylori (H. pylori). There is a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA) repeat region in the CagA 3’ variable region. This repeat region is thought to play an important role in the pathogenesis of gastrointestinal diseases. The aim of this study was to investigate the diversity of CagA 3’ variable region and the amino acid polymorphisms in the EPIYA segments, and their association with gastroduodenal diseases.Methods: A total of 515 H. pylori isolates from patients in 14 different geographical regions of China were collected and the genomic DNA was extracted. The 3’ variable region of the cagA was amplified by polymerase chain reaction (PCR) and then followed by DNA sequencing, and the amino acid sequences were analyzed with MEGA 7.0 software.Results: A total of 503 (97.7%) H. pylori isolates were cagA-positive and 1,587 EPIYA motifs were obtained, including 12 types of EPIYA or EPIYA-like sequences. In addition to the four reported major segments, several rare segments (e.g., B’, B’’ and D’) were defined and 20 different sequence types (e.g., ABD, ABC) were found in our study. A total of 481 (95.6%) strains were East Asian type, most of them were ABD subtype (82.1%). Only 22 strains were Western type, including types AC, ABC, ABCC and ABCCCC. The CagA-ABD subtype had statistical difference in different geographic regions (P=0.006). There are seven amino acid polymorphisms in the sequences surrounding the EPIYA motifs, among which amino acid residue 893 and 894 had a statistical difference with gastric cancer (P=0.004).Conclusions: In this study, 503 CagA sequences was studied and analyzed in depth. In Chinese population, most H. pylori isolates are of the CagA-ABD subtype and its presence was associated with gastroduodenal disease. Amino acid polymorphisms at residue 893 and 894 flanking the EPIYA motif had a statistically significant association with gastric cancer.

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SNP-SNP interactions of three new pri-miRNAs with the target gene PGC and multidimensional analysis of H. pylori in the gastric cancer/atrophic gastritis risk in a Chinese population

Oncotarget ◽

10.18632/oncotarget.8057 ◽

2016 ◽

Vol 7 (17) ◽

pp. 23700-23714 ◽

Cited By ~ 11

Author(s):

Qian Xu ◽

Ye-feng Wu ◽

Ying Li ◽

Cai-yun He ◽

Li-ping Sun ◽

...

Keyword(s):

Gastric Cancer ◽

Atrophic Gastritis ◽

Chinese Population ◽

Target Gene ◽

Multidimensional Analysis ◽

H Pylori

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Association between Helicobacter pylori infection and overweight or obesity in a Chinese population

The Journal of Infection in Developing Countries ◽

10.3855/jidc.6035 ◽

2015 ◽

Vol 9 (09) ◽

pp. 945-953 ◽

Cited By ~ 21

Author(s):

Yan Zhang ◽

Tingting Du ◽

Xi Chen ◽

Xuefeng Yu ◽

Ling Tu ◽

...

Keyword(s):

Helicobacter Pylori ◽

Chinese Population ◽

Statistical Significance ◽

Positive Association ◽

Health Examination ◽

Negative Group ◽

Positive Group ◽

Cardiometabolic Disorders ◽

H Pylori ◽

Overweight Or Obesity

Introduction: Recent studies found that Helicobacter pylori (H. pylori) infection plays a role in cardiometabolic disorders. The objective of this study was to assess the association between H. pylori infection and overweight or obesity in a Chinese population. Methodology: A cross-sectional analysis using data from the subjects who underwent a health examination between January 2010 and June 2012 in the department of comprehensive medicine was performed. Diagnosis of H. pylori infection was achieved using the carbon urea breath test (14C-UBT). The participants were divided into H. pylori infection-positive group and H. pylori infection-negative group by 14C-UBT. Results: A total of 2,050 subjects were enrolled in the study. The H. pylori infection-positive group had significantly higher body mass index (BMI) levels than did the H. pylori infection-negative group (25.32 vs 24.95, p = 0.008). There was a positive association between H. pylori infection and BMI levels (β = 0.30 ± 0.12, p = 0.015). After additional adjustment for white blood cell count (WBCC), the statistical significance disappeared (β = 0.24 ± 0.12, p = 0.053). Furthermore, a positive association between H. pylori infection and overweight/obesity according to different BMI criteria (BMI ≥ 24, BMI ≥ 23) was found. However, the association between H. pylori infection and obesity was consistently significant only based on the Asian criteria (BMI ≥ 27.5), but not significant based on the Chinese criteria (BMI ≥ 28). Conclusion: H. pylori infection was significantly and positively associated with overweight/obesity in a Chinese population.

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