Direct determination of Helicobacter pylori vacA genotypes and cagA gene in gastric biopsies and relationship to gastrointestinal diseases

CONTEXT AND OBJECTIVE: The virulence of Helicobacter pylori (HP) in gastroduodenal disease is related to pathogenicity islands (cagPAI) present in some strains. Infection with cagPAI induces IL-8 secretion, increases epithelial cell proliferation and may be important in carcinogenesis. Our objective was to detect HP and the cagA gene (cagPAI marker) by polymerase chain reaction (PCR) and to correlate these results to histological findings, epithelial cell proliferation and apoptosis. DESIGN AND SETTING: Retrospective, at the Surgical and Molecular Pathology Laboratory, Hospital Sírio-Libanês. METHODS: DNA samples isolated from 164 gastric biopsies were used for HP detection by PCR. cagPAI+ was identified in HP+ cases by cagA gene amplification. All cases were submitted to immunohistochemistry to evaluate cell proliferation, and TUNEL to detect apoptosis. Statistical analysis was performed to compare results. RESULTS: HP was detected in 67.7% of the patients, with good correlation between HP infection and moderate to severe gastritis, gastric ulcer and MALT lymphoma. There was a correlation between cagPAI+ strains and severe gastric diseases including cancer. The risk of gastric ulcer, adenocarcinoma and MALT lymphoma was 8.8 times higher for cagPAI+ patients. cagPAI+ infection was related to higher proliferation rates. The proliferation/apoptosis index was significantly higher for cagPAI+ patients. CONCLUSION: Cell growth deregulation in cagPAI+ patients could be demonstrated by the difference in the proliferation index. We believe that this explains the carcinogenic role of Helicobacter pylori.

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Genotyping of the Helicobacter pylori cagA Gene Isolated From Gastric Biopsies in Shiraz, Southern Iran: A PCR-RFLP and Sequence Analysis Approach

Jundishapur Journal of Microbiology ◽

10.5812/jjm.30046 ◽

2016 ◽

Vol 9 (4) ◽

Cited By ~ 2

Author(s):

Afsaneh Moaddeb ◽

Mohammad Reza Fattahi ◽

Roya Firouzi ◽

Abdollah Derakhshandeh ◽

Shohreh Farshad

Keyword(s):

Helicobacter Pylori ◽

Sequence Analysis ◽

Analysis Approach ◽

Caga Gene ◽

Southern Iran ◽

Pcr Rflp ◽

Gastric Biopsies

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Determination of Helicobacter pylori vaca genotypes and caga gene in relationship to gastroduodenal disease in South India

The American Journal of Gastroenterology ◽

10.1016/s0002-9270(03)01622-8 ◽

2003 ◽

Vol 98 (9) ◽

pp. S283

Author(s):

M HABEEB

Keyword(s):

Helicobacter Pylori ◽

South India ◽

Caga Gene ◽

Gastroduodenal Disease

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Determination of Helicobacter pylori virulence-associated genes in duodenal ulcer and gastric biopsies

Medical Journal of the Islamic Republic of Iran ◽

10.14196/mjiri.31.95 ◽

2017 ◽

Vol 31 (1) ◽

pp. 555-559 ◽

Cited By ~ 3

Author(s):

Yasaman Saeidi ◽

Abazar Pournajaf ◽

Mehrdad Gholami ◽

Meysam Hasannejad-Bibalan ◽

Sajjad Yaghoubi ◽

...

Keyword(s):

Duodenal Ulcer ◽

Helicobacter Pylori ◽

Gastric Biopsies

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Analysis of the Carcinogenic Potential of Helicobacter Pylori Based on Determination of the Degree of Phosphorylation of the Caga Protein Bacteria

Health and Ecology Issues ◽

10.51523/2708-6011.2018-15-4-17 ◽

2018 ◽

pp. 86-93

Author(s):

E. V. Voropaev ◽

O. V. Osipkina ◽

O. Yu. Baranov ◽

A. A. Zyatkov ◽

N. A. Bonda ◽

...

Keyword(s):

Helicobacter Pylori ◽

Risk Groups ◽

Gastrointestinal Diseases ◽

Genetic Method ◽

Caga Protein ◽

Carcinogenic Potential ◽

The Republic ◽

Epiya Motifs

The developed molecular and genetic method for analysis of the carcinogenic potential of Helicobacter pylori based on determining the degree of phosphorylation of the cytotoxin-associated protein of the bacterium (CagA) has been presented. The degree of phosphorylation of CagA protein of Helicobacter pylori is estimated by determining the number and type of so-called EPIYA (Glu-Pro-Ile-Tyr-Ala) motifs at the carboxyl end of the CagA protein region using PCR (polymerase chain reaction) and sequencing of the CagA gene locus. The proposed method can be used to form groups of patients who need additional examination and follow-up observation for the purpose of early prediction of pathological conditions associated with the infectious process caused by Helicobacter pylori strains dominating in the Republic of Belarus. The determination of the number and type of EPIYA motifs can be used as an additional criterion for detection of risk groups for gastrointestinal diseases.

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Determination of Helicobacter pylori Virulence Genes in Gastric Biopsies by PCR

ISRN Gastroenterology ◽

10.1155/2013/606258 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 8

Author(s):

Tamer Essawi ◽

Wail Hammoudeh ◽

Israr Sabri ◽

Walid Sweidan ◽

Mohammad A. Farraj

Keyword(s):

Helicobacter Pylori ◽

Virulence Genes ◽

Gastric Biopsy ◽

Strong Indication ◽

Specific Primers ◽

Biopsy Specimens ◽

Pcr Identification ◽

Gastric Biopsies ◽

H Pylori

Aim. The aim of this study was to identify the presence of H. pylori in biopsy specimens from symptomatic patients by PCR. In addition, the rate of cagA, vacA, iceA1, and iceA2 virulence genes was determined. Materials and Methods. One hundred antral gastric biopsy specimens were collected during endoscopy from patients suffering from gastroduodenal symptoms. The samples were collected by the gastroenterologists in their own clinics in Ramallah, Palestine. DNA was extracted from the biopsies and subsequently used for PCR identification of H. pylori and the virulence genes using specific primers. Results. The rate of positive H. pylori in the collected biopsies was 44%. The rates of the virulence genes in this sample: cagA, vacA, iceA1, and iceA2 were 65.9%, 40.9%, 63.6%, and 84.1%, respectively. Conclusion. The iceA2 gene was the most frequent in this study. Much research is necessary to determine the presence of an association of this gene with gastric pathology. Variation in the rates of the iceA gene in different countries is a strong indication of its geographical distribution. This study would provide important information regarding the prevalence of virulence genes (vacA, cagA, iceA1, and iceA2) in H. pylori strains in the sample tested in this country.

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Helicobacter Pylori Variants with ABC-Type Tyrosine Phosphorylation Motif in Gastric Biopsies of Ghanaian Patients

BioMed Research International ◽

10.1155/2021/6616059 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Emmanuel A. Tagoe ◽

Gordon A. Awandare ◽

Osbourne Quaye ◽

Richard H. Asmah ◽

Timothy N. Archampong ◽

...

Keyword(s):

Amino Acids ◽

Helicobacter Pylori ◽

Amino Acid ◽

Tyrosine Phosphorylation ◽

Gastric Disease ◽

Rrna Gene ◽

Caga Gene ◽

Caga Protein ◽

Gastric Biopsies ◽

H Pylori

Background. Helicobacter pylori pathogenicity and disease severity are determined by the tyrosine phosphorylation motifs of CagA protein. This study is aimed at detecting the presence of H. pylori and identifying the CagA tyrosine phosphorylation motifs in Ghanaian patients. Material and Methods. A total of 94 archival genomic DNA samples from gastric biopsies were used for the study, and H. pylori was detected by amplifying the 16S rRNA gene. The 3 ′ -end variable region of the cagA gene was amplified, and the entire 3 ′ -end was sequenced and translated into amino acids. Results. H. pylori was detected in 53.2% (50/94) of the samples, and all the detected bacteria harboured the cagA gene. Two variants of the bacteria were identified based on the size of the amplified cagA gene: 207 bp and 285 bp. The 207 bp and 285 bp variants accounted for 74% and 22%, respectively, and 4% showed both fragments. Translated amino acid sequence of the cagA gene showed EPIYA-A, EPIYA-B, and EPIYA-C (ABC type) motifs, indicating the Western variant. The CagA protein C-terminal showed insertion of amino acids in the sequence flanking the EPIYA-A motif at the N-terminal and a complete deletion of the EPIYA-CC and EPIYA-CCC motifs together with the flanking sequences. Conclusions. H. pylori identified were Western variant (ABC type) with unique amino acid insertions, suggesting unique variants in Ghanaian patients. Further investigation is however required to understand the role of the molecular diversity of the variant in gastric disease outcome.

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Association of Helicobacter pylori restriction endonuclease-replacing gene, hrgA with overt gastrointestinal diseases

Arquivos de Gastroenterologia ◽

10.1590/s0004-28032008000300011 ◽

2008 ◽

Vol 45 (3) ◽

pp. 225-229 ◽

Cited By ~ 1

Author(s):

Manoj G ◽

Santosh K. Tiwari ◽

Vishwas Sharma ◽

Mohammed Aejaz Habeeb ◽

Aleem A. Khan ◽

...

Keyword(s):

Helicobacter Pylori ◽

Surrogate Marker ◽

Gastrointestinal Diseases ◽

Histopathological Analysis ◽

Caga Gene ◽

Oligonucleotide Primers ◽

New Genes ◽

Significant Difference ◽

The Status ◽

H Pylori

BACKGROUND and AIM: Helicobacter pylori has been proven to be responsible for causing various gastrointestinal disorders including gastric adenocarcinoma. Several genes of pathogen (the genes of the cag-PAI, vacA, iceA, and babA) either in combination or independently have been reported to significantly increase the risk of ulceration/gastric carcinoma, with the cagA gene having the strongest predictive value. Pursuit to identify new genes which could serve as a marker of overt disease progression, lead to the discovery of hrgA gene. METHODS: Fifty-six indigenous strains of H. pylori from subjects with various gastric disorder were screened to assess the status of hrgA gene along with the cagA gene using simple polymerase chain reaction using specific oligonucleotide primers. Post-amplification, amplicons were subjected for sequencing to identify any strain specific variations in sequences from the H. pylori isolated from different disease manifestations. Histopathological analysis was done to ascertain any significant change in the histological scores of subjects infected with cagA+/hrgA+ and cagA-/hrg+ strains. RESULTS: All the 56 (100%) subjects amplified with the oligonucleotide primers specific to hrgA gene, whereas 81.71% subjects showed the presence of cagA gene. Sequencing of the amplimers showed 99% homology. Histology of the cagA+/hrgA+ and cagA-/hrg+ subjects did not show any significant difference. CONCLUSION: hrgA gene of Helicobacter pylori is not a ideal surrogate marker for identifying individuals with higher risk of developing overt gastro-duodenal diseases such as neoplasia of the stomach.

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