Published online Aug 28, 2020. doi: 10.3748/wjg.v26.i32.4817
Peer-review started: March 12, 2020
First decision: May 15, 2020
Revised: July 2, 2020
Accepted: August 20, 2020
Article in press: August 20, 2020
Published online: August 28, 2020
The development of gastric cancer (GC) is suggested to be related to the interactions between bacterial virulence factors, host genetic factors such as the human leukocyte antigen (HLA) gene, the immune response of the host, and environmental factors. Some of the host factors may be polymorphisms in the host genes such as HLA genes, which regulate the strength of the inflammatory response and influence the probability of a specific clinical outcome.
We seek to determine which HLA class I and II alleles differ in gastrointestinal pathologies such as GC and duodenal ulcer (DU) in Turkey.
We investigated the allele frequencies of HLA class I and II in a patient group [Helicobacter pylori (H. pylori)-positive GC and DU patients] and compared the results to a control group (H. pylori-positive non-ulcer dyspepsia patients and asymptomatic individuals with H. pylori) in terms of CagA+ multiple (≥ 2) EPIYA-C repeats for the first time in a Turkish population.
In this case-control study, amplification of the H. pylori cagA gene and typing of EPIYA motifs were performed by PCR. HLA allele types were identified by sequence-specific oligonucleotide typing kits (HLA-A, HLA-B HLA-C, HLA-DRB1, and HLA-DQA1/B1 kits).
None of the alleles were detected as independent risk factors after multivariate analysis in terms of CagA+ multiple (≥ 2) EPIYA-C repeats. On the other hand, in a multivariate logistic regression with no discriminative criterion, HLA-DQA1*01 [odds ratio (OR) = 1.848], HLA-DQB1*06 (OR = 1.821), and HLA-A*02 (OR = 1.579) alleles were detected as independent risk factors for GC and DU.
We suggest that the association of these alleles with gastric malignancies is not specifically related to cagA and multiple EPIYA C repeats.
Specific HLA alleles maybe related to the gastric malignancies and could be for the indication of GCs in order to scan populations before the development of GC. The alleles may also be cost-effective to find individuals with a higher risk for GC development.