Brief Article
Copyright ©2012 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Sep 21, 2012; 18(35): 4917-4924
Published online Sep 21, 2012. doi: 10.3748/wjg.v18.i35.4917
Inducible nitric oxide synthetase genotype and Helicobacter pylori infection affect gastric cancer risk
Alireza Rafiei, Vahid Hosseini, Ghasem Janbabai, Bahman Fazli, Abulghasem Ajami, Zahra Hosseini-khah, Jeremy Gilbreath, D Scott Merrell
Alireza Rafiei, Bahman Fazli, Abulghasem Ajami, Zahra Hosseini-khah, Faculty of Medicine, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari 48175-1665, Iran
Vahid Hosseini, Department of Internal Medicine, Mazandaran University of Medical Sciences, Sari 48175-1665, Iran
Ghasem Janbabai, Department of Internal Medicine, Imam Hospital, Mazandaran University of Medical Sciences, Sari 48175-1665, Iran
D Scott Merrell, Jeremy J Gilbreath, Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States
Author contributions: Rafiei A and Fazli B designed the study protocol; Hosseini V performed endoscopy and evaluated case findings; Janbabai G performed histopathological examination and staging of the patients; Ajami A and Fazli B performed serology tests; Hosseini-khah Z and Fazli B performed molecular tests and screened patients; Rafiei A and Ajami A did the statistical analysis; Rafiei A, Gilbreath J and Merrell DS analyzed data and wrote the manuscript.
Supported by The Mazandaran University of Medical Sciences, No. 88-512
Correspondence to: Dr. Bahman Fazli, Faculty of Medicine, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, 18KM Khazar Blvd, Khazar Sq., Sari 48175-1665, Iran. falib100@gmail.com
Telephone: +98-151-3543088 Fax: +98-151-3543087
Received: February 28, 2012
Revised: May 15, 2012
Accepted: May 26, 2012
Published online: September 21, 2012
Abstract

AIM: To investigate the association of the inducible nitric oxide synthetase (iNOS) C150T polymorphism with Helicobacter pylori (H. pylori) infection and gastric cancer (GC) risk in Iran.

METHODS: In order to determine whether there was a correlation between iNOS genotype and GC in Iran, we conducted a case-control study using samples from 329 individuals. For each sample, the C150T iNOS polymorphism was genotyped by polymerase chain reaction (PCR) and restriction digestion. Patients were grouped by cancer presence, demographic and behavior characteristics, and H. pylori infection status. Statistical tests were conducted to determine whether any behavioral factors or a particular iNOS genotype was associated with GC in the study population.

RESULTS: In this population, we found that smoking, hot beverage consumption, a familial history of GC and H. pylori infection status were significantly associated with GC development (P = 0.015, P < 0.001, P = 0.0034, and P < 0.015, respectively). The distribution of the C150T iNOS genotypes among the two study groups was not statistically significant alone, but was impacted by H. pylori infection status. When compared to the non-H. pylori infected group, cancer patients who had a heterozygous CT genotype and were also infected with H. pylori were 2.1 times more at risk of developing GC [odds ratio (OR) = 2.1, P = 0.03] while those with a homozygous TT genotype and infected with H. pylori were 5.0 times more at risk of developing GC (OR = 5.0, P = 0.029). In contrast, this association was not seen in patients in the control group.

CONCLUSION: A CT or TT polymorphism at position 150 in the iNOS gene significantly increases the risk of GC and may be a marker for GC susceptibility.

Keywords: Inducible nitric oxide synthetase; Gastric cancer; Helicobacter pylori; Heterozygous CT genotype; Homozygous TT genotype