Journal Article

Impact of Interleukin-18 Polymorphisms -607A/C and -137G/C on Oral Cancer Occurrence and Clinical Progression

Hsieh, Yi-Hsien, Lin, Chiao-Wen, Yang, Shun-Fa, Tsai, Hsiu-Ting, Hsin, Chung-Han, Chen, Mu-Kuan, Tang, Chih-Hsin

2013

Overview

The purpose of this study was to identify gene polymorphisms of interleukin-18 (IL-18) -607A/C and -137G/C specific to patients with oral cancer susceptibility and clinicopathological status. A total of 1,126 participants, including 559 healthy people and 567 patients with oral cancer, were recruited for this study. Allelic discrimination of -607A/C (rs1946518) and -137G/C (rs187238) polymorphisms of the IL-18 gene was assessed by a real-time PCR with the TaqMan assay. There was no significant association between IL-18 -607A/C polymorphism and oral cancer risk. However, among alcohol consumers, people with A/A homozygotes of IL-18 -607A/C polymorphism had a 2.38-fold (95% CI=1.17-4.86; p=0.01) increased risk of developing oral cancer compared with those with C/C homozygotes. The participants with G/C heterozygotes of IL-18 -137 polymorphism had a 1.64-fold (95% CI: 1.08-2.48; p=0.02) increased risk of developing oral cancer compared with those with G/G wild type homozygotes. Both sets of statistics were determined after adjusting for confounding factors. Among people who had exposure to oral cancer-related environmental risk factors such as areca, alcohol, and tobacco consumption, the adjusted odd ratios and 95% confidence intervals were increased to a 2.02-fold (95% CI=1.01-4.04; p=0.04), 4.04 (95% CI=1.65-9.87; p=0.002) and a 1.66-fold (95% CI=1.00-2.84; p=0.05) risk of developing oral cancer. However, patients with G/C alleles of IL-18 -137 were correlated with a lower clinical stage (AOR=0.59; 95% CI=0.39-0.89; p=0.01), smaller tumor size (AOR=0.56; 95% CI=0.35-0.87; p=0.01), and non-lymph node metastasis (AOR=0.51; 95% CI=0.32-0.80; p=0.003). IL-18 -137 G/C gene polymorphism may be a factor that increases the susceptibility to oral cancer, as well as a protective factor for oral cancer progression. The interactions of gene to oral cancer-related environmental risk factors have a synergetic effect that can further enhance oral cancer development.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Alcohol / Alcohol Drinking - adverse effects / Alcohol Drinking - genetics / Alcohol use / Alcoholic beverages / Apoptosis / C gene / Cancer / Cancer research / Cell cycle / Confidence intervals / Cytokines / Development and progression / Disease Progression / Disease susceptibility / Environmental risk / Female / Gene expression / Gene polymorphism / Gene-Environment Interaction / Genes / Genetic aspects / Genetic polymorphisms / Genetic Predisposition to Disease / Health aspects / Health risk assessment / Health risks / Heterozygotes / Homozygotes / Hospitals / Humans / Interleukin 18 / Interleukin-18 - genetics / Interleukins / Lymph nodes / Male / Medicine / Metastases / Metastasis / Middle Aged / Mouth cancer / Mouth Neoplasms - genetics / Oral cancer / Otolaryngology / Patients / Polymorphism / Polymorphism, Genetic / Population / Risk analysis / Risk Factors / Smoking - adverse effects / Smoking - genetics / Tobacco