Significant Contribution of Interleukin-18 Genotypes to Lung Cancer Risk in Taiwanese.

ABSTRACT

BACKGROUND/AIM: The elevated expression of interleukin-18 (IL-18) among lung cancer patients raised our curiosity to examine the role of IL-18 genotypes in lung cancer. MATERIALS AND METHODS: IL-18 -656 (rs1946519), -607 (rs1946518), and -137 (rs187238) genotypes of 358 lung cancer cases and 716 controls were determined via the PCR-RFLP methodology. RESULTS: The distributions of genotypic and allelic frequencies of IL-18 -607, but not those of -656 or -137, were differentially distributed between cases and controls. IL-18 -607 AC and CC genotypes were both lower (45.8% and 16.2%) in lung cancer patients compared to controls (51.4% and 24.7%). In addition, IL-18 -607 AC and CC genotypes were of significantly lower percentages both among non-smokers and smokers. Otherwise, no differential distribution was found regarding IL-18 -656 or -137. CONCLUSION: IL-18 -607 C allele can serve as a protective predictor for lung cancer risk in Taiwanese.