After substratification of the subjects according to their smoking, alcohol consumption, and areca chewing status, the genotype distribution of the <i>IL-18</i>-607 polymorphism was found to be different only among nonsmokers between the NPC and control subgroups.
The results indicate that the IL-18-137 G/C polymorphism is associated with HNC risk, especially nasopharyngeal cancer, in Asian populations and, when using PCR-RFLP, CXCL8 -251 A/T polymorphisms play a complex role in HNC development.
The meta-analysis results suggest that IL-18 gene promoter -607 C>A polymorphism is significantly associated with overall cancer risk, especially in nasopharyngeal carcinoma and gastrointestinal cancer; and the -137 G>C polymorphism is associated with increased overall cancer risk in Asian populations and also significantly increases the risk of nasopharyngeal carcinoma.
We provide evidence that the -137G>C polymorphism in IL-18 promoter region significantly increases cancer risk in Asian population but not in Caucasian population, and the variant -137C allele is associated with increased risk of nasopharyngeal carcinoma.
The present meta-analysis suggests that the -607C/A polymorphisms in IL-18 gene promoter is associated with a significantly increased risk of cancer, especially for nasopharyngeal carcinoma and esophageal cancer and in Asian population.
Variations in the DNA sequence of the IL-18 gene promoter may lead to altered IL-18 production and/or activity, so this can modulate an individual's susceptibility to NPC.