Impact of interleukin-8 gene polymorphisms and environmental factors on oral cancer susceptibility in Taiwan

Oral Diseases (2012) 18 , 307–314 Objectives: Interleukin‐8 (IL‐8), which is an angiogenic chemokine with a high expression level in tumor tissues, plays important roles in developing many human malignancies including oral squamous cell carcinoma (OSCC). This study was designed to examine the association of IL‐8 gene polymorphisms with the susceptibility and clinicopathological characteristics of OSCC. Methods: A total of 270 patients with OSCC and 350 healthy control subjects were recruited. Four single nucleotide polymorphisms (SNPs) of IL‐8 genes were analyzed using polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) genotyping analysis. Results: Results showed that four IL‐8 SNPs (?251 T/A, +781 C/T, +1633 C/T, and +2767 A/T) were not associated with oral cancer susceptibility as well as clinicopathological parameters. But among 345 smokers, IL‐8 polymorphisms carriers with betel quid chewing were found to have a 17.41‐ to 23.14‐fold risk to have oral cancer compared to IL‐8 wild‐type carriers without betel quid chewing. Among 262 betel quid chewers, IL‐8 polymorphisms carriers with smoking have a 10.54‐ to 20.44‐fold risk to have oral cancer compared to those who carried wild type without smoking. Conclusions: Our results suggest that the combination of IL‐8 gene polymorphisms and environmental carcinogens might be highly related to the risk of oral cancer.