The contribution of interleukin-8 genotypes and expression to nasopharyngeal cancer susceptibility in Taiwan

Medicine (Baltimore). 2018 Sep;97(36):e12135. doi: 10.1097/MD.0000000000012135.

Abstract

The incidence rate of nasopharyngeal cancer (nasopharyngeal carcinoma [NPC]) is much higher in Southeast Asia than in western countries. Interleukin-8 (IL-8), a chemokine produced by macrophages, epithelial cells, airway smooth muscle cells, and endothelial cells, is an important immuno-mediator in the development and progression of many types of cancer. Genetic variations in IL-8 have been associated with the risks of NPC and other cancers. In the current study, we evaluated the role of IL-8 in NPC at the levels of DNA, RNA, and protein in a Taiwanese population. First, in a case-control study, 176 NPC patients and 352 cancer-free controls were genotyped, and the associations of IL-8 T - 251A, C + 781T, C + 1633T, and A + 2767T polymorphisms with NPC risk were evaluated. Second, the NPC tissue samples were assessed for their IL-8 mRNA and protein expression by real-time quantitative reverse transcription polymerase chain reaction (PCR) and Western blotting, respectively. Regarding the IL-8 promoter T - 251A, the TA and AA genotypes were associated with significantly decreased risks of NPC compared with the wild-type TT genotype (adjusted odds ratio = 0.61 and 0.52, 95% confidence interval = 0.47-0.93 and 0.37-0.91, P = .0415 and .0289, respectively). The mRNA and protein expression levels for NPC tissues revealed no significant associations among the 20 NPC samples with different genotypes. These findings suggest that IL-8 may play an important role in the carcinogenesis of NPC in Taiwan.

MeSH terms

  • Asian Continental Ancestry Group / genetics
  • Carcinoma / ethnology
  • Carcinoma / genetics*
  • Carcinoma / metabolism
  • Carcinoma / pathology
  • Case-Control Studies
  • Female
  • Gene-Environment Interaction
  • Genetic Association Studies
  • Genetic Predisposition to Disease*
  • Humans
  • Interleukin-8 / genetics*
  • Interleukin-8 / metabolism
  • Male
  • Middle Aged
  • Nasopharyngeal Carcinoma
  • Nasopharyngeal Neoplasms / ethnology
  • Nasopharyngeal Neoplasms / genetics*
  • Nasopharyngeal Neoplasms / metabolism
  • Nasopharyngeal Neoplasms / pathology
  • Promoter Regions, Genetic
  • RNA, Messenger / metabolism
  • Taiwan

Substances

  • CXCL8 protein, human
  • Interleukin-8
  • RNA, Messenger