Impact of Interleukin-18 polymorphisms on urothelial cell carcinoma susceptibility in Taiwan
Shian-Shiang Wang, Yen-Chuan Ou, Chen-Li Cheng, Hao-Chung Ho, Kun-Yuan Chiu,,Chung-Kuang Su, Chuan-Shu Chen, Jian-Ri Li, Cheng-Kuang Yang, Cheng-Che Chen, Shun-Fa Yang*
Division of Urology, Department of Surgery, Taichung Veterans General Hospital, Taiwan, Institute of Medicine, Chung Shan Medical University,Taichung, Taiwan*.
Interleukin-18 (IL-18) is an 18-kDa cytokine and has similar structural and functional properties with interleukin-1. IL-18 is produced by various immune and non-immune cells and serum IL-18 level is reported to have prognostic significance in several types of cancers. We explored the effect of IL-18 gene polymorphisms on the susceptibility of urothelial cell carcinoma (UCC) in Taiwan.
Materials and Methods:
We recruited 283 patients (186 men and 97 women, with a mean age of 68.59 years) at Taichung Veterans General Hospital in Taichung, Taiwan. Patients were enrolled as a patient group in 2011–2012. All patients have pathology proved UCC of upper urinary tract or urinary bladder. Meanwhile, during the same study period, 283 age- and gender-matched individuals were enrolled as the controls that entered the physical examination. Personal information and characteristics collected from the study subjects using interviewer administered questionnaires contained questions involving demographic characteristics and the status of cigarette smoking. Medical information for the cases was obtained from their medical records, and included TNM clinical staging, lymph node involvement, and histologic grade.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.
After adjusting for other co-variants, the individuals carrying at least one C allele at rs187238 had a 1.617-fold risk of developing UCC than did wild-type (GG) carriers. Furthermore, the smoking individuals who carried at least one C allele at rs187238 had a 2.760–fold risk of UCC. However, the rs1946518 and rs187238 polymorphisms of the IL-18 gene did not affect tumor stage among the UCC patients..
The rs187238 polymorphic genotypes of IL-18 might contribute to the susceptibility of UCC and the synergic effect of smoking was also demonstrated.