Interleukin-1 gene family polymorphisms from paraffin-embedded archival tissue of Chinese patients with gastric ulcer and gastric cancer.

Background/Aims: Polymorphisms of the interleukin (IL)-1 gene family have been associated with increased risk of gastric ulcer and gastric cancer. The aim of this study was to determine the relationship between single nucleotide polymorphisms (SNPs) in the IL-1 gene family in archival tissue of gastric ulcer and gastric cancer to enable further large scale population investigation in the Chinese Han population from the Wuhan Hubei region. Methodology: DNA was extracted from archival paraffin-embedded tissue blocks of 53 cases with gastric cancer (22 intestinal type, 29 diffuse type, and 2 mixed type) and 34 cases with gastric ulcer. The tissue specimens had been routinely fixed in unbuffered 10% formalin. Genotyping of SNPs IL-1B T-31C, IL-1B C+3954T and IL-1RN T+2018C was performed using Taqman real-time PCR allelic discrimination technology. Results: The frequency of genotype IL-1B-31C/C seems to be increased in patients with gastric cancer (32.1%) when compared to patients with gastric ulcer (11.8%) (P<0.05). Allele IL-1B+3954T/T was not be found in patients with gastric cancer and gastric ulcer. The quality of genomic DNA extracted from the paraffin-embedded, unbuffered formalin-fixed tissue blocks did enable reliable genotyping of all samples. Conclusions: IL-1B-31C/C may be associated with gastric cancer in patients of Chinese Han population. The genotype of IL-1B3954 T/T may protect against gastric cancer and gastric ulcer in Chinese Han population. Unbuffered formalin-fixed, paraffin-embedded gastric tissue from Chinese patients with gastric ulcer and gastric cancer is a valuable source of DNA, suitable for large scale investigation.