Genetic polymorphisms of TNF-α and IL-6 and their correlations with susceptibility to colorectal cancer among Chinese Han people in Shandong province / 中华微生物学和免疫学杂志

ABSTRACT

Objective To study the correlations between genetic polymorphisms of TNF-α as well as IL-6 and susceptibility to colorectal cancer among Chinese Han people in Shandong province.Methods Single nucleotide polymorphisms (SNPs) of TNF-α-238G/A,-308G/A and IL-6-174G/C,-572G/C,-597G/A in 490 patients with colorectal cancer were analyzed by using gene chip.Concentrations of TNF-α and IL-6 in serum samples were measured by ELISA.A case-control study was conducted to analyze the correlations between SNPs of TNF-α-238G/A,-308G/A as well as IL-6-174G/C,-572G/C,-597G/A and susceptibility to colorectal cancer.Chi-square test or t test was used for statistical analysis.Relative risks were estimated based on the values of odds ratio (OR) and 95% confidence interval (95%CI).Results The frequency of TNF-α-308AA in patients with colorectal cancer was significantly higher than that in healthy subjects (x2 =6.15, P<0.05, OR=2.08, 95%CI=1.17-3.71), while the frequency of IL-6-572CC in patients with colorectal cancer was significantly lower than that in healthy subjects (x2 =4.97, P<0.05, OR=0.73, 95%CI=0.55-0.96).The frequency of TNF-α-308AA in patients with colon cancer (OR=2.31, 95%CI=1.17-4.55), tubular adenocarcinoma (OR=2.32, 95%CI=1.28-4.21), high (OR=2.05, 95%CI=1.01-4.15) or moderately differentiated adenocarcinoma (OR=5.88, 95%CI=1.79-19.30) was significantly higher than that in healthy subjects.The levels of serum TNF-α in TNF-α-308AA carriers with colorectal cancer were significantly higher than those in TNF-α-308G carriers with colorectal cancer (t=2.13, P<0.05) as well as those in healthy TNF-α-308AA carriers (t=2.13, P<0.05).The levels of serum IL-6 in colorectal cancer group were significantly higher than those in control group (t=6.74, P<0.001).Conclusion The SNPs of TNF-α-308 and IL-6-572 are associated with the occurrence and development of colorectal cancer in Chinese Han people in Shandong province.