Meta-analysis of the role of IL-6 rs1800795 polymorphism in the susceptibility to prostate cancer

Abstract

Playing critical roles in immune responses, interleukin-6 (IL-6) has been proposed to be involved in the development of multiple cancers, including prostate cancer. The rs1800795 polymorphism in the promoter of the gene IL-6 can affect the transcription and expression of the gene, becoming a common target in association studies on tumors. We therefore carried out this meta-analysis to further discuss the relationship of this polymorphism with the risk of prostate cancer.Relevant publications were retrieved from the electronic databases. The strength of the correlation between IL-6 rs1800795 polymorphism and prostate cancer risk was evaluated using pooled odds ratios (ORs) with their 95% confidence intervals (95% CIs). Q test was adopted to examine between-study heterogeneity, with P < 0.05 as significant level. Subgroup and meta-regression analyses were conducted to explore potential source of heterogeneity. Sensitivity analysis was implemented to test the statistical stability of the final results. In addition, funnel plot and Egger test were employed to inspect publication bias among included studies.A total of 13 132 cases and 15 282 controls were ultimately incorporated into the present study. Overall estimates revealed no significant relationship between IL-6 rs1800795 polymorphism and prostate cancer risk in total analysis, but a risk-increasing effect of the polymorphism was detected in African-American subgroup under CC versus GG and CC versus GG + GC contrasts (OR 3.43, 95% CI 1.01–11.71; OR 3.51, 95% CI 1.04–11.82) after subgroup analysis by ethnicity.IL-6 rs1800795 polymorphism may enhance the susceptibility to prostate cancer in African-American men.

Increased expression of interleukin-6 gene in gastritis and gastric cancer

“…IL-6 activation of STAT3 seems to influence vital processes of tissue homeostasis maintenance. Thus, IL-6 gene regulates some of the key steps in controlling inflammation and establishes the anti-inflammatory environment (6)(7)(8). In this context, some studies have tried to understand how IL-6 is capable of protecting and resolving inflammation, but can also cause several harmful consequences to the organism, especially in chronic and progressive diseases (24,25).…”

“…However, to develop its functions in the biological control of processes, such as B cell differentiation, apoptosis, and cell proliferation, its membrane receptor (IL-6R) must be present. The IL-6/IL-6R complex activates important signaling pathways in inflammatory and carcinogenic processes (6)(7)(8)(9). When expressed, it may act as an anti-apoptotic factor in esophageal carcinoma cells by activating the STAT3 and JAK signaling pathway (7).…”

Genetic polymorphisms of IL-6 promoter in cancer susceptibility and prognosis: a meta-analysis

“…Several recent meta-analysis have focused on the association between IL-6 promoter polymorphisms and cancer risk. Two meta-analysis showed that rs1800795 polymorphism increased the risk of prostate cancer and cervical cancer [ 108 , 109 ]. Though, the result same with ours, it still exist some problems.…”

Interleukin-6 -174 G/C polymorphism is associated with the risk of basal cell carcinoma in a Chinese Han population

“…And Duan et al reported that the -174 G/C polymorphism was a low-penetrance susceptibility variant for cervical cancer [ 19 ]. In addition, the IL-6 -174 G/C polymorphism reportedly enhances the susceptibility of African American men to prostate cancer [ 20 ].…”