Analysis of the correlation between inflammatory cytokines and glioblastoma: A Mendelian randomization study

Epidemiological studies have demonstrated that inflammatory cytokines are associated with cancer development. However, the causal relationship between inflammatory cytokines and glioblastoma remains unclear. We used a two-sample Mendelian randomization approach to determine the potential causal effects of inflammatory cytokines on glioblastoma. Genome-wide association study summary statistics for 41 inflammatory cytokines were obtained from the University of Bristol database, and 91 inflammatory cytokines were acquired from the genome-wide association study catalog database. Genetic data on glioblastoma were downloaded from the FinnGen consortium (R10). Mendelian randomization analysis and Bayesian weighted Mendelian randomization analysis were performed to investigate the causal relationship between inflammatory cytokines and glioblastoma risk. A combination of Mendelian randomization (MR)-Egger, MR-Pleiotropy Residual Sum and Outliers, and Radial MR methods was employed to assess horizontal pleiotropy, which is a potential bias in MR studies. The Cochran Q test was used to quantify the degree of heterogeneity. Finally, we conducted a comprehensive meta-analysis to confirm the robustness of our findings. Increased levels of tumor necrosis factor β (odds ratio [OR] = 1.597, 95% CI: 1.143-2.230, P = .006) and interleukin-10 (OR = 1.452, 95% CI: 1.059-1.992, P = .021) were associated with an increased risk of glioblastoma. Conversely, higher levels of circulating fibroblast growth factor 21 (OR = 0.456, 95% CI: 0.276-0.754, P = .002) and macrophage inflammatory protein 1a (OR = 0.743, 95% CI: 0.558-0.990, P = .042) were associated with a decreased risk of glioblastoma. No significant causal effect on inflammatory cytokines from glioblastoma was detected, and no significant heterogeneity in instrumental variables or horizontal pleiotropy was observed. Our findings indicate that specific inflammatory cytokines may play a role in glioblastoma development, acting as either protective factors or risk factors. This offers valuable insights into the disease mechanism and suggests that targeting these cytokines could be a potential strategy for glioblastoma prevention and treatment.