Prognostic significance of interleukin 17 in cancer: a meta-analysis

The prognostic value of Interleukin 17 (IL-17) in cancer patients is currently under debate and remains inconclusive. We performed a systematic review and meta-analysis to evaluate the role of IL-17 as a prognostic marker in cancer. Hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were combined to measure the effective value of IL-17 expression on prognosis. Nineteen eligible studies enrolling 2390 patients were identified. We found expression of IL-17 was not significantly correlated with overall survival (OS) in cancer (HR=1.29, 95% Cl: 0.94-1.76; P=0.12). Furthermore, compared to the data from our analysis that high expression of IL-17 predicted poor OS in both non-small cell lung carcinoma (NSCLC) (HR=2.30; 95% CI: 1.45-3.64; P<0.001; I(2)=0%) and hepatocellular carcinoma (HCC) (HR=2.02; 95% CI: 1.44-2.83; P<0.001; I(2)=0%), high expression of IL-17 was associated with favorable OS in esophageal squamous cell carcinoma (ESCC) (HR=0.63; 95% CI: 0.51-0.79; P<0.001; I(2)=0%). This meta-analysis showed that IL-17 has the potential to become a novel prognostic marker in HCC, NSCLC and ESCC. It could potentially help to monitor patients' prognosis and assess therapeutic efficacy in clinical treatment.