IL-16 Up-Regulation is Associated with Epithelial Ovarian Cancer Progression and Poor Prognosis in Patients

<b>Objective:</b> IL-16 has been described as a chemoattractant that activates macrophages, CD4+ T cells, eosinophils, dendritic cells, and monocytes, thus activating the secretion of inflammatory cytokines, including IL-15, IL-1β, and TNF-α. The present study aimed to investigate the IL-16 expression in the serum and elucidate IL-16 significance in the clinical assessment of epithelial ovarian cancer (EOC).<b>Methods:</b> The study adopted an enzyme-linked immunosorbent assay (ELISA) to analyze the expressions of IL-16 in the serum derived from 80 EOC patients and 80 age-matched healthy controls. The association of IL-16 levels with EOC patients' prognosis and clinical factors were determined. The receiver operator characteristic (ROC) analysis was done to determine the accuracy of serum IL-16 in EOC diagnosis.<b>Results:</b> EOC patients demonstrated significantly increased serum IL-16 levels compared to the controls (192.4 ±54.27 pg/mL versus 90.5±41.27 pg/mL, <i>P</i><0.001, respectively). Elevated IL-16 levels in the serum were remarkably linked with tumor size (<i>P</i>=0.001), FIGO (International Federation of Gynecology and Obstetrics) stage (<i>P</i>=0.001), recurrence (<i>P</i>=0.039), and metastasis of lymph node (P=0.029). Analysis of the Kaplan-Meier survival curve confirmed elevated IL-16 levels in serum is directly associated with poor overall survival (OS) (<i>P</i>=0.032) and progression-free survival (<i>P</i>=0.041). Assessment of univariate and multivariate results demonstrated IL-16 serum levels (HR: 2.996, 95%CI:1.313-4.231, <i>P</i>=0.006) were the independent EOC patients' prognostic factors. Analyses of the ROC curve confirmed AUC of 0.781, 95% CI:0.639-0.923, <i>P</i><0.001.<b>Conclusion:</b> Elevated IL-16 serum levels are linked with poor prognosis in EOC patients, and IL-16 might be a promising biomarker for the prognosis of EOC among patients.