Investigation of salivary interleukin-17 in patients with oral squamous cell carcinoma Vol. 11 No. 06 (2025

Background: Oral squamous cell carcinoma (OSCC) is a common aggressive cancer with few noninvasive biomarkers for early detection. A-17͏, a pro-inflammatory cytokine involved in tumor progression could be used as a salivary biomarker for the diagnosis and monitoring of OSCC. Objectives: To measure and compare levels of IL-17 in saliva of OSCC patients and healthy controls as well as to evaluate the expression of IL-17 in relation to tumor location and patient gender. Methods: In the Medical City Complex, Baghdad, Iraq a case-control study was carried out between March 2024 and January 2025. In total, 90 participants were enrolled; patients and controls matched for age and gender with 55 OSCC patients and 35 healthy controls. Clinically and histopathologically confirmed OSCC. Unstimulated saliva samples were collected under standardized conditions and analyzed for IL-17 concentration by using a commercially available ELISA kit. Statistical analyses were also carried out to compare IL-17 levels between groups as well as associations with tumor location and gender. Results: The OSCC patients had significantly higher salivary IL-17 levels (86.22 ± 19.56 pg/mL) as compared to healthy controls (44.12 ± 13.24 pg/mL) (T = 5.87, p = 0.022). Tumor location showed a significant association with the values of IL-17 (F = 9.12, p = 0.004). The highest values were for tumors in buccal mucosa, gingiva, and tongue; the lowest was for tumors in the palate. No significant difference was noted between males and females regarding IL-17 levels (p=0.11). Conclusion: High levels of salivary IL-17 are linked to OSCC and its level changes with the site of the tumor lesion, which suggests IL-17 as a good easy test for finding and watching OSCC. Being male or female does not seem to affect IL-17 levels.