Salivary Immunosuppressive Cytokines IL-10 and IL-13 Are Significantly Elevated in Oral Squamous Cell Carcinoma Patients

Oral squamous cell carcinoma (OSCC) is considered to be one of the most fatal diseases worldwide, owing to its late diagnosis and lack of availability of established reliable biomarkers. The aim of this study was to highlight the significance of immunosuppressive cytokines as potential biomarkers in OSCC. Whole unstimulated saliva was collected from each individual (30 OSCC patients and 33 age- and gender-matched healthy controls). Immunosuppressive cytokines, including IL-4, IL-10, IL-13, and IL-1RA, were evaluated in each sample using Luminex multianalyte profiling (xMAP) technology on BioPlex instrument. Our results showed that all the studied salivary cytokines were raised in OSCC patients as compared to controls, where IL-10 and IL-13 salivary levels showed statistically significant difference (p = .004 and p = .010, respectively). Mean levels of salivary cytokines in three histologically defined OSCC categories, compared employing one-way ANOVA, showed that salivary levels of IL-1RA were highest in patients having poorly differentiated OSCC tumors as compared to those having moderately and well-differentiated tumors (p = .000 and p = .002, respectively). Among OSCC individuals, duration of smokeless tobacco correlated positively with IL-1RA (p = .036). We conclude that salivary levels of immunosuppressive cytokines, IL-4, IL-10, IL-13, and IL-1RA, could prove to be potential biomarkers of OSCC and can be further investigated as markers of early detection and disease progression.