Assessment of Interleukin-6 and Interleukin-10 as Serum Biomarkers in a Spontaneous Feline Tumor Model of Head and Neck Squamous Cell Carcinoma (HNSCC)

Introduction: Elevated levels of interleukin (IL)-6 and IL-10 are promising surrogate biomarkers implicated in outcome and survival in HNSCC. Investigation of interleukins in a translational model of HNSCC may elucidate their role. Feline oral squamous cell carcinoma (FOSCC) is an excellent model of advanced stage HNSCC and represents a novel, relevant, and underutilized resource in translational cancer research. Molecular similarities include p53 mutations, COX-2 and EGFR expression, tobacco smoke exposure, and a possible role of papillomavirus. The aim of this study was to characterize serum levels of IL-6 and IL-10 in naturally occurring FOSCC.

Methods: Serum IL-6 and IL-10 levels were measured in 14 cats with naturally occurring FOSCC and 15 control cats (Feline IL-6 and IL-10 DuoSet ELISA, R&D Systems). Data were analyzed using a commercial software system with a Mann-Whitney U test with a P value of <0.05 considered significant.

Results: IL-6 and IL-10 levels in cats with FOSCC (IL-6 median 411.2 pg/mL and IL-10 median 340 pg/mL) were not statistically different from control cats (IL-6 median 951.8 pg/mL and IL-10 median 670 pg/mL).

Conclusions: Serum levels of IL-6 and IL-10 do not appear to be useful biomarkers for FOSCC as a translational model of HNSCC. Limitations of the study include small sample size and lack of controls for the effects of stress and inflammation such as dental disease on circulating cytokine levels. Further investigation is needed to evaluate the prognostic implication of serum interleukin levels in affected cats as well as intratumoral interleukins.