Immunohistochemical expression of interleukin‐4, ‐6, ‐8, and ‐12 in inflammatory cells in surrounding invasive front of oral squamous cell carcinoma

BACKGROUND: Cytokines play important roles in the diverse interactions between tumor microenvironment and malignant cells. This study evaluated the association of interleukin (IL)-4, -6, -8, and -12 expressions and clinicopathologic parameters of 35 primary oral squamous cell carcinomas (OSCCs). METHODS: Patients were staged according to the TNM clinical staging. Malignancy grading of invasive front was evaluated in hematoxylin-eosin (H&E)-stained slides. Immunohistochemical technique was performed on frozen tissue sections. Association between clinicopathologic parameters and IL expression were analyzed using nonparametric Kruskal-Wallis (alpha = 0.05) and Mann-Whitney U tests, with Bonferroni correction. Correlations between interleukins were analyzed by the Spearman coefficient. RESULTS: Expression of ILs was verified in all samples; however, this finding was not related to clinicopathologic parameters. It was not the observed correlation between ILs. CONCLUSIONS: Expression of IL-4, -6, -8, and -12 in the invasive front of OSCC is not involved with the clinicopathologic parameters of the disease.