Metastatic (LY2) and nonmetastatic (B4B8) head and neck squamous cell carcinoma (HNSCC) cell lines were injected into the oral cavity of Stat1 deficient (Stat1<sup>-/-</sup> ) and Stat1 competent (Stat1<sup>+/+</sup> ) mice.
Overexpression of IFNAR1, MX1 and signal transducer and activator of transcription 1 (Stat1) indicated the endogenous IFNα activation in tumour microenvironment, which correlated with immunosuppression status in HNSCC patients.
Since our previous data determined p38 MAPK to be a potent regulator of interleukin-6 (IL-6) and IL-8 expression in permanent head and neck squamous cell carcinoma (HNSCC) cell lines, we investigated the influence of this pathway on STAT3 and STAT1.