STAT3 and cancer: The role of STAT3 in tumor formation and progression has been extensively studied in many human cancers (Kusaba et al, 2005; Diaz et al, 2006; Banerjee et al, 2016; Li et al, 2019; Susman et al, 2019; Marginean et al, 2021), including HNSCC (Mali, 2015; Geiger et al, 2016).