STAT3 and head and neck squamous cell carcinoma: IL‐6 also induces EMT in ovarian cancer cells, similarly via the JAK2/STAT3 signaling pathway (Colomiere et al., 2009) (Fig. 2), in head and neck squamous cell carcinoma cells (Wu et al., 2016a), in gastric cancer cells (Chen et al., 2017), and in uterine cervix cancer cells (in a STAT3‐Slug‐dependent way) (Miao et al., 2014).