STAT3 and squamous cell carcinoma: This mechanism has been described in multiple myeloma, where IL-6 overexpression led to increased JAK/STAT3 activity [52], as well as in squamous cell carcinoma of the head and neck, where elevated levels of transforming growth factor-α (TGF-α) and subsequent STAT3 activation abrogated apoptosis of epithelial cells [53].