STAT3 and cancer: A member of the STAT family, STAT3 has been shown to play a crucial role in modulating the epithelial–mesenchymal transition during cancer metastasis [28], STAT3 activation is associated with cell growth, particularly tumor growth [29], and activated STAT3 can induce the expression of cell-cycle regulators, apoptosis inhibitors, and angiogenesis-inducible factors, which are all key factors in tumorigenesis [30–32,9].