STAT3 and cancer: IL-6 has can have several cancer-stimulatory effects, many of which are driven by activation of the janus kinase (JAK)-signal transducer and activator or transcription (STAT)3 signaling pathway, which in turn triggers the transcription of a sequence of genes that are responsible for cell proliferation, apoptosis inhibition, cell cycle progression and modulation of the extracellular matrix (39, 40).