STAT3 and neoplasm: Aberrant STAT3 activation often arises in a paracrine manner from oversupply of growth factors (epidermal growth factor, EGF, hepatocyte growth factor, HGF, transforming growth factor α, TGFα, etc.)and/or inflammatory cytokines (interleukin 6, IL-6, family members, etc.)within the tumor microenvironment.