STAT3 and cancer: VEGF and bFGF are known to be involved in endothelial cell proliferation, extracellular matrix degradation, endothelial cell migration, and modulation of junctional adhesion molecules; both have been described as the leading mediators of angiogenesis that can be upregulated by activated STAT3 in glioblastoma stem cells68, papillary thyroid cancer69, and colorectal cancer70, thereby promoting the formation of new blood vessels and development of cancer.