STAT3 and cancer: Among them curcumin, a natural polyphenol extracted from Curcuma longa L., has been shown to have pleotropic anti-cancer properties (anti-oxidant, anti-inflammatory, anti-proliferative) inhibiting multiple targets and molecular pathways such as NF-kB, STAT3, MAPK, PTEN, P53, AKT/mTOR, VEGF and microRNAs (miRNA) network involved in cancer pathogenesis [9, 11, 34, 35].