STAT3 and gastric cancer: Previous studies clearly demonstrated anticancer effects of plumbagin in various types of gastric cancer cell lines, including AGS, SGC-7901, and MKN-28 which were found to be due to the induction of apoptotic cell death either through suppression of Akt and STAT3 phosphorylation [31] or inhibition of NF-κB signaling pathway [32].