STAT3 and gastric cancer: A high-resolution magnetic tweezer was used in our results to explore binding mechanics between STAT3 and promoter region at single-molecule levels and we found that phosphorylation had an important influence on DNA binding of STAT3, furthermore, STAT3 didn't bind to promoter of miR-193a-3p without ATP which was consistent with our in vitro cell experiments that crosstalk between adipocytes and gastric cancer cells provided amounts of ATP for tumor cells.