STAT3 and cancer: Recent studies have demonstrated that TECs augment proinflammatory cytokines (tumor necrosis factor‐α [TNF‐α], interleukin‐6 [IL‐6], IL‐8, etc.)of cancer cells, which in turn activates nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB) and signal transducer and activator of transcription 3 (STAT3) signaling in cancer cells, and increase invasiveness in vitro [12].