STAT3 and cancer: IL6, as a multifunctional pro‐inflammatory cytokine, is an integral component of the intracellular feedback loop between tumor and host immunity, which regulates cancer progression through a variety of mechanisms, including accelerating EMT, stimulating angiogenesis, self‐renewal of CSCs, and facilitating tumorigenesis and increased metastasis [49, 50, 51, 52], and elevation of IL6 levels serves as a trigger of the JAK/STAT3 signaling pathway.