IL6 and cancer: IL-6 represents a keystone cytokine in infection, cancer, and inflammation, which can be produced by multiple cell types in the tumor microenvironment, leading to JAK/STAT3 signaling activation in both tumor cells and tumor‐infiltrating immune cells, and promoted the proliferation, survival, invasiveness, and metastasis of tumor cells, while strongly suppressing the anti-tumor immune response7,8.