Among them, STAT3 is most closely related to cancer, and its abnormal activation is closely related to the occurrence and development of a variety of human malignant tumors, such as leukemia, lymphoma, prostate cancer, and all kinds of head and neck tumors and gastrointestinal tumors as well as to immune tolerance in the tumor microenvironment [24]. This evidence concerns the gene STAT3 and digestive system neoplasm.