SOCS molecules are negative feedback regulatory proteins of the classical IL-6/STAT3 signaling pathway, and they inhibit the phosphorylation of STAT3 and the formation of dimers or directly inhibit the phosphorylation of JAK, thus negatively regulating the IL-6/STAT3 pathway to inhibit the continuous proliferation and differentiation of cancer cells (34, 35). This evidence concerns the gene STAT3 and cancer.