The JAK-STAT signaling pathway is one of the key mechanisms for cells to respond to external signals, especially cytokines and growth factors, for internal communication. This pathway involves members of the Janus kinase (JAK) and signal transducer and activator of transcription (STAT) protein families. When cytokines or growth factors bind to their specific receptors, the receptors undergo a conformational change, leading to the activation of JAK family kinases on the inner side of the cell membrane. JAK kinases then phosphorylate the receptors, creating binding sites for STAT proteins. The phosphorylated STAT proteins undergo homodimerization or heterodimerization, forming active STAT complexes. These complexes subsequently translocate to the cell nucleus, directly bind to DNA, and regulate the expression of target genes, affecting a variety of biological processes such as cell growth, differentiation, apoptosis, and immune response.