JAK2 and breast cancer: After Jak2 is activated, it can promote the tyrosine phosphorylation of Stat3 into the nucleus and then specifically bind to the target promoter to promote the expression and transcription of the target genes related to the occurrence of BC, such as target genes associated with cell proliferation, survival, apoptosis, invasion, metastasis, and angiogenesis [25,39] About 70% of BC tumors show continuous Stat3 activation, and most of them are TNBC [40,41].