PTP1b, which influences JAK-STAT signaling to induce oncogenesis in breast cancer, can also promote breast cancer by dephosphorylating the inhibitory Tyr527 phosphorylation site and activating Src and downstream signaling pathways, which enhances ERbB2 receptor signaling (Figure 2B) [17,18,53]. The gene discussed is PTPN1; the disease is breast cancer.