PTPRO and breast cancer: In addition, expression of protein tyrosine phosphatase receptor type O (PTPRO), a multitargeted negative regulator of VEGF-A, PDGF and FGF receptor 1 (FGFR1), also prevented PMN formation and lung metastasis in the mouse breast cancer cell line Py8119275 by attenuating tumor-associated angiogenesis, inducing the apoptosis and necrosis of tumor cells, and mediating M1-like macrophage polarization.276