CSF1R and neoplasm: For example, in mouse models of lung squamous cell carcinoma and colon cancer, combining the CSF-1R kinase inhibitor PLX3397 with PD-1 inhibitors not only reduced M2 macrophage numbers but also increased CD8+ T cell infiltration, significantly enhancing the anti-tumor efficacy of PD-1/PD-L1 immunotherapy​ (203, 204).