PDCD1 and cancer: It has been shown that Sitravatinib, a broad-spectrum tyrosine kinase inhibitor (TKI) targeting MET, TAM, and members of VEGFR, platelet-derived growth factor receptor (PDGFR), and Eph families is highly effective in various cancer models, including CT1B-A5, an isogenic pancreatic cancer cell line, that could be partially attributed to altering the TME and restoring the efficacy of immune checkpoint blockade (PD-1) (99).