AXL and pancreatic neuroendocrine tumor: Several inhibitors targeting VEGF and other RTK pathways have been tested, including: Brivanib (dual FGF/VEGF- RTKi), which increases the overall survival (OS) of pancreatic neuroendocrine tumors mouse models; dovitinib (VEGF, FGF and PDGFRs- RTKi) that delays tumor growth; and S49076 (MET, AXL, and FGF RTKi) that induces tumor growth arrest in bevacizumab-resistant tumors [47,49,50].