AXL and neoplasm: AXL expression is linked to the regulation of stem cell genes, metastatic genes, and enhanced tumor progression through increased cellular invasion and migration.77 Specifically, the AXL-PYK2 (proline-rich tyrosine kinase 2)-PKCα (protein kinase C alpha) signaling axis has been shown to induce stemness in triple-negative breast cancer (TNBC).