MERTK and triple-negative breast carcinoma: To extend observations from EGFR/TAM chimeric receptors, and to validate effects of Axl on motility and invasion on native full-length receptors, we utilized CRISPR/Cas9 technology to specifically knockout Axl in the murine 4 T1 cells (an aggressive triple negative breast cancer cell line that expresses TAMs, Axl being more abundant than Tyro3 and Mertk [53]) (Fig. 2d).