EGFR and cancer: We observed this reproducible ligand-dependent EGFR interaction in several different experimental systems: (1) binding of yeast displayed binders to soluble EGFR-Fc, (2) soluble binders interacting with EGFR-positive human cancer cell lines, (3) response of Jurkat Nur77 reporter CAR T cells and (4) of primary human CAR T cells to EGFR-positive human target cells.