FAP and liver cancer: In hFAP-HT1080-derived and liver cancer patient-derived xenograft models, it was concluded that hFAP-CAR T cells inhibited tumor progress by eliminating human FAP-positive tumor cells or stroma cells, in line with other reports showing that FAP-redirected T cells can inhibit tumor growth by depleting FAP+ stromal cells or tumor cells (7, 27–29).