Engineering of CAR-NK cells targeting fibroblast activation protein (FAP), a serine protease overexpressed by CAFs (Figure 1C), has been shown to inhibit tumor progression in non-small cell lung cancer models [104] and cervical cancer models, where anti-FAP CAR-NK-92 cells demonstrated an 1.5-fold increase in CD107a expression and reduced CAF spheroid fluorescence by 50–83% within 34–72 h compared to controls (p < 0.05) [105]. Here, FAP is linked to neoplasm.