FAP and cancer: We evaluated whether targeting CAFs with fibroblast activation protein alpha (FAP)-coated, 8-<i>O</i>-methylfusarubin-loaded nanoparticles called anti-FAP@OMF-NPs could enhance the anti-tumor efficacy of folate receptor alpha (FRα)-specific CAR-T cells against TNBC in a 3D cancer cells-CAFs co-culture heterospheriod (HS) model.