FAP and breast cancer: Furthermore, the breast cancer cells and the endogeneous FAP-expressing melanoma (MDA-MB435S) show a higher retention of the encapsulated DY676-COOH than the green fluorescent phospholipid used to trace quenched liposomes, which further confirms a rapid binding, cargo release, and recycling of the liposomal components, especially the green phospholipid NBD-DOPE.