FAP and neoplasm: Thus, we envisioned that the bispecific FAP and endoglin targeting liposomes (termed Bi-FAP/mEnd-IL, and abbreviated Bis-IL in the Figures) should be able to accumulate in the tumors based on distinct specificities to the murine FAP-expressing tumor associated fibroblasts, murine endoglin-expressing tumor vascular endothelial cells, and for tumor models that express the human FAP protein, also the tumor cells.