Afterward, a proteolytical cleavage takes place to reveal a cryptic RXXK/R motif located at the C-terminus (CendR motif, C-End Rule), which then binds to neuropilin-1 (NRP-1), activating an endocytic transport pathway responsible for the enhanced transport of anti-cancer drugs into tumors (Figure 3) [80]. Here, NRP1 is linked to cancer.