Neuropilin-1 inhibitors

An ex vivo method of determining the dependency of the invasiveness of a naturally occurring invasive cancer cell on the functionality of neuropilin-1, comprising the steps of:

• b) contacting the cancer cell with a molecule inhibiting neuropilin-1 function;
• c) contacting said cancer cell with a gel-like matrix under conditions suitable for the growth of said cancer cells;
• and
• d) determining the migration of said cancer cells through the gel-like matrix.

An ex vivo method of determining the dependency of the adhesiveness of a naturally occurring invasive cancer cell on the functionality of neuropilin-1, comprising the steps of:

• a) contacting the cancer cell with a molecule inhibiting neuropilin-1 function;
• b) contacting said cancer cell with a layer of extracellular matrix (ECM) proteins under conditions suitable for the growth of said cancer cells;
• and
• c) determining the adhesion of said cancer cells to the layer of ECM proteins.

A method of identifying a ligand binding specifically to the extracellular region of neuropilin-1, wherein said ligand is capable of inhibiting angiogenesis, tube formation of endothelial cells, and/or invasion or adhesion of tumor cells, comprising the steps of:

• a) contacting a phage library of ligands with cancer cells or endothelial cells;
• b) isolating said cells;
• c) removing phages bound unspecifically and/or not bound to said cells;
• d) eluting phages bound to said cells;
• and optionally
• e) determining the identity of the ligand represented by said binding to neuropilin-1
• f) testing the ligand in biochemical or biological assays on it capability to interfere with NP-1 function.