Robo1-Fc fusion protein and use thereof for treating tumours
The present invention relates to a Robo1-Fc recombinant protein and to the use thereof for treating diseases in which a Slit protein is overexpressed, in particular cancer. The invention also relates to a composition including such a recombinant protein. Another aspect of the invention involves using a Robo1-Fc molecule as a diagnostic tool for detecting the overexpression of a molecule belonging to the Slit family in a patient.
1. A homogeneous composition of Robo-Fc recombinant protein comprising the extracellular region of a Robo1 protein, a linker and an immunoglobulin Fc domain,
wherein said extracellular region of the Robo1 protein consists of the Ig1 and Ig2 immunoglobulin domains corresponding to amino acids 22-220 of SEQ ID NO: 2,
wherein the immunoglobulin Fc domain is from human immunoglobulin G4 and comprises S241P and L248E mutations (Kabat numbering), and wherein the lysine located in the C-terminal position is absent.
2. The homogeneous composition of Robo-Fc recombinant protein according to claim 1 , wherein the sequence has at least 80% identity with the sequence of SEQ ID NO: 4, SEQ ID NO: 6 or SEQ ID NO: 24.
3. A pharmaceutical composition comprising the homogeneous composition of Robo-Fc recombinant protein of claim 1 .
4. A method for treating a cancer associated with overexpression of a protein of the Slit family comprising administering to a subject in need thereof the pharmaceutical composition of claim 3 .
5. The method of claim 4 , wherein the cancer is lung cancer or lung metastases.
6. The pharmaceutical composition according to claim 3 further comprising at least one excipient.
7. A method for detecting overexpression of a molecule of the Slit family in a patient comprising contacting a biological sample from the patient with the homogeneous composition of Robo-Fc recombinant protein of claim 1 .
8. The homogeneous composition of Robo-Fc recombinant protein according to claim 1 , which is produced by transfection of expression plasmid encoding a protein having the amino acid sequence of SEQ ID NO: 4, SEQ ID NO: 6 or SEQ ID NO: 24 into CHO cell, recovery in culture supernatant and purification.
9. The homogeneous composition of Robo-Fc recombinant protein according to claim 1 , wherein the Robo-Fc recombinant protein consists of amino acids 22 to 454 of SEQ ID NO: 4.
10. The homogeneous composition of Robo-Fc recombinant protein according to claim 1 , wherein the Robo-Fc recombinant protein consists of amino acids 22 to 453 of SEQ ID NO: 6.
11. The homogeneous composition of Robo-Fc recombinant protein according to claim 1 , wherein the Robo-Fc recombinant protein consists of amino acids 21 to 453 of SEQ ID NO: 24.