Therapeutic multi-targeting constructs and uses thereof

Abstract

The present invention provides constructs comprising a plurality of peptides capable of targeting at least two different extracellular tumor antigens and a toxin, optionally connected to an organic scaffold. Use of such constructs in treating cancer are provided as well. The invention also provides particular peptides binding certain extracellular tumor antigens as well as toxins having antitumor activity.

1 . A peptide selected from the group consisting of:
 (i) a peptide binding specifically to an extracellular tumor antigen selected from human Epidermal Growth Factor Receptor (EGFR) and human Programmed death-ligand 1 (PD-L1), wherein the peptide comprises an amino acid sequence selected from SEQ ID NO: 1 and SEQ ID NO: 2;   (ii) a peptide binding specifically to human eukaryotic Elongation Factor 2 (eEF2), wherein the peptide comprises an amino acid sequence selected from SEQ ID NO:3 and SEQ ID NO: 4; and   (iii) a cyclic form of the peptide of (i) or (ii).   
     
     
         2 . An analog of the peptide of  claim 1 , having a sequence identity of at least 90% to the peptide. 
     
     
         3 . A conjugate comprising at least one peptide of claim  1 (i). 
     
     
         4 . The conjugate of  claim 3 , wherein the conjugate comprises an amino acid sequence selected from SEQ ID NO: 1 and SEQ ID NO: 2 and a peptide comprising an amino acid sequence selected from SEQ ID NO: 3 and SEQ ID NO: 4. 
     
     
         5 . A construct comprising multiple copies of the peptides of claim  1 (i) and multiple copies of a toxin, wherein the multiple copies of the peptides and the toxin are covalently bound through an organic scaffold comprising a polyethylene glycol (PEG) molecule or a modified PEG molecule comprising a plurality of sites. 
     
     
         6 . A pharmaceutical composition comprising the peptide of  claim 1 , a conjugate thereof, or a construct comprising the peptide, and a pharmaceutically acceptable carrier. 
     
     
         7 . A method of treating cancer in a subject in need thereof comprising administering a therapeutically effective amount of a peptide of  claim 1  or of a conjugate or construct comprising the peptide. 
     
     
         8 . A method of inducing cell death comprising contacting cells with a composition comprising at least one peptide according to  claim 1  or of a conjugate thereof. 
     
     
         9 . An isolated polynucleotide or a nucleic acid construct thereof, comprising a sequence encoding a peptide according to  claim 1 . 
     
     
         10 . A construct comprising at least two different peptides binding to at least two different extracellular tumor antigens, and multiple copies of at least one toxin, wherein the two different peptides are selected from peptides that bind specifically to a tumor antigen selected from EGFR, PD-L1, HGFR (cMET) and HER2, wherein the peptides and the toxin are covalently bound through an organic scaffold, and wherein each one of the peptides consists of up to 50 amino acids. 
     
     
         11 . The construct of  claim 10 , wherein the construct comprises (i) a plurality of peptides that binds specifically to EGFR and a plurality of peptides that binds specifically to PD-L1; (i) a plurality of peptides that binds specifically to EGFR and a plurality of peptides that binds specifically to HGFR (cMET); or (iii) a plurality of peptides that binds specifically to PD-L1 and a plurality of peptides that binds specifically to HGFR (cMET). 
     
     
         12 . The construct of  claim 10 , wherein the peptide that binds specifically to EGFR is a peptide comprising the amino acid sequence SEQ ID NO: 1, and the peptide that binds specifically to PD-L1 is a peptide comprising the amino acid sequence SEQ ID NO: 2. 
     
     
         13 . The construct of  claim 10 , wherein the construct is characterized by at least one of:
 (i) the construct comprises from 3 to 10 different peptides or from 2 to 10 different toxins;   (ii) the at least one toxin is a peptide, polypeptide or protein selected from the group consisting of a toxin specifically binding to a eukaryotic elongation factor 2, BIM-BH3 of SEQ ID NO: 5, Diphtheria toxin,  Pseudomonas  exotoxin, Anthrax toxin, botulinum toxin, Ricin, PAP, Saporin, Gelonin, Momordin, ProTx-I ProTx-II,  Conus californicus  toxin, snake-venom toxin, and cyanotoxin;   (iii) the at least one toxin comprises an amino acid sequence selected from SEQ ID NOs: 3, 4 and 5;   (iv) the organic scaffold comprises a polyethylene glycol (PEG) molecule or a modified PEG molecule comprising a plurality of sites available to bind the peptides and the toxin(s)   (v) each one of the peptides and the toxins is bound to the scaffold.   
     
     
         14 . The construct of  claim 10 , wherein construct comprises a plurality of peptides that bind specifically to EGFR, a plurality of peptides that binds specifically to PD-L1 and a plurality of peptides that binds specifically to HGFR (cMET). 
     
     
         15 . The construct of  claim 10 , wherein construct comprises multiple copies of a toxin comprising the amino acid sequence SEQ ID NOs: 3 and multiple copies of a toxin comprising the amino acid sequence SEQ ID NOs: 4. 
     
     
         16 . A pharmaceutical composition comprising a construct according to  claim 10 , and a pharmaceutically acceptable excipient. 
     
     
         17 . A method of treating cancer in a subject in need thereof comprising administering to said subject therapeutical amount of the construct according to  claim 10 .