Synthetic gene encoding human epidermal growth factor 2/neu antigen and uses thereof

Abstract

Synthetic polynucleotides encoding human HER2/neu or a truncated form thereof, are provided, the synthetic polynucleotides being codon-optimized for expression in a human cellular environment. The gene encoding hHER2 is commonly associated with the development of human carcinomas. The present invention provides compositions and methods to elicit or enhance immunity to the protein product expressed by the hHER2 tumor-associated antigen, wherein aberrant hHER2 expression is associated with a carcinoma or its development. This invention specifically provides adenoviral vector and plasmid constructs carrying codon-optimized human HER2 and codon-optimized truncated HER2, and discloses their use in vaccines and pharmaceutical compositions for preventing and treating cancer.

1 . A synthetic nucleic acid molecule comprising a sequence of nucleotides that encodes a human HER2/neu protein as set forth in SEQ ID NO:2, the synthetic nucleic acid molecule being codon-optimized for high level expression in a human cell.  
     
     
         2 . The synthetic nucleic acid molecule of  claim 1  wherein the sequence of nucleotides comprises the sequence of nucleotides set forth in SEQ ID NO:1.  
     
     
         3 . A vector comprising the nucleic acid molecule of  claim 1 .  
     
     
         4 . A host cell comprising the vector of  claim 3 .  
     
     
         5 . A synthetic nucleic acid molecule comprising a sequence of nucleotides that encodes a variant human HER2/neu polypeptide that has at least 90% identity to the amino acid sequence of SEQ ID NO:2, which may include up to Na amino acid alterations over the entire length of SEQ ID NO:2, wherein Na is the maximum number of amino acid alterations, and is calculated by the formula  
           N   a   =X   a −( X   a   Y ),  
       in which X a  is the total number of amino acids in SEQ ID NO:2, and Y has a value of 0.90, wherein any non-integer product of X a  and Y is rounded to the nearest integer prior to subtracting such product from X a , wherein the sequence of nucleotides is codon-optimized for high level expression in a human cell.  
     
     
         6 . A synthetic nucleic acid molecule comprising a sequence of nucleotides that encodes a human HER2ECDTM protein as set forth in SEQ ID NO:14, the synthetic nucleic acid molecule being codon-optimized for high level expression in a human cell.  
     
     
         7 . The synthetic nucleic acid molecule of  claim 6  wherein the sequence of nucleotides comprises the sequence of nucleotides set forth in SEQ ID NO:9.  
     
     
         8 . A vector comprising the nucleic acid molecule of  claim 6 .  
     
     
         9 . A host cell comprising the vector of  claim 8 .  
     
     
         10 . A synthetic nucleic acid molecule comprising a sequence of nucleotides that encodes a variant human HER2ECDTM polypeptide that has at least 90% identity to the amino acid sequence of SEQ ID NO:14, which may include up to N a  amino acid alterations over the entire length of SEQ ID NO:14, wherein N a  is the maximum number of amino acid alterations, and is calculated by the formula  
           N   a   =X   a −( X   a   Y ),  
       in which X a  is the total number of amino acids in SEQ ID NO:14, and Y has a value of 0.90, wherein any non-integer product of X a  and Y is rounded to the nearest integer prior to subtracting such product from X a , wherein the sequence of nucleotides is codon-optimized for high level expression in a human cell.  
     
     
         11 . A process for expressing a human HER2/neu protein in a recombinant host cell, comprising: 
 (a) introducing a vector comprising the nucleic acid of  claim 1  into a suitable host cell; and,    (b) culturing the host cell under conditions which allow expression of said human HER2 protein.    
     
     
         12 . A process for expressing a human HER2ECDTM protein in a recombinant host cell, comprising: 
 (a) introducing a vector comprising the nucleic acid of  claim 6  into a suitable host cell; and,    (b) culturing the host cell under conditions which allow expression of said human HER2ECDTM protein.    
     
     
         13 . A method of preventing or treating HER2-associated cancer comprising administering to a human a vaccine vector comprising a synthetic codon-optimized nucleic acid molecule, the nucleic acid molecule comprising a sequence of nucleotides that encodes a human HER2/neu protein as set forth in SEQ ID NO:2 or a human HER2ECDTM protein as set forth in SEQ ID NO:14.  
     
     
         14 . (canceled)  
     
     
         15 . A method according to  claim 13  wherein the vector is an adenovirus vector or a plasmid vector.  
     
     
         16 . A method according to  claim 15  wherein the vector is an adenoviral vector comprising an adenoviral genome with a deletion in the adenovirus E1 region, and an insert in the adenovirus E1 region, wherein the insert comprises an expression cassette comprising: 
 (a) a codon-optimized polynucleotide encoding a human HER2 protein or a human HER2ECDTM protein; and    (b) a promoter operably linked to the polynucleotide.    
     
     
         17 . A method according to  claim 15  wherein the vector is a plasmid vaccine vector, which comprises a plasmid portion and an expressible cassette comprising: 
 (a) a codon-optimized polynucleotide encoding a human HER2 protein or a human HER2ECDTM protein; and    (b) a promoter operably linked to the polynucleotide.    
     
     
         18 . An adenovirus vaccine vector comprising an adenoviral genome with a deletion in the E1 region, and an insert in the E1 region, wherein the insert comprises an expression cassette comprising: 
 (a) a codon-optimized polynucleotide encoding a human HER2 protein or encoding a human HER2ECDTM protein; and    (b) a promoter operably linked to the polynucleotide.    
     
     
         19 . An adenovirus vector according to  claim 18  which is an Ad 5 vector.  
     
     
         20 . An adenovirus vector according to  claim 18  which is an Ad 6 vector or an Ad 24 vector.  
     
     
         21 . A vaccine plasmid comprising a plasmid portion and an expression cassette portion, the expression cassette portion comprising: 
 (a) a codon-optimized polynucleotide encoding a human HER2 protein or a human HER2ECDTM protein; and    (b) a promoter operably linked to the polynucleotide.    
     
     
         22 . A method of treating a mammal suffering from HER2-associated cancer comprising: 
 (a) introducing into the mammal a first vector comprising: 
 i) a codon-optimized polynucleotide encoding a human HER2 protein or a human HER2ECDTM protein; and  
 ii) a promoter operably linked to the polynucleotide;  
   (b) allowing a predetermined amount of time to pass; and    (c) introducing into the mammal a second vector comprising: 
 i) a codon-optimized polynucleotide encoding a human HER2 protein or a human HER2ECDTM protein; and  
 ii) a promoter operably linked to the polynucleotide.  
   
     
     
         23 . A method according to  claim 22  wherein the first vector is a plasmid and the second vector is an adenovirus vector.  
     
     
         24 . A method according to  claim 22  wherein the first vector is an adenovirus vector and the second vector is a plasmid.