Prostate-specific membrane antigen and uses thereof

Abstract

This invention provides an isolated nucleic acid molecule encoding an alternatively spliced human prostate-specific membrane antigen. This invention provides an isolated nucleic acid comprising a promoter sequence normally associated with the transcription of a gene encoding a human prostate-specific membrane antigen. This invention provides an isolated polypeptide having the biological activity of an alternatively spliced prostate-specific membrane antigen. This invention provides a method of detecting a nucleic acid encoding an alternatively spliced human prostate-specific membrane antigen and a method of detecting a prostate tumor cell in a subject. Lastly, this invention provides a pharmaceutical composition comprising a compound in a therapeutically effective amount and a pharmaceutically acceptable carrier and a method of making prostate cells susceptible to a cytotoxic chemotherapeutic agent.

What is claimed is:  
     
         1 . An isolated nucleic acid encoding an alternatively spliced human prostate-specific membrane antigen.  
     
     
         2 . An isolated DNA of  claim 1 .  
     
     
         3 . An isolated cDNA of  claim 2 .  
     
     
         4 . An isolated RNA of  claim 1 .  
     
     
         5 . An isolated DNA of  claim 2  operatively linked to a promoter of RNA transcription.  
     
     
         6 . A vector which comprises the nucleic acid of  claim 1 .  
     
     
         7 . A host vector system for the production of a polypeptide having the biological activity of the alternatively spliced prostate-specific membrane antigen which comprises the vector of  claim 6  and a suitable host.  
     
     
         8 . A host vector system of  claim 7 , wherein the suitable host is a bacterial cell, insect cell, or mammalian cell.  
     
     
         9 . An isolated nucleic acid comprising a promoter sequence normally associated with the transcription of a gene encoding a human prostate-specific membrane antigen.  
     
     
         10 . An isolated polypeptide having the biological activity of an alternatively spliced prostate-specific membrane antigen.  
     
     
         11 . An antibody which specifically binds to the polypeptide of  claim 10 .  
     
     
         12 . The antibody of  claim 11 , wherein the antibody is monoclonal antibody.  
     
     
         13 . The antibody of  claim 11 , wherein the antibody is polyclonal antibody.  
     
     
         14 . The antibody of  claim 11 , wherein the antibody is labelled with a detectable marker.  
     
     
         15 . The labelled antibody of  claim 14 , wherein the marker is radioactive, or calorimetric, luminescent, or fluorescent marker.  
     
     
         16 . A method of detecting in a sample the presence of a nucleic acid encoding an alternatively spliced human prostate-specific membrane antigen which comprises: a) obtaining a suitable sample; b) extracting RNA from the sample; c) contacting the RNA with reverse transcriptase under suitable conditions to obtain a cDNA; d) contacting the cDNA under hybridizing conditions with two oligonucleotide primers, 
 i) the first primer being capable of specifically hybridizing to a sequence within a DNA sequence encoding prostate specific membrane antigen located immediately 3′ of nucleotide 114 of such DNA sequence, with the proviso that the 3′ end of the primer does not hybridize to any sequence located 5′ of nucleotide 114, and    ii) the second primer being capable of specifically hybridizing to a sequence within a DNA sequence encoding prostate specific membrane antigen located immediately 5′ of nucleotide 381 of such DNA sequence, with the proviso that the 5′ end of the primer does not hybridize to any sequence located 3′ of nucleotide 381;    d) amplifying any cDNA to which the primers hybridize to so as to obtain amplification product; e) determining the size of the amplification product; f) comparing the size of the amplification product to the size of the amplification product known to be obtained using the same primers with a non alternatively spliced human prostate specific membrane antigen, wherein a smaller amplification product is indicative of the presence of the alternatively spliced prostate specific membrane antigen, so as to thereby detect the presence of the alternatively spliced human prostate-specific membrane antigen in the sample.    
     
     
         17 . A method of detecting a prostate tumor cell in a subject which comprises: which comprises: a) obtaining a suitable sample; b) extracting RNA from the sample; c) contacting the RNA with reverse transcriptase under suitable conditions to obtain a cDNA; d) contacting the cDNA under hybridizing conditions with two oligonucleotide primers, 
 i) the first primer being capable of specifically hybridizing to a sequence within a DNA sequence encoding prostate specific membrane antigen located immediately 3′ of nucleotide 114 of such DNA sequence, with the proviso that the 3′ end of the primer does not hybridize to any sequence located 5′ of nucleotide-114, and    ii) the second primer being capable of specifically hybridizing to a sequence within a DNA sequence encoding prostate specific membrane antigen located immediately 5′ of nucleotide 381 of such DNA sequence, with the proviso that the 5′ end of the primer does not hybridize to any sequence located 3′ of nucleotide 381;    d) amplifying any cDNA to which the primers hybridize to so as to obtain amplification product; e) determining the amount of the amplification product; f) comparing the amount of the amplification product to the amount of the amplification product known to be obtained using the same primers with a non alternatively spliced human prostate specific membrane antigen, wherein a greater amount of the prostate specific membrane antigen is indicative of a prostate tumor cell in the subject, so as to thereby detect prostate tumor cell in the subject.    
     
     
         18 . A compound comprising a conjugate of a cytotoxic agent and one or more amino acid residues, wherein each amino acid residue is glutamate or aspartate.  
     
     
         19 . The compound of  claim 18 , wherein the compound has the structure:  
       
         
           
           
               
               
           
         
         wherein n is an integer from 1-10 inclusive.  
       
     
     
         20 . The compound of  claim 18 , wherein the compound has the structure:  
       
         
           
           
               
               
           
         
         wherein n is an integer from 1-10 inclusive.  
       
     
     
         21 . The compound of  claim 18 , wherein the compound has the structure:  
       
         
           
           
               
               
           
         
         wherein n is an integer from 1-10 inclusive.  
       
     
     
         22 . A pharmaceutical composition comprising the compound of any of claims  18 - 21  in a therapeutically effective amount and a pharmaceutically acceptable carrier.  
     
     
         23 . A method of making prostate cells suseptible to a cytotoxic chemotherapeutic agent, which comprises contacting the prostate cells with an the compound of any claims  18 - 21  in an amount effective to render the prostate cells suseptible to the cytotoxic chemotherapeutic agent.