Nucleic acid and corresponding protein entitled 98P4B6 useful in treatment and detection of cancer

Abstract

A novel gene 098P4B6 (also designated STEAP-2) and its encoded protein, and variants thereof, are described wherein 98P4B6 exhibits tissue specific expression in normal adult tissue, and is aberrantly expressed in the cancers listed in Table I. Consequently, 98P4B6 provides a diagnostic, prognostic, prophylactic and/or therapeutic target for cancer. The 98P4B6 gene or fragment thereof, or its encoded protein, or variants thereof, or a fragment thereof, can be used to elicit a humoral or cellular immune response; antibodies or T cells reactive with 98P4B6 can be used in active or passive immunization.

1 . A STEAP-2 small interfering RNA (siRNA) comprising a nucleic acid sequence that is complementary to 19, 20, 21, 22, 23, 24, or 25 contiguous nucleotides of SEQ ID NO: 2, wherein said siRNA is effective to inhibit translation of a protein encoded by SEQ ID NO: 3.  
     
     
         2 . The STEAP-2 siRNA of  claim 1 , wherein the nucleic acid sequence is 21 contiguous nucleotides of SEQ ID NO: 2.  
     
     
         3 . The STEAP-2 siRNA of  claim 1 , wherein the nucleic acid sequence is 21 contiguous nucleotides of SEQ ID NO: 2.  
     
     
         4 . The STEAP-2 siRNA of  claim 1 , further comprising an excipient.  
     
     
         5 . A method for identifying a candidate ribonucleic acid that inhibits STEAP-2 expression, comprising: 
 introducing the candidate ribonucleic acid to a cell that expresses STEAP-2 (SEQ ID NO: 2); and    identifying the candidate ribonucleic acid that inhibits STEAP-2 expression.    
     
     
         6 . The method of  claim 5 , wherein the system is in vivo.  
     
     
         7 . The method of  claim 5 , wherein the system is in vitro.  
     
     
         8 . The method of  claim 5 , wherein the ribonucleic acid comprises a STEAP-2 small interfering RNA (siRNA) corresponding to 19, 20, 21, 22, 23, 24, or 25 contiguous nucleotides in length of SEQ ID NO: 2.  
     
     
         9 . The method of  claim 5 , wherein the molecule is an antisense polynucleotide.  
     
     
         10 . The method of  claim 5 , wherein the molecule is a ribosome.  
     
     
         11 . The method of  claim 5 , wherein the candidate ribonucleic acid is identified by quantifying a decrease in STEAP-2 cell proliferation.  
     
     
         12 . A method of inhibiting STEAP-2 expression, comprising: 
 providing to a cell expressing STEAP-2 (SEQ ID NO: 2) a ribonucleic acid that inhibits STEAP-2 expression.    
     
     
         13 . The method of  claim 12 , wherein the ribonucleic acid comprises a STEAP-2 small interfering RNA (siRNA) corresponding to 19, 20, 21, 22, 23, 24, or 25 contiguous nucleotides in length of SEQ ID NO: 2.  
     
     
         14 . The method of  claim 12 , wherein the molecule is an antisense polynucleotide.  
     
     
         15 . The method of  claim 12 , wherein the molecule is a ribosome.  
     
     
         16 . The method of  claim 12 , wherein the ribonucleic acid inhibits transcription.  
     
     
         17 . The method of  claim 12 , wherein the ribonucleic acid inhibits translation.  
     
     
         18 . The method of  claim 12 , wherein the cell is a cancer cell.  
     
     
         19 . The method of  claim 18 , wherein the cancer cell is derived from a tissue set forth in Table I.  
     
     
         20 . The method of  claim 12 , wherein inhibition of STEAP-2 expression results in a decrease in cell proliferation.