Psca: prostate stem cell antigen and uses thereof

Abstract

The invention provides a novel prostate cell-surface antigen, designated Prostate Stem Cell Antigen (PSCA), which is widely over-expressed across all stages of prostate cancer, including high grade prostatic intraepithelial neoplasia (PIN), androgen-dependent and androgen-independent prostate tumors.

What is claimed is: 
     
         1 . An immunotherapy method comprising administering to a subject having a disease associated with the expression of Prostate Stem Cell Antigen (PSCA) a therapeutically effective amount of an antibody, wherein the antibody is a monoclonal antibody designated 1G8 (American Tissue Type Culture Collection (ATCC) No. HB-12612) or a fragment thereof, a humanized form of the 1G8 monoclonal antibody, an immunoconjugate comprising the 1G8 monoclonal antibody, or a fusion protein comprising the fragment of the 1G8 monoclonal antibody. 
     
     
         2 . The method of  claim 1 , wherein the disease is associated with the overexpression of PSCA. 
     
     
         3 . The method of  claim 1 , wherein the disease is a cancer. 
     
     
         4 . The method of  claim 3 , wherein the cancer is bladder cancer, prostate cancer, metastasis of prostate cancer, or pancreatic cancer. 
     
     
         5 . The method of  claim 1 , wherein the antibody is a 1G8 monoclonal antibody deposited as ATCC No. HB-12612. 
     
     
         6 . The method of  claim 1 , wherein the fragment comprises a Fab, F(ab′) 2 , or Fv. 
     
     
         7 . The method of  claim 1 , wherein the antibody is a humanized form of the 1G8 monoclonal antibody. 
     
     
         8 . The method of  claim 1 , wherein the antibody is an immunoconjugate comprising the 1G8 monoclonal antibody linked to a therapeutic agent. 
     
     
         9 . The method of  claim 8 , wherein the therapeutic agent is an anti-tumor drug, a cytotoxic agent, a radioactive agent, a cytokine, a second antibody, or an enzyme. 
     
     
         10 . The method of  claim 9 , wherein the therapeutic agent is a cytotoxic agent. 
     
     
         11 . The method of  claim 9 , wherein the therapeutic agent is a radioactive isotope. 
     
     
         12 . The method of  claim 1 , wherein the antibody is a fusion protein comprising the fragment of the 1G8 monoclonal antibody. 
     
     
         13 . The method of  claim 1 , wherein the method further comprises administering a chemotherapeutic drug to the subject. 
     
     
         14 . The method of  claim 1 , wherein the method further comprises administering radiation therapy to the subject.