Constitutive and antibody-induced internalization of prostate-specific membrane antigen Academic Article uri icon


MeSH Major

  • Antigens, Surface
  • Carcinoma
  • Prostate-Specific Antigen
  • Prostatic Neoplasms


  • Prostate-specific membrane antigen (PSMA) is a cell surface glycoprotein expressed predominantly by prostate cancer cells. We have characterized four monoclonal antibodies that bind to the extracellular domain of PSMA (Liu et al., Cancer Res., 57: 3629-3634, 1997). Here we report that viable LNCaP cells internalize these antibodies. Laser scanning confocal microscopy reveals that the internalized antibodies accumulate in endosomes, and immunoelectron microscopy reveals that endocytosis of the PSMA-antibody complex occurs via clathrin-coated pits. In addition, a quantitative cell surface biotinylation assay demonstrates that PSMA is constitutively endocytosed in LNCaP cells and that anti-PSMA antibodies increase the rate of internalization of PSMA. These studies suggest that PSMA might function as a receptor mediating the internalization of a putative ligand. The availability of prostate-specific internalizing antibodies should aid the development of novel therapeutic methods to target the delivery of toxins, drugs, or short-range isotopes specifically to the interior of prostate cancer cells.

publication date

  • September 15, 1998



  • Academic Article



  • eng

PubMed ID

  • 9751609

Additional Document Info

start page

  • 4055

end page

  • 60


  • 58


  • 18