Aminopeptidase A (ENPEP)

The gp160 antigen is a differentiation-related kidney glycoprotein of 160 kD that is expressed on the surface of epithelial cells of the glomerulus and proximal tubule cells of the human nephron. Despite the fact that almost all renal cell carcinomas derive from proximal tubule cells, about 20% of them lack gp160 expression. Nanus et al. (1990) showed that expression of gp160 by cultured renal cell carcinomas correlated with the resistance of RCC cells to the antiproliferative effects of alpha-interferon, while lack of expression correlated with the sensitivity to alpha-interferon. Nanus et al. (1993) purified the gp160 protein, obtained partial sequences of random peptides, and isolated a full-length cDNA. The human cDNA shares 78% homology with the murine B-lymphocyte differentiation protein that exhibits aminopeptidase A activity.