PRESENCE OF THE LONG-CHAIN FORM OF POLYSIALIC ACID OF THE NEURAL CELL-ADHESION MOLECULE IN WILMS TUMOR - IDENTIFICATION OF A CELL-ADHESION MOLECULE AS AN ONCODEVELOPMENTAL ANTIGEN AND IMPLICATIONS FOR TUMOR HISTOGENESIS

  • 1 November 1988
    • journal article
    • research article
    • Vol. 133  (2) , 227-240
Abstract
The long chain form of polysialic acid characteristic of the low adhesive embryonic form of the neural cell adhesion molecule NCAM is temporally and spatially expressed in developing kidney but undetectable in normal adult kidney. Therefore, this molecule represents a developmentally regulated antigen in kidney contrasted with neural tissue, where it is also detectable in the adult brain. This investigation of 25 Wilms'' tumors comprising all different histologic types demonstrates expression of this molecule under conditions of malignant growth. Immunostaining was observed in Wilms'' tumors with both a monoclonal anti-polysialic acid antibody and a polyclonalanti-NCAM polypeptide antiserum. Intense cell surface staining sensitive to endosialidases specificially hydrolyzing .alpha.2,8 linked (poly)sialic acid was detectable in blastermal regions, and weaker, variable labeling was seen over tubules and glomeruloid blodes. The stroma was not stained. This is evidence indicating that Wilms'' tumor originates from the embryonic equivalent of induced metanephrogenic mesenchyma. It seems unlikely however, that the stroma is derived from the blastema. The same high molecular mass broad band typical of the embryonic form of NCAM was revealed by immunoblot analysis of homogenates from Wilms'' tumor as well as from emmbryonic kidney and brain. In situ hybridization demonstrated the presence of mRNA for NCAM in all but stromal elements of Wilms'' tumors. Thus polysialic acid is present on NCAM and represents a new oncodevelopmental antigen in human kidney. Polysialic acid was greatly reduced or absent by immunohistochemisty and immunoblotting in necrotic tumor areas.

This publication has 72 references indexed in Scilit: