Journal of Dental Research, Vol 59, 2014-2020, Copyright © 1980 by International & American Associations for Dental Research Online Journals
The expression of the epithelial blood-group substances: normal and malignant tissues
D. I. George, C. T. Hanks and D. E. Lopatin
The blood-group isoantigens are macromolecules localized to the plasma
membranes of certain epithelial tissues. These substances are not
detectable on the epithelium once it has undergone malignant
transformation. Results of this investigation have demonstrated that the
loss of detectability of the blood-group isoantigens does not appear to be
related to a "masking" effect by an increase in surface sialic acid. Using
fluorescein-labeled lectins specific for sugar subunits which are
components of the blood-group oligosaccharide chain, it was found that the
malignant cells and cells of the parabasal layer of normal oral epithelium
had high levels of N-acetyl-D-glucosamine (GlcNAC), the subterminal sugar
residue of the blood-group chain. The basal cells of normal epithelium and
a minority of the malignant cells demonstrated levels of
D-galactose-N-acetyl-D-galactosamine, which are the most proximal
blood-group sugar subunits, as well as subunits of other membrane antigens.
Our results indicate that malignant cells seem to be capable of
synthesizing the blood-group oligosaccharide chains to the same level as
the normal cells of the parabasal layer of stratified squamous epithelium.
This level is just subjacent to the terminal D-galactose residue of the
blood-group precursor chain. Increased or decreased differentiation
characteristics of squamous cell carcinomas did not alter the level of
blood-group synthesis. However, there may be a correlation between the
level of synthesis of these antigens and the ability of the cells to
demonstrate motility and to proliferate.
