The identification of proliferation and tumour-induced proteins in human endothelial cells: a possible target for tumour therapy.

The continued growth and spread of tumours is dependent on the proliferation of the endothelial cells of their vasculature. The presence of proliferation- or tumour-induced surface proteins on these endothelial cells would offer a suitable epitope for monoclonal antibody therapy of tumours. Using cultured human umbilical and capillary endothelial cells, we have stimulated them with simple mitogens and tumour conditioned media and examined the proteins induced by [35S]methionine incorporation and 125I-surface-labelling. Two-dimensional polyacrylamide gel electrophoresis revealed the induction of proliferation and tumour-related antigens on the surface of the endothelial cells. Subsequent monoclonal antibody studies suggest that tumour specific surface proteins are present on most tumour endothelium.