Understanding the distribution of
tumor-associated
antigens on
cancers and normal tissues is essential for selection of targets for
cancer immunotherapy. Seven
carbohydrate antigens, potential targets for
immunotherapy, were studied using a panel of well-characterized MAbs by immunohistochemistry on cryostat-cut tissue sections of 13 types of
cancers and 18 normal tissues. GD2 and GD3 were present on most
cancers of neuroectodermal origin and GD2 was also present on
B cell lymphomas. 9-O-acetyl-GD3 was detected only on
melanoma while
fucosyl GM1 was detected only on small cell
lung cancers (SCLC). Surprisingly, GM2 was strongly expressed on all tested
tumors, including
cancers of neuroectodermal origin and
cancers of epithelial origin.
Polysialic acid was primarily expressed on SCLC and
neuroblastomas.
Globo H was present on most
cancers of epithelial origin. These
antigens were also identified in normal tissues.
Fucosyl GM1 was not expressed significantly on any of the normal tissues analyzed. GD3, GD2, GM2 and
polysialic acid were detected in normal brain to varying degrees. GM2 and
Globo H were expressed on the
luminal surface of epithelia of a variety of organs. The unexpected expression of GM2 on a broad range of
cancers and normal epithelial tissues was confirmed by loss after
methanol fixation and by immune thin layer chromatography.