The LeYdeterminant, A difucosylated type 2 blood group-related antigen, is A positional isomer of the Lebblood group antigen and A fucosylated derivative of the Lex antigen. The Lex antigen behaves like an oncodevelopmental tumor-associated antigen in human colon cancer, and extended polyfucosyl Lex antigens are more specific for colon cancer tissues than are simple, monofucosyl Lexantigens. The present investigation compared the expression of simple and extended LeYantigens in A variety of malignant and nonmalignant human colonic tissues to gain insight into the normal distribution and cancer-associated expression of these antigens. Monoclonal antibody AH-6, which recognizes the LeYepitope irrespective of its carrier carbohydrate chain, stained the majority of specimens regardless of malignant potential or location within the colon. In contrast, CC-1 and CC-2 monoclonal antibodies, which recognize extended LeYstructures, and KH-1, which is specific to trifucosyl LeY, preferentially stained malignant colonic tissues and rarely stained normal colonic mucosae. Mucosa immediately adjacent to cancer usually stained with AH-6 but not with KH-1, CC-1, or CC-2. Extended or trifucosyl LeYantigen expression was limited exclusively to premalignant (adenomatous) polyps and was invariably absent from nonpremalignant (hyperplastic) polyps. Moreover, among adenomatous polyps, extended LeYantigen expression tended to correlate with three parameters of malignant potential: larger polyp size; villous histology, and severe dysplasia. AH-6 failed to distinguish between hyperplastic and adenomatous polyps. In second-trimester fetal colonic mucosa, AH-6 bound to both proximal and distal segments whereas KH-1, CC-1, and CC-2 bound only to proximal segments. We conclude that in human colon, the LeYhapten is an oncodevelopmental cancer-associated antigen and extended LeYantigens are highly specific markers for malignancy and premalignancy. copyright.
|Number of pages||8|
|State||Published - 1 Nov 1986|