Expression of MAM-3 and MAM-6 antigens in endometrial and endocervical adenocarcinomas.

Expression of milkfat globule membrane antigens (MAM-3, MAM-6) was investigated by an indirect immunoperoxidase method on normal and malignant glands of the endocervical and endometrial tissues. MAM-3 antigens, as detectable with monoclonals 67D11 and 115G3, were not detected in normal endometrial glands, but they were found in the majority of endometrial adenocarcinomas. In the endocervix, MAM-3 antigens were present in almost all of the normal glands and in the cancerous glands. MAM-6 antigens, as detectable with monoclonals 115D8 and 115F5, were observed in majority of normal and neoplastic glands within the endometrium and endocervix. The staining appearance of the antigens was generally heterogenous in the neoplastic tissues but more homogenous in normal glandular tissues. These results are discussed and compared with the grade of histological differentiation, mucin production and positivity for CEA.