Tumor-associated glycoprotein (TAG-72) in ovarian carcinomas defined by monoclonal antibody B72.3.

Murine IgG1 monoclonal antibody (MoAb) B72.3, reactive with a high molecular weight glycoprotein complex [designated tumor-associated glycoprotein-72 (TAG-72)] was shown, with the use of the avidin-biotin-complex-immunoperoxidase technique and surgically resected tissues, to be reactive with a variety of histologic tumor types. TAG-72 is expressed in at least 5% (and up to 100%) of the malignant epithelial cells in 77% (n = 52) of human primary cancers and 71% (n = 31) of metastatic ovarian cancers of the common "epithelia" histologic category. Of these, several histologic types, including serous and mucinous cystadenocarcinomas, undifferentiated carcinomas, and less common types of ovarian carcinoma, were all shown to express TAG-72. In contrast, normal ovarian tissues and 26 of 27 benign ovarian tumors of various histologic types failed to express similar levels of TAG-72. Of interest is the 1 benign tumor that demonstrated unusual glandular complexity, as well as 3 tumors designated as borderline malignancy, that contained elevated TAG-72 expression. MoAb B72.3 also was used successfully to detect ovarian carcinoma cells in 28 cytologic preparations of human serous effusions and peritoneal washings. The reactivity of MoAb B72.3 was shown to be distinct from that of MoAb OC125 and an anti-CEA MoAb B1.1. The potential applications of MoAb B72.3 in the study of human ovarian cancer cell populations, as well as in several aspects of the management of human ovarian cancer, are discussed.