Expression of proliferation-associated nuclear antigen in human malignancies

40 specimens consisting of 27 carcinomas, 9 lymphomas, 2 thymomas, 1 sarcoma and 1 neurinoma were studied by immunoperoxidase technique to demonstrate a cell proliferation-associated antigen defined by proliferating cells (PC) antibody. Though PC antibody expression did not seem to correlate well with histologic grading of carcinomas, positivity to this was consistently more intense in carcinomas than in normal epithelia. Correlation with histologic grading of lymphomas was more significant: the high grade types, e.g. ATL, exhibited greater positivity than intermediate grade types, e.g. diffuse medium lymphoma and certainly much more than low grade types, e.g. follicular lymphomas. These data were compared to another proliferation-associated antigen, the transferrin receptor.