Abstract
DNA distributions were recorded flow cytometrically (FCM) in human normal, precancerous (P1 characterized by ductal hyperplasia and/or lobular hyperplasia, and P2 characterized by carcinomata lobularia in situ and intraductal carcinoma) and malignant breast tissues. Heparin, a polyanion, mediated two changes: (a) a time-dependent increase in fluorescence intensity (IFI) considered to be inversely proportional to the proliferative activity. IFI was significantly lower in carcinomas than in P2, in normal and in P1 tissues; it identified a highly and a poorly heparin-sensitive subgroup of carcinomas, which differed in respect to histological type and tumor stage distribution; (b) a time-dependent increase in the percentage of recorded DNA aneuploid cells (IAC) at the expense of DNA diploid cells in mixed cell population. IAC is considered to correspond to cell membrane permeability. DNA aneuploid cell populations homogeneous in respect to DNA – index (DI) seem to be heterogeneous in respect to cell membrane function. Duct carcinomas showed significantly higher IAC than lobular carcinomas.