Comparative Studies of Steroidogenesis Inhibitors (Econazole, Ketoconazole) on Human Breast Cancer MCF-7 Cell Proliferation by Growth Experiments, Thymidine Incorporation and Flow Cytometric DNA Analysis

Abstract

The effects of aminoglutethimide, econazole and ketoconazole on human breast cancer cells in culture were compared with those of tamoxifen using four methods (growth experiments, thymidine incorporation, monoparameter and bivariate DNA content flow cytometry analysis). Aminoglutethimide (1 nM-10 microM) had no effect on cell proliferation after 8 days of treatment and did not decrease thymidine tritiated incorporation during logarithmic phase. Even at 20 microM, similar results were obtained with flow cytometry. Econazole and ketoconazole (1 nM-1 microM) decreased MCF-7 cell proliferation in a time- and dose-dependent fashion. They also decreased tritiated thymidine incorporation. By using flow cytometry and a monoclonal antibody against bromodeoxyuridine, we showed an accumulation of MCF-7 cells treated by imidazoles derivatives in G0-G1 phase of the cell cycle.