Abstract

Interactive laser cytometry was applied to measure intracellular fluorescence of doxorubicin (DOX) accumulation in a uterine sarcoma cell line, MES-SA and a series of multidrug resistant sublines, Dx0.3, Dx1 and Dx5. Exposure of each cell line to 10 mu M DOX for 2 h resulted in an intracellular fluorescent level directly correlated to its sensitivity to the drug but inversely related to its cellular P-glycoprotein (P-gp) level. The morpholinyl anthracyclines, methoxymorpholinyl DOX (MMDX) and morpholinyl DOX (MRA), were equally highly cytotoxic against the multidrug sensitive and resistant cancer cells. After exposure to 10 mu M of MMDX or MRA for 2 h, the multidrug resistant cells, Dx5, retained as much intracellular fluorescence as the multidrug sensitive cells, MES-SA. In the resistant cells, the intracellular fluorescence of MMDX or MRA was 8 fold higher than that of DOX. Interactive laser. cytometer is a useful fool for screening cancer cells with the MDR phenotype and for identifying new anthracyclines effective against drug resistant malignancies.

View details for Web of Science ID A1994PT93300012

View details for PubMedID 21559709