DMSO INDUCES DIFFERENTIATION OF MURINE ARS ASCITIC RETICULUM SARCOMA CELLS / 解剖学报

ABSTRACT

Murine ARS reticulum sarcoma cells, when incubated with 1.5, 2.0 and 2.5% DMSO in vitro, were induced to differentiate into macrophage like cells. They showed reduction of cellular and nuclear size and lowering of nucleo-cytoplasmic ratio with marked change in nuclear size. The most effective one was 2.5% DMSO which caused marked reduction of nucleolar size. Tumor cells with nucleo-cytoplasmic ratio less than 0.5 and with reduced nucleoli resembled macrophage. 2.5% DMSO induced the increase of non-specific esterase positive cells and the increase of polystyrene phagocytic percentage and phagocytic index. Under EM, 2.5% DMSO treated ARS cells with nucleocytoplasmic ratio less than 0.5 exhibited abundant cytoplasmic organelles, developed Golgi complex and secondary lysosomes. Scanning EM showed that many large cells with numerous dense slender microvilli were observed in the control. Under the action of 2.5% DMSO, large cells were reduced, small cells were increased and microvilli markedly decreased and shortened. These small cells appeared to be differentiated macrophage like cells and were similar to small cells seen under EM and light microscope. In 2.5% DMSO treated groups, the mitotic index of ARS cells were markedly lowered.