Nuclear changes in Friend erythroleukemia cells treated with arabinosylcytosine in vitro.

Friend erythroleukemia cells (strain 745 A 19) grown in DME medium were treated with arabinosylcytosine (Ara-C) for 12 hours. After treatment, the cells were partly fixed and prepared for electron and light microscopy. This treatment produced a substantial increase in the number of malignancy-associated changes (MAC) present in untreated cells, of the nuclear "holes" and of the mean nuclear masses/cell ratio. At the same time, decrease in the growth rate was evident. Treatment with this antiblastic drug seems to be suitable for inducing deeper morphological changes related to neoplasia in transformed cells.