[Differentiation of neuroblastoma cells caused by cytochalasin B]

The action of cytochalasin B (CB) on the differentiation of cultured neuroblastoma cells has been studied. CB treatment (1.8 micrograms/ml for 3 days) blocked cytokinesis, leading to the multinucleation of neuroblastoma cells. The replacement of medium with CB by standard medium without CB led to the improvement of cell spreading on the substrate and to the appearance of 43.7 +/- 4.1% of morphologically differentiated cells. 4.7 +/- 0.6% of differentiated cells formed in CB-untreated control cultures. Thus, incubation with CB followed by the agent removal from the medium induced the differentiation of neuroblastoma cells. A possible role of multinucleation in this process is discussed.