Neurite outgrowth and cell cycle kinetic changes induced by cis-diamminedichloroplatinum II and retinoic acid in a human neuroblastoma cell line.

The aim of this study was to analyze by flow cytometry the effect of cis-diamminedichloroplatinum II (CDDP) and retinoic acid (RA) on the cell cycle of a neuroblastoma cell line (SK-N-BE (2)C NB) and to correlate the kinetic data with cell morphology. CDDP at 1 microgram/ml induced a dramatic G2 + M cell cycle phases block (nearly 200% increase with respect to control) 2 days after treatment. The G2 + M block was spontaneously reversed starting from the 4th day. The cells treated with 10 microM RA were, instead, induced to irreversibly enter the G0 + G1 phase of the cell cycle (nearly 20% increase with respect to control) 48 h after treatment. Neurite-like structures were observed for both CDDP and RA treated cells. These data suggest different cell cycle dependent molecular mechanisms and different degrees of differentiation during CDDP or RA treatment of NB cells.