The cytokinetic effects of ADR on a human lymphoma cell line were tested, using sequential DNA histograms rapidly provided by pulse cytophotometry. ADR induced a block of the cell cycle progression in G2 phase, the extent of which was concentration and time dependent. After 48 hr incubation with 0.05 and 0.1 μg/ml the accumulation of G2 cells increased steadily to a maximum of 3 to 4 fold over controls. Shorter exposure times (1-12 hr) induced a partially reversible block. In addition there was a time and concentration dependent reversible block in G1. 0.25 and 0.5 μg/ml reversibly blocked the G1/S transition, resulting in a smaller initial G2 accumulation. The lethal effects of ADR have been shown cell cycle independent for this cell line. The high degree of G2 accumulation resulting after short exposure times indicate that the blocking effect of ADR is also exerted throughout the cell cycle. This effect is delayed, irreversibly manifested only in G2 and likely related to cell killing. The authors suggest that the G2 arrest may provide a rapid clinical predictive test for response to ADR.
|Pages (from-to)||No. 90|
|Journal||Proceedings of the American Association for Cancer Research|
|State||Published - 1975|