Ségal-Bendirdjian E, Mannone L, Jacquemin-Sablon A
Unité de Physicochimie et Pharmacologie des Macromolécules Biologiques (CNRS, URA 147), Institut Gustave-Roussy, rue Camille Desmoulins, 94805 Villejuif Cedex, France.
Cell Death Differ. 1998 May;5(5):390-400. doi: 10.1038/sj.cdd.4400357.
The accumulation of molecular genetic defects selected during the adaptation process in the development of cisplatin-resistance was studied using progressive cisplatin-resistant variants (L1210/DDP2, L1210/DDP5, L1210/DDP10) derived from a murine leukemia cell line (L1210/0). Of these cell lines, only the most resistant L1210/DDP10 was cross-resistant to etoposide and deficient in apoptosis induced by these two drugs, indicating that resistance to DNA-damaging agents correlates with a defect in apoptosis. This defect was tightly associated with the loss of a Ca2+/Mg2+-dependent nuclear endonuclease activity present in the less cisplatin-resistant cells. Evidence is presented that p53-dependent function (a) is lost not only in the apoptosis defective L1210/DDP10 cells, but also in the apoptosis susceptible L1210/DDP5 cells; (b) is unrelated to drug-induced cell cycle perturbations. These results suggest that deficiency in the p53 pathway and resistance to DNA-damaging agents due to a defect in apoptosis are independent events.
