[The Effects of Cyclosporin A on Leukemia Cells In Vitro]

To explore the mechanism of CSA in the reversal of drug-resistance of leukemia cells, K562 and K562/ADM cells were used for in vitro study. Drug sensitivity of cells was evaluated by MTT assay and cell survival by trypan blue exclusion. Apoptosis was detected by terminal-deoxynucleotidyl transferase mediated d-UTP nick end labeling (TUNEL) and agarose gel electrophoresis. The results showed that 1.0 mg/L CSA alone have no effect on the survival of K562 and K562/ADM cell lines, but it could enhance the chemotherapy sensitivity of the 2 cell lines, and accelerate the apoptosis induced by ADM. These effects were stronger in K562/ADM cell line, when the concentration of CSA > 1.0 mg/L, CSA itself could kill leukemia cells and induce the apoptosis of the 2 cell lines. It is concluded that CSA can reverse leukemia cells' drug-resistance by enhance apoptosis of the leukemic cells, CSA itself can induce leukemia cells' apoptosis and kill leukemia cell too.