摘要
To study the resistant mechanisms of cisplatin in human lung adenocarcinoma cell line A 549 DDP. A 549 DDP cells was established by stepwise increasing concentration of cisplatin (CDDP) in medium. Interstrand cross linked DNA (ICL) was measured by ethidium bromide fluorescence assay. The intracellular and intranuclear accumulation of cisplatin was measured by atomic absorption spectrometry. The removal of GS X was determined by FCM and fluorescence microscopy. Results: The A 549 DDP cell line was 8.9 fold resistance relative to the parental A 549 cell line. The formation of ICL in A 549 was 6.28 times higher than that in A 549 DDP cells. The intracellular and intranuclear accumulation of cisplatin in A 549 cells was 5.9 times and 4.1 times higher than that in A 549 DDP cells, respectively. The ability of GS X pump pumped GS X complex (GS Pt) in A 549 DDP cells was higher than that in A 549 . The repair rate in A 549 DDP cells was 2 times higher than that in A 549 . Conclusions: Decreased accumulation and increased export of cisplatin might be the main mechanism of cisplatin resistant A 549 DDP cells while the enhanced repair capacity of DNA may play a role in CDDP resistance.
To study the resistant mechanisms of cisplatin in human lung adenocarcinoma cell line A 549 DDP. A 549 DDP cells was established by stepwise increasing concentration of cisplatin (CDDP) in medium. Interstrand cross linked DNA (ICL) was measured by ethidium bromide fluorescence assay. The intracellular and intranuclear accumulation of cisplatin was measured by atomic absorption spectrometry. The removal of GS X was determined by FCM and fluorescence microscopy. Results: The A 549 DDP cell line was 8.9 fold resistance relative to the parental A 549 cell line. The formation of ICL in A 549 was 6.28 times higher than that in A 549 DDP cells. The intracellular and intranuclear accumulation of cisplatin in A 549 cells was 5.9 times and 4.1 times higher than that in A 549 DDP cells, respectively. The ability of GS X pump pumped GS X complex (GS Pt) in A 549 DDP cells was higher than that in A 549 . The repair rate in A 549 DDP cells was 2 times higher than that in A 549 . Conclusions: Decreased accumulation and increased export of cisplatin might be the main mechanism of cisplatin resistant A 549 DDP cells while the enhanced repair capacity of DNA may play a role in CDDP resistance.