目的 探讨bcl-2基因过表达导致人急性髓系白血病对柔红霉素耐药的机制。方法 通过分子克隆技术构建质粒pcDNA3.1(+)/bcl-2,将其转染人急性髓系白血病U937细胞,分正常对照组、空载体对照组、转染组,与柔红霉素培养24h,采用CCK-8法检测细胞增殖率,Western blot检测凋亡相关蛋白的表达变化,从而比较转染bcl-2基因前后,U937细胞对柔红霉素敏感性的变化。结果 成功构建质粒pcD-NA3.1(+)/bcl-2,转染入U937细胞,PCR证实其转染效果;CCK-8法检测结果显示U937/bcl-2组细胞存活率显著高于对照组和空载体对照组;bcl-2基因过表达降低caspase-3片段的裂解活化,降低U937细胞对柔红霉素的敏感性。结论bcl-2过表达抑制caspase-3激活、抑制柔红霉素杀伤U937细胞,导致细胞对柔红霉素耐药。bcl-2可作为临床治疗急性髓系白血病的靶点。
Objective To explore the relationship between bcl-2 over - expression with the resistance to daunorubi- cin in acute myeloid leukemia(AML) cell line U937. Methods Construction of pcDNA3.1 ( + )/bcl-2, and then pcDNA3.1 ( + )/bcl-2 and pcDNA3. 1 ( + ) were transfected into U937 cell line. The cells were devided into 3 groups: U937,U937/NC,U937/bcl-2. These groups were exposed to daunorubicin for 24 h. The growth inhibitory effects of daunorubicin were evaluated by CCK-8. Expression of apoptosis - related proteins was determined by- Western blot. Results Survival rate of cells in U937/ bcl-2 group was markedly higher than cells in U937 and U937/NC groups. The enhanced caspase-3 activity was High expression of bcl-2 inhibits activation of caspase-3 and generation of drug resistance.