bcl-2反义寡核苷酸对白血病细胞药物敏感性的影响

Effect of bcl-2 Antisense Oligodeoxynucleotieds on Drug-sensitivity of Leukemic Cell Line U937

目的 探讨 bcl- 2基因反义寡核苷酸 (ASODN)对白血病细胞药物敏感性的影响。 方法 MTT法测bcl- 2 ASODN对 U 937细胞足叶乙甙 (VP1 6 )敏感性 ,计算细胞存活率 ,绘制剂量 -效应曲线 ,直线回归求半数致死量 IC50 ;DNA电泳、AO/ EB荧光染色测定细胞凋亡率。 结果 VP1 6与 bcl- 2 ASODN联合作用比单独用 VP1 6或 VP1 6与 SODN细胞存活率显著减少。 bcl- 2 ASODN作用后 VP1 6对 U 937细胞的 IC50 由 7.93μoml/ L降至2 .6 7μom l/ L。与单独 VP1 6作用组相比 ,bcl- 2 ASODN与 VP1 6联合作用后梯状 DNA片段明显增加 ,细胞凋亡率增高。 结论 bcl- 2 ASODN能促进 VP1 6诱导的白血病细胞凋亡 ,提高白血病细胞对 VP1 6的敏感性。bcl- 2反义寡核苷酸在克服化疗药物耐药性方面 ,具有良好的应用前景。

Objective To explore the effect of antisense oligodeoxynucleotide(ASODN) of bcl|2 gene on chemotherapy sensitivity and on apoptosis of leukemic cell line U937, which was of bcl|2 overexpression. Methods MTT colorimetric assays was used to detect cytotoxicity. The morphologic signs of apoptosic cells observed by light microscope. The DNA fragment analysed by electrophoresis. The proportion of apotosis cells detected by acridine orange and ethidium bromides(AO/EB) stains. Results There was a significant decrease of survival rate after expose to combintion of bcl|2 ASODN with VP16, compared VP16 alone or combination of sense oligodeoxynucleotide with VP16. After incubation with bcl|2 ASODN, IC-{50}of etoposide on U937 cell line decreased from 4 65 μmol/L to 1 35 μmol/L, ladder|like pattern on agorose gel eletrophoresis indicated bcl|2 ASODN induced U937 cells more sensitive to {etoposide} induced apoptosis. The rate of apoptosis elevated from (19±2 3)% to (32±1 8)%. {Conclusion} bcl|2 ASODN enhances the sensitivity of U937 cell line to etoposide, increase etoposide induced apoptosis. bcl|2 ASODN provide a potential mothod for treatment of hematologic maligancy, especially for overcome chemoresistance.