Objective: To investigate the effect of BAX gene deletion on the sensitivity of BCR-ABL-induced B-ALL cells of mice to imatinib and the related mechanism.
Methods: The target gene-knock out (BAX-/-) mice were used as bone marrow cell donors; the wild type bone marrow cells(B6BM) and BAX-/- bone marrow cells(B6BM-BAX-/-) of mice were transfected by using reverse transcription virus, then the BCR-ABL transfected B6BM cells and B6BM-BAX-/- cells were treated with imatinib at different concentration (0,0.5, 1.0 and 2.0 μmol/L) for 48 hours. The number of viable cells was detected by trypan blue, the flow cytometry was used to detect the cell apoptosis, the Western blot was used to detect the changes of BAX, Caspase expression.
Results: In BCR-ABL transfected bone marrow cells treated with imatinib, the numbers of viable cells of BAX deletion group was significantly higher than that of wild type groups with statristcal difference(P<0.05), and effect- and dose-dependency(r=-0.9533 for BAX deletion group, and r=-0.9812 for wild type group). The flow cytometry showed that the cell apoptosis in BAX deletion group signifincantly decreased, compared with wild type group(P<0.05). The Western blot showed that the expression of apoptotic protein Caspase 3 in BAX deletion group was significantly higher than that in wild type group(P<0.05).
Conclusion: BAX deletion can reduce the sensitivity of BCR-ABL-induced B-ALL cells to imatinib.
题目: BAX基因缺失降低BCR-ABL诱导的小鼠B-ALL细胞对伊马替尼的敏感性.
目的: 探讨BAX基因缺失对BCR-ABL诱导的过表达的骨髓细胞对伊马替尼的敏感性影响及相关机制.
方法: 以目的基因敲除小鼠作为骨髓细胞供体；通过逆转录病毒感染B6BM、 B6BM-BAX-/-细胞；用伊马替尼不同浓度（0、05、1.0和2.0 μmol/L）梯度下处理BCR-ABL感染的细胞48 h；台盼蓝对存活细胞计数；采用流式细胞术检测细胞凋亡情况；通过Western blot 检测BAX、Caspase蛋白表达的变化.
结果: 伊马替尼处理BCR-ABL转染的骨髓细胞中，BAX缺失组的存活细胞明显多于野生型，差异具有统计学意义（P＜0.05），效应呈剂量依赖关系(B6BM-BAX-/-组r=-0.9533，B6BM组r=-0.9812)；流式细胞术检测结果表明，BAX基因缺失组比野生型细胞凋亡明显减少，差异具有统计学意义（ P＜0.05）；Western blot结果显示，BAX基因缺失组凋亡蛋白caspase3表达水平明显高于野生型组（P＜0.05）.
结论: BAX缺失可降低BCR-ABL诱导的B-ALL细胞对伊马替尼的敏感性.