bcl-2基因和Fas基因与小儿急性淋巴细胞白血病细胞凋亡的关系及其临床意义

研究小儿急性淋巴细胞白血病(ALL)细胞Bcl-2蛋白表达以及特异硫代反义脱氧寡核苷酸(ASON)和抗Fas单克隆抗体(anti-Fas McAb)在诱导白血病细胞凋亡中的作用,采用免疫组织化学法和Western blot法。结果显示,小儿ALL细胞Bcl-2蛋白表达量明显高于正常,ASON和anti-Fas McAb诱使白血病细胞凋亡,且Bcl-2蛋白高表达的白血病患者比bcl-2低表达者对FasMcAb更敏感。结论提示,ASON和anti-Fas McAb可诱导ALL细胞凋亡,这为ALL临床治疗展示了新方向,也为白血病患者自体骨髓移植,体外纯净骨髓或周边血液提供理论依据和实验技术。

Bcl-2 gene and Fas gene in relation vvith apoptosis of childhood acute lymphocytic leukemia cells and its clinical significance

The expression of Bcl-2 protein of ALL celis and the effect of ASON and anti-Fas McAb were studied by using immunohistochemical methods and Western Blot in order to elucidate the relationship between bcl-2 gene and Fas gene in apoptosis. The Bcl-2 protein was detected on 17 samples from untreated childhood ALL, and the result showed that the expression of bcl-2 is much higher in the childhood ALL than in the normai control. Incubation of leukemic cells from untreated ALL children with antisense oligodeoxynucleotides (ASON) directed against bcl-2 mRNA resulted in an obvious decrease in the expression of Bcl-2 prtein and bcl-2 mRNA. In the 17 ALL cases which treated with ASON specific for bcl-2, the decreased expression of bcl-2 was accompanied by increased apoptosis. Leukemic cells were incubated with anti-Fas McAb in different concentration, the apoptotic cells were examined by using Tunnel method. We found that when the concentration of anti-Fas McAb in cellular culture reached to 500 ng/ml, the ALL cells accelerated to apoptosis. ALL cells pretreated with bcl-2 ASON were more easily induced to apoptosis by anti-Fas McAb and leukemic cells with bcl-2 downregulation might be more susceptible to anti-Fas McAb. It was concluded that the application of both bcl-2 ASON and anti-Fas McAb could provide effective methods for clinical treatment of childhood ALL and purging leukemic blasts from bone marrow graft for autologous transplantation.