地西他滨对急性白血病患者甲基化凋亡蛋白酶活化因子1基因的去甲基化作用

Demethylation stduy of decitabine in acute leukemia patients with Apaf-1 gene methylated

目的探讨地西他滨去甲基化作用治疗急性白血病患者的有效性。方法通过甲基化特异性PCR选取10例凋亡蛋白酶活化因子1（Apaf-1）基因启动子发生甲基化的患者，经地西他滨治疗后，通过甲基化特异性PCR检测患者Apaf-1基因去甲基化状态。通过反转录PCR检测lO例患者经地西他滨治疗前后骨髓单个核细胞Apaf-1基因mRNA表达情况。结果甲基化特异性PCR检测示，10例患者经地西他滨治疗后，6例发生了去甲基化。治疗前10例患者因甲基化Apaf-1mRNA均表达缺失，经地西他滨治疗后，4例重新表达，6例未表达。治疗后6例Apaf-1 mRNA表达缺失的患者中，4例Apaf-1基因未发生去甲基化，2例发生去甲基化，考虑可能与等位基因缺失或突变有关。结论地西他滨通过使Apaf-1基因启动子去甲基化恢复抑癌基因的表达，发挥其凋亡中的关键因子作用。

Objective To investigate the effectiveness of decitabine demethylation in treatment of acute leukemia. Methods Methylation specific PCR （MSP） was used to detected the methylation status of Apaf-1 gene promoter. 10 cases entering the group. MSP was used to detected the 10 cases methylation status of Apaf-1 promoter between pre and post-treatment of dicitabine. RT-PCR method used was to detect the differential expression levels of Apaf-1 mRNA in acute leukemia bone marrow mononuclear cell between pre- and post- treatment of decitabine. Results In post-treatment of decitabine, 6 cases Apaf-1 gene promoter was demethylated. The loss expression of Apaf-1 mRNA re-expressed in 4 cases. 6 cases Apaf-1 mRNA still express deletion. 6 cases patients have Apaf-1 mRNA exprssion deletion, However, 4 cases Apaf-1 gene was demethylated, 2 cases methylated in post-treatment, maybe related to allele deletion or allelic varriants. Conclusion Post treatment of decitabine. Apaf-1 gene promotor was demethylated and repress the expression of Apaf-1 mRNA, play a key role in apoptosis maybe a new method for treatment of acute leukemia.