B-ALL患者PTEN表达及其启动子甲基化状态研究  

Research on PTEN Expression and Its Promoter Methylation in B-ALL Patients

作　　者：杨晶[1] 杜雯[1] 贺艳丽[1] 刘隽[1] 郑金娥[1] 黄士昂[1] 

机构地区：[1]华中科技大学同济医学院附属协和医院,武汉430022

出　　处：《内科急危重症杂志》2007年第4期141-143,共3页Journal of Critical Care In Internal Medicine

基　　金：国家自然基金杰出青年基金(No:30225038)

摘　　要：目的:探讨抑癌基因PTEN在急性B淋巴细胞白血病(B-ALL)患者外周血单个核细胞中的表达及其与启动子甲基化状态之间的关系。方法:收集24例初发B-ALL患者和25例正常人外周血单个核细胞,通过Kol-mogorov-Smirnov(KS)分析,利用定量流式细胞术检测PTEN表达。提取基因组DNA后,采用MSP方法检测PTEN启动子甲基化状态,进而在体外培养过程中,以DNA甲基化转移酶抑制剂5-氮-2’脱氧胞嘧啶进行处理,观察其对B-ALL单个核细胞PTEN表达的影响。结果:25例正常人外周血单个核细胞均表达PTEN,KS分析时D值为0.941±0.017,而24例B-ALL患者中22例(91.6%)外周血单个核细胞PTEN表达明显缺失,D值仅为0.546±0.115,两者差异具有显著性意义(P<0.01);正常人和PTEN高表达的B-ALL患者外周血单个核细胞中未发现PTEN启动子发生甲基化修饰,而PTEN表达缺失的B-ALL患者中有5例(22.7%)出现PTEN启动子甲基化,将其单个核细胞培养时以5-氮-2’脱氧胞嘧啶处理4d,PTEN表达明显升高。结论:PTEN的表达缺失在B-ALL患者中很常见,其启动子甲基化导致的PTEN表达缺失在B-ALL的发生中可能起重要作用。Objective： To study the expression of tumor suppressor PTEN in peripheral blood blast cells of B- ALL patients and involvement of promoter methylation in patients with loss of PTEN expression. Methods： Kolmogorov Smimov （KS） statistical test was used to characterize the expression of PTEN in peripheral blood mononuclear cells from both healthy donors and B-ALL patients in quantitative flow cytometry analysis. PTEN Promoter Methylation status of genomic DNA extracted for the peripheral blood mononuclear cells was determinded by MSP analysis. The cells were treated with 5-Aza-2＇deoxycytidine for 4 days to study its effect on restoring PTEN expression in B-ALL blast cells. Results： Compared with the high level PTEN expression in healthy donors （D value 0. 941 ± 0. 017）, PTEN expression could barely be detected in 22（91.6%） B-ALL patients （D value 0. 546 ± 0. 115）, there was significant difference between them （P〈0. 01 ）. PTEN Promoter Methylation was detected in 5 patients （22. 7%）but not in any healthy donor. Moreover, 5-Aza-2＇ deoxycytidine treatment could restore the PTEN epxression in these patients. Conclusion： Low/absent expression of PTEN is a frequent event in B-ALL patients and promoter Methylation may contribute to the loss of PTEN epression in some of B-ALL patients.

关 键 词：BALL PTEN 甲基化 5-氮-2’脱氧胞嘧啶 

分 类 号：R733.7[医药卫生—肿瘤]