急性髓系白血病干细胞免疫表型和信号通路蛋白活化检测及意义

摘要

目的 为了解急性髓系白血病干细胞( AML - LSCs)免疫表型特点和信号转导通路活化状态,以探讨其生物学特征.方法 应用流式细胞术检测( AML - LSCs)免疫表型、P-gp、PTEN、p- Akt、p - ERK的表达,以正常造血干细胞(HSCs)为对照.结果 正常HSCs主要免疫表型:CD34+、CD38-、CD123-、CD96- 、CD117+、CD44+、CD33-、CD13-.PTEN蛋白阳性率为72.09％,p- Akt及p- ERK蛋白均阴性,P-gp蛋白阴性.AML - LSCs主要免疫表型:CD123+、CD96+、CD117-、CD44+、CD13+、CD33+,与HSCs免疫表型差异主要为CD123+、CD96+、CD117 -、CD13+、CD33+.LSCs PTEN蛋白阳性率为25.58％,低于正常HSCs(x2=30.88,P＜0.01),p- Akt阳性率为63.95％,p- ERK阳性率为70.93％,高于正常HSCs(x2 =24.43、30.87,P均＜0.01).P- gp蛋白阳性率为67.44％.79例AML患者预后分析表明,高AML - LSCs的患者较低AML - LSCs患者复发率增高(x2=5.69,P＜0.05)；无病生存率(DFS)分析显示,高AML - LSCs的患者无病生存时间中位数14个月,较低AML - LSCs患者无病生存时间中位数28个月明显缩短(P＜0.01).结论 LSCs免疫表型特征为CD34+、CD38 -、CD123+、CD96+、CD117-,P - gp高表达.AML - LSCs数量高的AML患者复发率高、无病生存时间短、预后差.MEK/ERK,PI3 K/PTEN/Akt信号通路被激活,可能与LSCs克隆性增殖和自我更新有关.%Objective To investigate the characteristics of the immunophenotype and the status of signal transduction proteins in a-cute myeloid leukemia leukemic stem cells ( AML - LSCs). Methods Immunophenotype and P - gp, PTEN, p - Akt, p - ERK of the AML - LSCs were analyzed by flow cytometry. Normal hematopoietic stem cells ( HSCs) were taken as the normal control. Results The immunophenotype for the HSCs were CD34 +, CD38 - , CD123-, CD96- , CD117-, CD44-CD33- and CD13-. 72.09% of the HSCs was found to be PTEN positive, while p - Akt, p - ERK and P - gp was absent in HSCs. The major immunophenotype for the AML -LSCs were CD123 + , CD96+, CD117- , CD44 +, CD13 + and CD33+. Compared to the HSCs, the characteristic phenotype for the AML -LSCs were CD123 +, CD96+, CD117- , CD13 + and CD33 +. The percentage of PTEN was significantly lower in AML - LSCs (25. 58% ) than that of the HSCs (j-2 = 30. 8, P < 0. 01 ). The expression of p - Akt (64. 0% ;X2 = 24. 43 , P < 0. 01 ) and p - ERK (70. 9% ; X2 = 30. 87, P < 0. 01) was significantly higher in AML - LSCs than in HSCs. Furthermore, P - gp expression was observed in 67.44% patients. Among 79 AML patients, the relapse rate in patients with high AML - LSCs proportions was markedly increased than in those with low AML - LSCs proportions (X2 =5.69, P<0.05) , and the dease -free survival (DFS) was significantly decreased in patients with high AML - LSCs percentage than in those with low AML - LSCs percentage ( median: 14 months vs 28 months, P < 0. 01). Conclusion The characteristic immunophenotype for the AML - LSCs were CD34 +, CD38 - , CD123 +, CD96+, CD117 -, and P - gp protein positive. Patients with high AML - LSCs percentage were associated with high relapse rate, decreased DSF. Furthermore, the activation of the MEK/ERK, PI, K/PTEN/Akt signal transduction pathway might be involved in the clonal proliferation and self - renewing for the LSCs.