Notch1基因在T-ALL患者中的表达及其对NF-κB通路的影响

Expression of Notch1 gene in T-ALL patients and its effect on NF-κB pathway

目的:探讨Notch1基因在急性T淋巴细胞白血病(T-ALL)患者外周血单个核细胞(PBMC)中的表达及其对NF-κB通路的作用。方法:选取T-ALL患者67例作为试验组,以67例健康体检者作为对照。采用qRT-PCR分析PBMC中Notch1和NF-κB通路(IκBα、IKKβ)mRNA表达量,分析Notch1的表达水平与T-ALL患者临床指标和预后之间的关联,以及Notch1与NF-κB通路mRNA表达水平的关联。沉默Jurkat细胞中的Notch1基因,qRT-PCR分析Notch1、IκBα和IKKβ mRNA表达,Western blot分析Notch1、磷酸化IκBα(p-IκBα)和磷酸化IKKβ(p-IKKβ)蛋白表达。结果:T-ALL组PBMC中Notch1 mRNA表达水平高于健康组,差异有统计学意义(P<0.05)。Notch1表达水平与LDH水平、白细胞水平和危险度分级之间呈显著正相关(r=0.102,P=0.025;r=0.247,P=0.019;r=0.429,P=0.006),而与年龄和性别无显著相关性。Notch1与IκBα mRNA水平呈显著负相关(r=-0.754,P=0.039),与IKKβ mRNA水平呈显著正相关(r=0.738,P=0.002)。Notch1低表达组中位总生存时间为(18.5±2.2)个月,显著长于高表达组的(12.7±3.4)个月(χ;=1.677,P=0.038)。沉默Notch1可显著上调IκBα mRNA和p-IκBα蛋白水平(P<0.05),显著下调IKKβ mRNA和p-IKKβ蛋白水平(P<0.05)。结论:Notch1基因在T-ALL患者血浆PBMC中高表达,与患者LDH水平、白细胞水平和危险度分级等临床指标和生存率相关,Notch1可能通过NF-κB通路发挥作用。

Objective:To investigate expression of Notch1 gene in peripheral blood mononuclear cells(PBMC)of patients with acute T lymphocytic leukemia(T-ALL)and its effect on NF-κB pathway.Methods:Sixty-seven T-ALL patients were selected as experimental group,and 67 healthy subjects were selected as control group. mRNA expression levels of Notch1 and NF-κB pathway(IκBα and IKKβ)in PBMC were analyzed by qRT-PCR,correlation between expression level of Notch1 and clinical indicators and prognosis of T-ALL patients was analyzed,and correlation between mRNA expression levels of Notch1 and NF-κB pathway were analyzed.Notch1 gene in Jurkat cell line was silenced,mRNA expressions of Notch1,IκBα and IKKβ were analyzed by qRT-PCR. Expressions of Notch1,phosphorylated IκBα(p-IκBα)and phosphorylated IKKβ(p-IKKβ)protein were analyzed by Western blot.Results:Expression level of Notch1 mRNA in PBMC of T-ALL group was higher than that of healthy group,and the difference was statistically significant(P<0.05). Notch1 expression level was positively correlated with LDH level,WBC level and risk grade(r=0.102,P=0.025;r=0.247,P=0.019;r=0.429,P=0.006),but there was no significant correlation with age and gender. Notch1 was negatively correlated with IκBα mRNA level(r=-0.754,P=0.039),and positively correlated with IKKβ mRNA level(r=0.738,P=0.002). Median overall survival time of low expression of Notch1 group was(18.5±2.2)months,which was significantly higher than that of high expression of Notch1 group[(12.7±3.4)months](χ~2=1.677,P=0.038). Silencing Notch1 could significantly up-regulate levels of IκBα mRNA and p-IκBα protein(P<0.05),could significantly down-regulate levels of IKKβ mRNA and p-IKKβ protein(P<0.05).Conclusion:High expression of Notch1 gene in plasma PBMC of T-ALL patients is correlated with clinical indicators such as LDH level,leucocyte level,risk grade and survival rate. Notch1 may play a role through NF-κB pathway.