实时定量RT-PCR检测白血病细胞B7-H1基因表达及其临床意义

Real-time quantitative PCR detecting B7-H1 gene expression in leukemia cells and its clinical implications

目的检测白血病患者骨髓单个核细胞(BMMNC)B7-H1基因的表达情况,并探讨 B7-H1基因表达的临床意义。方法应用 SYBR Green Ⅰ实时定量 RT-PCR 法(RQ-PCR)检测74例初治白血病患者及10名正常人 BMMNC B7-H1 mRNA 表达情况,并跟踪检测12例化疗后获得完全缓解(CR)和5例复发患者 B7-H1 mRNA 表达情况。对74例白血病患者的临床特征与 B7-H1基因表达水平进行相关性分析。结果初治白血病患者 BMMNC B7-H1 mRNA 表达阳性,但表达水平低于正常人,两组基因定量比较值 RQ 为0.125。诱导化疗获得 CR 后 B7-H1 mRNA 表达水平较治疗前升高,治疗前后两者定量比较值 RQ 为69.070,差异具有统计学意义(P=0.001);复发时 B7-H1 mRNA 表达水平较治疗前亦升高,复发与治疗前比较为4.00。B7-H1基因表达水平与患者性别、年龄、外周血白细胞计数、骨髓中幼稚细胞比例、CD34抗原阳性与否均无相关性,与治疗反应有显著相关性。诱导化疗后未获 CR 的患者,其治疗前 B7-H1 mRNA 表达水平明显高于化疗后获得 CR 的患者,两组定量比较值为26.91(P=0.005)。结论初治白血病患者 BMMNC B7-H1基因呈低水平表达,诱导化疗获得 CR后 B7-H1 mRNA 表达水平较治疗前升高。B7-H1基因表达水平与患者的治疗反应有显著相关性。

Objective To detect the expression of B7-H1 gene in bone marrow mononudear cells （BMMNCs） from leukemia patients and explore its clinical implications. Methods The B7-H1 mRNA expression levels of BMMNCs from 74 newly diagnosed leukemia patients and 10 normal volunteers were detected by real-time quantitative PCR. At the same time, BMMNCs from 12 patients in complete remission （CR） after chemotherapy and 5 in relapse were followed up. The correlation between the clinical features of 74 de novo leukemia patients and the expression level of B7-H1 gene was analyzed. Results The mRNA expression level of B7-H1 gene in BMMNCs from de novo leukemia patients （ RQ = 0. 125 ） was lower than that from normal control （ RQ = 1 ）. When patients achieved CR the gene expression level （ RQ = 69.07 ） was significantly higher than that before CR （P =0. 001 ）. After relapsed, its level （ RQ =4） was still higher than that before CR （ P 〉 0.05 ）. No clinical parameters such as gender, age, peripheral white blood count, blast cells ratio in BM, CD34 positive cells were significantly correlated with the expression level of B7-H1 except the response to therapy. The initial expression level of B7-H1 gene in non CR patients after therapy was significantly higher than that in CR patients （ RQ = 26.91, P = 0. 005 ）. Conclusion The mRNA expression level of B7-H1 gene in newly diagnosed leukemia patients is lower than that in normal controls, and is higher in CR patients than in newly diagnosed patients. There is a correlation between the gene expression level and responsiveness to therapy.