黑色素瘤特异性抗原基因在儿童急性白血病中的表达及初步应用

The expression of PRAME in children with acute leukemia and its clinical applications

目的探讨急性白血病(AL)儿童骨髓及外周血单个核细胞(MNC)中黑色素瘤特异性抗原(PRAME)基因表达情况,以及用于微小残留病监测的临床意义。方法釆用半定量逆转录聚合酶链反应(RT-PCR)方法检测31例初发、6例复发、10例完全缓解期AL儿童骨髓及外周血PRAME mRNA的表达情况,同时检测10例非血液系统恶性疾病患儿骨髓、5例正常成人外周血中PRAME mRNA的表达情况,分析该基因与疗效、预后之间的关系。结果 37例初发及复发AL病例中15例PRAME mRNA表达阳性(40.5%),其中在急性淋巴细胞白血病(ALL)组、急性髓系白血病(ANLL)组的阳性率分别为37.9%、50.0%,两组比较差异无显著性(P>0.05)。在初发组及复发组的表达率分别为38.7%、50.0%,两组比较差异无显著性(P>0.05)。10例完全缓解期及15例对照组病例中PRAME mRNA表达均阴性。PRAME基因表达阳性的患儿完全缓解率(CR)显著低于表达阴性的患儿(CR率分别为60.0%,90.99%,P=0.042)。随访1例初诊PRAME基因表达阳性的ALL患儿,经化学治疗达完全缓解后PRAME基因表达转阴。结论 PRAME基因可在AL患儿中呈阳性表达,并可随疾病的缓解情况逐渐降低或转阴。因此,PRAME基因作为儿童AL的一个重要基因标记物,动态监测其表达水平在评估疗效、判断预后、预测复发方面有一定的意义。

Objective The purpose of this study was to investigate PRAME （ Preferentially antigen of melanoma） mRNA expression levels in bone marrow and peripheral blood mononuclear cells of children with acute leukemia（AL） and its clinical significance for monitoring minimal residual disease. Methods The expression of PRAME gene was measured by semi-quantitative reverse transcriptase polymerase chain reaction （RT-PCR） in the bone marrow and peripheral blood samples of 31 children with newly diagnosed acute leukemia, 6 in relapse, 10 at complete remission and A control group of 10 samples of non-malignant disease patients, 10 peripheral blood samples of healthy donors. And to analyze the relationship between PRAME expression levels and curative effect, prognosis. Results Overexpression of PRAME mRNA was found in the 15 of 37 newly diagnosed and in relapse children（40. 5% ）. In ALL group and ANLL group, PRAME mRNA expression rate were 38% and 50% separately, the two groups of comparisons no statistically significant difference （P 〉 0. 05 ）. In the newly diagnosed relapse group, PRAME mRNA expression rate were 39% and 50% separately, no statistically group and significant difference was found（P 〉 0. 05）. Complete remission rate was lower in PRAME positive children （60. 0% ） than in PRAME gene negative gruop （90. 9% ,P =0. 042）. Follow-up 1 child with overexpression of PRAME gene, .after one course of chemotherapy, the child achieved complete morphologic remission, and PRAME gene can not be measured. Conclusion our results suggest PRAME gene overexpress in newly diagnosed and relapsed acute leukemia children, and dynamic changes with the disease relief Therefore, PRAME gene can be a maker gene of acute leukemia. Dynamiclly detecting PRAME expression at a certain extent can help us assess curative effect, judge prognosis, estimate relapse.