儿童急性淋巴细胞白血病TEL-AML1融合基因的表达水平与临床特点、早期治疗反应的关系

为探讨儿童急性淋巴细胞白血病初诊时TEL-AML1融合基因表达水平与患儿的临床特点、早期治疗反应的关系,采用实时定量聚合酶链反应（RQ-PCR）定量检测35例患儿（包括标危20例,中危15例）初诊TEL-AML1表达水平和诱导缓解治疗结束微小残留病（MRD）水平,比较MRD阴性与MRD阳性患儿的初诊TEL-AML1表达水平及临床特点,分析初诊TEL-AML1表达水平、MRD水平与临床特点、早期治疗反应的相关性。结果发现,初诊时TEL-AML1表达水平为1.63×104拷贝/104拷贝ABL（中位数）。诱导缓解结束时,16例（10例标危、6例中危）患儿未达到分子缓解,MRD水平分别为0.84-282.93拷贝/104拷贝ABL。初诊TEL-AML1表达水平与各临床特点及MRD水平缺乏相关性。MRD水平与泼尼松实验治疗第8天外周血幼稚细胞数显著相关。初诊时外周血白细胞计数〈25×109/L的患儿,MRD水平还与白细胞计数、幼稚细胞百分比显著相关。MRD阴性患儿初诊TEL-AML1表达水平显著低于MRD阳性者。结论：对于TEL-AML1＋儿童ALL,45.71%未能在诱导缓解治疗结束时获得分子缓解,说明了后续治疗的重要性。泼尼松实验治疗的效果预示了诱导缓解治疗结束时的MRD水平。初诊外周血白细胞计数、幼稚细胞百分比和初诊TEL-AML1表达水平均在一定程度上影响诱导缓解治疗结束时的MRD水平。

Relation between TEL-AML1 Expression Level and Clinical Characteristics as well as Early Response to Treatment in Children with Acute Lymphoblastic Leukemia

The study was aimed to investigate the relation between the expression level of TEL-AML1 (translocation ETS leukemia-acute myeloid leukemia 1) fusion gene and clinical characteristics as well as early response to treatment in children with ALL (acute lymphoblastic leukemia). With real-time quantitative polymerase chain reaction (RQ-PCR), the expression level of TEL-AML1 at diagnosis and MRD (minimal residual disease) at the end of induction of remission were detected in 35 children with ALL, including 20 SR (standard risk) and 15 IR (intermediate risk) patients. The expression level of TEL-AML1 and clinical characteristics at diagnosis were compared between MRD negative and MRD positive patients. The relation between TEL-AML1 expression levels at diagnosis, MRD level and clinical characteristics as well as early response to treatment were also explored. The results indicated that the expression levels of TEL-AML1 at diagnosis were 1.63 x 10(4) copies/10(4) copies ABL (median). At the end of induction of remission, 16 patients (10 SR and 6 IR patients) did not achieve molecular remission, whose MRD levels were 0.84 - 282.93 copies/10(4) copies ABL. No relation was found between expression levels of TEL-AML1 at diagnosis and clinical characteristics as well as MRD level. There was a significant relation between MRD level and blast count in peripheral blood (PB) at day 8 after prednisone trial induction. Significant relations between MRD level and presenting leukocyte count, blast percentage in PB were also found in the patients with presenting leukocyte count < 25 x 10(9)/L. TEL-AML1 expression level at diagnosis of MRD negative patients was lower than that of MRD positive ones. It is concluded that therapy after induction of remission is of importance by the fact that 45.71% children with TEL-AML1(+) ALL did not achieve molecular remission at the end of induction of remission. The effectiveness of prednisone trial predicts the MRD level. In addition, presenting leukocyte count, blast percentage in PB and TEL-AML1 expression level at diagnosis may have an effect on MRD level to some extent.