儿童急性白血病MLL基因的检测及临床意义

目的对儿童急性白血病(acute leukem ia,AL)MLL基因重排进行临床和实验研究。方法采用荧光原位杂交(FISH)和多重RT-PCR技术,联合染色体R带核型分析及流式细胞仪免疫表型检测,对27例儿童AL进行分析。结果25例儿童AL中的9例(36.0%)有MLL重排,ALL中的发生率为4.0%,AML中的发生率为3.7%。多重RT-PCR检测到MLL易位产生的融合基因4例,分别为MLL/AF4 2例、MLL/AF9和MLL/AF10各1例;27例白血病患儿进行了染色体核型分析,22例(81.5%)有克隆性染色体异常。在MLL重排中ALL均为B系ALL,AML均为M5b。结论MLL基因重排可能与儿童急性单核细胞白血病和B细胞系ALL有关。

Detection of MLL gene rearrangements in childhood acute leukemia and its clinical significance

Objective To study the clinical and laboratory features of childhood acute leukemia with MLL gene rearrangements.Methods Twenty-seven cases of childhood patients were studied by Dual-Color FISH,Multiplex RT-PCR in combination with R banding karyotypic analysis and immunophenotye assay for cells by flow cytometry.Results Of 25 cases of childhood AL receiving FISH detection,9(36%) had MLL rearrangements.The frequency of MLL rearrangements from genetic abnormalities in childhood ALL and AML were 4% and(3.7%) respectively.Four cases were found having MLL rearrangements by multiplex RT-PCR,including MLL/AF4(2 cases),MLL/AF9 and MLL/AF10(one case for each).Twenty-two cases(81.5%) were found to have chromosome abnormalities.Among them all the MLL rearrangements were from B-ALL and AML-M5b.The 4 of the 9 cases with MLL rearrangements were treated by chemotherapy and obtained complete remission(4/9,44.4%).Conclusion MLL rearrangements may be associated with AML-M5 and B-ALL.