急性单核系白血病M4/M5中MLL基因重排的间期荧光原位杂交研究

目的　探讨间期荧光原位杂交 ( fluorescence in situ hybridization,FISH)技术对混合谱系白血病 ( mixed lineage leukemia,ML L)基因重排检测的价值 ;评估 ML L 重排在急性单核系白血病 M4 / M5中的发生率和预后意义。方法　采用骨髓直接法或短期培养法制备染色体 ,应用 R显带技术进行核型分析。采用地高辛标记的跨越 11q2 3断裂位点的单色 ML L探针和间期 FISH技术对 2 3例急性单核系白血病M4 / M5病例进行 ML L重排检测。结果　 R显带揭示 2 3例中 7例有涉及 11q2 3的易位 ,5例有其他核型异常 ,10例核型正常 ,1例核型分析失败。 FISH研究显示 12例有 ML L重排 ,包括 R显带检出 11q2 3异常的7例。结论 FISH技术检测 ML L重排的敏感性明显高于常规细胞遗传学技术 ;ML L重排与急性单核系白血病 M4 / M5高度相关 ,是预后不良的指标

Study on mixed lineage leukemia gene rearrangement in AML-M4/M5 by interphase fluorescence in situ hybridization

Objective To explore the value of fluorescence in situ hybridization (FISH) in the detection of mixed lineage leukemia (MLL) rearrangement and to assess the incidence and prognostic significance of MLL gene rearrangement in AML-M4/M5. Methods Bone marrow chromosome preparation of 23 cases of acute myeloid leukemia(AML) consisting of 19 cases with M5 and 4 cases with M4 was made using direct method or short-term culture. Karyotypic analysis was carried out by R-banding technique. Dig labeled 11q23 probe which spans the breakpoint cluster region in MLL was used to detect the MLL rearrangement in the above 23 cases. Results R-banding karyotyping analysis revealed 11q23 translocation in 7 cases, while FISH analysis detected MLL rearrangement in 12 cases including the above 7 cases. Conclusion Interphase FISH was more sensitive in detecting the MLL rearrangement in AML-M4/M5, compared with the conventional cytogenetic method. MLL rearrangement is highly related to AML-M4/M5; it is an indication of poor prognosis.