Ikeda K, Sasaki K, Tasaka T, Nagai M, Kawanishi K, Takahara J, Irino S
Department of Transfusion Medicine, Kagawa Medical School, Japan.
Am J Hematol. 1994 Mar;45(3):212-6. doi: 10.1002/ajh.2830450304.
Chromosome translocation t(15;17), the breakpoints of which are in the PML gene on chromosome 15 and retinoic acid receptor-alpha (RAR alpha) gene on chromosome 17, is specifically found in acute promyelocytic leukemia (APL). Clinically typical APL without t(15;17) and with the PML-RAR alpha fusion transcripts or rearrangements in PML and/or RAR alpha gene has been reported, suggesting submicroscopic changes at the molecular level without apparent t(15;17) or observation of normal metaphases. Trisomy 8 is common in APL as a secondary chromosomal abnormality in addition to t(15;17), as well as in acute myelogenous leukemia in general, but it is rare as a sole chromosomal anomaly in APL. PML-RAR alpha fusion transcript was detected in an APL case with trisomy 8 but without t(15;17), indicating that the leukemic cells lacked t(15;17) and still expressed the PML-RAR alpha fusion transcripts. This indicates that the same submicroscopic molecular changes as in APL with t(15;17) do occur in APL without t(15;17) and supports the use of molecular analysis for PML-RAR alpha fusion in APL.
染色体易位t(15;17)，其断点位于15号染色体上的早幼粒细胞白血病基因(PML)和17号染色体上的维甲酸受体α(RARα)基因，在急性早幼粒细胞白血病(APL)中特异性发现。临床上已报道了无t(15;17)但有PML-RARα融合转录本或PML和/或RARα基因重排的典型APL，提示在分子水平存在亚显微变化，而无明显的t(15;17)或正常中期的观察。除t(15;17)外，8号染色体三体在APL中作为继发性染色体异常很常见，在急性髓性白血病中一般也常见，但在APL中作为唯一的染色体异常则很少见。在一例有8号染色体三体但无t(15;17)的APL病例中检测到PML-RARα融合转录本，表明白血病细胞缺乏t(15;17)但仍表达PML-RARα融合转录本。这表明在无t(15;17)的APL中确实发生了与有t(15;17)的APL相同的亚显微分子变化，并支持对APL中PML-RARα融合进行分子分析。
