Development of a new classification depend on epigenetic information in pediatric acquired bone marrow failure syndrome

再生障碍性贫血（AA）和发育不良骨髓增生异常综合征（MDS）的鉴别诊断，特别是儿童期难治性细胞减少症（RCC）的鉴别诊断仍然很困难。激光显微解剖系统切割的9例RCC标本中有6例TP53阳性染色细胞出现TP53基因突变，而AA标本中未发现TP53基因突变。此外，5个RCC标本中有2个在p16基因启动子区域显示高度甲基化状态，而AA标本中没有。Evi-1、GATA-2和AML1/RUNX1的表达高于AA/MDS期。我们还发现在这一过程中发生了AML1/RUNX1和N-RAS突变。

The differential diagnosis between aplastic anemia(AA) and hypoplastic myelodysplastic syndrome(MDS), especially, refractory cytopenia of childhood(RCC) is still difficult. Six of 9 RCC specimens showed the TP53 gene mutation in TP53 positive stained cells cut by lazer microdissection system, however, there is no TP53 mutation in AA specimens. Furthermore, 2 of 5 RCC specimens showed the highly methylated status in the promotor region of p16 gene, but not in AA specimens. Higher expression of Evi-1, GATA-2 and AML1/RUNX1 were found than those at AA/MDS phase. We also found AML1/RUNX1 and N-RAS mutations occurred in this process.