Figure 1.

Metaphase karyotype from initial diagnosis (A) and fluorescence in situ hybridization performed at relapse (B) showing biallelic inversion of chromosome 3 (arrows). Also shown are two intact copies of chromosome 7 in this patient (A). Mononuclear cells isolated by Ficoll gradient separation from bone marrow aspirate (C) and peripheral blood (D) were treated ex vivo for 48 h with the indicated doses of arsenic trioxide (ATO) and darinaparsin (Dar) to assess sensitivity to arsenicals. Cell death was measured as the percentage of cells with sub-G₀ DNA content. Error bars indicate SEM.