In vitro and in vivo effects of 5-aza-2'-deoxycytidine (Decitabine) on clonogenic cells from acute myeloid leukemia patients.

5-Aza-2'-deoxycytidine (Decitabine) is an analog of deoxycytidine now entering clinical trials in acute myeloid leukemia (AML) owing to a defined antileukemic activity mediated at least in part by DNA hypomethylation, altered gene expression, and induction of cell differentiation. In the present study, we examined the relationship between the in vitro sensitivity to Decitabine of blast progenitors and the clinical outcome, in nine AML patients treated in vivo with Decitabine within a phase II trial carried out at two different institutions. Leukemic blast progenitors in acute myeloid leukemia (AML) undergo terminal divisions giving rise to colonies in methylcellulose