To identify genes whose expression correlated with biological features of therapy-related AML (t-AML), we analyzed the expression profiles of de novo AML t(9;11) and t-AML t(9;11) bone marrow samples using previously published SAGE data. Three-hundred twenty-nine transcripts that satisfied statistical (P<0.05) and magnitude-of-change ($geq$ 4-fold) criteria were identified as differentially expressed between de novo AML t(9;11) and t-AML t(9;11) cells. Of these transcripts, 301 (91%) matched known genes or ESTs and were classified according to functional categories (http://david.abcc.ncifcrf.gov/). The majority of differentially expressed genes in t-AML t(9;11) were involved in the regulation of biological and metabolic processes. Especially prominent among these were genes related to immune and drug responses. These results establish a framework for developing new drugs for the treatment of t-AML.