10962

MLLT11

AF1Q|RP11-316M1.10;myeloid/lymphoid or mixed-lineage leukemia (trithorax homolog, Drosophila); translocated to, 11;MLLT11;myeloid/lymphoid or mixed-lineage leukemia (trithorax homolog, Drosophila); translocated to, 11

ALL1 fused gene from chromosome 1q|ALL1-fused gene from chromosome 1q|protein AF1q

1q21

protein-coding

The AF1q gene, a mixed-lineage leukemia fusion partner, is highly expressed in hematopoietic progenitor cells but has low expression in differentiated cells. We determined the expression of the AF1q gene by reverse transcriptase-polymerase chain reaction in 64 pediatric acute myeloid leukemia (AML) patients treated on children's cancer Group clinical trial CCG-2891 and correlated its expression level to clinical characteristics and outcome. AF1q expression in patients varied from 0- to 154-fold compared with normal marrow, and increasing expression levelwas associated with worsening survival, with a hazard ratio of 1.02 per fold increase in AF1q expression (P = .032). We divided patients into tertile groups based on AF1q expression level. Patients with high AF1q expression (top tertile)had a higher predominance of French-American-British M1 compared to patients with lower 2 tertiles of AF1q expression (43% vs 9%, P = .003). High AF1q expression was associated with poor survival in univariate and multivariate models. Overallsurvival at 8 years for patients with the high AF1q expression was 19% versus 50% in patients with low AF1q expression, (P = .01). AF1q expression may correlate with clinical outcome in pediatric AML, although it is not clear if AF1q is simply a marker of a more primitive phenotype or contributes directly to leukemogenesis.