Abstract 2243: Gene expression signature of aneuploidy in acute myeloid leukemia

Abstract

Abstract Acute Myeloid Leukemia (AML) is a heterogeneous malignancy characterized by the expansion of myeloid precursor cells with limited or abnormal differentiation capacity. A relatively common event in AML is represented by chromosome gain or loss. Numerical chromosome abnormalities, which define the aneuploid condition, have a detrimental effect in primary non-malignant cells, since they dramatically reduce cellular fitness. However evidence suggests that they have a causative role in tumorigenesis and that they are well tolerated in transformed cells belonging to the myeloid lineage. Aim of the study is to elucidate the pathogenic mechanisms that sustain and contribute to aneuploidy in AML. We have performed gene expression profile (GEP) analysis of bone marrow cells from 42 AML patients, including 19 aneuploid cases and 23 cases with normal karyotype. All samples contained more than 80% blast cells. The aneuploid cohort included AML cases carrying one (or more) monosomy, trisomy or a monosomal karyotype. Our analysis covered more than 245,000 and 40,000 coding and non-coding transcripts, respectively (the latter comprising microRNAs), and a significant number of exon-exon junctions, which allow the analysis of multiple splicing isoforms. Quality controls confirmed that the data show comparable signal values. The gene expression signature of aneuploid samples have been compared to normal karyotype ones. We have identified a set of coding and non-coding transcripts which are differentially expressed between the two groups (p≤0.05, including more than 20 genes with a fold difference ≥2) and defined a gene signature that allows the discrimination between aneuploid and euploid samples in our dataset. The analysis of an increased number of cases will confirm the results and allow the sub-stratification of aneuploid samples according to their GEP. Our data will be further validated by comparing them with published GEP datasets and the gene signature will be characterized by pathway analysis. This study provides novel insights into the molecular mechanism that sustain aneuploidy in AML. The biological validation of genes which are commonly and specifically deregulated in aneuploid AML patients will guide the design of future therapeutic strategies targeting key players in the disease. Acknowledgements: European LeukemiaNet, AIRC, AIL, Prin 2010-2011, FP7 NGS-PTL project. Citation Format: Giorgia Simonetti, Antonella Padella, Viviana Guadagnuolo, Cristina Papayannidis, Francesca Volpato, Emanuela Ottaviani, Serena Formica, Annalisa Astolfi, Ilaria Iacobucci, Giovanni Capranico, Daniel Remondini, Giovanni Martinelli. Gene expression signature of aneuploidy in acute myeloid leukemia. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2243. doi:10.1158/1538-7445.AM2014-2243