Gene expression analysis of Early immature and Late mature T-ALL cell lines

Early immature T-cell acute lymphoblastic leukemias (T-ALLs) account for about 5-10% of pediatric T-ALLs and are associated with poor prognosis. However, the genetic defects that drive the biology of these tumors remain largely unknown. Analysis of microarray gene expression signatures in adult T-ALL demonstrated a high prevalence of early immature leukemias and revealed a close relationship between these tumors and myeloid leukemias. Consistently, adult immature T- ALLs showed characteristic mutations in myeloid specific oncogenes and tumor suppressors including IDH1, IDH2, DNMT3A, FLT3 and NRAS. Moreover, we identified ETV6 mutations as a novel genetic lesion uniquely present in immature adult T-ALL. All together, our results demonstrate that early immature adult T- ALL represents a heterogeneous category of leukemias characterized by the presence of overlapping myeloid and T-ALL characteristics and highlight the role of ETV6 mutations in these tumors.

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Van Vlierberghe P, Ambesi-Impiombato A, Perez-Garcia A, Haydu JE, Rigo I, Hadler M, Tosello V, Della Gatta G, Paietta E, Racevskis J, Wiernik PH, Luger SM, Rowe JM, Rue M, Ferrando AA