Global gene expression profile of dasatinib-resistant RCH-ACV cells

Purpose: Several ALL subtypes have been described depending on their karyotype, cell type, immunophenotype and gene-expression profile. Recently, a novel ALL subtype has been described and is characterized by expression of the pre-B cell receptor (pre-BCR). Interestingly, half of the cases is associated with the chromosomal translocation t(1:19), coding for the chimeric fusion protein E2A-PBX1, which is present in about 5% of pediatric and adult ALL. Using preclinical models, we and other groups have shown very promising preclinical activity of dasatinib in pre-BCR+ ALL and early clinical evidence supports our observations. To study mechanism of acquired dasatinib resistance, we generated dasatinib-resistant pre-BCR+/E2A-PBX1+ cell lines through multiple passages in the presence of increasing drug concentrations. Whole transcriptome analysis of dasatinib-sensitive and resistant ALL cells were performed to detect systematically differentially expressed genes and enriched pathways involved in dasatinib resistance. Overall design: RNA was isolated at three different time points (replicates) from two independent generated dasatinib-resistant RCH-ACV sublines. Replicates from control dasatinib-sensitive RCH-ACV cell sublines were used as controls.