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. 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.