BCR and leukemia: Four human leukemia cell lines with different genetic background were selected and initially characterized by western blot to confirm the presence of candidate chimeric proteins: NALM6 and ALL-SIL cells were chosen because they harbor the gene fusions ETV6-PDGFRB (Matheson and Hall, 2003) and NUP214-ABL1 respectively, both belonging to the BCR-ABL1 like aberrations and both leading to ABL1 pathway overactivation (Zhou and Yang, 2014).