Gene expression profiling of chronic myeloid leukemia with variant t(9;22) reveals a different signature from cases with classic translocation.. Homo sapiens

The t(9;22)(q34;q11) generating the Philadelphia chromosome and the BCR/ABL1 fusion gene represents the cytogenetic hallmark of chronic myeloid leukemia (CML). About 5–10% of CML cases show variant translocations with the involvement of other chromosomes in addition to chromosomes 9 and 22. The molecular bases of differences between CML patients with classic and variant t(9;22) have never been elucidated. In this study, we performed gene expression microarrays analysis to compare CML patients bearing variant rearrangements and those with classic t(9;22)(q34;q11). We identified a list of 59 differentially expressed genes significantly associated with the two analyzed groups. These genes are mostly involved in the intracellular protein kinase cascade and their upregulation enhances cellular processes already known to sustain the CML pathogenesis. Overall design: According to conventional and molecular cytogenetics (FISH) data, 12 CML cases with classic t(9;22) and of 8 cases with variant translocations were selected and analyzed by GEP.