BIRC3 alterations in chronic and B-cell acute lymphocytic leukemia patients.

Deletions within chromosome 11q22-23, are considered among the most common chromosomal aberrations in chronic lymphocytic leukemia (CLL), and are associated with a poor outcome. In addition to the ataxia telangiectasia mutated () gene, the baculoviral IAP repeat-containing 3 () gene is also located in the region. encodes a negative regulator of the non-canonical nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) protein. Disruption of is known to be restricted to CLL fludarabine-refractory patients. The aim of the present study was to determine the frequency of copy number changes of and to assess its association with two known predictors of negative CLL outcome, and tumor protein 53 () gene deletions. To evaluate the specificity of alterations to CLL, copy numbers were assessed in 117 CLL patients in addition to 45 B-cell acute lymphocytic leukemia (B-ALL) patients. A commercially available multiplex ligation dependent probe amplification kit, which includes four probes for the detection of and four probes for gene region, was applied. Interphase-directed fluorescence hybridization was used to apply commercially available probes for , and . High resolution array-comparative genomic hybridization was conducted in selected cases. Genetic abnormalities of were detected in 23/117 (~20%) of CLL and 2/45 (~4%) of B-ALL cases. Overall, 20 patients with CLL and 1 with B-ALL possessed a deletion, whilst 3 patients with CLL and 1 with B-ALL harbored a duplication. All patients with an deletion also carried a deletion. Only 2 CLL cases possessed deletions in , and simultaneously. Evidently, the deletion or duplication of may be observed rarely in B-ALL patients. duplication may occur in CLL patients, for which the prognosis requires additional studies in the future. The likelihood that deletions occur simultaneously with and/or aberrations is low. However, as deletions may, but not always, associate with deletions, each region should be considered in the future diagnostics of CLL in order to aid treatment decisions, notably whether to treat with or without fludarabine.