COMPARATIVE GENOMIC HYBRIDIZATION REVEALS PREVIOUSLY UNDESCRIBED AMPLIFICATIONS AND DELETIONS IN THE CHRONIC MYELOID LEUKEMIA-DERIVED K-562CELL-LINE

We used comparative genomic hybridization (CGH) to identify a number o f previously undescribed chromosomal imbalances in K-562, a spontaneou sly transformed cell line originally derived from leukemic cells of a chronic myeloid leukemia (CML) patient in blast crisis. Noteworthy wer e a discrete amplification in band 13q31, increased copy number of chr omosome arms 1q, 5p, 6p, and 16q, and loss of material from 8p, 9p, 10 q, and 17p. Amplification within bands 9q34 and 22q11.2 was consistent with previous descriptions of increased copy number of the CML-specif ic 5'BCR-3'ABL fusion gene in K-562. However, amplification of a large distal segment, 9q31-->9q34, mostly proximal to the ABL locus, was un expected and is unlikely to be related to BCR-ABL recombination. Previ ous karyotype studies are reviewed in detail and compared with the CGH findings. (C) 1997 Wiley-Liss, Inc.