Does multisomy of chromosome 1q confer a proliferative advantage in B-cell acute lymphoblastic leukemia?

Two patients fulfilled the clinical and hematologic criteria for B-cell acute lymphoblastic leukemia: the malignant cells had L3 morphology, bore B-cell markers, and carried the specific t(8;14) translocation. The leukemic cells of one patient were tetrasomic for 1q, and those of the other patient showed several separate cell lines with complete or partial trisomy of 1q. In the latter patient it appeared that a break close to the heterochromatin of 1q produced an unstable chromosome end which formed associations with the telomeres of at least seven other chromosomes. It is suggested that multisomy of 1q gives tumor cells a proliferative advantage and is secondary to the basic neoplastic event.