Chromosome characteristics of therapy-related acute non-lymphocytic leukemia and preleukemia: possible implications for pathogenesis of the disease.

Most cases of therapy-related acute nonlymphocytic leukemia or preleukemia show chromosome aberrations, primarily loss of whole chromosomes No. 5 and/or No. 7 or the long arms of these two chromosomes. Other abnormalities involve chromosome No. 21, often rearranged at band 21q22, and chromosome No. 17, in some cases rearranged at band 17p13. Important cellular genes have recently been localized to these regions, including the gene for one hematopoietic growth factor and the gene for the receptor for another hematopoietic growth factor. It is suggested that the total loss or change of structure or expression of some of these genes resulting from the various chromosome aberrations may be of pathogenetic significance in therapy-related acute nonlymphocytic leukemia.