IDENTIFICATION OF SEVERAL GENES DIFFERENTIALLY EXPRESSED DURING PROGRESSION OF CHRONIC MYELOGENOUS LEUKEMIA

The Bcr-Abr fusion protein plays a crucial role in the initiation and maintenance of chronic myelogenous leukemia (CML). However, additional events are necessary far the transition from the chronic phase to the terminal phase of the disease. To identify genes involved in the dise ase progression, we constructed a subtractive library from enriched K5 62 cell mRNA. We obtained 1084 cDMA clones. After a specific hybridiza tion of these clones with a cDMA probe from either chronic phase or K5 62 cells, 43 clones which present a differential hybridization level h ave been selected. Among them, several clones corresponded to ribosoma l protein genes showing an increased transcription level during the bl ast crisis. We observed variations in the expression of a cellular adh esion molecule, a laminin-binding protein. an increased transcription level of the MAZ gene has been shown in the terminal phase of the dise ase. This gene encodes a protein that regulates the transcription of m yc.