Differences in BCL-X(L) expression and STAT5 phosphorylation in chronic myeloid leukaemia patients.

Chronic myelogenous leukaemia (CML) cells show expression of BCL-X(L), an anti-apoptotic oncogene. This expression is induced by BCR-ABL protein kinase through activation of the signal transducer and activator of transcription-5 protein (STAT5). To date, however, the contribution of BCL-X(L) and STAT5 to the transforming phenotype in CML is still unclear.