1/2. Translocation (4;15)(p16;q24): a novel reciprocal translocation in a patient with BCR/ABL negative myeloproliferative syndrome progressing to blastic phase.A patient with BCR/ABL negative myeloproliferative syndrome with a 46,XY,del(3)(q21), t(4;15)(p16;q24) karyotype is described. fluorescence in situ hybridization performed with chromosomes 4 and 15 painting probes confirmed a novel reciprocal (4;15) translocation. The absence of crkl tyrosine phosphorylation, no activation of the abl kinase as measured by autophosphorylation, and a normal-size abl transcript suggest an alternative mechanism for leukemogenesis to that operative in Ph positive BCR/ABL positive chronic myeloid leukemia. A number of genes potentially relevant to tumorigenesis, some involving the ras signaling pathway, map to the 4p16 and 15q24 chromosome regions.- - - - - - - - - - ranking = 1keywords = leukemia (Clic here for more details about this article) |
2/2. Effects of sCD23 on proliferation of leukemic cells from a patient with chronic myelogenous leukemia during blast crisis.The present study has attempted to further delineate the growth factor requirements of peripheral blasts of a patient with CML in acute phase. Phenotypic analysis of leukemic blasts from this patient before culture has shown a homogenous population of CD34 cells at the onset of blast crisis. In the second and third samples the percentage of CD34 DR blast cells decreased slightly and up to 32% of cells in the third sample expressed the CD19 antigen. Optimal proliferation of cells derived from the first sample required the presence of exogenous sCD23 and to a lesser extent IL7. The stimulatory effects of sCD23 and IL7 were clearly reduced 4 months later and no longer detected after 6 months. This variability in growth factor response along with disease progression may be related to phenotypic differentiation. There was no evidence for lymphoid or myeloid maturation after 4 days of liquid culture. Our results in conjunction with previous studies are in agreement with sCD23-involvement in the complex control of proliferative processes at both normal and leukemic stages, demonstrating that cytokines are critical in determining CML cell proliferation.- - - - - - - - - - ranking = 4keywords = leukemia (Clic here for more details about this article) |