Bcl-2 gene expression in hematopoietic cell differentiation

Istituto di Clinica Medica II, Università di Modena, Italy.
Blood (Impact Factor: 10.45). 09/1992; 80(3):768-75.
Source: PubMed


Nonrandom translocations with breakpoint at band q21 on chromosome 18 might cause bcl-2 gene deregulation and might contribute to neoplastic transformation in human lymphomas. As the pattern of expression of bcl-2 in hematopoietic cells is still unclear, we have measured the level of the corresponding messenger RNA (mRNA) in a variety of myeloid and lymphoid cell malignancies not usually associated with the t(14;18) translocation. Molecular genetic analysis showed that bcl-2 was rearranged in only 2 of 77 patients: one was affected by hairy cell leukemia and one by diffuse small cleaved cell lymphoma with peripheral blood invasion. Although in rare cases of myeloid leukemia fairly high levels can be found, the expression of bcl-2 appears to be typical of certain lymphoid malignancies. High levels of bcl-2 mRNA had been found, previously, in established pre-B-cell lines. However, in fresh specimens, the peak level of bcl-2 expression shifts to a more differentiated cell type, represented by the long-living B lymphocytes that are found in most cases of chronic lymphocytic leukemia. bcl-2 gene product might have a role in prolonging cell survival and, even in the absence of translocations, might contribute to some of the biologic features that are typical of this disorder.

Full-text preview

Available from:
  • Source
    • "Using a system whereby fetal liver-derived hematopoietic progenitor cells (HPCs) are induced to differentiate into B lineage cells, this group show that stable overexpression of a dominant negative PKC (PKC-KR) leads to the generation of a population of malignant cells bearing a CLL phenotype (CD19 hi , CD23 + , CD5 + , sIgM lo ) (Figure 4C). This population of malignant cells, like human CLL cells, are arrested in G 0 /G 1 phase of the cell cycle and have enhanced expression of Bcl-2 (Hanada, et al., 1993;Kitada, et al., 1998;Mariano, et al., 1992). However, when these cells are injected into SCID mice they have an enhanced proliferative capacity over mock-transfected and non-transfected control populations. "

    Chronic Lymphocytic Leukemia, 02/2012; , ISBN: 978-953-307-881-6

  • Leukemia and Lymphoma 02/1993; 11 Suppl 2(s2):71-4. DOI:10.3109/10428199309064265 · 2.89 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We found no rearrangements in the 5' region of the BCL2 gene in DNA samples from 60 patients with chronic B-cell leukemia (CLL). This compares with the presence of these rearrangements in up to 10% of patients in other reports, and suggests that the incidence of 5' BCL2 rearrangements in CLL is considerably less than 10%.
    Cancer Genetics and Cytogenetics 09/1993; 69(1):72-3. DOI:10.1016/0165-4608(93)90118-6 · 1.93 Impact Factor
Show more