Conversion of a stem cell leukemia from a T-lymphoid to a myeloid phenotype induced by the adenosine deaminase inhibitor 2'-deoxycoformycin.
AUTOR(ES)
Hershfield, M S
RESUMO
Selective failure of lymphoid development occurs in genetic deficiency of adenosine deaminase (ADA). We examined the in vivo effects of a potent inhibitor of ADA, 2'-deoxycoformycin, which was used to treat a patient with refractory acute leukemia. Unexpectedly, within 7 days of starting treatment, the leukemic phenotype underwent complete conversion from T lymphoblastic to promyelocytic, with kinetics that suggested a precursor-product relationship between the two cell populations. Pretreatment T lymphoblasts and posttreatment promyelocytes had the same abnormal karyotype. Upon culture in vitro, the former transformed spontaneously over several weeks into mature myeloid cells. We conclude that the leukemia arose from a multipotent stem cell capable of both lymphoid and myeloid differentiation. Effects of ADA inhibition on leukemia cells during treatment included expansion of the deoxyadenosine nucleotide pool and accumulation of S-adenosylhomocysteine, a potent inhibitor of S-adenosylmethionine-dependent methylation. The influence of these changes on the leukemic phenotype is discussed in terms of (i) selective cytotoxicity to T lymphoblasts, which accumulated deoxyadenosine nucleotides more efficiently than did the patient's promyelocytes during in vitro incubation with deoxycoformycin plus deoxyadenosine, and (ii) induction of an altered program of differentiation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=344650Documentos Relacionados
- Transformation of T-lymphoid cells by Abelson murine leukemia virus.
- Reticuloendotheliosis virus REV-T(REV-A)-induced neoplasia: development of tumors within the T-lymphoid and myeloid lineages.
- Differentiation of human T-lymphoid leukemia cells into cells that have a suppressor phenotype is induced by phorbol 12-myristate 13-acetate.
- E2a/Pbx1 Induces the Rapid Proliferation of Stem Cell Factor-Dependent Murine Pro-T Cells That Cause Acute T-Lymphoid or Myeloid Leukemias in Mice
- BCL2-mediated tumorigenicity of a human T-lymphoid cell line: synergy with MYC and inhibition by BCL2 antisense.