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Andrew Lister

Publications and source records attributed to Andrew Lister.

3 recordsLinked to original sources

The leukemic fusion gene AML1-MDS1-EVI1 suppresses CEBPA in acute myeloid leukemia by activation of Calreticulin.

The leukemic fusion gene AML1-MDS1-EVI1 (AME) encodes a chimeric transcription factor that results from the t(3,21)(q26;q22) translocation seen in patients with acute myeloid leukemia, with therapy-related myelodysplastic syndrome, or with chronic myeloid leukemia in blast crisis. The myeloid transcription factor CEBPA is crucial for normal granulopoiesis. Here, we found that conditional expression of AME suppresses CEBPA protein by 90.8% and DNA-binding activity by 93.9%. In contrast, CEBPA mRNA levels remained unchanged. In addition, we detected no differences in CEBPA mRNA levels in leukemic blasts of patients carrying the AME translocation (n = 8) compared to acute myeloid leukemia patients with a normal karyotype (n = 9). CEBPA protein and binding activity, however, were reduced significantly (100% and 92.1%, respectively) in AME patient samples. Furthermore, we observed that calreticulin (CRT), a putative inhibitor of CEBPA translation, was strongly activated after induction of AME in the cell-line system (14.8-fold) and in AME patient samples (12.2-fold). Moreover, inhibition of CRT by small interfering RNA powerfully restored CEBPA levels. These results identify CEBPA as a key target of the leukemic fusion protein AME and suggest that modulation of CEBPA by CRT may represent a mechanism involved in the differentiation block in AME leukemias.

Adult↗

Comparative genomic hybridization and multiplex-fluorescence in situ hybridization: an appraisal in elderly patients with acute myelogenous leukemia.

Comparative genomic hybridization (CGH) and multiplex-fluorescence in situ hybridization (M-FISH) were used to evaluate the presentation karyotype in 15 and 18 patients respectively, aged >/=60 years, with acute myeloid leukemia (AML). Conventional G-banded analysis was performed in all patients prior to evaluation. Comparative genomic hybridization confirmed the G-banded karyotype fully in 12 patients and partially in two patients. Normal CGH profiles were observed in patients with a normal karyotype and in one patient with a balanced chromosomal translocation as the sole cytogenetic aberration. Multiplex-fluorescence in situ hybridization provided additional information in two patients with a complex karyotype, but failed to detect a telomeric translocation in one patient. Eight patients with normal G-banded karyotypes appeared normal by M-FISH. These results demonstrate that both CGH and M-FISH analysis correlate well with the G-banded karyotype in AML. Furthermore, although additive cytogenetic data was not provided by either technique in cases with normal karyotype, DNA copy number change and cryptic translocations below the resolution of CGH and M-FISH may still be the initiating event for leukemogenesis for these patients.

Aged↗

Central nervous system lymphoma.

Central nervous system involvement with malignant lymphoma whether primary or secondary is an uncommon but not rare complication observed in the management of patients with hematological malignancy. Its importance lies in the considerable morbidity and mortality with which it is associated and the inadequacy of therapy. In Section I, Dr. Lauren Abrey addresses the totality of the problem of primary central nervous system lymphoma, with emphasis on strategies increasingly dependent on systemic chemotherapy. In Section II, Dr. John Sandlund reviews the success of sequential clinical trials of overall therapy for acute lymphoblastic leukemia in childhood, identifying those patients at high risk of central nervous system leukemia and the development of a rational therapeutic strategy for prevention. In Section III, Dr. Andrew Lister discusses the issue of secondary central nervous system involvement with lymphoma and the indications for prophylaxis.

Antineoplastic Agents↗