1: Biochem Biophys Res Commun. 1998 Jun 9;247(1):65-9. 

Transcription factor NF-E2 is essential for the polyploidization of a human
megakaryoblastic cell line, Meg-J.

Kobayashi S, Teramura M, Ito K, Iwabe K, Inaba T, Mizoguchi H.

Department of Hematology, Tokyo Women's Medical College, Japan.

Transcription factors regulating the process of megakaryocyte development remain
largely unclarified. To clarify them further, we used a human megakaryoblastic
cell line, Meg-J, which showed prominant polyploidization and augmented platelet
glycoprotein (GP) Ib expression after incubation with thrombopoietin (TPO, c-mpl
ligand) and K252a (an indolocarbasole derivative). Under these conditions, we
analyzed the expression of the transcription factors and observed that the
expression of NF-E2 p45, but not those of GATA-1, GATA-2, Tal-1/SCL, Evi-1, and
MafK, was increased after TPO and K252a stimulation. Gel-shift assay confirmed
the enhanced binding activity to the NF-E2 site. The abolishment of NF-E2 p45
with NF-E2 antisense oligomers inhibited TPO plus K252a-induced
polyploidization. These findings suggest that NF-E2 p45 is essential for the
polyploidization of megakaryocytic cells.

PMID: 9636655 [PubMed - indexed for MEDLINE]


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2: Blood. 1995 Jun 15;85(12):3713-8. 

Ecotropic virus integration site-1 gene preferentially expressed in
post-myelodysplasia acute myeloid leukemia: possible association with GATA-1,
GATA-2, and stem cell leukemia gene expression.

Ohyashiki JH, Ohyashiki K, Shimamoto T, Kawakubo K, Fujimura T, Nakazawa S,
Toyama K.

First Department of Internal Medicine, Tokyo Medical College, Japan.

We investigated expression of the human ecotropic virus integration site-1
(EVI1) gene in patients with leukemia and myelodysplastic syndrome (MDS) using
the reverse transcriptase-polymerase chain reaction (RT-PCR) method. The EVI1
transcripts were detected in 5 (10.0%) of 50 patients with de novo acute myeloid
leukemia (AML), including two AML patients with trilineage myelodysplasia, and
in 8 (34.8%) of 23 patients with post-myelodysplastic syndrome AML (post-MDS
AML). EVI1 expression was also detected in 6 (35.3%) of 17 MDS patients and
three of six patients with chronic myeloid leukemia (CML) in myelomegakaryoblast
crisis. No EVI1 transcripts were detected in patients with acute lymphoid
leukemia (n = 15) or CML in lymphoid blast crisis (n = 4). Chromosomal
abnormalities at the 3q26 region, where the EVI1 gene is located, were found in
one patient with MDS and two patients with CML myelomegakaryoblast crisis who
had EVI1 expression. Our results showed that EVI1 expression was frequent in
patients with post-MDS AML and AML with trilineage myelodysplasia, regardless of
the presence or absence of 3q26 abnormalities. EVI1 expression was accompanied
by expression of GATA-1 and GATA-2, and often by stem cell leukemia (SCL) gene
expression. In patients with post-MDS AML, EVI1 expression was not always
associated with a 3q26 abnormality, whereas EVI1 expression in CML
myelomegakaryoblast crisis was often linked to a 3q26 abnormality. Our results
suggest that the leukemogenic role of EVI1 expression may differ between
post-MDS AML and leukemia, with EVI1 expression associated with a 3q26
abnormality.

PMID: 7780155 [PubMed - indexed for MEDLINE]


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