The presence of mature granulocytes/monocytes derived from leukemic cells in MLL-associated leukemia.
We observed the mature granulocytes/monocytes derived from leukemic cells in patients with acute myeloid leukemia who present mixed lineage leukemia gene (MLL). Morphologic observation and fluorescence in situ hybridization analysis (FISH) for chromosome 11q23 abnormality were studied, and a multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analysis was done to identify the fusion partners with MLL. The bone marrow cells with FISH signals of MLL showed the cell differentiation of the myeloid and/or monocytic lineages in 4 of 6 AML patients. MLL partner genes were AF6, AF9, ELL, and ENL, respectively. There was no correlation between the fusion partner and the appearance of mature cells derived from MLL clones. RT-PCR showed the fusion between MLL exon 9 or 10 and the partner genes in mature granulocytes/monocytes. These findings suggest that subgroup of leukemia cells with MLL rearrangement has the differentiation potential of leukemic cells and mature granulocytes/monocytes derived from MLL clones may be biologically different from normal mature cells.
Kobayashi
Shoichi
S
Division of Clinical Laboratory, Kanagawa Cancer Center, Yokohama, Japan.
Obata
Masato
M
Division of Clinical Laboratory, Kanagawa Cancer Center, Yokohama, Japan.
Hagihara
Maki
M
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan.
Motohashi
Kenji
K
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan.
Ito
Satomi
S
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan.
Ohshima
Rika
R
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan.
Sakai
Rika
R
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan.
Maruta
Atsuo
A
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan.
Kanamori
Heiwa
H
Department of Hematology, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama, 241-0815, Japan. kanamori@kcch.jp.
D000328:Adult; D001854:Bone Marrow Cells / Q000473:pathology; D005260:Female; D006098:Granulocytes / Q000473:pathology; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000235:genetics* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000473:pathology; D051788:Myeloid-Lymphoid Leukemia Protein / Q000235:genetics*
D051788:Myeloid-Lymphoid Leukemia Protein