Expression of a novel 3.5-kb macrophage colony-stimulating factor transcript in human myeloma cells.
Macrophage CSF (M-CSF) induces proliferation of monocyte/macrophage progenitor cells and can also activate some functions of mature cells. Three different human M-CSF cDNA (4.0, 3 to 3.5, and 1.5 kb) which are the result of alternative splicing of the single M-CSF gene have been cloned. Each of these cDNA encode a biologically active M-CSF. M-CSF transcripts are expressed in normal fibroblasts and other mesenchymal cells, and also in some hematopoietic cells such as monocytes. Normal human cells examined to date express only the 4.0-kb transcript. In contrast, a 3.5-kb M-CSF transcript was continuously expressed in two multiple myeloma cell lines (RPMI 8226 and U266/AF10) and in a bone marrow specimen of a patient with multiple myeloma. The myeloma cell lines secreted biologically active M-CSF. Resting and activated normal B lymphocytes and other B cell neoplasms examined did not express the 3.5-kb transcript, but could be induced to express the 4.0-kb transcript and to secrete M-CSF. Myeloma cells appear to be unique among hematopoietic cells in their expression of the 3.5-kb M-CSF transcript.
Nakamura
M
M
Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, MA 02115.
Merchav
S
S
Carter
A
A
Ernst
T J
TJ
Demetri
G D
GD
Furukawa
Y
Y
Anderson
K
K
Freedman
A S
AS
Griffin
J D
JD
D001402:B-Lymphocytes / Q000032:analysis; D001483:Base Sequence; D001853:Bone Marrow / Q000032:analysis; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000096:biosynthesis / Q000235:genetics*; D004273:DNA, Neoplasm / Q000032:analysis; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D016173:Macrophage Colony-Stimulating Factor; D009101:Multiple Myeloma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D012334:RNA, Neoplasm / Q000302:isolation & purification; D014158:Transcription, Genetic
D003115:Colony-Stimulating Factors; D004273:DNA, Neoplasm; D012334:RNA, Neoplasm; D016173:Macrophage Colony-Stimulating Factor