Phorbol ester-induced terminal differentiation is inhibited in human U-937 monoblastic cells expressing a v-myc oncogene.
Induction of differentiation of the human monoblastic cell line U-937 in vitro by several physiologic and nonphysiologic inducers is accompanied by a rapid decrease in expression of MYC, the endogenous human myc protooncogene. To investigate whether this reduction is a prerequisite for terminal differentiation, we introduced a constitutively expressed v-myc gene into U-937 cells. The results show that constitutive expression of an avian v-myc oncogene does not interfere with phorbol 12-myristate 13-acetate-induced differentiation of U-937 cells early after stimulation. However, after 24 hr the differentiation process is reversed, as judged by a full recovery of the proliferative capacity and reexpression of the immature phenotype, within the next 2-4 days. We conclude that the terminal stage of macrophage differentiation is inhibited in U-937 cells constitutively expressing a v-myc oncogene.
Larsson
L G
LG
Department of Pathology, University of Uppsala, University Hospital, Sweden.
Ivhed
I
I
Gidlund
M
M
Pettersson
U
U
Vennström
B
B
Nilsson
K
K
D000920:Antibody-Dependent Cell Cytotoxicity; D002448:Cell Adhesion; D002454:Cell Differentiation / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D005786:Gene Expression Regulation; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D009000:Monocytes / Q000166:cytology* / Q000276:immunology; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D009857:Oncogenes; D012333:RNA, Messenger / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D009856:Oncogene Proteins, Viral; D012333:RNA, Messenger; D013755:Tetradecanoylphorbol Acetate