Expression of exogenous NF-IL6 induces apoptosis in Sp2/0-Ag14 myeloma cells.
NF-IL6 (or C/EBP beta) is a multifunctional transcription factor of the C/EBP family. To study the effects of exogenous expression of NF-IL6 on the growth of cells of hematopoietic tumors, we infected SP2/0-Ag14 myeloma cells with pLXSN recombinant retrovirus harboring the NF-IL6 cDNA. We found that the transfected cells revealed changes typical of the apoptosis and finally died. The expression of NF-IL6 protein was shown by a "supershift" assay in the NF-IL6-transfected cells. In controls, where cells were infected by the retroviral vector with a mutant NF-IL6 coding region as well as the vector without insert, no sign for expression of NF-IL6 and apoptosis was observed. Therefore, our work shows that the apoptosis of this myeloma cell line was induced by the exogenous NF-IL6 expression. This is significantly different from the apparent effects of NF-IL6 in leukemia cells and in fibroblasts. These facts indicate that NF-IL6 exerts different functions in different cell types. We discuss possible mechanisms for the NF-IL6-induced apoptosis.
Zhu
M S
MS
Shanghai Institute of Biochemistry, Academia Sinica, People's Republic of China.
Liu
D G
DG
Cheng
H Q
HQ
Xu
X Y
XY
Li
Z P
ZP
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D022762:CCAAT-Enhancer-Binding Proteins; D002455:Cell Division; D002467:Cell Nucleus / Q000473:pathology; D004273:DNA, Neoplasm / Q000032:analysis; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D015870:Gene Expression; D005822:Genetic Vectors / Q000235:genetics; D051379:Mice; D009101:Multiple Myeloma / Q000378:metabolism / Q000473:pathology*; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D012190:Retroviridae / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014407:Tumor Cells, Cultured
D022762:CCAAT-Enhancer-Binding Proteins; D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors