International Journal of Cell Cloning, Vol 10, 47-53, Copyright © 1992 by AlphaMed Press
A phorbol diester resistant monocytic leukemia cell line is PKC deficient
NA Ansari and MC Wu
Division of Biochemistry, University of North Texas/Texas College of Osteopathic Medicine, Denton 76203.
MIA C51 is a rat monocytic leukemia cell line which exhibits
undifferentiated monocytic phenotype in culture. The proliferation of MIA
C51 cells was not inhibited by the addition of 12-O-tetradecanoyl-
phorbol-13-acetate (TPA, 1 microgram/ml) or phorbol 12, 13 dibutyrate
(PDBu, 10 micrograms/ml). Comparison of MIA C51 cells to a phorbol
diester-sensitive human monoblastoid U-937 cell line demonstrated that MIA
C51 cells contained significantly lower number of PDBu receptors, protein
kinase C (PKC) activity, and PKC protein level. Further experiments
demonstrated that addition of TPA to MIA C51 cells did not induce the
expression of c-fos proto-oncogene; whereas incubation of MIA C51 cells
with N6, O2-dibutyryl cyclic adenosine 3',5' monophosphate (Bt2cAMP)
resulted in a rapid increase of c-fos mRNA level. Thus, this cell line
provides a new system for studying the signal transduction mechanisms in
induced monocytic differentiation.
