Cell Growth & Differentiation, Vol 5, Issue 4 367-372, Copyright © 1994 by American Association of Cancer Research

ARTICLES

Raf-1 is a necessary component of the mitogenic response of the human megakaryoblastic leukemia cell line MO7 to human stem cell factor, granulocyte-macrophage colony-stimulating factor, interleukin 3, and interleukin 9

U Brennscheidt, D Riedel, W Kolch, R Bonifer, MA Brach, A Ahlers, RH Mertelsmann and F Herrmann
Department of Medical Oncology and Applied Molecular Biology, Free University of Berlin, Germany.

We have examined the role of Raf-1 in the mitogenic response of the factor-deprived human megakaryoblastic leukemia cell line MO7 to recombinant human granulocyte-macrophage colony-stimulating factor, interleukin 3, interleukin 9, and stem cell factor by using c-raf antisense oligodeoxyribonucleotides. Uptake of oligodeoxyribonucleotides by MO7 cells was maximal at 5-10 h in culture, and oligomers remained stable in these cells for at least 24 h. Treatment of MO7 cells with the antisense oligomer resulted in intracellular oligomer/mRNA duplex formation followed by efficient translation blockade of c-raf-1. In contrast, sense and non-sense oligodeoxyribonucleotides failed to form intracellular duplexes and did not interfere with translation of c-raf-1, suggesting specific elimination of c-raf-1 by the antisense oligodeoxyribonucleotide. Furthermore, exposure of MO7 cells to c-raf-1 antisense prevented factor-induced nuclear translocation of Raf-1. Most importantly, proliferation of MO7 cells ([3H]thymidine incorporation) enabled by these growth factors was significantly reduced when the c-raf-1 antisense oligodeoxyribonucleotide was added to cultures, whereas the mitogenic response to these factors remained almost unaffected in the presence of sense and non-sense oligodeoxyribonucleotides.

This article has been cited by other articles:

				V. Planchamp, C. Bermel, L. Tonges, T. Ostendorf, S. Kugler, J. C. Reed, P. Kermer, M. Bahr, and P. Lingor BAG1 promotes axonal outgrowth and regeneration in vivo via Raf-1 and reduction of ROCK activity Brain, October 1, 2008; 131(10): 2606 - 2619. [Abstract] [Full Text] [PDF]

				A. A. Adjei and M. Hidalgo Intracellular Signal Transduction Pathway Proteins As Targets for Cancer Therapy J. Clin. Oncol., August 10, 2005; 23(23): 5386 - 5403. [Abstract] [Full Text] [PDF]

				C. C. Cunningham, J. T. Holmlund, J. H. Schiller, R. S. Geary, T. J. Kwoh, A. Dorr, and J. Nemunaitis A Phase I Trial of c-Raf Kinase Antisense Oligonucleotide ISIS 5132 Administered as a Continuous Intravenous Infusion in Patients with Advanced Cancer Clin. Cancer Res., May 1, 2000; 6(5): 1626 - 1631. [Abstract] [Full Text]

				K. W. Muszynski, F. W. Ruscetti, J. M. Gooya, D. M. Linnekin, and J. R. Keller Raf-1 Protein is Required for Growth Factor-Induced Proliferation of Primitive Hematopoietic Progenitors Stimulated with Synergistic Combinations of Cytokines Stem Cells, January 1, 1997; 15(1): 63 - 72. [Abstract] [Full Text]