Rapid expression of protooncogenes c-fos and c-myc in B-chronic lymphocytic leukemia cells during differentiation induced by phorbol ester and calcium ionophore

H. G. Drexler, J. W.G. Janssen, M. K. Brenner, A. V. Hoffbrand, C. R. Bartram

Research output: Contribution to journalArticle

16 Scopus citations

Abstract

The peripheral blood mononuclear cells from patients with B-chronic lymphocytic leukemia (B-CLL) were incubated for 0.5 h to 72 h in the presence of the phorbol ester TPA, the calcium ionophore A23187, or a combination of these reagents. Using Northern blot analysis, total cellular RNA was prepared from cells harvested at different time points and hybridized with DNA clones specific for the protooncogene c-fos and c-myc. While untreated control cells lacked detectable amounts of messenger RNA (mRNA), increase in the level of c-fos mRNA was noted as early as 0.5 h after exposure to the inducers. Peaks of c-fos and c-myc transcript accumulation were seen at 1 h and 4 h after induction, respectively. The most effective inducer was double stimulation with TPA plus A23187. The kinetics of c-fos and c-myc mRNA accumulation in B-CLL appear to be similar to those reported for normal lymphocytes that have been either activated by physiologic external stimuli or by direct activators of protein kinase C and calcium flux (such as TPA and A23187). No direct link between oncogene expression and proliferation or differentiation parameters could be established. These results document that expression of c-fos and c-myc genes, which are among the earliest events following stimulation of the protein kinase signal transduction pathway, can be successfully induced in B-CLL cells. The data provide further evidence for the hypothesis that signal transmission downstream of protein kinase C is intact in B-CLL.

Original languageEnglish (US)
Pages (from-to)1656-1663
Number of pages8
JournalBlood
Volume73
Issue number6
DOIs
StatePublished - 1989

ASJC Scopus subject areas

  • Biochemistry
  • Immunology
  • Hematology
  • Cell Biology

Fingerprint Dive into the research topics of 'Rapid expression of protooncogenes c-fos and c-myc in B-chronic lymphocytic leukemia cells during differentiation induced by phorbol ester and calcium ionophore'. Together they form a unique fingerprint.

Cite this