Protein kinase C activation by anthracyclines in Swiss 3T3 cells

C. Lanzi, R. A. Gambetta, P. Perego, P. Banfi, A. Franzi, L. Guazzoni, F. Zumino

Research output: Contribution to journalArticlepeer-review


The effects of the anti-cancer anthracyclines doxorubicin and daunorubicin on the activity of protein kinase C (PKC) were examined in intact Swiss 3T3 cells. The 2 drugs stimulated the phosphorylation of an 80K phosphoprotein found to be identical to that generated in response to the PKC activator 12-O-tetradecanoylphorbol-13-acetate as indicated by gel electrophoresis and peptide mapping. The effect of doxorubicin was dose-dependent in the range 10-5 to 10-3 M and was not associated with a detectable translocation of PKC activity from cytosol to the cell membrane. Doxorubicin and daunorubicin were found to increase the incorporation of phosphate into phosphatidic acid, phosphatidylinositol 4-monophosphate and phosphatidyl inositol 4,5-bisphosphate. In addition, the anthracyclines induced a rise in inositol phosphates, thus indicating a stimulation of the breakdown of phosphoinositides. These data are consistent with an indirect mechanism of PKC activation by anthracyclines. We propose that diacylglycerol, which is derived from the hydrolysis of phospholipids, (including the phosphoinositides), by activation of phospholipases, could mediate PKC activation. The described effects, involving cell-signal-transducing pathways, emphasize a new aspect of the cellular actions of these anti-tumor agents.

Original languageEnglish
Pages (from-to)136-142
Number of pages7
JournalInternational Journal of Cancer
Issue number1
Publication statusPublished - 1991

ASJC Scopus subject areas

  • Cancer Research
  • Oncology


Dive into the research topics of 'Protein kinase C activation by anthracyclines in Swiss 3T3 cells'. Together they form a unique fingerprint.

Cite this