Activation of PKC is required for arsenite-induced signal transduction

J Environ Pathol Toxicol Oncol. 2000;19(3):297-305.

Abstract

Trivalent arsenic (arsenite) is a human carcinogen. However, the molecular mechanism of arsenite-induced carcinogenesis is still not well understood. In this study, we found that arsenite induced translocation of PKCepsilon, PKCdelta, and PKCalpha from cytosol to membranes. Rottlerin, a selective inhibitor for PKCdelta, and safingol, a specific inhibitor for PKCalpha, both markedly inhibited arsenite-induced AP-1 activity. These inhibitory effects by rottlerin and safingol appeared to be dose dependent. Arsenite-induced phosphorylation of Erks was inhibited by rottlerin, while safingol inhibited arsenite-induced phosphorylation of JNKs and p38 kinases. Dominant negative mutant transfectant of PKCepsilon markedly blocked arsenite-induced AP-1 activity and the phosphorylation of Erks, JNKs, and p38 kinases. These data demonstrate that PKCdelta, PKCepsilon, and PKCalpha mediate arsenite-induced AP-1 activation in JB6 cells through different MAP kinase (Erks, JNKs, and p38 kinases) pathways.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acetophenones / pharmacology
  • Animals
  • Arsenites / antagonists & inhibitors
  • Arsenites / toxicity*
  • Benzopyrans / pharmacology
  • Carcinogens / toxicity*
  • Cell Membrane / enzymology
  • Cells, Cultured
  • Cytosol / enzymology
  • Enzyme Activation
  • Enzyme Activators / toxicity*
  • Enzyme Inhibitors / pharmacology
  • Isoenzymes / antagonists & inhibitors
  • Isoenzymes / genetics
  • Isoenzymes / metabolism
  • JNK Mitogen-Activated Protein Kinases
  • MAP Kinase Signaling System / drug effects*
  • MAP Kinase Signaling System / physiology
  • Mice
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • Mitogen-Activated Protein Kinases / metabolism
  • Mutation
  • Protein Kinase C / antagonists & inhibitors
  • Protein Kinase C / genetics
  • Protein Kinase C / metabolism*
  • Protein Kinase C-alpha
  • Protein Kinase C-delta
  • Protein Kinase C-epsilon
  • Skin / cytology
  • Skin / drug effects
  • Skin / metabolism
  • Sphingosine / analogs & derivatives
  • Sphingosine / pharmacology
  • Transcription Factor AP-1 / biosynthesis
  • Transcription Factor AP-1 / metabolism
  • Transfection
  • p38 Mitogen-Activated Protein Kinases

Substances

  • Acetophenones
  • Arsenites
  • Benzopyrans
  • Carcinogens
  • Enzyme Activators
  • Enzyme Inhibitors
  • Isoenzymes
  • Transcription Factor AP-1
  • rottlerin
  • Prkcd protein, mouse
  • Prkce protein, mouse
  • Prkca protein, mouse
  • Protein Kinase C
  • Protein Kinase C-alpha
  • Protein Kinase C-delta
  • Protein Kinase C-epsilon
  • JNK Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • arsenite
  • Sphingosine
  • safingol