Activation of a novel calcineurin-mediated insulin-like growth factor-1 receptor pathway, altered metabolism, and tumor cell invasion in cells subjected to mitochondrial respiratory stress

J Biol Chem. 2007 May 11;282(19):14536-46. doi: 10.1074/jbc.M611693200. Epub 2007 Mar 13.

Abstract

We have previously shown that disruption of mitochondrial membrane potential by depletion of mitochondrial DNA (mtDNA) or treatment with a mitochondrial ionophore, carbonyl cyanide m-chlorophenylhydrazone, initiates a stress signaling, which causes resistance to apoptosis, and induces invasive behavior in C2C12 myocytes and A549 cells. In the present study we show that calcineurin (Cn), activated as part of this stress signaling, plays an important role in increased glucose uptake and glycolysis. Here we report that, although both insulin and insulin-like growth factor-1 receptor levels (IR and IGF1R, respectively) are increased in response to mitochondrial stress, autophosphorylation of IGF1R was selectively increased suggesting a shift in receptor pathways. Using an approach with FK506, an inhibitor of Cn, and mRNA silencing by small interference RNA we show that mitochondrial stress-activated Cn is critical for increased GLUT 4 and IGF1R expression and activation. The importance of the IGF1R pathway in cell survival under mitochondrial stress is demonstrated by increased apoptosis either by IGF1R mRNA silencing or by treatment with IGF1R inhibitors (AG1024 and picropodophyllin). This study describes a novel mechanism of mitochondrial stress-induced metabolic shift involving Cn with implications in resistance to apoptosis and tumor proliferation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Apoptosis
  • Calcineurin / genetics
  • Calcineurin / metabolism*
  • Calcium Signaling
  • Cell Membrane / metabolism
  • Cell Respiration / physiology*
  • Cells, Cultured
  • Deoxyglucose / metabolism
  • Glucose Transporter Type 4 / metabolism
  • Humans
  • Immunoblotting
  • Immunoprecipitation
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology
  • Mice
  • Mitochondria / metabolism*
  • Myoblasts, Skeletal / cytology
  • Myoblasts, Skeletal / drug effects
  • Myoblasts, Skeletal / metabolism
  • Myocytes, Cardiac / cytology
  • Myocytes, Cardiac / drug effects
  • Myocytes, Cardiac / metabolism
  • Neoplasm Invasiveness / pathology*
  • Oxidative Stress*
  • Phosphorylation / drug effects
  • RNA, Messenger / antagonists & inhibitors
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / pharmacology
  • Rats
  • Receptor, IGF Type 1 / antagonists & inhibitors
  • Receptor, IGF Type 1 / genetics
  • Receptor, IGF Type 1 / metabolism*
  • Receptor, Insulin / antagonists & inhibitors
  • Receptor, Insulin / genetics
  • Receptor, Insulin / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction*
  • Transfection

Substances

  • Glucose Transporter Type 4
  • RNA, Messenger
  • RNA, Small Interfering
  • Adenosine Triphosphate
  • Deoxyglucose
  • Receptor, IGF Type 1
  • Receptor, Insulin
  • Calcineurin

Associated data

  • PDB/2ODC