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Updated: Jul 15, 2026

Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
08:07

Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma

Published on: April 12, 2019

Sensitization of osteosarcoma cells to apoptosis by oncostatin M depends on STAT5 and p53

C Chipoy1, B Brounais, V Trichet

  • 1INSERM, ERI 7, Nantes, France. celine.chipoy@univ-nantes.fr

Oncogene
|May 2, 2007
PubMed

Insights

Oncostatin M (OSM) promotes osteoblast apoptosis via the mitochondrial pathway, involving p53 and STAT5 activation. This finding suggests new therapeutic strategies for osteosarcoma.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Oncology

Background:

  • Oncostatin M (OSM), an interleukin-6 family cytokine, is known to induce growth arrest and differentiation in osteoblasts.
  • The role of OSM in regulating apoptosis of normal and transformed osteoblasts remains largely unexplored.

Purpose of the Study:

  • To investigate the effect of OSM on osteoblast apoptosis.
  • To elucidate the molecular mechanisms underlying OSM-induced apoptosis in osteoblasts.

Main Methods:

  • Apoptosis assays were performed using various death inducers (staurosporine, UV, TNF-alpha).
  • Mitochondrial pathway involvement was assessed by cytochrome c release and caspase activation.
  • DNA microarrays were used to analyze gene expression changes.
  • Pharmacological inhibitors, dominant-negative STATs, RNA interference, and knockout cells were employed to study transcription factor roles.

Main Results:

  • OSM sensitizes both normal and osteosarcoma cells to apoptosis induced by multiple death stimuli.
  • Apoptosis is mediated by the mitochondrial pathway, involving cytochrome c release and caspase-9/-3 activation.
  • OSM modulates the expression of key apoptosis-related genes, including Bax, Bad, Bnip3, Bcl-2, and Mcl-1.
  • OSM-activated transcription factors p53 and STAT5 are crucial for apoptosis sensitization, mediating Bax induction and Bcl-2 reduction, respectively.

Conclusions:

  • OSM sensitizes osteoblasts to apoptosis through mitochondrial pathway activation, involving p53 and STAT5.
  • The increased Bax/Bcl-2 ratio is a key mechanism in OSM-induced apoptosis.
  • Combining OSM with kinase inhibitors like Sts offers potential therapeutic strategies for p53 wild-type osteosarcoma.

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