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Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer
08:34

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Published on: April 13, 2015

Activin inhibits telomerase activity in cancer

Indzi Katik1, Charley Mackenzie-Kludas, Craig Nicholls

  • 1Department of Immunology, Monash University, Central Clinical School, Commercial Road, Melbourne, Vic. 3004, Australia.

Biochemical and Biophysical Research Communications
|September 23, 2009
PubMed

Insights

Activin-A inhibits cancer cell proliferation by suppressing telomerase activity. This involves down-regulating the human telomerase reverse transcriptase (hTERT) gene expression, offering a potential new therapeutic strategy.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Cancer Research

Background:

  • Activin is a cytokine with diverse tissue distribution.
  • Activin-A is known to inhibit cancer cell proliferation through mechanisms not fully understood.

Purpose of the Study:

  • To investigate the mechanism by which activin-A inhibits cancer cell proliferation.
  • To determine if activin-A affects telomerase activity and expression in cancer cells.

Main Methods:

  • Treatment of breast and cervical cancer cells with recombinant activin-A.
  • Assay of telomerase activity.
  • Quantitative analysis of human telomerase reverse transcriptase (hTERT) gene expression.
  • Measurement of Smad3 signaling and hTERT gene promoter activity.

Main Results:

  • Recombinant activin-A inhibited telomerase activity in a concentration-dependent manner.
  • Activin-A repressed hTERT gene expression by 60-80% within 24 hours.
  • Activin-A increased Smad3 signaling and decreased hTERT gene promoter activity.

Conclusions:

  • Activin-A-induced telomerase inhibition is mediated by down-regulation of hTERT gene expression.
  • This mechanism contributes to activin-A's anti-proliferative effects on cancer cells.

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