Sirt2 suppresses glioma cell growth through targeting NF-κB-miR-21 axis

Ya'nan Li1, Dongwei Dai, Qiong Lu

  • 1Department of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai, China.

Insights

Sirtuin 2 (Sir2) is underexpressed in glioma. Overexpressing Sir2 inhibits glioma cell growth and induces apoptosis by suppressing miR-21 via the NF-κB pathway, suggesting Sir2 activators as potential glioma therapeutics.

Area of Science:

  • Molecular Biology
  • Oncology
  • Cellular Biology

Background:

  • Sirtuins (NAD(+)-dependent deacetylases) are involved in various cellular processes, including aging and cancer.
  • The specific roles of sirtuins, particularly Sirtuin 2 (Sir2), in glioma pathogenesis are not well understood.

Purpose of the Study:

  • To investigate the role of Sirtuin 2 (Sir2) in human glioma.
  • To elucidate the molecular mechanisms underlying Sir2's function in glioma, focusing on its interaction with microRNA-21 (miR-21).

Main Methods:

  • Analysis of Sir2 expression in human glioma tissues and cell lines.
  • Overexpression and knockdown studies of Sir2 in glioma cells.
  • Assessment of cell proliferation, colony formation, and apoptosis.
  • Investigation of miR-21 expression levels and its regulation by Sir2.
  • Mechanistic studies involving p65 acetylation and its effect on miR-21 transcription.

Main Results:

  • Sir2 was found to be underexpressed in human glioma tissues and cell lines.
  • Overexpression of Sir2 suppressed glioma cell proliferation and colony formation, while inducing apoptosis.
  • Sir2 overexpression inhibited miR-21 expression, and this inhibition was crucial for Sir2's anti-glioma effects.
  • Mechanistically, Sir2 deacetylated p65 at K310, preventing p65 binding to the miR-21 promoter and thus repressing miR-21 transcription.

Conclusions:

  • Sirtuin 2 plays a critical tumor-suppressive role in human glioma through the NF-κB-miR-21 pathway.
  • Sirt2 activators represent a promising therapeutic strategy for glioma treatment.

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