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Updated: Jul 17, 2026
08:07
Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
Published on: April 12, 2019
Modulation of apoptotic signalling by 9-hydroxystearic acid in osteosarcoma cells
N Calonghi1, E Pagnotta, C Parolin
1Department of Biochemistry G. Moruzzi, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy.
Biochimica Et Biophysica Acta
|January 20, 2007
Summary
9-hydroxystearic acid (9-HSA) inhibits histone deacetylase 1 (HDAC1), leading to p53 hyperacetylation. This triggers apoptosis and cell cycle arrest in osteosarcoma cells, offering potential therapeutic insights.
Area of Science:
- Biochemistry
- Molecular Biology
- Cancer Research
Background:
- 9-hydroxystearic acid (9-HSA) is a lipid peroxidation by-product that decreases in tumors, potentially disrupting cell division control.
- Previous studies established 9-HSA's role in controlling cell growth and differentiation via histone deacetylase 1 (HDAC1) inhibition.
Purpose of the Study:
- To investigate 9-HSA's effects beyond HDAC1 inhibition, focusing on p53 hyperacetylation and its downstream consequences.
- To elucidate the role of 9-HSA-induced p53 posttranslational modifications in osteosarcoma cell apoptosis and cell cycle arrest.
Main Methods:
- Administration of 9-HSA to U2OS osteosarcoma cells (p53 wild-type).
- Analysis of cell cycle progression (G2/M arrest) and apoptosis induction via mitochondrial pathways.
- Assessment of p53 acetylation status, Bax protein expression (transcriptional and translational levels), and caspase 9 activity.
Main Results:
- 9-HSA induced G2/M cell cycle arrest and apoptosis in U2OS cells.
- HDAC1 inhibition by 9-HSA resulted in p53 hyperacetylation.
- Hyperacetylated p53 led to increased Bax synthesis and translocation to mitochondria, activating caspase 9.
Conclusions:
- 9-HSA's anti-cancer effects in osteosarcoma are mediated through p53 posttranslational modifications, specifically hyperacetylation.
- The mechanism involves HDAC1 inhibition, subsequent p53 acetylation, increased Bax expression, and mitochondrial apoptosis pathway activation.
- These findings highlight 9-HSA as a potential therapeutic agent targeting p53 regulation in cancer.
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