α-Tocopheryl succinate stabilizes the structure of tumor vessels by inhibiting angiopoietin-2 expression

Susumu Hama1, Yuriko Okamura1, Kazuho Kamei1

  • 1Department of Biophysical Chemistry, Kyoto Pharmaceutical University, Yamashina-ku, Kyoto, Japan.

Insights

α-Tocopheryl succinate (TS) inhibits tumor angiogenesis by reducing angiopoietin-2 (Ang-2) expression. This action stabilizes newly forming blood vessels, offering potential for well-tolerated anti-cancer therapy.

Area of Science:

  • Oncology
  • Vascular Biology
  • Biochemistry

Background:

  • α-Tocopheryl succinate (TS) exhibits anti-cancer properties, including apoptosis induction and anti-angiogenesis.
  • The precise mechanism by which TS inhibits tumor angiogenesis remains unclear.
  • Understanding TS's molecular targets is crucial for its therapeutic development.

Purpose of the Study:

  • To elucidate the specific step in the angiogenic process targeted by TS.
  • To investigate the effect of TS on angiopoietin (Ang)-1 and Ang-2 expression.
  • To evaluate the anti-angiogenic potential of TS in preclinical models.

Main Methods:

  • TS treatment of mouse melanoma cells.
  • Quantitative analysis of Ang-1 and Ang-2 mRNA and protein levels.
  • Aorta ring and Matrigel plug assays.
  • Immunohistochemical staining and imaging of vascular structures.

Main Results:

  • TS treatment significantly decreased both mRNA and extracellular protein levels of Ang-2.
  • Ang-1 expression levels remained unaffected by TS treatment.
  • Conditioned medium from TS-treated cells inhibited neovascularization and vascular leakage, stabilizing vessels with pericytes.

Conclusions:

  • TS inhibits tumor angiogenesis by suppressing Ang-2 expression.
  • This suppression stabilizes vascular structures in the early stages of angiogenesis.
  • TS demonstrates potential as a well-tolerated anti-angiogenic agent for cancer treatment.

Related Concept Videos

Regulation of Angiogenesis and Blood Supply01:24

Regulation of Angiogenesis and Blood Supply

Rapidly dividing tumors, embryos, and wounded tissues require more oxygen than usual, lowering the oxygen concentration in the blood. At low oxygen or hypoxic conditions, an oxygen-sensitive transcription factor called the hypoxia-inducible factor 1 or HIF1 is activated. HIF1 is a dimeric protein of alpha (ɑ) and beta (β) subunits.  Under optimal oxygen conditions, HIF1β is present in the nucleus while HIF1ɑ remains in the cytosol. HIF1ɑ is hydroxylated by prolyl...
3.3K
Drugs that Stabilize Microtubules01:15

Drugs that Stabilize Microtubules

Microtubules are dynamic structures that undergo cycles of catastrophe and rescue. The microtubules play a central role in cell division by forming the spindle apparatus for segregating the chromosomes. This makes them ideal targets for regulating dividing cells in tumors and malignant cancer cells. Microtubule stabilizing drugs help stabilize the microtubule formation and promote its polymerization. Paclitaxel was the first microtubule stabilizing agent used as anticancer drug in chemotherapy...
2.6K
Mechanism of Angiogenesis01:10

Mechanism of Angiogenesis

Blood vessel formation starts early during embryonic development, around day 7. In the extraembryonic yolk sac, mesodermal precursor cells called hemangioblast proliferate and differentiate into angioblast. Angioblasts express vascular endothelial growth factor receptor 2 or VEGFR2, which binds VEGF-A, a proangiogenic factor, guiding blood vessel formation. VEGF signaling promotes angioblasts to form a blood island in the developing embryo. Angioblasts further differentiate, giving rise to...
6.5K
Drugs that Destabilize Microtubules01:10

Drugs that Destabilize Microtubules

Microtubules are dynamic structures and can be regulated by microtubule targeting agents (MTAs). Microtubule destabilizing drugs are a class of MTAs that destabilize and prevent microtubules' polymerization. Both natural and synthetic chemicals can be found under this class of drugs. Vincristine and vinblastine, two vinca alkaloids, and colchicine were among the first to be discovered. These drugs can affect cells in various ways, either by inducing a change in cell morphology, preventing...
3.6K