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Updated: Aug 12, 2026
Rat Mesentery Angiogenesis Assay
Published on: June 18, 2011
Vitamin D inhibits angiogenesis in transgenic murine retinoblastoma
M T Shokravi1, D M Marcus, J Alroy
1Howe Laboratory of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston.
Purpose:
Vitamin D compounds have been shown to inhibit tumor growth in a transgenic retinoblastoma murine model. The mechanism of action has not been defined clearly, although an antiangiogenic action has been proposed.
Methods:
Transgenic retinoblastoma mice received high (0.05 microgram) and low (0.025 microgram) doses of vitamin D3 by intraperitoneal injection 5 times per week for 5 weeks. Control animals were injected with mineral oil vehicle alone. At 5 months of age, the animals were killed and eyes were enucleated and processed for light microscopy. Paraffin-embedded sections were stained with an immunoperoxidase stain (GS-1) specific for mammalian vascular endothelium. Sections were graded by a single masked reviewer, and intraobserver reliability was assessed. Mean vessel counts were made for each group.
Results:
The high-dose group had the lowest mean vessel count (8.5), followed by the low-dose group (10.1). The control group had the highest mean vessel count (14.1). Vitamin D-treated animals (high- and low-dose groups combined) had significantly fewer vessels P = 0.001) than untreated controls.
Conclusions:
These results support the hypothesis that inhibition of angiogenesis is a mechanism of action for vitamin D in the transgenic retinoblastoma mouse model.
Insights
Vitamin D3 administration significantly reduced blood vessel formation in a mouse model of retinoblastoma. These findings support vitamin D
Area of Science:
- Oncology
- Ophthalmology
- Pharmacology
Background:
- Retinoblastoma is a pediatric eye cancer.
- Vitamin D's role in tumor inhibition is under investigation.
- Antiangiogenic effects of vitamin D have been proposed.
Purpose of the Study:
- To investigate the antiangiogenic effects of vitamin D in a transgenic retinoblastoma mouse model.
- To determine if vitamin D inhibits tumor growth by reducing angiogenesis.
Main Methods:
- Transgenic retinoblastoma mice received high or low doses of vitamin D3 via intraperitoneal injection for 5 weeks.
- Control mice received mineral oil vehicle.
- Eyes were processed for light microscopy and stained for vascular endothelium (GS-1).
- Mean vessel counts were compared between groups.
Main Results:
- Vitamin D treatment significantly reduced the mean number of blood vessels in the eyes of treated mice compared to controls (P = 0.001).
- The high-dose vitamin D3 group exhibited the lowest mean vessel count (8.5), followed by the low-dose group (10.1).
- The control group had the highest mean vessel count (14.1).
Conclusions:
- The results support the hypothesis that vitamin D inhibits retinoblastoma tumor growth by suppressing angiogenesis.
- Vitamin D may represent a therapeutic agent for retinoblastoma through its antiangiogenic properties.
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