Abstract
Purpose :
The effects of zeaxanthin on uveal melanoma in experimental animal models remain unknown. We found that zeaxanthin inhibited the growth and induced apoptosis of human uveal melanoma cells in vitro. We hypothesize that zeaxanthin may also have effects on uveal melanoma in vivo. The present study investigated the in vivo effects of zeaxanthin on human uveal melanoma in a nude mouse model.
Methods :
Cultured human uveal melanoma cells from an immortal cell line were inoculated into the choroid of nude mice. Mice were randomly divided into control group (without treatment of zeaxanthin), zeaxanthin low group and zeaxanthin high group (treated with intra-choroidal injection of zeaxanthin at 0.171 mg and 0.684 mg, respectively). After 21 days, mice were sacrificed and the eyes enucleated. Gross appearances and tumor mass was determined. Histopathological analysis was performed in hematoxylin and eosin stained frozen sections. Melanoma developed rapidly in the control group.
Results :
Tumor-bearing eye mass in the control group (21.3 ± 3.5 mg, mean±SD) were significantly greater than those in zeaxanthin low group (16.1 ± 3.4 mg) and zeaxanthin high group (12.4 ± 3.2 mg) (P < 0.05). Histopathological study revealed that melanoma in the controlled eyes occupied a large part of the eye, was epithelioid in morphology and with numerous mitotic figures. Scleral perforation and extraocular extension were observed in half of the eyes. Melanomas in zeaxanthin treated eyes were significantly smaller than those in the controls, with many necrosis and apoptosis areas and no extraocular extension could be found. Quantitative image analysis revealed that the tumor size was reduced by 56% in zeaxanthin low group and 92% in zeaxanthin high group as compared to the controls (P < 0.05).
Conclusions :
Our results are consistent with our hypothesis and this study demonstrated that intraocular administration of zeaxanthin significantly inhibits the growth and invasion of human uveal melanoma in nude mice, suggesting that zeaxanthin may be a promising agent to be explored for the prevention and treatment of uveal melanoma.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.