ABSTRACT
PURPOSE: To determine the effect of adenovirus-mediated gene transfer of a soluble receptor of vascular endothelial growth factor (VEGF) on the growth of experimental eyelid malignant melanoma. METHODS: An adenovirus vector encoding a soluble VEGF receptor/flt-1 (Adflt-ExR) was constructed. The bovine retinal endothelial cells (ECs) were incubated in a culture medium of 293E1 cells infected by means of an adenovirus vector or uninfected (control), which contained human recombinant VEGF, and the [3H]thymidine uptake was tested. The experimental eyelid malignant melanoma was induced by the injection of B16 melanoma cells (4 x 10(6) cells) into the right upper eyelid of BALB/c nu/nu mice, and the size of the tumor was recorded for 3 weeks after tumor cell injection. The effect of Adflt-ExR was examined in three ways. Model 1: B16 cells were infected by Adflt-ExR beforehand (at a multiplicity of infection [MOI] of 10) and injected into the eyelid. Model 2: Adflt-ExR was injected into pre-established B16 cell-induced eyelid malignant melanoma. Model 3: Adflt-ExR was injected into the femoral muscle of mice before B16 cell injection into the eyelid, and the remote effect was evaluated. An adenovirus vector bearing the LacZ gene (AdLacZ) or phosphate-buffered saline was used as a control. The amount of VEGF and the flt-ExR protein was measured by sandwich enzyme-linked immunosorbent assay (ELISA). Vascularization was evaluated by counting the number and the size of the vessels. RESULTS: The supernatant of Adflt-ExR-transfected cells clearly inhibited VEGF-induced bovine retinal EC proliferation in vitro. In models 1 and 2, the tumor growth in Adflt-ExR-treated mice was significantly lower than that of controls (P < 0.05). In model 3, no significant difference was found (P = 0.14). The molar ratio of VEGF/flt-ExR protein was clearly low in the tumors of Adflt-ExR-treated mice in models 1 and 2 (P < 0.01) but not in model 3 (P > 0.05). In vessel density, the tumors in Adflt-ExR-treated mice had fewer vessels than tumors in control animals in models 1 and 2 (P < 0.05). CONCLUSIONS: Adenovirus-mediated gene transfer of a soluble form of VEGF receptor (flt-1) gene inhibited the growth of the experimental eyelid malignant melanoma. This method may be useful as an antiangiogenic therapy for eyelid malignant melanoma.
Subject(s)
Eyelid Neoplasms/prevention & control , Gene Transfer Techniques , Genetic Therapy , Melanoma/prevention & control , Proto-Oncogene Proteins/genetics , Receptor Protein-Tyrosine Kinases/genetics , Receptors, Growth Factor/genetics , Adenoviridae/genetics , Animals , Cattle , Endothelial Growth Factors/metabolism , Endothelium, Vascular/metabolism , Enzyme-Linked Immunosorbent Assay , Eyelid Neoplasms/blood supply , Eyelid Neoplasms/metabolism , Eyelid Neoplasms/pathology , Genetic Vectors , Humans , Lac Operon/genetics , Lymphokines/metabolism , Male , Melanoma/blood supply , Melanoma/metabolism , Melanoma/pathology , Mice , Mice, Inbred BALB C , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Neovascularization, Pathologic/prevention & control , Proto-Oncogene Proteins/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Growth Factor/metabolism , Retinal Vessels/metabolism , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factor Receptor-1 , Vascular Endothelial Growth FactorsABSTRACT
BACKGROUND: The pathogenesis of age-related macular degeneration (AMD) remains unknown. Genetic and environmental factors are thought to be associated with AMD. Although some studies have reported familial cases of AMD in the United States, as far as we know, familial cases of AMD have rarely been reported in Japan. CASES: We describe three families with two members of each family affected with AMD and one family with three affected members. OBSERVATIONS: In one family, two siblings were affected with AMD with choroidal neovascularization and two other siblings had retinal pigment epithelial abnormalities or drusen of the maculas, suggesting the heterogeneity of the maculas in the family. However, the other families did not show such heterogeneity of the fundus. Among the four families, six of nine affected individuals had a smoking habit, a risk factor for AMD. CONCLUSIONS: These findings suggest that the development and progression of AMD might be associated with genetic factors and environmental factors.
