Objective To investigate the development and metastasis of malignant choroidal melanoma cell strain OCM-1-gfp modified with green fluorescent protein(GFP) and the factors which affected the tumor biological behaviors. Methods GFP was transfected into malignant melanoma cell strain OCM-1.Melanoma cells with high and stable expression of GFP were injected into subretinal space and the subcutaneous space of hind leg of Balb/c nude mouse respectively in order to establish orthotopic and heterotopic transplanted tumor models.The development and metastasis process of orthotopic tumor models was observed directly by fluorescence microscope，and the size of the hypodermal tumor was measured by vernier.The expressions of 13 genes in melanoma were detected by means of immunohistochemistry staining. Results Malignant choroidal melanoma cell strain OCM-1 stably expressed GFP and preserved the characteristics of parental generation，OCM-1-gfp may develop melanoma and continue to metastasize in nude mouse.Positive expression of most of the antibodies，including Rb，p53，p21，E2F，NFkappa;B，cyclin D1，proliferation cellular nuclear antigen（PCNA），bcl2、bclXL/S，bax，and epithelial growth factor（EGF）and its receptor（EGFR），was found.While the staining of inhibition gene p16 was negative. Conclusions GFP is the marker for observing the development and metastasis of malignant choroidal melanoma in vivo.The rate of tumor formation and development process in orthotopic models does not differs much from which in heterotopic models of malignant choroidal melanoma.The expressions of lots of genes in malignant choroidal melanoma developed from OCM-1-gfp including p16、p53、NFkappa;B，cyclin D，PCNA，EGF，and EGFR are abnormal. (Chin J Ocul Fundus Dis, 2006, 22: 170-173)
Objective To establish a new model of orthotopic-transplatation tumor of human malignant choroidal melanoma. Methods pEGFP-N1, the eukaryotic expressive plasmid of green fluorescent protein (GFP), was transfered into human malignant choroidal melanoma cell line (OCM-1) by liposome lipofectanine, then the cell clones with stable GFP expression were screened out by means of neomycin, fluorescence microscope, and flow cytometer. Two μl cell suspension of OCM-1 cells with GFP expression with the density of 4.5×107-5.5×107 cells/ml was injected into the subretinal space of right eyes of 40 nude mice (40 eyes) under binocular operating microscope with left eyes as the control ones. The growth of the transplanted malignant choroidal melanoma was observed in vivo using the fluorescence stereomicroscope. The mice were killed at different time after the operation to observe the metastasis of the tumor to optic nerve, brain and other organs including lung, liver, kidney and spleen. Moreover, pathological detection and immunohistochemical staining of GFP was carried out. Results At the postoperative 10th-12th days, the growths of the transplanted malignant choroidal melanoma with dilated and distorted blood vessels and neovascularization were observed; at the postope rative 20th-22nd days, the melanoma occupied the whole cavity of vitreous body; and at the postoperative 24th-26th days, the transplanted tumor grew out of the eye. Metastases of the carcinoma to olfactory bulb, kidney, lung and liver were seen at the failure phase soon after the extra-ocular phase. The histopathological characteristics of the transplanted tumor were similar to those of human, and the results of immunohistochemical staining showed positive expression of GFP in the tumor cells. Conclusion The orthotopic model of malignant choroidal melanoma set up via injection of human malignant choroidal melanoma cells labeled by GFP into the subretinal space of nude mice may provide a new approach to investigate the natural courses of growth and metastasis of malignant choroidal melanoma. (Chin J Ocul Fundus Dis，2004，20：245-248)