Abstract:

Objective To investigate the relationship between TSP-1 expression and clinical pathological features of uveal melanoma patients and angiogenesis mechanism of uveal melanoma. Design Experimental study. Participants cell line MUM-2B and tissue specimen of uveal melanoma. Method 50 samples of uveal melanoma were collected in Beijing Tongren Hospital. The expression of TSP-1 and CD34 (microvessel density) in the samples was detected using immunohistochemistry. Building the overexpression of TSP-1 lentiviral vector and transfecting the uveal melanoma cell line MUM-2B, the variety expression of VEGF mRNA and protein was detected using Q-PCR and Western Blot. Main Outcome Measures The expression of TSP-1 and microvessel density in the uveal melanoma tissues, the clinical data, and the change of VEGF expression in the cell line before and after the TSP-1 overexpression. Results TSP-1 was positively expressed in 5 samples of 20 patients with ciliary body invasion and 27 samples of 30 patients without ciliary body invasion. There were 3 samples and 29 samples exhibiting the positive expression of TSP-1 in 11 large tumors and 39 medium tumors of uveal melanoma, which were respectively with the significant difference (χ2=5.470, 4.845; P<0.05). No significant differences in the expression of TSP-1 were found between different age, gender, cell type and sclera catheter (P=0.664, 0.606, 0.856, 0.723). The significant differences the microvessel density were found between the positive and negative expression of TSP-1 (Z=-4.616, P<0.05). Building the overexpression of TSP-1 lentiviral vector and transfecting the uveal melanoma cell line MUM-2B, the significant increasing were found in VEGF expression after transfection compared with before the transfecting. Conclusions TSP-1 expression is associated with the uveal melanoma angiogenesis mechanism. The increasing expression of TSP-1 can inhibit the angiogenesis of the tumor. These results imply that TSP-1 expression can be a molecular therapeutic target of uveal melanoma. (Ophthalmol CHN, 2018, 27: 52-57)

Key words: uveal melanoma, thrombospondin-1, angiogenesis mechanism