Pigment epithelium-derived factor and vascular endothelial growth factor expression in paraffin-embeded choroidal melanoma tissues

Objective To investigate the expression of pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor (VEGF) in choroidal melanoma. Methods The expression of VEGF and PEDF protein in fifty-eight cases of paraffin-embeded choroidal melanoma samples was measured by immunohistochemistry, the expression of PEDF mRNA in thirty-nine ehoroidal melanoma samples was assayed by in situ hybridization. Results PEDF protein was detected in 13/58 cases (22.4%) of choroidal melanoma, the positive rate in non-sclera-invasion group (12/38, 31.6%) was higher (P<0.05) than that in sclera-invasion group (1/20,5%). VEGF protein was detected in 43/58 cases (64%) of choroidal melanoma, the positive rate in non-sclera-invasion group (25/38, 65.8%) was lower (P<0.05) than that in sclera-invasion group (18/20,90%). The expression of PEDF mRNA was detected in 18/39 (46.2) cases, the positive rate in non-sclera-invasion group was higher (P<0.05) than that in sclera-invasion group. Conclusions Imbalanced expression of VEGF and PEDF in ehoroidal melanoma may play a key role in the angiogenesis, tumor progression and metastasis. Key words: Choroid neoplasms/pathophysiology; Melanoma/etiology; Vascular endothelial growth factors