Analysis The Expression Of Legumain In Retinoblastoma And Its Relation With Clinicopathological Features And Prognosis

Objective:Legumain is a novel asparaginyl endopeptidase. It was found to be highly expressed in several types of solid tumors. Therefore, the overexpression of Legumain has been shown to be combined with increased migration, invasion and metastasis. However, there is no data available identifying the relationship of Legumain expression and clinicopathologic in retinobla-stoma. This research aims to investigate the expression of the Legumain in retinoblastoma cell lines and specimens, analyze the relationship between Legumain expression, the clinic pathological and prognosis significance.Method:The expression of Legumain in retinoblastoma Y79 and WERI-Rb-1 cell lines was detected by RT-PCR, western-blot and immunofluorescence. The expression of Legumain in retinoblastoma paraffin-embedded tissues was determined by immunohistochemistry. The association between the expression of Legumain and the clinicopathological characteristics including invasion and differentiation was examined by theχ2 method. The association of staining for Legumain and clinicopathological features with patient outcome were evaluated using Kaplan-Meier plots. Comparisons between groups were performed using the log-rank test. Statistical significance was assumed if the P value was less than 0.05. The computer software Statistical Package for the Social Sciences, version 16.0 (SPSS Inc, Chicago, Illinois, USA), was used to run all statistical tests.Results:Legumain mRNA and protein expression in retinoblastoma Y79 cell line was higher than WERI-Rb-1 cell line. Among the 106 tumors, there were 26(24.5%) tumors showed negative expression,42(39.6%) tumors showed weak expression and 38(35.9%) tumors with strong expression. We observed Legumain was highly expressed by tumor vascular endothelial cells in retinoblastoma specimens and highly expressed in optic nerve with invasion. Legumain expression was related to course of disease and invasion of retinoblastoma(p<0.05), especially with the optic nerve invasion(p=0.020). There was no significant change between Legumain expression and sex, age, clinical stage and differentiation (p>0.05). The patients with tumors that showed negative of the Legumain expression had a better prognosis.Conclusion:Legumian were expressed in retinoblastoma cell lines and specimens, The expression levels of Legumain was related to retinoblastoma invasion especially to the degree of optic nerve invasion and have a prognostic value in retinoblastoma. How Legumain have effect on retinoblastoma invasion by angiogenesis and tumor associated macrophages needs further study. Since Legumain and tumor angiogenesis and tumor associated macrophages are closely related to invasion and metastasis of tumor, coupled with its unique restricted specificity, Legumain may represent a potential candidate target for retinoblastoma therapy.