Expression and clinical significances of miR-215 and RUNX1 in retinoblastoma

Abstract

Objective To investigate the expression and clinical significances of miR-215 and runt-related protein1 (RUNX1) in retinoblastoma (RB), and to study the regulation effect of miR-215 on RUNX1 in the retinoblastoma cell line PMC-RB. Methods The expressions of miR-215 and RUNX1 in the tumor tissue, non tumor tissues adjacent to cancer, human RB cell line FMC-RB and human normal retinal vascular endothelial cell line ATCC of RB patients were detected by quantitative real-time polymerase chain reaction (qRT-PCR). miR-215 mimics (miR-215-mimic), miR-NC, si-RUNX1 and si-NC were transfected into FMC-RB cell line respectively. Cell proliferation, migration and invasion ability were measured respectively, thus detecting the regulation effect of miR-215 on RUNX1. Results The expression of miR-215 in RB tissues was significantly lower than that in non tumor tissues adjacent to cancer, while the mRNA expression of RUNX1 was higher than that in non tumor tissues adjacent to cancer (P<0.05). The expression of miR-215 in PMC-RB cells was lower than that in ATCC, while the mRNA expression of RUNX1 was higher than that in ATCC (P<0.05). The expression of miR-215 and RUNX1 in RB tumor tissues were closely related to the clinicopathological features of optic nerve infiltration, tumor tissue differentiation and lymph node metastasis (P<0.05). Cell proliferation, migration and invasion in miR-215-mimic group were significantly lower than those in miR-NC group (P<0.05). In transfected 3′ untranslated region (3′UTR)-Wt cells, the luciferase activity in miR-215-mimic group was lower than that in miR-NC group (P<0.05); the expression level of RUNX1 protein in transfected miR-215-mimic cells was lower than that in transfected miR-NC cells (P<0.05). Cell proliferation, migration and invasion in si-RUNX1 group were all lower than those in si-NC group (P<0.05). There was a negative correlation between mRNA expression level of miR-215 and RUNX1 in RB tumor tissues. Conclusions During the occurrence and development of RB, the down-regulation of miR-215 expression can promote malignant progression of tumor by targeting RUNX1. miR-215 can be used as a biological markers and therapeutic target for RB diagnosis. Key words: Retinoblastoma; MicroRNAs; Core binding factor alpha 2 subunit; Cell line, tumor