MiR-145 suppressed human retinoblastoma cell proliferation and invasion by targeting ADAM19

Abstract

MicroRNAs (miRNAs) play critical roles in retinoblastoma (RB) initiation and progression, aberrant expression of miR-145 had been frequently reported in cancer studies. However, the role and mechanism of its function in RB is still unclear. In this study, our data showed that miR-145 was downregulated in RB tissues and cell lines. Overexpression of miR-145 suppressed RB cell proliferation, migration and invasion in vitro. ADAM19 was identified as a direct target of miR-145. Silencing of ADAM19 significantly inhibited RB cell proliferation, migration and invasion. In addition, a reverse correlation between miR-145 and ADAM19 expression was noted in RB tissues. Taken together, these findings suggested that miR-145 functions as a tumor suppressor in RB by directly targeting ADAM19. miR-145 could be an anticancer therapeutic target for RB patients.

Keywords: ADAM19; Retinoblastoma; miR-145.

Figure 1

miR-145 is down-regulated in human retinoblastoma. A. miR-145 expression was significantly down-regulated in RB tissues as compared with normal pediatric retinas. B. miR-145 expression was higher in human normal pediatric retinas than in RB cell lines. *P < 0.05.

Figure 2

miR-145 suppresses cell proliferation, migration and invasion in vitro. A. The relative expression level of miR-145 in Y79 cells transfected with miR-145 mimics or miR-NC was determined by qRT-PCR. B. miR-145 inhibited Y79 cell proliferation, cell proliferation were determined by MTT assay. C. miR-145 decreased migration ability of Y79 cells, cell migration ability were determined by transwell migration assay. D. miR-145 suppressed invasion ability of Y79 cells, cell invasion ability were determined by transwell invasion assay. *P < 0.05.

Figure 3

miR-145 directly targets ADAM19. A. Wild-type (Wt) and mutant (Mut) sequences of the putative miR-145 target sequences of ADAM19 3’-UTR. B. miR-145 significantly inhibited the luciferase activity of the ADAM19 Wt 3’-UTR but not that of the Mut in HEK-293T cells. C. Overexpression of miR-145 reduced the ADAM19 protein levels. *P < 0.05.

Figure 4

ADAM19 inhibition results in similar effects as miR-145 overexpression. A. ADAM19 expression levels were detected by qRT-PCR in Y79 cells transfected with si-ADAM19 or si-NC. B. The proliferation ability of Y79 cells transfected with si-ADAM19 or si-NC was detected by MTT assay. C. The migration ability of Y79 cells transfected with si-ADAM19 or si-NC was detected by transwell migration assay. D. The invasion ability of Y79 cells transfected with si-ADAM19 or si-NC was detected by transwell invasion assay. E. miR-145 expression was inversely correlated with mRNA expression of ADAM19 in RB tissues (Spearman’s correlation analysis, r = -0.75, P < 0.05). *P < 0.05.