The silencing of long non-coding RNA ANRIL suppresses invasion, and promotes apoptosis of retinoblastoma cells through the ATM-E2F1 signaling pathway.

Yang Yang,Xiao-Wei Peng

doi:10.1042/bsr20180558

Abstract

As one of the most common primary intraocular carcinomas, retinoblastoma generally stems from the inactivation of the retinoblastoma RB1 gene in retinal cells. Antisense non-coding RNA in the INK4 locus (ANRIL), a long non-coding RNA (lncRNA), has been reported to affect tumorigenesis and progression of various cancers, including gastric cancer and non-small cell lung cancer. However, limited investigations emphasized the role of ANRIL in human retinoblastoma. Hence, the current study was intended to investigate the effects of ANRIL on the proliferation, apoptosis, and invasion of retinoblastoma HXO-RB44 and Y79 cells. The lentivirus-based packaging system was designed to aid the up-regulation of ANRIL and ATM expressions or employed for the down-regulation of ANRIL in human retinoblastoma cells. Afterward, ANRIL expression, mRNA and protein expression of ATM and E2F1, and protein expression of INK4b, INK4a, alternate reading frame (ARF), p53 and retinoblastoma protein (pRB) were determined in order to elucidate the regulation effect associated with ANRIL on the ATM-E2F1 signaling pathway. In addition, cell viability, apoptosis, and invasion were detected accordingly. The results indicated that the down-regulation of ANRIL or up-regulation of ATM led to an increase in the expressions of ATM, E2F1, INK4b, INK4a, ARF, p53, and pRB. The silencing of ANRIL or up-regulation of ATM exerted an inhibitory effect on the proliferation and invasion while improving the apoptosis of HXO-RB44 and Y79 cells. In conclusion, the key observations of our study demonstrated that ANRIL depletion could act to suppress retinoblastoma progression by activating the ATM-E2F1 signaling pathway. These results provide a potentially promising basis for the targetted intervention treatment of human retinoblastoma.

Highlights

Retinoblastoma is an aggressive form of an intraocular cancer usually occurring during childhood that is initiated by the mutation of the RB1 gene
As GFP was carried by the pCD513B-Antisense non-coding RNA in the INK4 locus (ANRIL), green fluorescence in HXO-RB44 could be observed under a fluorescence microscope in the event that the cells were transfected
On the sixth day, the cell viability increased in the overexpressed ANRIL group, while it decreased in the sh-ANRIL group and the overexpressed ATM group when compared with the control and negative control (NC) groups; no significant difference was detected in the overexpressed ATM + overexpressed ANRIL group (P>0.05). These results demonstrated that ANRIL silencing could act to suppress the cell proliferation of HXO-RB44 and Y79 by activating the ATM-E2F1 signaling pathway

Summary

Introduction

Retinoblastoma is an aggressive form of an intraocular cancer usually occurring during childhood that is initiated by the mutation of the RB1 gene. Diagnoses along with early treatment may boast excellent outcome, retinoblastoma may be a life-threatening condition if left without a swift and adequate treatment [1,2]. An investigation into retinoblastoma survival in less-developed countries, suggested there to be an estimated survival rate of 40% in lower income countries with survival rates approximately 77% and 79% in lower MICs and upper MICs, respectively [4]. The treatment for retinoblastoma generally c 2018 The Author(s).

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