Downregulation of microRNA-425-5p suppresses cervical cancer tumorigenesis by targeting AIFM1

Exp Ther Med. 2019 May;17(5):4032-4038. doi: 10.3892/etm.2019.7408. Epub 2019 Mar 18.

Abstract

Although microRNA-425-5p (miR-425-5p) has been previously revealed to be upregulated in cervical cancer, the cellular function of miR-425-5p in cervical cancer remains unknown. The aim of the current study was to investigate the cellular function of miR-425-5p and its underlying mechanism in cervical cancer. Reverse transcription-quantitative polymerase chain reaction was used to measure miR-425-5p expression in several cervical cancer cell lines. TargetScan bioinformatics analysis was used to predict apoptosis-inducing factor mitochondria-associated 1 (AIFM1) as a novel target of miR-425-5p, and this was verified by dual-luciferase reporter assay. Furthermore, cell transfections were used to investigate the role of miR-425-5p in cervical cancer. The effect of miR-425-5p on cell viability and apoptosis in HeLa cells was detected by MTT assay and flow cytometry, respectively. The present study demonstrated that miR-425-5p was significantly upregulated in cervical cancer cell lines. In addition, AIFM1 was identified as a direct target of miR-425-5p and negatively regulated by miR-425-5p. Downregulation of miR-425-5p inhibited HeLa cell viability and induced cell apoptosis. Furthermore, downregulation of miR-425-5p significantly increased the protein and mRNA expression levels of cytochrome c, caspase-3, caspase-9 and DNA damage regulated autophagy modulator 1. The effects of miR-425-5p inhibition on HeLa cell viability and apoptosis were significantly reversed by AIFM1 knockdown. In conclusion, the present study demonstrated that miR-425-5p was upregulated in cervical cancer, and downregulation of miR-425-5p inhibited cervical cancer cell growth by targeting AIFM1.

Keywords: apoptosis; apoptosis-inducing factor mitochondria-associated 1; cell proliferation; cervical cancer; microRNA-425-5p.