Overexpression of miR-361-5p in triple-negative breast cancer (TNBC) inhibits migration and invasion by targeting RQCD1 and inhibiting the EGFR/PI3K/Akt pathway

  • Jianjun Han Breast Surgery, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
  • Jingjing Yu Glandular Surgery, Xingtai Third Hospital, Xingtai, Hebei, China
  • Yu'na Dai Breast Surgery, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
  • Jumei Li Breast Surgery, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
  • Meiyan Guo Breast Surgery, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
  • Jingzhen Song Breast Surgery, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
  • Xuefeng Zhou Department of Oncology, Dongtai People’s Hospital, Dongtai, Jiangsu, China
Keywords: miR-361-5p, RQCD1, EGFR/PI3K/Akt signaling pathway, cell migration and invasion, triple-negative breast cancer, TNBC

Abstract

Triple-negative breast cancer (TNBC) is the leading cause of cancer-related death in women. Previous studies indicated that miR-361-5p was downregulated in breast cancer, however, the exact effect of miR-361-5p on TNBC requires further investigation. In the present study, we investigated whether miR-361-5p can act as a tumor suppressor by targeting required for cell differentiation 1 homolog (RQCD1) and inhibiting epidermal growth factor receptor (EGFR)/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway in TNBC. The expression of miR-361-5p and RQCD1 was determined by quantitative reverse transcription PCR (qRT-PCR) and/or western blot in TNBC and the adjacent tissues. miR-361-5p mimics were constructed and transfected to TNBC cell line MDA-MB-231. Cells were divided into three groups: blank control group, miRNA mimic negative control (NC) group, and miR-361-5p mimics group. Expression of miR-361-5p, mRNA and protein expression of PI3K, Akt, EGFR, phosphorylated (p)-EGFR/PI3K/Akt, and protein expression of RQCD1 and matrix metallopeptidase 9 (MMP-9) in MDA-MB-231 were measured by qRT-PCR/western blot after transfection. Cell viability was determined by CCK-8 assay. Cell migration and invasion ability were evaluated by scratch and transwell assay, respectively. miR-361-5p target gene was determined by bioinformatics analysis and luciferase reporter assay. RQCD1 was identified as a target of miR-361-5p by TargetScan and confirmed by luciferase reporter assay. Downregulated miR-361-5p and upregulated RQCD1 were observed in TNBC tissues. Expression of EGFR, PI3K, Akt and MMP-9 was inhibited in cells treated with miR-361-5p mimics. Transfection of miR-361-5p mimics also inhibited the phosphorylation of EGFR, PI3K, and Akt. Suppressed cell viability, migration, and invasion was found in miR-361-5p mimics groups. Our results indicated that overexpression of miR-361-5p might act as a suppressor in TNBC by targeting RQCD1 to inhibit the EGFR/PI3K/Akt signaling pathway.

Downloads

Download data is not yet available.

Author Biography

Xuefeng Zhou, Department of Oncology, Dongtai People’s Hospital, Dongtai, Jiangsu, China
Department of Oncology
Published
2019-02-12
How to Cite
1.
Han J, Yu J, Dai Y, Li J, Guo M, Song J, Zhou X. Overexpression of miR-361-5p in triple-negative breast cancer (TNBC) inhibits migration and invasion by targeting RQCD1 and inhibiting the EGFR/PI3K/Akt pathway. BJBMS [Internet]. 12Feb.2019 [cited 21Feb.2019];19(1):52-9. Available from: https://bjbms.org/ojs/index.php/bjbms/article/view/3399
Section
Molecular Biology