MiR-20a-5p suppresses tumor proliferation by targeting autophagy-related gene 7 in neuroblastoma

Abstract

BackgroundNeuroblastoma (NB) is the most common malignant tumor originating from the extracranial sympathetic nervous system in children. The molecular mechanisms underlying this disease are complex, and not completely understood.MethodsQuantitative real-time PCR (qRT-PCR) was applied to quantify the expression of miR-20a-5p and its target gene ATG7 in clinical NB tissues. The biological function of miR-20a-5p and ATG7 in SH-SY5Y cells was investigated through in vitro studies (Real-Time cell kinetic analyzer, colony formation assay, caspase-Glo 3/7 assay and western blotting). The luciferase reporter assay was conducted to verify the biological relationship between miR-20a-5p and ATG7.ResultsHere we found that miR-20a-5p expression was significantly downregulated whereas its target autophagy-related gene 7 (ATG7) was increased along with clinical staging of NB progression. Correlation analysis showed that miR-20a-5p had a negative correlation trend with ATG7. In SH-SY5Y cells, forced expression of miR-20a-5p suppressed ATG7 expression, autophagy initiation and cellular proliferation while promoted apoptosis, suggesting a potential association between miR-20a-5p and ATG7. Further bioinformatic target prediction combined with protein expression and luciferase reporter assay verified that miR-20a-5p inhibited ATG7 by directly binding to its 3′-UTR, confirming the involvement of miR-20a-5p in the regulation of ATG7 in NB.ConclusionsThese results clarified that miR-20a-5p inhibited cell proliferation and promoted apoptosis through negative regulation of ATG7 and thus autophagy suppression in SH-SY5Y cells. Therefore, defining the context-specific roles of autophagy in NB and regulatory mechanisms involved will be critical for developing autophagy-targeted therapeutics against NB. Both miR-20a-5p and ATG7 would be potential therapeutic targets for future NB treatment.

Combined Replenishment of miR‐34a and let‐7b by Targeted Nanoparticles Inhibits Tumor Growth in Neuroblastoma Preclinical Models

“…We tested ten miR‐mimics of candidate TS miRNAs, namely miR‐34a, let‐7b, miR‐96, miR‐101, miR‐184, miR‐542, miR‐591, miR‐628, miR‐885, and miR‐20a, known to be underexpressed in NB, [ 18,26,38–43 ] along with negative controls by transfection of NB cell lines to evaluate cell viability. After pilot reverse transfection experiments with four different concentrations (50 × 10 ‐9 , 30 × 10 ‐9 , 3 × 10 ‐9 , and 0.3 × 10 ‐9 m ) of miR‐mimics, alamarBlue assay showed best results at a 50 × 10 ‐9 m and miR‐34a and let‐7b mimics resulted the most effective to induce a cell growth decrease at 7 d after transfection across the four NB cell lines ( Figure A).…”

Silencing miR‐20a‐5p inhibits axonal growth and neuronal branching and prevents epileptogenesis through RGMa‐RhoA‐mediated synaptic plasticity

“…These four miRNAs regulate tumorigenesis. [33][34][35][36] miR-106b-5p and miR-20a-5p also play important roles in central nervous system diseases. 30,37 Then, the levels of the four miRNAs were detected in PTZ-induced epilepsy rats.…”

Serum miRNAs associated with tumor-promoting cytokines in non-small cell lung cancer

“…Although several studies have revealed the aberrant expression of miR-20a in various types of cancer, data on its function is inconsistent. For example, miR-20a overexpression inhibited the invasion of endometrial cancer cells [ 44 ] and the proliferation of neuroblastoma cells [ 45 ]. In contrast, miR-20a has been found to promote proliferation, invasion, and metastasis in hepatocellular carcinoma [ 46 ] and colorectal cancer cells [ 47 ].…”