The crucial role of DNA-dependent protein kinase and myelin transcription factor 1-like protein in the miR-141 tumor suppressor network

The inhibitory role of microRNA-141-3p in human cutaneous melanoma growth and metastasis through the fibroblast growth factor 13-mediated mitogen-activated protein kinase axis

Human cutaneous melanoma (CM) is a highly invasive malignancy arising from melanocytes, and accompanied by ever-increasing incidence and mortality rates worldwide. Interestingly, microRNAs (miRNAs) possess the ability to regulate CM cell biological functions, resulting in the aggressive progression of CM. Nevertheless, a comprehensive understanding of the underlying mechanism remains elusive. Accordingly, the current study sought to elicit the functional role of miR-141-3p in human CM cells in association with fibroblast growth factor 13 (FGF13) and the MAPK pathway. First, miR-141-3p expression patterns were detected in human CM tissues and cell lines, in addition to the validation of the targeting relationship between miR-141-3p and FGF13. Subsequently, loss- and gain-of-function studies of miR-141-3p were performed to elucidate the functional role of miR-141-3p in the malignant features of CM cells. Intriguingly, our findings revealed that FGF13 was highly expressed, whereas miR-141-3p was poorly expressed in the CM tissues and cells. Further analysis highlighted FGF13 as a target gene of miR-141-3p. Meanwhile, overexpression of miR-141-3p inhibited the proliferative, invasive, and migratory abilities of CM cells, while enhancing their apoptosis accompanied by downregulation of FGF13 and the MAPK pathway-related genes. Collectively, our findings highlighted the inhibitory effects of miR-141-3p on CM cell malignant properties via disruption of the FGF13-dependent MAPK pathway, suggesting a potential target for treating human CM.

Bone Marrow Mesenchymal Stem Cell (BMSC)-Exosomes Overexpressing miR-141 Inhibit the Malignant Biological Behavior of Glioma Cells via Wnt Signaling

Our study explores whether BMSC-exosomes overexpressing miR-141 can regulate Wnt signal to inhibit the malignant biological behavior of glioma cells. Thirty healthy mice were selected to construct a glioma mouse model and assigned randomly into the control group, miR-141 NC group, and miR-141 mimic group followed by analysis of cell proliferation, apoptosis, protein expression and mRNA expression by MTT method, flow cytometry, Western blot and RT-PCR methods. Compared with the other two groups, miR-141 mimic group showed reduced number of cell proliferation at 24 h and 48 h, decreased cell migration and invasion ability, and the increased cell apoptosis rate (P < 0.05). In miR-141 mimic group, the protein expression of miR-141 was the highest, while the protein expression of β-catenin, survivin and c-myc was the lowest (P < 0.05). In conclusion, BMSC-exosomes overexpressing miR-141 can inhibit the malignant biological behavior of GC cells possibly by inhibiting the activation of Wnt signaling pathway.

miRNA-338-3p inhibits glioma cell proliferation and progression by targeting MYT1L

Glioma is a common and aggressive primary malignant brain tumor. MicroRNAs (miRNAs) play key roles in the post-transcriptional regulation of gene expression. Currently, miRNAs are considered to be useful biomarkers for the diagnosis and prognosis of glioma. Previously, we screened three differentially expressed miRNAs from Gene Expression Omnibus (GEO) database which included miRNA-338-3p. miRNA-338-3p is involved in tumor development in different cancers. However, in glioma, its function and its underlying mechanism remain unclear. We found that overexpression of miRNA-338-3p suppressed cell proliferation, migration, invasion, and promoted apoptosis of glioma in vitro. Myelin transcription factor 1-like (MYT1L) was found to be a direct target of miRNA-383-3p in glioma cells as the expression of MYT1L was inhibited by overexpressing miRNA-338-3p. Additionally, silencing MYT1L produced similar effects as overexpressing miRNA-338-3p in glioma cells. Overexpression of MYT1L also completely attenuated the inhibitory effect induced by miRNA-338-3p overexpression. These results suggest that the miRNA-338-3p/ MYT1L axis plays a critical role in the progression of glioma. Our study delineates one of the complex molecular mechanisms that drive the growth of glioma and may be useful in finding novel prognostic predictors and treatment targets in glioma. AVAILABILITY OF DATA AND MATERIALS: All data generated or analysed during this study are included in this published article.