ABSTRACT
This study was designed to investigate the inhibitory effect and mechanism of neferine (Nef) on invasion and metastasis of nasopharyngeal carcinoma cells (NPC). The viability of CNE-1 and 5-8F cells was detected by CCK-8 assay after treatment with different concentrations of Nef. The effects of Nef on cell migration and invasion were detected by the scratch test and Transwell assay. Western blot analysis was used to detect the effects of Nef on levels of epithelial-mesenchymal transition (EMT)-associated proteins and transcription factors. The differentially expressed gene profiles between control group and Nef group were analyzed by microRNA microarray, combined with bioinformation analysis. It was observed that 30 μmol·L-1 Nef had no significant effect on the viability of CNE-1 and 5-8F cells. Western blot assay showed that the expression level of neurotroponin cadherin (N-cadherin) and vimentin decreased after treatment with Nef, while the expression of epithelial cadherin (E-cadherin) increased. The expression of transcription factors including Twist, Snail, and Slug exhibited no significant difference. Results of the microRNA microarray suggest that 10 microRNAs showed significant differences when compared with the control group. Bioinformatics analysis showed that hsa-let-7c-5p and hsa-microRNA-423-5p targeted the same downstream genes: small integral membrane protein 3 (SMIM3) and nerve growth factor (NGF). Overexpression of hsa-let-7c-5p and hsa-miR-423-5p promoted the invasion and migration ability of 5-8F cells and decreased the expression of SMIM3 and NGF. The results from this study suggest that Nef may inhibit the invasion and metastasis of NPC cells by inhibiting the expression of hsa-let-7c-5p and hsa-miR-423-5p followed by the upregulation of SMIM3 and NGF; thus, regulating the expression of EMT-associated proteins. Our data have provided experimental evidence for the inhibition of tumor invasion and metastasis by Nef.