miR-34a Enhances the Susceptibility of Gastric Cancer to Platycodin D by Targeting Survivin.

INTRODUCTION: Platycodin D (PD), a triterpenoid saponin isolated from Platycodon grandiflorum, has a well-known anti-tumor effect in multiple human cancers, including gastric cancer (GC). miR-34a plays an important role in the progression of GC. However, the relationship between miR-34a and the susceptibility of GC cells to PD is still unclear. The aim of our research was to investigate the functions of miR-34a in mediating the susceptibility of GC to PD. METHODS: qPCR was performed to detect the expression level of miR-34a and survivin in GC cells. The expression of survivin, Bcl-2, Bax, and cleaved caspase-3 was analyzed using Western blot. Cell viability was detected by MTT assay, and apoptosis was analyzed via Annexin V-FITC/PI staining followed by flow cy-tometry. The colony formation and scratch-wound assays were applied to assess cell proliferation and migration. Caspase-3/7 activity was detected by a Caspase-Glo®3/7 detection kit. The relationship between miR-34a and survivin was determined by dual luciferase reporter gene assay. Finally, a GC xenograft mouse model was used to confirm our findings in vivo. RESULTS: The expression of miR-34a decreased but survivin increased inversely in human GC cells. Survivin is a direct target of miR-34a and may be negatively regulated by miR-34a. PD could inhibit GC cell proliferation and induce apoptosis. Importantly, overexpression miR-34a or suppressing survivin was shown to enhance the susceptibility of GC to PD both in vitro and in vivo. CONCLUSIONS: miR-34a could modulate the susceptibility of GC to PD via targeting survivin, suggesting miR-34a overexpression may serve as a novel strategy to sensitize GC to anti-cancer drugs.

[Inhibition of Yiqi Jiedu formula on proliferation of nasopharyngeal carcinoma cells by MAPK/ERK signaling pathway].

To study the effect of aqueous extracts of Yiqi Jiedu formula (YQ) on the proliferation of CNE2 cells in human nasopharyngeal carcinoma, and investigate its mechanism to provide a new theoretical basis for the clinical application of YQ. CNE2 cells were treated with different concentrations (0.125, 0.25, 0.5, 0.25 g·L⁻¹) of YQ, positive control medicine (cisplatin 4.0 mg·L⁻¹), inhibitor PD98059 (50 µmol·L⁻¹), activator isoproterenol hydrochloride (20 µmol·L⁻¹), activator isoproterenol hydrochloride (ISO)+YQ 0.5 g·L⁻¹. Then cell labeling by using real-time analyzer (RTCA) and CCK 8 method were used to detect cell proliferation activity, and the half inhibitory concentration (IC50) was calculated. The cell cycle distribution was detected by fluorescence double dye flow cytometry PI staining, and Western blot method was used to detect the expression levels of related protein and MAPK/ERK signaling pathway. The results of RTCA and CCK-8 test showed that as compared with the control group, YQ group could effectively inhibit the proliferation of CNE2 cells (P<0.01), with a dose and time dependence, and 48 h IC50 value was 0.5 g·L⁻¹. The results of cell cycle showed that after 48 h of water extract treatment, the cell cycle was significantly changed, the proportion of G0/G1 was reduced, the ratio of G2/M increased, and the cell cycle was in G2/M period (P<0.01). Western blot results showed that after 48 h treatment with different concentrations of aqueous extract, cell cycle-related proteins cyclinD1, cyclinD3 and CDK2 expression levels were down-regulated; MAPK/ERK signaling pathway related protein p-c-Raf, p-MEK, p-ERK1/2 expression level significantly lower as compared with the control group (P<0.05). After adding activator and inhibitor in MAPK/ERK signaling pathway on this basis, the results showed that after adding activator ISO, cell proliferation was significantly higher than that in the Control group; the cycle related proteins cyclinD1, cyclinD3, and CDK2 expression levels were increased; at the same time, key protein p-c-Raf, p-MEK, p-ERK1/2 expression levels in the signal pathways were relatively increased. While after the addition of inhibitor PD98059, the cell proliferation was significantly lower than that in the Control group, and the expression level of corresponding protein was decreased, which was significantly different from the Control group (P<0.05). So YQ could block cell cycle and inhibit the proliferation of CNE2 cells mainly by reducing the expression of MAPK/ERK signaling pathway key protein p-c-Raf, p-MEK and p-ERK1/2.

Anti-Nasopharyngeal carcinoma mechanism of sanguinarine based on network pharmacology and molecular docking.

BACKGROUND: The purpose of this study was to investigate the mechanism of sanguinarine (SAN) against nasopharyngeal carcinoma (NPC) by means of network pharmacology, molecular docking technique, and experimental verification. METHODS: The SAN action targets were predicted using the Swiss Target Prediction database, the related NPC targets were determined using the GEO database, and the intersection of drug and disease pathway targets were considered to be the potential targets of SAN against NPC. The target-protein interaction network map was constructed using the STRING database, and the core target genes of SAN against NPC were obtained via topological network analysis. "R" language gene ontology (GO) function and Kyoto encyclopedia of genes and genome (KEGG) pathway enrichment analyses were used to dock the core target genes with SAN with the help of AutodockVina. Cell proliferation was detected using MTT and xCELLigence real-time cell analysis. Apoptosis was identified via Hoechst 33342 staining, JC-1 mitochondrial membrane staining, and annexin V-FITC/PI double fluorescence staining, while protein expression was quantified using western blotting. RESULTS: A total of 95 SAN against NPC targets were obtained using target intersection, and 8 core targets were obtained by topological analysis and included EGFR, TP53, F2, FN1, PLAU, MMP9, SERPINE1, and CDK1. Gene ontology enrichment analysis identified 530 items, and 42 items were obtained by Kyoto encyclopedia of genes and genome pathway enrichment analysis and were mainly related to the PI3K/AKT, MAPK, and p53 signaling pathways. Molecular docking results showed that SAN had good binding activity to the core target. SAN inhibited the proliferation of NPC cells, induced apoptosis, reduced the expression levels of survivin and Bcl2, and increased the expression levels of Bax and cleaved caspase-8. It also decreased the expression levels of the key proteins p-c-Raf, p-MEK, and p-ERK1/2 in the MAPK/ERK signaling pathway in NPC cells. CONCLUSION: SAN inhibits the proliferation and induces the apoptosis of NPC cells through the MAPK/ERK signaling pathway.