Grifola frondose Polysaccharide Regulates Proliferation, Migration and Invasion of Gallbladder Cancer Cells Through LncRNA HULC/miR-186-5p Axis

Objective: To analyze the effects of Grifola frondose polysaccharide (GFP) on proliferation, migration and invasion of gallbladder carcinoma cells and its mechanism. Methods: Logarithmic phase GBC-SD cells randomized: Control group, GFP group (0.5, 1,2 µg/mL GFP), shNC group, shHULC group, miR-NC group, miR-186-5p mimics group, GFP+pcDNA group, GFP+pcDNA-HULC group. Cell inhibition rate was detected by CCK-8 method. The migration and invasion of GBC-SD cells were detected by Transwell cell assay. The protein levels of Cyclin D1, P21, MMP-2 and MM-9 were detected by Western Blot. LncRNA HULC and miR-186-5p levels were detected by qRT-PCR. Starbase online software predicted the binding sites of HULC and miR-186-5p, dual luciferase reporting assay was used to detect the targeting relationship between LncRNA HULC and miR-186-5p. The effect of GFP on the endogenetic growth of GBC-SD cells was detected by tumor transplantation in nude mice. Results: 0.25~8 µg/mL GFP had definite inhibitory effect on GBC-SD cells of gallbladder carcinoma. Compared with the control group, 0.5, 1 and 2 µg/mL of GFP (extremely) significant (P<0.05, P<0.01) inhibited the migration and invasion of GBC-SD cells, and (extremely) significant (P<0.05, P<0.01) decreased the levels of Cyclin D1, P21, MMP-2 and MM-9, extremely significant increased the levels of P21 (P<0.05, P<0.01). The expression of LncRNA HULC was extremely significant down-regulated and miR-186-5p was extremely significant up-regulated (P<0.05, P<0.01). Starbase online software predicted that there was a binding site between HULC and miR-186-5p, and compared with miR-NC group, the luciferase activity of HULC-WT in miR-186-5p mimics group was extremely significant (P<0.01) decreased. There was no significant difference in the luciferase activity of HULC-MUT (P>0.05). Compared with shNC group, the relative expression level of HULC in shHULC group was extremely significant (P<0.01) decreased, the relative expression level of miR-186-5p was extremely significant (P<0.01) increased, the cell survival rate, migration number and invasion number were significantly (P<0.05) decreased, respectively, the levels of MMP-2, MMP-2 and MM-9 were extremely significant decreased (P<0.01). Compared with GFP+pcDNA group, the inhibition rate of GFP+pcDN-HULC group significantly decreased (P<0.05), and the number of migration and invasion was significantly increased (P<0.01), the CylinD1, MMP-2 and MM-9 levels were significantly increased (P<0.05, P<0.01). Compared with GFP+pcDNA administration group, tumor volume and mass in GFP+pcDN-HULC administration group were significantly (P<0.05) increased, and miR-186-5p levels were extremely significantly decreased (P<0.01). Conclusion: GFP could inhibit proliferation, invasion and migration of gallbladder cancer cells, and its mechanism was related to the regulation of LncRNA HULC/miR-186-5p.