RESUMO
Recent evidences demonstrate that dysregulated expression of microRNA-320d (miR-320d) has been associated with several cancer development and progression. However the effect of miR-320d on gastric cardiac adenocarcinoma (GCA) and the association of miR-320d with its potential gene target FoxM1 remain unclear. Here, we evaluated expression profile of miR-320d and FoxM1 in 60 human GCA tissues and GCA cell lines (OE-19 and SK-GT2). Immunohistochemistry, qualitative PCR and western-blotting were performed in GCA tissues to detect the expression level of miR-320d and FoxM1. CCK-8, transwell, wound-healing assays, and in vivo experiments were conducted using GCA cells that treated with miR-320d mimics or inhibitors to evaluate the biological functions of miR-320d. Luciferase reporter assay was conducted to confirm possible binding sites of FoxM1 for miR-320d. Compared with paired non-cancerous tissues, it showed that miR-320d expression was significantly decreased in GCA specimens (P < 0.0001), while FoxM1 was significantly upregulated in GCA tissues (P < 0.0001). Modulating miR-320d function by transfection of miR-320 mimics or inhibitor led to inhibition or promotion of GCA cell proliferation and invasion, thus regulating tumor progression in GCA-tumor bearing mice. The mechanism analysis of miR-320d/FoxM1 showed that FoxM1 has two miR-320d binding sites in its 3'-untranslated region (3'-UTR), that contributes to regulation of the cell biological behaviors. Taken together, our data suggested that miR-320d acts as a tumor suppressor in GCA by directly targeting FoxM1 and thus potentially serves as a biomarker for anti-GCA therapy in GCA patients.
RESUMO
[Objective]To investigate the inhibitory effect and mechanism of the microRNA-320d(miR-320d)on epithelial mesenchymal transition in endometrial carcinoma JEC cells.[Methods]JEC endometrial carcinoma cell lines were transfected with miR-320d mimics or negative control mimic,respectively,as M320d or NCM group. Control group was established with untreated JEC endometrial carcinoma cells. miR-320d content in each group was detected by RT-PCR method. Transwell assay was used to detect the migration and invasion ability of the 3 groups. Western-blot assay was used to detect the expressions ofα-Catenin,E-cad-herin,Vimentin and PBX3 protein in 3 groups. Antagonistic effect of PBX3 overexpression on miR-320d inhibition of EMT was detect-ed by western blot assay. The relationship between miR-320d and PBX3 was detected by dual luciferase assay.[Results]The expres-sion level of miR-320d in M320d group was significantly up-regulated,and the expression level of miR-320d was 808.25 ± 15.58 times higher than that of control group(P<0.05). The number of migrating cells in M320d group was 29.56 ± 0.59,which was signif-icantly lower than that of control group at 94.48 ± 1.02(P < 0.05). The number of invasive cells in M320d group was 7.33 ± 0.84, which was significantly lower than that of group control 86.28 ± 3.51(P < 0.05). Compared with control group ,the expression of α-Catenin and E-cadherin protein was significantly increased ,the expression of Vimentin protein was significantly decreased ,and the expression of PBX3 protein was significantly decreased. After PBX3 overexpression,the expression ofα-Catenin and E-cadherin protein were significantly decreased,the expression of Vimentin protein were significantly increased. Dual luciferase assay showed that PBX3 is a downstream target gene of miR-320d(P<0.05).[Conclusion]miR-320d may inhibit the expression of EMT related protein through the downstream target gene PBX3 and inhibit the epithelial mesenchymal transition function of endometrial carcinoma JEC cells.
