RESUMEN
;Aim To investigate the molecular mechanism of miR-326 inhibiting breast cancer invasion and metastasis by regulating EphB3 expression. Methods RTFQ-PCR was used to examine the expression of miR-326 in normal breast epithelial cells and breast cancer cells and the transfection efficiency of miR-326 overexpression plasmid. EdU cell proliferation assay and Transwell assay were used to examine the changes in proliferation, migration and invasion ability of different subgroups of cells. Dual luciferase assay was used to verify the presence of binding sites for miR-326 and EphB3. Western blot was used to detect the expression of EphB3 in breast cancer cells after overexpression of miR-326. Results RTFQ-PCR results showed that miR-326 was lowly expressed in breast cancer cells and successfully transfected (P < 0. 05). EdU proliferation assay and Transwell assay results showed that overexpression of miR-326 in breast cancer cells inhibited proliferation, migration and invasive ability (P < 0. 05). The results of dual luciferase assay showed that miR-326 could interact with the 3'-UTR of EphB3 (P < 0. 05). Western blot and Transwell assays showed that miR-326 could negatively regulate EphB3 to inhibit invasive metastasis of breast cancer cells (P < 0. 05). Conclusions MiR-326 acts as a cancer suppressor genes in the development of breast cancer and suppresses the invasion and metastasis of breast cancer cells by regulating the expression of EphB3.
RESUMEN
Studies have confirmed that microRNA (miRNAs) is involved in the development and progression of tumors by targeting multiple genes. However, the molecular mechanism of miR-654-5p in in- hibiting the invasion and metastasis of breast cancer cells through the targeted regulation of host cell factor 1 (HCFCl) is still unclear. The analysis of bioinformatics datasets found that miR-654-5p was downregu-lated in breast cancer tissues and was associated with poor prognosis (P = 0. 013). Quantitative real-time PCR (Quantitative real-time PCR, qRT-PCR) showed that the expression of miR-654-5p in MDA-MB-231 cells was decreased (P<0. 05), and the expression of miR-654-5p was significantly increased after transfection of the overexpressed plasmid (P<0. 05) as compared with the control group. The 5-Ethynyl-2'-deoxyuridine (EdU) proliferation experiment and Transwell assay showed that overexpression of miR-654-5p inhibited the proliferation, migration and invasion of MDA-MB-231 cells (P<0. 05). Hub gene HCFCl of miR-654-5p was screened and constructed by Cytoscape software, and it was found that miR-654-5p was negatively correlated with the expression of HCFCl. The expression of HCFCl was increased in breast cancer tissues and closely correlated with lymph node metastasis, and patients with high expression of HCFCl had poor prognosis (P = 0. 0039). Dual-luciferase assay confirmed that miR-654-5p could bind to the 3'-UTR of HCFClmKNA (P<0. 05). Western blot results showed that compared with human normal breast epithelial cells MCF-10A, the expression of HCFCl was increased in MDA-MB-231 cells (P<0. 05), and the expression of HCFCl was significantly down-regulated after overexpression of miR-654-5p (P<0. 05). Transwell experiment results showed that the migration and invasion ability of MDA-MB-231 cells after overexpression of miR-654-5p was significantly decreased compared with the control group. Co-transfection of HCFCl can partially reverse the inhibitory effect of miR-654-5p on the migration and invasion ability of breast cancer cells (P<0. 05). In conclusion, miR-654-5p can inhibit the proliferation, invasion and metastasis of breast cancer cells by regulating the expression of HCFCl.