miR-877-5p Inhibits Epithelial Mesenchymal Transformation of Breast Cancer Cells by Targeting FGB.

Purpose: This present study is aimed at exploring the FGB expression in breast cancer (BC) and the role of FGB in BC.

Methods: A total of 150 pairs of BC tissues and adjacent tissues from BC surgery patients were collected. RT-qPCR was utilized to evaluate the mRNA expression of FGB and miR-877-5p. Immunohistochemistry was applied to evaluate the protein expression of FGB. Chi-square test was performed to evaluate the relationship between FGB expression level and clinical characteristics. Cell proliferation was examined using CCK-8 assay. Cell invasion was evaluated by transwell assay. Flow cytometry assay was applied to measure cell apoptosis. The protein expression was evaluated by western blot. BALB/C nude mice were used to establish the xenograft tumor model.

Results: FGB was more highly expressed in BC tumor, and the expression of FGB was relevant to TNM stage and lymph node metastasis and showed a positive correlation. FGB was proved to be directly regulated via miR-877-5p and enhanced proliferation and invasion of BC cells. FGB downregulation markedly inhibited the tumor growth, including tumor weight and volume. In addition, the Ki-67 expression was observably declined in the sh-FGB group. The protein expression of E-cadherin was markedly raised in the sh-FGB group while the protein expression of N-cadherin and vimentin was markedly declined in the sh-FGB group.

Conclusion: In conclusion, miR-877-5p inhibits epithelial mesenchymal transformation, cell proliferation, and invasion of BC cells via downregulating FGB.