MiR-182-5p Knockdown Targeting PTEN Inhibits Cell Proliferation and Invasion of Breast Cancer Cells

Purpose: Breast cancer (BC) is one of the most common malignant tumors, affecting a significant number of women worldwide. MicroRNAs (miRNAs) have been reported to play important roles in tumorigenesis. The aim of this study was to determine the roles of miR-182-5p in BC progression. Materials and Methods: The expressions of miR-182-5p and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) were measured in BC tissues and cells by quantitative real-time polymerase chain reaction or Western blot. Cell proliferation and invasion were detected by cell counting kit-8 assay and trans-well assay, respectively. The interaction between milt-1825p and PTEN was probed by bioinformatics analysis, luciferase activity, and RNA immunoprecipitation. A murine xenograft model was established to investigate the role of milt-182-5p in BC progression in vivo. Results: An abundance of mill-182-5p was noted in BC tissues and cells. High expression of milt-182-5p was associated with poor survival. Abrogation of milt-182-5p inhibited cell proliferation and invasion in BC cells. Interestingly, PTEN was indicated as a target of milt-182-5p, and its restoration reversed mill-182-5p-mediated promotion of proliferation and invasion of BC cells. Moreover, depletion of miR-182-5p suppressed tumor growth via up-regulating PTEN expression in the murine xenograft model. Conclusion: MiR-182-5p exhaustion blocked cell proliferation and invasion by regulating PTEN expression, providing a novel therapeutic avenue for treatment of BC.