LncRNA-NONHSAT192404.1 Regulates miR-518a-3p to Inhibit Triple-Negative Breast Cancer Progression via the PI3K/AKT Pathway

Introduction: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking targeted therapies. This study aimed to elucidate the role of the long non-coding RNA (lncRNA) NONHSAT192404.1 in TNBC progression and its regulatory relationship with miR-518a-3p and the PI3K/AKT signaling pathway. Methods: Quantitative real-time PCR (qPCR) was used to analyze NONHSAT192404.1 expression in TNBC cell lines. Functional assays, including CCK-8 proliferation, wound-healing, Transwell invasion, flow cytometry, and apoptosis analyses, were performed following NONHSAT192404.1 overexpression. The direct interaction between NONHSAT192404.1 and miR-518a-3p was confirmed using dual-luciferase and RNA pull-down assays. Western blot and qPCR analyses were employed to investigate the regulation of the PI3K/AKT pathway. Results: NONHSAT192404.1 was significantly down-regulated in TNBC cell lines. Its overexpression inhibited cell proliferation, migration, and invasion, and induced cell-cycle arrest and apoptosis. A direct molecular interaction between NONHSAT192404.1 and miR-518a-3p was established. Furthermore, NONHSAT192404.1 was shown to negatively regulate the PI3K/AKT pathway in a miR-518a-3p-dependent manner. Conclusion: These findings highlight NONHSAT192404.1 as a potential tumor suppressor in TNBC and suggest that the NONHSAT192404.1/miR-518a-3p/PI3K/AKT axis may serve as a promising therapeutic target.