Background This study aimed to investigate the effects of miR-451 on proliferation, invasion, and migration in the papillary thyroid carcinoma (PTC) cell line TPC-1, focusing on its regulatory role in the PI3K/AKT/mTOR signaling pathway. Methods TPC-1 cells were transfected with siRNA-NC, miR-451 mimic, or miR-451 inhibitor, and treated with the PI3K activator 740Y-P (miR-451 mimic+740Y-P) where indicated. Cell proliferation, migration, and invasion were assessed using MTT, wound healing, and Transwell assays, respectively. Protein expression and pathway activation were analyzed by Western blot. Results Compared to the Blank and siRNA-NC groups, the miR-451 mimic group showed significantly lower expression of Bcl-2, p-PI3K, p-AKT, and p-mTOR proteins, along with significantly higher expression of Bax (P < 0.05). Conversely, the miR-451 inhibitor group exhibited significantly elevated levels of Bcl-2, p-PI3K, p-AKT, and p-mTOR, and significantly reduced Bax expression (P < 0.05). Furthermore, compared with the miR-451 mimic group, the miR-451 mimic + 740Y-P group displayed significantly increased expression of Bcl-2, p-PI3K, p-AKT, and p-mTOR, along with significantly decreased Bax levels (P < 0.05). Conclusions miR-451 expression is significantly reduced in PTC tissues and TPC-1 cells. Overexpression of miR-451 inhibits proliferation, invasion, and migration in TPC-1 cells, likely via the PI3K/AKT/mTOR signaling pathway, suggesting its potential as a molecular target for further investigation in PTC.
Jiao et al. (Wed,) studied this question.