In vitro Multi-targeted Anti-cancer Effects of Bavachinin in Papillary Thyroid Carcinoma Cell Line: Dual Pathway Inhibition and Cytokine Downregulation

Objectives: The aim of this study is to evaluate the anti-cancer activity of bavachinin in the papillary thyroid carcinoma TPC-1 cell line and elucidate its underlying molecular mechanisms. Methods: TPC-1 cells were treated with bavachinin (5 - 20 μM) for 24 - 72 hours. Cell viability was assessed using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT assay); morphological changes were visualized by confocal microscopy. Migration and invasion were analyzed by wound-healing and Transwell assays, respectively. Cytokine secretion was measured using enzyme-linked immunosorbent assay (ELISA). Gene and protein expression levels of protein kinase B (AKT), mechanistic target of rapamycin (mTOR), extracellular signal-regulated kinase 1/2 (ERK1/2), and c-Jun N-terminal kinase (JNK) were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. Apoptosis was confirmed by assessing the B-cell lymphoma-2-associated X protein (BAX)/B-cell lymphoma-2 (BCL-2) ratio and cleaved caspase-3 activity. All experiments were performed in triplicate, and data are presented as mean ± standard deviation (SD). Statistical significance was determined by one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test (P < 0.05). Results: Bavachinin significantly reduced cell viability, migration, and invasion in a dose-dependent manner (20 μM reduced viability by approximately 50% at 72 hours, P < 0.01). It suppressed the phosphorylation of AKT and ERK1/2, downregulated mTOR expression, and decreased secretion of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β). Apoptosis was confirmed by an increased BAX/BCL-2 ratio and elevated cleaved caspase-3 levels. Conclusions: Bavachinin exerts multi-targeted anti-cancer effects in thyroid carcinoma cells through dual inhibition of the phosphoinositide-3-kinase (PI3K)/AKT/mTOR and mitogen-activated protein kinase (MAPK)/ERK pathways, along with suppression of pro-inflammatory cytokines, culminating in apoptosis and impaired invasiveness.