Bufalin Suppresses Head and Neck Cancer Development by Modulating Immune Responses and Targeting the β-Catenin Signaling Pathway

Simple Summary Head and neck cancers are aggressive and challenging to treat due to the severe side effects and toxicity of current treatments. Bufalin, a natural compound from the Chinese toad, has shown promise in fighting various cancers but has not been thoroughly studied for head and neck cancers. Our research aims to explore how bufalin works against these specific cancer cells. By using different techniques, we discovered that bufalin could reduce cancer cell growth, induce cell death, and enhance the body's immune response against tumors. These findings suggest that bufalin could become a new, effective treatment option with potentially fewer side effects for patients with head and neck cancers. This research could pave the way for developing better therapies and improving outcomes for patients facing this difficult disease.Abstract Bufalin, a cardiotonic steroid derived from the Chinese toad (Bufo gargarizans), has demonstrated potent anticancer properties across various cancer types, positioning it as a promising therapeutic candidate. However, comprehensive mechanistic studies specific to head and neck cancers have been lacking. Our study aimed to bridge this gap by investigating bufalin's mechanisms of action in head and neck cancer cells. Using several methods, such as Western blotting, immunofluorescence, and flow cytometry, we observed bufalin's dose-dependent reduction in cell viability, disruption of cell membrane integrity, and inhibition of colony formation in both HPV-positive and HPV-negative cell lines. Bufalin induces apoptosis through the modulation of apoptosis-related proteins, mitochondrial function, and reactive oxygen species production. It also arrests the cell cycle at the G2/M phase and attenuates cell migration while affecting epithelial-mesenchymal transition markers and targeting pivotal signaling pathways, including Wnt/beta-catenin, EGFR, and NF-kappa B. Additionally, bufalin exerted immunomodulatory effects by polarizing macrophages toward the M1 phenotype, bolstering antitumor immune responses. These findings underscore bufalin's potential as a multifaceted therapeutic agent against head and neck cancers, targeting essential pathways involved in proliferation, apoptosis, cell cycle regulation, metastasis, and immune modulation. Further research is warranted to validate these mechanisms and optimize bufalin's clinical application.