Antitumoral efficacy of silver nanoparticles reduced with β-D-glucose on a canine transmissible venereal tumor cell line.

Background: Canine transmissible venereal tumor represents a significant threat to animal health, particularly due to the large global population of stray dogs. The standard treatment for cTVT is chemotherapy, primarily based on vincristine. However, the use of this drug is associated with a high cost of treatment, the development of tumor resistance, and the occurrence of adverse side effects. Therefore, silver nanoparticles have emerged as a potential therapeutic alternative due to their documented cytotoxic effects on various cancer cell lines. Nevertheless, their cytotoxic activity against cTVT has not yet been demonstrated. Methods: In this preliminary study, we evaluated the cytotoxic effects of silver nanoparticles reduced with β-D-glucose on a cTVT cell line. The nanoparticles were characterized by UV-vis spectrophotometry by analyzing absorbance spectra from 200 to 600 nm over a period of 27 days. Cytotoxicity was assessed using the Alamar Blue assay. Reactive oxygen species (ROS) production was measured using a ROS/RNS Detection Kit. Apoptosis was evaluated by immunocytochemical detection of caspase-3 and GAPDH, as well as by fluorescence microscopy using acridine orange/ethidium bromide (AO/EB) and DAPI staining. Additionally, blood samples from three healthy household dogs were collected to evaluate TNF-α production and cytotoxic effects on peripheral blood mononuclear cells (PBMCs). Statistical analyses were performed using one-way ANOVA with GraphPad Prism 6. Results: Silver nanoparticles significantly reduced cell viability in a dose-dependent manner. Treatment affected GAPDH expression as evaluated by immunocytochemistry, increased ROS production, and induced apoptosis, as evidenced by AO/EB and DAPI fluorescence microscopy and caspase-3 expression. Furthermore, cTVT-conditioned medium did not affect plasma TNF-α levels, as determined by ELISA. In addition, no lactate dehydrogenase (LDH) release was observed in PBMC co-culture assays, indicating an absence of cytotoxic effects on non-tumoral cells. Conclusion: Silver nanoparticles reduced with β-D-glucose induce cell death in cTVT cells without triggering an immunogenic response. These findings suggest that this nanomaterial may represent a promising novel therapeutic approach in veterinary oncology.