Osteosarcoma (OS) is an aggressive, metastatic tumor that poses significant treatment challenges in both humans and animals. While natural antitumor agents such as Viscum album and resveratrol have shown dose-dependent cytotoxicity and have reduced proliferation and motility in human OS cells in vitro, their effects on canine and murine OS cells remain untested. This study examined the in vitro antineoplastic activity of resveratrol and homeopathic mistletoe (Viscum album, CH200) compared with doxorubicin, using MTT, Transwell, and annexin/PI assays across canine (D17, UNESP-OSA8), human (SaOS-2), and murine (UMR-106) OS cell lines. All three compounds selectively inhibited cell viability in a dose-dependent manner. The IC50 values were 18.52 μM, 50.29 μM, 37,84 μM, and 24.83 μM for resveratrol; 22.38 μL/mL, 25.19 μL/mL, 31,88 μL/mL, and 28.82 μL/mL for Viscum album CH200; and 398.8 nM, 777.3 nM, 473,5 nM, and 918.1 nM for doxorubicin, depending on the cell line. These concentrations also significantly reduced cell migration, with resveratrol displaying the strongest inhibition. Apoptosis was identified as the primary mode of action for each compound. The results indicate that both resveratrol and Viscum album CH200 can lower cell viability and migration, highlighting their potential as adjuncts to chemotherapy and underscoring the importance of further research into their interactions with standard treatments.
Brasileiro et al. (Fri,) studied this question.