The present study was designed to evaluate the effect of SB injection, which is composed of extracts from the roots of Pulsatilla koreana, Panax ginseng, and Glycyrrhiza glabra, on the viability of canine osteosarcoma and melanoma cells and nonneoplastic canine cells. Cells were treated with SB injection, conventional chemotherapeutic drugs, or a combination of both at various concentrations. Cellular viability was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry was used to evaluate the cell cycle and apoptosis. SB injection inhibited the growth of osteosarcoma and melanoma cells in a dose-dependent manner. The cell cycle of the affected cells was arrested in the G2/M phase, indicating an anti-proliferative effect. SB injection dose-dependently increased the rate of apoptosis. Furthermore, we found that combining SB injection with chemotherapeutic drugs resulted in a greater reduction in canine malignant cell proliferation than either treatment alone. SB injection did not affect the viability of peripheral blood mononuclear cells regardless of concentration, which suggested that SB injection did not suppress the activity of normal cells. This study suggested that SB injection can be considered an effective alternative medication for animal cancers in veterinary medicine.
Keywords: Antitumor agent; Canine melanoma; Canine osteosarcoma; Natural extract.