Combined Auranofin and Celecoxib Suppresses the Local Progression and Pulmonary Metastases of Osteosarcoma In Vivo

Background/Aim: Osteosarcoma (OS) is a rare malignant tumor with a poor survival rate. Our previous study reported that auranofin (AUR), a thioredoxin reductase inhibitor, suppresses OS pulmonary metastases; however, the local progression of OS is not affected, in vivo. Nonetheless, the development of augmentation therapy with AUR to inhibit OS local progression remains challenging. Celecoxib (CE), an anti-inflammatory drug, potently enhances the therapeutic activity of AUR against colon cancer. Consequently, this study investigated the combined effects of AUR and CE on OS local progression and pulmonary metastases, in vivo. Materials and Methods: C3H/HeSlc mice were implanted with the murine OS cell line, LM8. The mice were treated either with a vehicle control, AUR, or combination of AUR and CE (AUR-CE). The primary tumor size and weight were evaluated for the study duration and at resection, respectively. Hematoxylin and eosin and Ki-67 staining were performed to evaluate OS local progression and pulmonary metastases. Results: Mice in the AUR-CE group showed statistically significantly suppressed tumor sizes and weights at the time of excision compared with those in the vehicle. The mice in the AUR group did not show a statistically significant effect. Histopathological analysis of the primary tumor revealed a statistically significant decrease of the Ki-67-positive cells in the AUR-CE group compared with the vehicle group. Histopathological and quantitative analyses demonstrated that the AUR and AUR-CE groups had statistically significant reductions in the development of OS pulmonary metastases compared with the vehicle group. Conclusion: The combination of AUR and CE significantly inhibited OS local progression and pulmonary metastases.