Ropivacaine and lidocaine inhibit SaOS-2 osteosarcoma cell proliferation and invasion via mitochondrial dysfunction and apoptosis.

Local anesthetics are routinely used for pain management, yet their broader effects on cancer cells remain incompletely understood. Here, we investigate the impact of ropivacaine hydrochloride and lidocaine hydrochloride monohydrate on SaOS-2 human osteosarcoma cells using a series of in vitro assays. Our findings indicate that both anesthetics markedly reduce cell viability and proliferation, as measured by XTT and Colony formation assays, respectively. Mechanistic studies reveal significant disruption of mitochondrial function, evidenced by decreased membrane potential, enhanced mitochondrial superoxide production, and pronounced mitochondrial fragmentation. Concurrently, the expression of matrix metalloproteinases (MMP-2 and MMP-9) is downregulated, while pro-apoptotic markers (Caspase-3, Caspase-9, and BAX) are upregulated. Neither agent alters Vimentin or E-cadherin expression, suggesting a limited effect on epithelial-mesenchymal transition pathways. Notably, lidocaine and ropivacaine also inhibit SaOS-2 cell migration and invasion, as demonstrated by Scratch, single-cell migration, and Transwell invasion assays. Furthermore, both agents suppress alkaline phosphatase activity, a hallmark associated with osteosarcoma differentiation and metastatic potential. Taken together, these results support the conclusion that ropivacaine and lidocaine exert broad anti-tumor effects by impairing both mitochondrial homeostasis and the invasive phenotype in osteosarcoma cells. Their capacity to mitigate core hallmarks of malignancy underscores the need for further investigation into local anesthetics as potential adjuvant therapies for osteosarcoma.