A Sanguinarine Analogue Targeting ROS Signaling Exhibits Anti-Tumour Effects by Inducing Apoptosis and Ferroptosis in...

Osteosarcoma is a common malignant bone tissue tumour that frequently occurs in the adolescent population, with recurrence and metastasis rates that remain high under current treatment strategies, necessitating the development of cost-effective and efficient anti-osteosarcoma drugs. Sanguinarine, a benzophenanthridine alkaloid derived from plants in the Papaveraceae family, possesses anti-tumour capabilities; however, its clinical application is limited due to poor water solubility and potential organ toxicity. Through screening 30 sanguinarine analogues, in this study we found that analogue 25 exhibited significant activity and could suppress cell proliferation and arrest the cell cycle at the G0/G1 phase in U2OS and MG63 cells, with IC₅₀ values of 1.484 and 1.954 μM, respectively. Analogue 25 could also induce cell apoptosis by increasing the levels of cleaved caspase-9 and BAX. Subsequently, we demonstrated that analogue 25 increased the ROS level, decreased the mitochondrial membrane potential, and increased lipid peroxidation in osteosarcoma cells. After reducing ROS levels through NAC, analogue 25 was able to regulate mitochondrial-mediated osteosarcoma cell apoptosis by modulating the ROS level. Furthermore, analogue 25 could also regulate the expression of ferroptosis-related proteins (including GPX4, SLC7A11 and PTGS2) through the NRF2/GPX4 pathway, ultimately leading to the accumulation of lipid peroxidation and ferroptosis. In a xenograft mouse tumour model derived from osteosarcoma cell lines, analogue 25 exhibited stronger anti-tumour activity than sanguinarine by regulating apoptosis and ferroptosis without causing liver or kidney toxicity. These findings highlight that sanguinarine analogue 25 has beneficial effects in treating osteosarcoma.