Sulfasalazine-loaded nanoframes: A new frontier in bladder cancer therapy through ferroptosis induction

Promoting ferroptosis in tumor cells has emerged as a promising strategy for cancer therapy. Nonetheless, the heightened antioxidant activity within tumor cells hampers this approach, diminishing its effectiveness and fostering drug resistance. In this study, a new type of sulfasalazine (SAS) loaded nanoframe self-etched Pt-Co nanodendrites (Pt/Co-BNN@SAS) was developed, presenting a novel avenue for inducing ferroptosis in tumor cells by depleting glutathione (GSH) for cancer treatment. Pt/Co-BNN exhibits notable peroxidase (POD) activity, catalyzing the production of abundant oxygen radicals through the consumption of hydrogen peroxide (H₂O₂) and the concurrent depletion of GSH. Simultaneously, the liberated sulfasalazine (SAS) from Pt/Co-BNN@SAS effectively obstructs system xc^-, impeding the absorption of cystine by tumor cells and thereby expediting GSH depletion. The expeditious reduction of GSH markedly stimulates the accumulation of lipid peroxides (LPO) and suppresses glutathione peroxidase 4 (GPX4), consequently triggering ferroptosis in bladder cancer cells and inhibiting the migration ability of bladder cancer cells effectively. This research contributes to a more profound comprehension of nano-drug-biological interactions and provides a prospective outlook on treating bladder cancer by instigating ferroptosis in tumor cells through GSH depletion.