Peritoneal carcinomatosis (PC) has an extremely poor prognosis, which leads to a significantly decreased overall survival in patients with peritoneal implantation of
cancer cells. Administration of
sodium selenite by
intraperitoneal injection is highly effective in inhibiting PC. Our previous study found that
selenium nanoparticles (SeNPs) have higher redox activity and safety than
sodium selenite. In the present study, we examined the
therapeutic effect of SeNPs on PC and elucidated the potential mechanism. Our results revealed that intraperitoneal delivery of SeNPs to
cancer cells in the peritoneal cavity of mice at a tolerable dose was beneficial for prolonging the survival time of mice, even better than the optimal dose of
cisplatin. The underlying mechanism involved in
SeNP-induced
reactive oxygen species (ROS) production caused protein degradation and apoptotic response in
cancer cells. Interestingly,
N-acetyl-l-cysteine (NAC), recognized as a ROS scavenger, without reducing the efficacy of SeNPs, enhanced ROS production and cytotoxicity. The effect of NAC was associated with the following mechanisms: (1) the
thiol groups in NAC can increase the biosynthesis of endogenous
glutathione (GSH), thus increasing the production of
SeNP-induced ROS and cytotoxicity and (2) redox cycling of SeNPs was directly driven by
thiol groups in NAC to produce ROS. Moreover, NAC, without increasing the systematic toxicity of SeNPs, decreased
SeNP-induced lethality in healthy mice. Overall, we demonstrated that SeNPs exert a potential cytotoxicity effect by inducing ROS production in
cancer cells; NAC effectively heightens the property of SeNPs in vitro and in vivo.