Fig. 4.

Targeted strategies to maximize the efficacy and minimize the adverse effects of pro-oxidant anti-cancer therapy. a. To maximize the killing effect of OS and reduce the side effects related to oxidative damage, improving the targeting of drugs is a balanced approach. Recently, rapid progress has been made in encapsulating pro-oxidants with specific materials to make nanoscale particles. Due to the appropriate particle size or some special targeting recognition capabilities, nanoparticles can target and enrich cancer sites, or even subcellular structures of cancer cells such as cell membranes and mitochondria. b. For drug resistance considerations, targeting the phenotypic signal transduction pathways of CSCs is a wise choice to overcome resistance. The activation of some highly conserved signal transduction pathways may be involved in the phenotype of CSCs, including Notch, Hedgehog, and WNT pathways, and corresponding inhibitors have also successively shown the hope of overcoming the resistance of CSCs.