PDCD1 and melanoma: The low toxicity results from the rapid clearance of nanoparticles from normal organs and reduced propensity to aggregate that was highly associated with its toxicity and ameliorated therapeutic efficacy.42 Additionally, our results proved that nanoparticle delivery of miR-21–3 p could sensitize melanoma cells to anti-PD-1 immunotherapy by facilitating ferroptosis, highlighting it as a novel therapeutic approach to synergize with immunotherapy.