This approach did not reveal As2O3-associated toxicity, indicating that arsenene-basednanotherapeutic could be employed to amplify the response rate ofanti-PD-1/anti-PD-L1 therapy to improve the clinical outcomes of HCCpatients and potentially other solid tumors (e.g., breast cancer)that are refractory to anti-PD-1/anti-PD-L1 therapy. Here, CD274 is linked to breast cancer.