CSF2 and neoplasm: To determine whether the combination of GM-CSF and Bif@PAu-NPs-based PTT can induce long-term immune memory, we established secondary tumors as outlined in Fig. 8A. Briefly, the tumor-bearing mice were treated with NS, Bif@PAu-NPs, Bif@PAu-NPs + NIR and Bif@PAu-NPs + NIR + GM-CSF, and re-injected with CT-26 cells into their contralateral side 60 days after starting the treatment.