Fig 2: Heat treatment accelerated the growth of the tumor margin beyond PTT. A) The depth of effective PTT. Above 43 °C, tumor cell can be effectively suppressed. B) Tumor volume of the mice treated with saline and with PTT (partially treated). C) Protein characterization of 4T1 cells with different heat treatments (treated with heat for 5 min then cultured with different times). D) Proportion of variation of HSP90 and HSP70 after different heat treatments. E) Proportion variation of IDO and PD-L1 after different heat treatments. F) Tumor volume of the mice implanted with normal 4T1 cells and preheated 4T1 cells (42 °C for 5 min, then cultured for another 24 h before implantation). G,H) The images of IHC analysis performed on representative subsets of the tumors (G, IDO; H, PD-L1, tumor tissues were obtained after the experiment in Figure 1F was completed). Magnification: 20×. The results of ICH analysis further proved the upregulation of IDO and PD-L1 in the tumor tissues in which the tumor cells were preheated before the implantation.

Fig 3: Passive tumor targeting of NLG919/IR780 micelles and suppression of the growth of the tumor margin beyond PTT. A) Fluorescence images of MCF‐7 breast cancer‐bearing balb/C‐nu mice treated with saline, free IR780, and NLG919/IR780 micelles. B) The fluorescence intensity of tumors versus time. Saline, free IR780, and NLG919/IR780 micelles were injected intravenously. C) The administration route of NLG919/IR780 micelles to evaluate the growth inhibition mediated by PTT and IDO inhibition to the tumor margin beyond PTT. D) Tumor volume of the mice with different treatments. E) Mean survival of the mice with different treatments.

Fig 4: IDO activity inhibition mediated by NLG919 micelles and growth inhibition of tumor cells cotreated with IDO inhibition and PTT. A,B) IDO and PD‐L1 expression of different cell types. C) 293T cell survival after coculturing with NLG919 micelles with or without IDO gene transfection. D) MCF‐7 cell survival after coculturing with NLG919 micelles with or without IDO gene transfection. E,F) Effect of NLG919 micelles on the expression of IDO after treatment. G) MCF‐7 cell survival after coculturing with NLG919/IR780 micelles with or without laser irradiation (without IDO transfection). H) MCF‐7 cell survival after coculturing with NLG919/IR780 micelles with or without laser irradiation (with IDO transfection).