Combination Nanodrug Delivery Systems Facilitate the Syncretism of Chemotherapy with Immunotherapy to Promote Cancer Treatment.

Cancer has emerged as a significant threat that gravely endanger human health. Anti-tumor immunotherapy has now emerged as an important treatment for cancer. However, immunosuppressive tumor microenvironment limits the antitumor immunity. The importance of the immune system in the cancer treatment process must be emphasized. Herein, two precision-targeted nanoparticles PD-L1@Cur-NPs and PD-1@AS-NPs are constructed for cancer treatment. PD-L1@Cur-NPs can precisely target tumor cells in vivo to eradicate tumor cells or induce them apoptosis. PD-1@AS-NPs can precisely target T cells in vivo to activate the T cell-mediated immune system and induce antitumor immune responses. Furthermore, these two nanoparticles have good synergistic effect and show stronger antitumor effect after combination. After treatment with the combination of two nanoparticles, the tumor volumes of C57BL/6 tumor-bearing mice are significantly reduced. Moreover, the percentage of CD8⁺T cells and CD4⁺T cells in the tumor significantly increased, and the percentage of regulatory T cells significantly decreased. The percentage of memory T cells and memory effector T cells in the spleen also significantly increased after treatment, suggesting that the antitumor immunity is activated after treatment. This study provides a new antitumor treatment strategy combining chemotherapy and immunotherapy, which has good application prospect.