Hypoxia-responsive Immunostimulatory Nanomedicines Synergize with Checkpoint Blockade Immunotherapy for Potentiating Cancer Immunotherapy

Chem Eng J. 2023 Jan;451(Pt 2):138781. doi: 10.1016/j.cej.2022.138781. Epub 2022 Aug 24.

Abstract

Inducing cell death while simultaneously enhancing antitumor immune responses is a promising therapeutic approach for multiple cancers. Celastrol (Cel) and 7-ethyl-10-hydroxycamptothecin (SN38) have contrasting physicochemical properties, but strong synergy in immunogenic cell death induction and anticancer activity. Herein, a hypoxia-sensitive nanosystem (CS@TAP) was designed to demonstrate effective immunotherapy for colorectal cancer by systemic delivery of an immunostimulatory chemotherapy combination. Furthermore, the combination of CS@TAP with anti-PD-L1 mAb (αPD-L1) exhibited a significant therapeutic benefit of delaying tumor growth and increased local doses of immunogenic signaling and T-cell infiltration, ultimately extending survival. We conclude that CS@TAP is an effective inducer of immunogenic cell death (ICD) in cancer immunotherapy. Therefore, this study provides an encouraging strategy to synergistically induce immunogenic cell death to enhance tumor cytotoxic T lymphocytes (CTLs) infiltration for anticancer immunotherapy.

Keywords: Cancer immunotherapy; Covalent organic frameworks; Immunogenic cell death; Immunogenic nanomedicine.