Transforming Cancer-Associated Fibroblast Barrier into Drug Depots to Boost Chemo-Immunotherapy in "Shooting Fish in a Barrel" Pattern

Unlocking the power of immunotherapy: Combinatorial delivery of plasmid IL-15 and gemcitabine to synergistically remodeling the tumor microenvironment

Cancer immunotherapy has emerged as a promising clinical treatment strategy in recent years. Unfortunately, the satisfactory antitumor therapeutic efficacy of immunotherapy is limited by intricate immunosuppressive tumor microenvironment (ITM). To remodel the ITM and alleviate the immune evasion, we constructed FA-PEG-modified liposomes to deliver plasmid IL-15 (pIL-15) and gemcitabine (GEM) (FPCL@pIL-15 + FPGL), respectively. The FPCL@pIL-15 (150 nm) and FPGL (120 nm) exhibited symmetrically spherical structures as well as desirable penetration and accumulation on tumor tissue depending on folic acid (FA) specialized targeting function. The transfected expression of IL-15 efficiently fosters the proliferation and co-activation of Natural killer (NK) cells and CD8+T cells through binding to IL-15R. FPGL upregulated the expression of Natural killer group 2 member D ligands (NKG2DLs) and reinforced recognition by NK cells to alleviate the immune evasion, and simultaneously promoted activation of CD8+T cells through immunogenic cell death (ICD) effects. More importantly, the combinatorial administration achieved intended anti-tumor efficacy in the subcutaneous 4T1 tumor model. In essence, we demonstrated that combining FPCL@pIL-15 with FPGL synergistically stimulates and mobilizes the immune system to reverse the ITM and trigger an anti-tumor immune response, indicating a tremendous potential for application in immunotherapy.

An exosomal strategy for targeting cancer-associated fibroblasts mediated tumors desmoplastic microenvironments

Tumors desmoplastic microenvironments are characterized by abundant stromal cells and extracellular matrix (ECM) deposition. Cancer-associated fibroblasts (CAFs), as the most abundant of all stromal cells, play significant role in mediating microenvironments, which not only remodel ECM to establish unique pathological barriers to hinder drug delivery in desmoplastic tumors, but also talk with immune cells and cancer cells to promote immunosuppression and cancer stem cells-mediated drug resistance. Thus, CAFs mediated desmoplastic microenvironments will be emerging as promising strategy to treat desmoplastic tumors. However, due to the complexity of microenvironments and the heterogeneity of CAFs in such tumors, an effective deliver system should be fully considered when designing the strategy of targeting CAFs mediated microenvironments. Engineered exosomes own powerful intercellular communication, cargoes delivery, penetration and targeted property of desired sites, which endow them with powerful theranostic potential in desmoplastic tumors. Here, we illustrate the significance of CAFs in tumors desmoplastic microenvironments and the theranostic potential of engineered exosomes targeting CAFs mediated desmoplastic microenvironments in next generation personalized nano-drugs development.

Perylene-Mediated Cytoskeletal Dysfunction Remodels Cancer-Associated Fibroblasts to Augment Antitumor Immunotherapy

Targeted reprogramming of cancer-associated fibroblasts (CAFs) is one of the most essential cancer therapies. However, how to reprogram active CAFs toward deactivated state still remains immense challenge. To tackle this challenge, herein, one perylene N, N'-bis(2-((dimethylammonium)ethylene)-2-(methoxylethyl))-1, 6, 7, 12-tetrachloroperylene-3, 4, 9, 10-tetracarboxylic diimide (PDIC-OC) is prepared, which can trigger endogenous reactive oxygen species (ROS) burst to result in cytoskeletal dysfunction and cell apoptosis so that suppress transforming growth factor β (TGF-β) production. As a result, PDIC-OC can reprogram the activated CAFs and relieve immunosuppressive tumor microenvironment by efficient polarization of M2-typed macrophages into M1-typed ones, downregulation of alpha-smooth muscle actin (α-SMA), alleviation of hypoxic state to promote infiltration of cytotoxic T lymphocytes, and ultimately realizes outstanding antitumor performance on B16F10 tumor-xenografted and lung-metastatic mouse model even at low concentration of 1 mg kg-1 body weight. This work thus presents a novel strategy that cytoskeleton dysfunction and cell apoptosis cooperatively suppress the secretion of TGF-β to reprogram CAFs and meanwhile clarifies intrinsic mechanism for perylene-triggered chemo-immunotherapy against hypoxic tumors.