Dual depletion of myeloid-derived suppressor cells and tumor cells with self-assembled gemcitabine-celecoxib nano-twin drug for cancer chemoimmunotherapy.

Myeloid-derived suppressor cells (MDSCs) have played a significant role in facilitating tumor immune escape and inducing an immunosuppressive tumor microenvironment. Eliminating MDSCs and tumor cells remains a major challenge in cancer immunotherapy. A novel approach has been developed using gemcitabine-celecoxib twin drug-based nano-assembled carrier-free nanoparticles (GEM-CXB NPs) for dual depletion of MDSCs and tumor cells in breast cancer chemoimmunotherapy. The GEM-CXB NPs exhibit prolonged blood circulation, leading to the preferential accumulation and co-release of GEM and CXB in tumors. This promotes synergistic chemotherapeutic activity by the proliferation inhibition and apoptosis induction against 4T1 tumor cells. In addition, it enhances tumor immunogenicity by immunogenic cell death induction and MDSC-induced immunosuppression alleviation through the depletion of MDSCs. These mechanisms synergistically activate the antitumor immune function of cytotoxic T cells and natural killer cells, inhibit the proliferation of regulatory T cells, and promote the M2 to M1 phenotype repolarization of tumor-associated macrophages, considerably enhancing the overall antitumor and anti-metastasis efficacy in BALB/c mice bearing 4T1 tumors. The simplified engineering of GEM-CXB NPs, with their dual depletion strategy targeting immunosuppressive cells and tumor cells, represents an advanced concept in cancer chemoimmunotherapy.

Tumor Microenvironment Sequential Drug/Gene Delivery Nanosystem for Realizing Multistage Boosting of Cancer-Immunity Cycle on Cancer Immunotherapy.

The antitumor immune response of cancer immunotherapy is a cascade of cancer-immunity cycles (CIC). The immunosuppression of the tumor microenvironment and low immunogenicity of tumor cells, insufficient T lymphocyte activation, trafficking, and infiltration caused the failure to initiate and run the continuous multistage CIC, leading to unsatisfactory cancer immunotherapy outcomes. A doxorubicin/interleukin-12 plasmid DNA/celecoxib (DOX/pIL-12/CXB) combination strategy was designed by targeting the cascade CIC. Then, an intratumoral CXB-detachable nanosystem, or DOX/PAC/pIL-12 micelleplexes, was developed for sequential drug/gene delivery to facilitate the multistage boosting of CIC on synergistic cancer immunotherapy. The DOX/PAC/pIL-12 micelleplexes could program intratumorally sequential release of CXB to remodulate the tumor microenvironment immunosuppression by suppressing the cyclooxygenase-2/prostaglandin E2 (COX-2/PGE2) pathway. The smaller sizes and surface charge-switched micelleplexes facilitated the codelivery and corelease of DOX and pIL-12 inside 4T1 tumor cells. These micelleplexes exerted a synergistic antitumor immune response using CIC cascade activation and amplification, providing therapeutic antitumor and antimetastasis efficacy. The drug/gene sequential delivery nanosystem provides a complete CIC-boosted combinatory strategy for developing immunotherapy against cancer.

An ROS-responsive artesunate prodrug nanosystem co-delivers dexamethasone for rheumatoid arthritis treatment through the HIF-1α/NF-κB cascade regulation of ROS scavenging and macrophage repolarization.

The signaling cascade between nuclear factor-kappa B (NF-κB) and hypoxia-inducible factor-1α (HIF-1α) can be activated by proinflammatory M1 macrophages in rheumatoid arthritis (RA), which produces reactive oxygen species (ROS) and enhances M1 macrophage polarization, thus aggravating the development of RA. Therefore, an ROS-responsive artesunate prodrug micellar nanosystem for co-delivery of dexamethasone (DEX/HA-TK-ART micelles, abbreviated as DEX/HTA) was developed for synergistic inhibition of the HIF-1α/NF-κB cascade to regulate ROS scavenging and macrophage repolarization in RA combination therapy. DEX/HTA micelles displayed prolonged circulation in blood and efficiently co-delivered ART&DEX in the inflamed joints of adjuvant-induced arthritis (AIA) rats; moreover, they were specifically recognized and internalized into M1 macrophages through CD44 receptor-mediated endocytosis. ROS-responsive co-released ART&DEX then exerted a synergistic action to efficiently perform ROS scavenging and repolarization of M1 to M2 macrophages by inhibition of the HIF-1α/NF-κB cascade. The intravenous administration of DEX/HTA micelles into AIA rat models significantly alleviated inflammatory cell infiltration and repaired cartilage injury in the joint. Collectively, our study highlights the therapeutic potential of DEX/HTA micelles for treating RA through synergistic inhibition of the HIF-1α/NF-κB signaling cascade to regulate ROS scavenging and macrophage repolarization. STATEMENT OF SIGNIFICANCE: An ROS-responsive artesunate (ART) prodrug micellar nanosystem for co-delivering dexamethasone (DEX), abbreviated as DEX/HA-TK-ART micelle, was developed for synergistic cascade regulation of the HIF-1α/NF-κB pathway on ROS scavenging and macrophage repolarization in combination therapy for rheumatoid arthritis. The well-designed nanosystem showed prolonged circulation in blood and superior ART&DEX accumulation in the inflamed joints of AIA rats; moreover, the micelles were specifically internalized into M1 macrophages and co-released ART&DEX, subsequently leading to inhibition of the HIF-1α/NF-κB pathway for ROS scavenging and macrophage repolarization, thus generating synergistic anti-inflammatory effects in RAW 264.7 cells and AIA rats. The HIF-1α/NF-κB cascade regulation on ROS scavenging and macrophage repolarization based on ART&DEX combination with smart nanotechnology could serve as a promising approach for rheumatoid arthritis therapy.

Collagenase-I decorated co-delivery micelles potentiate extracellular matrix degradation and hepatic stellate cell targeting for liver fibrosis therapy.

Liver fibrosis is a pathological process of multiple chronic liver diseases progressing to cirrhosis for which there are currently no effective treatment options. During fibrosis progression, the overproduction of extracellular matrix (ECM) collagen secreted by hepatic stellate cells (HSCs) greatly impedes drug delivery and reduces drug therapeutic effects. In this study, a glycyrrhetinic acid (GA)-conjugated prodrug micellar system with collagenase I (COL) decoration (COL-HA-GA, abbreviated as CHG) was designed to codelivery sorafenib (Sora/CHG, abbreviated as S/CHG) for potentiating ECM degradation and HSCs targeting on liver fibrosis therapy. In ECM barrier models established in vitro or in vivo, CHG micelles efficiently degraded pericellular collagen and demonstrated enormous ECM penetration abilities as well as superior HSCs internalization. Moreover, CHG micelles exhibited more Sora & GA accumulations and activated HSCs targeting efficiencies in the fibrotic livers than those in the normal livers. More importantly, S/CHG micelles were more effective in anti-liver fibrosis by lowering the collagen content, inhibiting the HSCs activation, as well as down-regulating the fibrosis-related factors, leading to reverse the fibrotic liver to normal liver through the multi-mechanisms including angiogenesis reduction, liver fibrosis microenvironment regulation, and epithelial-mesenchymal transition inhibition. In conclusion, the developed COL decorated nano-codelivery system with fibrotic ECM collagen degradation and activated HSCs targeting dual-functions exhibited great potential for liver fibrosis therapy. STATEMENT OF SIGNIFICANCE: A glycyrrhetinic acid (GA)-conjugated prodrug with collagenase I (COL) decoration (CHG) was designed for codelivery with sorafenib (S/CHG), potentiating extracellular matrix (ECM) degradation-penetration and hepatic stellate cells (HSCs) targeting on liver fibrosis therapy. In ECM barrier models, CHG micelles efficiently degraded pericellular collagen and demonstrated ECM penetration abilities, as well as displayed superior HSCs internalization. Moreover, S/CHG micelles were more effective in anti-liver fibrosis by lowering the collagen content, inhibiting the HSCs activation, as well as down-regulating cytokines, reversing the fibrotic liver to normal through various mechanisms. In conclusion, the developed fibrotic ECM degradation and HSCs targeting dual-functional nano-codelivery system provided a prospective potentiality in liver fibrosis therapy.

Crizotinib prodrug micelles co-delivered doxorubicin for synergistic immunogenic cell death induction on breast cancer chemo-immunotherapy.

Chemotherapeutic agents can trigger the immune response via inducing immunogenic cell death (ICD), but the weak ICD effect induced by chemotherapy alone limits its lasting antitumor immunotherapy effect. A Cro polymerized prodrug carriers (POEG-b-PCro) with immunostimulatory by ICD induction was developed and co-delivered DOX to generate synergistic ICD induction for chemo-immunotherapy on breast cancer. DOX/POEG-b-PCro micelles displayed prolonged circulation in blood, efficient accumulation in tumors, internalization and then co-released DOX&Cro in tumor cells. Moreover, the DOX/POEG-b-PCro micelles synergistically triggered ICD induction by releasing the nuclear high mobility group box 1 (HMGB1) and down-regulation of c-Met level for generating chemo-immune anti-tumor actions. Importantly, the DOX/POEG-b-PCro micelles synergistically enhanced the tumor cytotoxic T lymphocytes infiltration, concomitant decreasing the immunosuppressive regulatory T (Treg) cells, accompanied with the increased cytokines secretion of IFN-γ and TNF-α, consequently displaying an improved anti-tumor activity in 4 T1 breast cancer mice. Overall, POEG-b-PCro prodrug micelles co-delivered DOX could be served as a promising nano drug delivery system for synergistic ICD induction on breast cancer chemo-immunotherapy.

The therapeutic efficacy and safety improvements of crizotinib prodrug micelles on breast cancer treatment.

Nowadays, breast cancer has become a major killer threatening women's health. MET is a receptor tyrosine kinase that upon binding of its ligand, hepatocyte growth factor, activates downstream pathways with diverse cellular functions which are important in the occurrence and development of breast cancer. Crizotinib (Cro) is a multi-target tyrosine kinase inhibitor targeting ALK gene recombination, MET gene amplification and ROS gene. Although Cro has the ideal treatment for breast cancer, Cro has stronger hepatotoxicity and lacks targeting capacity to the tumor cell, which limited Cro to effectively therapy breast cancer. In this study, we develop a novel prodrug micelle through polymerization reaction polymerizing Cro onto the chain to form POEG-b-PCro prodrug micelles, in which the drug loading capacity of Cro was significantly increased to improve the cumulant of the tumor. Pharmacokinetic and biodistribution studies illustrated that POEG-b-PCro prodrug micelles had a significant effect by improving Cro content in the tumor. Meanwhile, the antitumor mechanism of POEG-b-PCro prodrug micelles proved that POEG-b-PCro prodrug micelles had a stronger effect by reducing negative regulatory proteins. POEG-b-PCro prodrug micelles had splendid safety through safety study in vivo to account for POEG-b-PCro prodrug micelles. Therefore, POEG-b-PCro prodrug micelles are a promising drug delivery strategy for reducing toxicity and enhancing the efficacy of Cro.

Combination therapy based on targeted nano drug co-delivery systems for liver fibrosis treatment: a review.

Liver fibrosis is the hallmark of liver disease and occurs prior to the stages of cirrhosis and hepatocellular carcinoma. Any type of liver damage or inflammation can result in fibrosis. Fibrosis does not develop overnight, but rather as a result of the long-term action of injury factors. At present, however, there are no good treatment methods or specific drugs other than removing the pathogenic factors. Drug application is still limited, which means that drugs with good performance in vitro cannot achieve good therapeutic effects in vivo, owing to various factors such as poor drug targeting, large side effects and strong hydrophobicity. Hepatic stellate cells (HSCs) are the primary effector cells in liver fibrosis. The nano-drug delivery system is a new and safe drug delivery system that has many advantages which are widely used in the field of liver fibrosis. Drug resistance and side effects can be reduced when two or more drugs are used in combination drug delivery. Combination therapy of drugs with different targets has emerged as a novel approach to treating liver fibrosis, and the nano co-delivery system enhances the benefits of combination therapy. While nano co-delivery systems can maximise benefits while avoiding drug side effects, this is precisely the advantage of the nano co-delivery system. This review briefly described the pathogenesis and current treatment strategies, the different co-delivery systems of combination drugs in the nano delivery system, and targeting strategies for nano delivery systems on liver fibrosis therapy. Due to their superior performance, nano delivery systems and targeting drug delivery systems have received a lot of attention in the new drug delivery system. The new delivery systems offer a new pathway in the treatment of liver fibrosis, and it is believed that it can be a new treatment for fibrosis in the future. Nano co-delivery system of combination drugs and targeting strategies has proven the effectiveness of anti-fibrosis at the experimental level.

Nano drug delivery system reconstruct tumour vasculature for the tumour vascular normalisation.

The abnormal structure and function of blood vessels in the TME are obvious characteristics of the tumour. Abnormal blood vessels with high leakage support the occurrence of malignant tumours and increase the possibility of tumour cell invasion and metastasis. The formation of abnormal vascular also enhances immunosuppression and prevents the delivery of chemotherapy drugs to deeper tumours. Therefore, the normalisation of tumour blood vessels is a very promising approach to improve anti-tumour efficacy, aiming to restore the structural integrity of vessels and improve drug delivery efficiency and anti-tumour immunity. In this review, we have summarised strategies to improve cancer treatment that via nano drug delivery technology regulates the normalisation of tumour blood vessels. The treatment strategies related to the structure and function of tumour blood vessels such as angiogenesis factors, tumour-associated macrophages, tumour vascular endothelial cells, tumour-associated fibroblasts and immune checkpoints in the TME were mainly discussed. The normalisation of tumour blood vessels presents new opportunities and challenges for the more efficient delivery of nanoparticles to tumour tissues and cells and an innovative combination of treatments for cancer.

Tumor Microenvironment-Triggered Charge Reversal Polymetformin-Based Nanosystem Co-Delivered Doxorubicin and IL-12 Cytokine Gene for Chemo-Gene Combination Therapy on Metastatic Breast Cancer.

Cancer metastasis is the leading cause of high mortality and disease recurrence in breast cancer. In this study, a novel tumor microenvironment charge reversal polymetformin (PMet)-based nanosystem co-delivering doxorubicin (DOX) and plasmid encoding IL-12 gene (pIL-12) was developed for chemo-gene combination therapy on metastatic breast cancer. Cationic PMet was readily self-assembled into micelles for DOX physical encapsulation and pIL-12 complexation, and a hyaluronidase-sensitive thiolated hyaluronic acid (HA-SH) was then collaboratively assembled to the pIL-12/DOX-PMet micelleplexes, abbreviated as HA/pIL-12/DOX-PMet. DOX/pIL-12 loaded in HA/pIL-12/DOX-PMet micelleplexes presented prolonged circulation in blood, efficient accumulation in tumors, and internalization in tumor cells via CD44 receptor-mediated tumor specific-targeting, and DOX/pIL-12 was co-released in endo/lysosomes tumor microenvironment followed by HAase-triggered HA-SH deshielding from HA/pIL-12/DOX-PMet micelleplexes. Moreover, HA/PMet micelleplexes displayed excellent pIL-12 transfection and IL-12 expression in tumors of 4T1 tumor-bearing mice. Importantly, HA/pIL-12/DOX-PMet micelleplexes synergistically enhanced the NK cells and tumor infiltrated cytotoxic T lymphocytes and modulated the polarization from protumor M2 macrophages to activated antitumor M1 macrophages, with concomitant decreasing of the immunosuppressive regulatory T (Treg) cells, accompanied by an increase in the cytokines expression of IL-12, IFN-γ and TNF-α, consequently showing an improved antitumor and antimetastasis activity in 4T1 breast cancer lung metastasis mice model. In conclusion, the tumor microenvironment charge reversal HA/PMet nanosystem holds great promise for DOX/pIL-12 co-delivery and exploitation in chemo-gene combination therapy on metastatic breast cancer.

Codelivered Chemotherapeutic Doxorubicin via a Dual-Functional Immunostimulatory Polymeric Prodrug for Breast Cancer Immunochemotherapy.

Immunochemotherapy is viewed as a promising approach for cancer therapy via combination treatment with immune-modulating drugs and chemotherapeutic drugs. A novel dual-functional immunostimulatory polymeric prodrug carrier PEG2k-Fmoc-1-MT was developed for simultaneously delivering 1-methyl tryptophan (1-MT) of an indoleamine 2,3-dioxygenase (IDO) inhibitor and chemotherapeutic doxorubicin (DOX) for breast cancer immunochemotherapy. DOX/PEG2k-Fmoc-1-MT micelles were more effective in cell proliferation inhibition and apoptosis induction in 4T1 cells. PEG2k-Fmoc-1-MT prodrug micelles presented enhanced inhibition ability of IDO with decreased kynurenine production and increased the proliferation in dose-dependent manners of effector CD4+ and CD8+ T cells. DOX/PEG2k-Fmoc-1-MT micelles exhibited prolonged blood circulation time and superior accumulation of DOX and 1-MT in tumors compared to that of DOX and 1-MT solutions. A significantly enhanced immune response of the DOX/PEG2k-Fmoc-1-MT micelles was observed with the decreasing tryptophan/kynurenine ratio in blood and tumor tissue, promoting effector CD4+ and CD8+ T cells while reducing regulatory T cell (Tregs) expression. Meanwhile, the coreleased DOX-triggered immunogenic cell death action combined with the cleaved 1-MT promoted the related cytokine secretion of tumor necrosis factor-α, interleukin-2, and interferon-γ, further facilitating the T cell-mediated immune responses. More importantly, the DOX-loaded micelles led to a significantly improved inhibition on tumor growth and prolonged animal survival rate in a 4T1 murine breast cancer model. In conclusion, DOX codelivered by a PEG2k-Fmoc-1-MT immunostimulatory polymeric prodrug showed a maximum immunochemotherapy efficacy against breast cancer.