Vicious Cycle-Breaking Lipid Nanoparticles Remodeling Multicellular Crosstalk to Reverse Liver Fibrosis.

During liver fibrogenesis, the reciprocal crosstalk among capillarized liver sinusoidal endothelial cells (LSECs), activated hepatic stellate cells (HSCs), and dysfunctional hepatocytes constructs a self-amplifying vicious cycle, greatly exacerbating the disease condition and weakening therapeutic effect. Limited by the malignant cellular interactions, the previous single-cell centric treatment approaches show unsatisfactory efficacy and fail to meet clinical demand. Herein, a vicious cycle-breaking strategy is proposed to target and repair pathological cells separately to terminate the malignant progression of liver fibrosis. Chondroitin sulfate-modified and vismodegib-loaded nanoparticles (CS-NPs/VDG) are designed to efficiently normalize the fenestrae phenotype of LSECs and restore HSCs to quiescent state by inhibiting Hedgehog signaling pathway. In addition, glycyrrhetinic acid-modified and silybin-loaded nanoparticles (GA-NPs/SIB) are prepared to restore hepatocytes function by relieving oxidative stress. The results show successful interruption of vicious cycle as well as distinct fibrosis resolution in two animal models through multiregulation of the pathological cells. This work not only highlights the significance of modulating cellular crosstalk but also provides a promising avenue for developing antifibrotic regimens.

Engineered stem cell-based strategy: A new paradigm of next-generation stem cell product in regenerative medicine.

Stem cells have garnered significant attention in regenerative medicine owing to their abilities of multi-directional differentiation and self-renewal. Despite these encouraging results, the market for stem cell products yields limited, which is largely due to the challenges faced to the safety and viability of stem cells in vivo. Besides, the fate of cells re-infusion into the body unknown is also a major obstacle to stem cell therapy. Actually, both the functional protection and the fate tracking of stem cells are essential in tissue homeostasis, repair, and regeneration. Recent studies have utilized cell engineering techniques to modify stem cells for enhancing their treatment efficiency or imparting them with novel biological capabilities, in which advances demonstrate the immense potential of engineered cell therapy. In this review, we proposed that the "engineered stem cells" are expected to represent the next generation of stem cell therapies and reviewed recent progress in this area. We also discussed potential applications of engineered stem cells and highlighted the most common challenges that must be addressed. Overall, this review has important guiding significance for the future design of new paradigms of stem cell products to improve their therapeutic efficacy.

Glutathione depletion and dihydroorotate dehydrogenase inhibition actuated ferroptosis-augment to surmount triple-negative breast cancer.

Ferroptosis is a promising therapeutic approach for combating malignant cancers, but its effectiveness is limited in clinical due to the adaptability and self-repair abilities of cancer cells. Mitochondria, as the pivotal player in ferroptosis, exhibit tremendous therapeutic potential by targeting the intramitochondrial anti-ferroptotic pathway mediated by dihydroorotate dehydrogenase (DHODH). In this study, an albumin-based nanomedicine was developed to induce augmented ferroptosis in triple-negative breast cancer (TNBC) by depleting glutathione (GSH) and inhibiting DHODH activity. The nanomedicine (ATO/SRF@BSA) was developed by loading sorafenib (SRF) and atovaquone (ATO) into bovine serum albumin (BSA). SRF is an FDA-approved ferroptosis inducer and ATO is the only drug used in clinical that targets mitochondria. By combining the effects of SRF and ATO, ATO/SRF@BSA promoted the accumulation of lipid peroxides within mitochondria by inhibiting the glutathione peroxidase 4 (GPX4)-GSH pathway and downregulating the DHODH-coenzyme Q (CoQH2) defense mechanism, triggers a burst of lipid peroxides. Simultaneously, ATO/SRF@BSA suppressed cancer cell self-repair and enhanced cell death by inhibiting the synthesis of adenosine triphosphate (ATP) and pyrimidine nucleotides. Furthermore, the anti-cancer results showed that ATO/SRF@BSA exhibited tumor-specific killing efficacy, significantly improved the tumor hypoxic microenvironment, and lessened the toxic side effects of SRF. This work presents an efficient and easily achievable strategy for TNBC treatment, which may hold promise for clinical applications.

A Pro-Metastatic Derivatives Eliminator for In Vivo Dual-Removal of Circulating Tumor Cells and Tumor-Derived Exosomes Impedes their Biodistribution into Distant Organs.

Circulating tumor cells (CTCs) and tumor-derived exosomes (TDEs) play an irreplaceable role in the metastatic cascade and preventing them from reaching distant organs via blood circulation helps to reduce the probability of cancer recurrence and metastasis. However, technologies that can simultaneously prevent CTCs and TDEs from reaching distant organs have not been thoroughly developed until now. Here, inspired by hemoperfusion, a pro-metastatic derivative eliminator (PMDE) is developed for the removal of both CTCs and TDEs from the peripheral blood, which also inhibits their biodistribution in distant organs. This device is designed with a dual antibody-modified immunosorbent filled into a capture column that draws peripheral blood out of the body to flow through the column to specifically capture CTCs and TDEs, followed by retransfusing the purified blood into the body. The PMDE can efficiently remove CTCs and TDEs from the peripheral blood and has excellent biocompatibility. Interestingly, the PMDE device can significantly inhibit the biodistribution of CTCs and TDEs in the lung and liver by scavenging them. This work provides a new perspective on anti-metastatic therapy and has broad prospects in clinical applications to prevent metastasis and recurrence.

Progress on the pathological tissue microenvironment barrier-modulated nanomedicine.

Imbalance in the tissue microenvironment is the main obstacle to drug delivery and distribution in the human body. Before penetrating the pathological tissue microenvironment to the target site, therapeutic agents are usually accompanied by three consumption steps: the first step is tissue physical barriers for prevention of their penetration, the second step is inactivation of them by biological molecules, and the third step is a cytoprotective mechanism for preventing them from functioning on specific subcellular organelles. However, recent studies in drug-hindering mainly focus on normal physiological rather than pathological microenvironment, and the repair of damaged physiological barriers is also rarely discussed. Actually, both the modulation of pathological barriers and the repair of damaged physiological barriers are essential in the disease treatment and the homeostasis maintenance. In this review, we present an overview describing the latest advances in the generality of these pathological barriers and barrier-modulated nanomedicine. Overall, this review holds considerable significance for guiding the design of nanomedicine to increase drug efficacy in the future.

Tumor microenvironment-initiated lipid redox cycling for efficient triple-negative breast cancer therapy.

The use of overwhelming reactive oxygen species (ROS) attack has shown great potential for treating aggressive malignancies; however, targeting this process for further applications is greatly hindered by inefficiency and low selectivity. Here, a novel strategy for ROS explosion induced by tumor microenvironment-initiated lipid redox cycling was proposed, which was developed by using soybean phosphatidylcholine (SPC) to encapsulate lactate oxidase (LOX) and sorafenib (SRF) self-assembled nanoparticles (NPs), named LOX/SRF@Lip. SPC is not only the delivery carrier but an unsaturated lipid supplement for ROS explosion. And LOX catalyzes excessive intratumoral lactate to promote the accumulation of large amounts of H2O2. Then, H2O2 reacts with excessive endogenous iron ions to generate amounts of hydroxyl radical for the initiation of SPC peroxidation. Once started, the reaction will proceed via propagation to form new lipid peroxides (LPO), resulting to devastating LPO explosion and widespread oxidative damage in tumor cells. Furthermore, SRF makes contribution to mass LPO accumulation by inhibiting LPO elimination. Compared to normal tissue, tumor tissue has higher levels of lactate and iron ions. Therefore, LOX/SRF@Lip shows low toxicity in normal tissues, but generates efficient inhibition on tumor proliferation and metastasis, enabling excellent and safe tumor-specific therapy. This work offers new ideas on how to magnify anticancer effect of ROS through rational nanosystem design and tumor-specific microenvironment utilization.

A novel whole blood purifier for efficient capture and separation of circulating tumor cells.

Circulating tumor cells (CTCs) as important biomarkers for noninvasive clinical diagnosis and prognostic evaluation are significant in predicting the overall survival and progression-free survival of cancer patients. However, the current typical CTCs separation and enrichment techniques were limited to a single collection of small-volume blood samples, which was inadequate to comprehensively profile the distribution of CTCs in the systemic blood. In addition, those techniques cannot reduce metastasis of CTCs unless adjuvant chemotherapy. Herein, inspired by hemodialysis, we designed a whole blood purifier (WBP) composed of a functionalized special spiral-like glass tube modified by anti-epithelial cell adhesion molecule (anti-EpCAM). The WBP allowed real-time capture, enrichment and removal of CTCs from systemic blood circulation, and the purified blood was immediately returned to the body. Furthermore, the WBP did not cause any organic damages in vivo. This approach achieves the high accuracy of liquid biopsy technology and is expected to become an effective clinical adjuvant therapy for tumor metastasis.

Hypoxia Inhibitor Combined with Chemotherapeutic Agents for Antitumor and Antimetastatic Efficacy against Osteosarcoma.

Chemotherapy is the main treatment method for osteosarcoma in the clinic. However, drug resistance and its poor antimetastatic effects greatly limit its clinical application. In this work, dual-drug nanoparticles (NPs) containing albendazole (ABZ) and doxorubicin (DOX), named AD@PLGA-PEG NPs, were prepared to solve the problems of chemotherapeutic drug resistance and poor antimetastasis effects. Compared with free DOX, ABZ combined with DOX can increase intracellular reactive oxygen species (ROS) and induce more tumor cell apoptosis; therefore, AD@PLGA-PEG NPs produced more mitochondria-mediated oxidative stress and better apoptosis efficiency. Importantly, ABZ can also effectively inhibit the expression of hypoxia inducible factor-1α (HIF-1α) and then reduce the expression of its downstream vascular endothelial growth factor (VEGF); thus, the AD@PLGA-PEG NPs effectively inhibited tumor metastasis in vivo. Collectively, the dual-drug AD@PLGA-PEG NPs delivery system provided prominent antitumor and antimetastatic efficacy and might be a promising treatment for osteosarcoma.

Injectable rhein-assisted crosslinked hydrogel for efficient local osteosarcoma chemotherapy.

Osteosarcoma (OS) is the most common malignant tumor of the bone that affects children and adolescents, and its treatment usually involves doxorubicin hydrochloride (DOX). However, the drug resistance and side effects caused by high-dose DOX infusion greatly hinder its therapeutic effects. To achieve efficient OS treatment with low toxicity, an injectable rhein (RH)-assisted crosslinked hydrogel (PVA@RH@DOX hydrogel, PRDH) was designed, which was prepared by loading DOX and RH into a polyvinyl alcohol (PVA) solution. The cytotoxicity assay and live/dead staining results showed that the combination of RH and DOX more effectively killed OS cells, producing excellent effects at low concentrations of DOX. The wound healing and transwell test results proved that PRDH could significantly inhibit the metastasis and invasion of OS cells. PRDH showed a long-lasting antitumor effect after injection of a single dose, significantly suppressing the proliferation and metastasis of OS and achieving the strategy of a single administration for long-term treatment. Excitingly, RH facilitated hydrogel formation by assisting with PVA crosslinking. This system provides an alternative regimen and broadens the horizon for the clinical treatment of OS.

Pathological collagen targeting and penetrating liposomes for idiopathic pulmonary fibrosis therapy.

Idiopathic pulmonary fibrosis (IPF) is a fibrotic interstitial lung disease in which collagen progressively deposits in the supporting framework of the lungs. The pathological collagen creates a recalcitrant barrier in mesenchyme for drug penetration, thus greatly restricting the therapeutical efficacy. On the other hand, this overloaded collagen is gradually exposed to the bloodstream at fibrotic sites because of the vascular hyperpermeability, thus serving as a potential target. Herein, pathological collagen targeting and penetrating liposomes (DP-CC) were constructed to deliver anti-fibrotic dual drugs including pirfenidone (PFD) and dexamethasone (DEX) deep into injured alveoli. The liposomes were co-decorated with collagen binding peptide (CBP) and collagenase (COL). CBP could help vehicle recognize the pathological collagen and target the fibrotic lungs efficiently because of its high affinity to collagen, and COL assisted in breaking through the collagen barrier and delivering vehicle to the center of injured sites. Then, the released dual drugs developed a synergistic anti-fibrotic effect to repair the damaged epithelium and remodel the extracellular matrix (ECM), thus rebuilding the lung architecture. This study provides a promising strategy to deliver drugs deep into pathological collagen accumulated sites for the enhanced treatment of IPF.

Photothermal nanozyme-ignited Fenton reaction-independent ferroptosis for breast cancer therapy.

Ferroptosis is a type of programmed cell death caused by the iron-dependent lipid hydroperoxide pathway and has attracted significant interest. However, Fenton reaction-dependent ferroptosis has shown unsatisfactory therapeutic effects in tumor therapy, mainly due to inadequate reaction conditions in the tumor microenvironment. Here, we report a new strategy for Fenton-independent pathway by employing photothermal nanozyme to overcome limitations of the low efficiency of Fenton reaction. Specifically, we used iron redox pair (Fe2+/Fe3+)-containing hollow mesoporous Prussian blue (HMPB) nanocubes as the iron sources to fabricate iron-loaded liposome (HMPB@Lip). HMPB@Lip not only exerts the photothermal therapy, but also functions as nanozyme catalyzing lipid peroxidation for ferroptosis therapy. Importantly, Fenton reaction-independent ferroptosis triggered by photothermal nanozyme achieved effective tumor ablation. Therefore, HMPB@Lip can be used as a potential multifunctional nanozyme for effective Fenton reaction-independent ferroptosis therapy.

A Harmless-Harmful Switchable and Uninterrupted Laccase-Instructed Killer for Activatable Chemodynamic Therapy.

Chemodynamic therapy (CDT) employs Fenton catalysts to kill cancer cells by converting intracellular hydrogen peroxide (H2 O2 ) into hydroxyl radicals (OH•). Although many studies on H2 O2 supplementation have been conducted to improve the therapeutic effect of CDT, few studies have focused on the application of superoxide radical (O2 -• ) in CDT, which may result in better efficacy. A major concern about O2 -• -mediated CDT is its tendency to induce serious oxidative damage to normal tissues, which may be addressed by using a degradable O2 -• scavenger. Here, a harmless-harmful switchable and uninterrupted laccase (LAC)-instructed killer (HULK) is constructed, which is the first CDT agent accelerated by LAC-instructed O2 -• generation and possesses a harmless-harmful switchable effect because of the photodegradation of the O2 -• scavenger iron-chlorin e6 (FeCe6). LAC-instructed substrate oxidation effectively catalyzes O2 -• production with the help of intracellular reduction, thereby promoting the conversion of Fe3+ to Fe2+ , accelerating the generation of OH•, and inducing tumor cell apoptosis and necrosis. The introduced O2 -• scavenger FeCe6 is quickly photodegraded during irradiation, while LAC-instructed O2 -• generation proceeds as before, resulting in activatable CDT. This work not only provides the first strategy for LAC-instructed O2 -• generation but also presents new insight into activatable CDT.

A carrier-free anti-inflammatory platinum (II) self-delivered nanoprodrug for enhanced breast cancer therapy.

Cisplatin is one of the most used first-line anticancer drugs for various solid tumor therapies. However, cisplatin-based chemotherapy can induce tumor cells to secrete excessive prostaglandin E2 (PGE2) catalyzed by cyclooxygenase-2 (COX-2), which, in turn, counteracts its chemotherapeutic effect and further accelerates tumor metastasis. Here, we report a carrier-free self-delivered nanoprodrug based on platinum (II) coordination bonding coupled with tolfenamic acid (Tolf) (named Tolfplatin). Tolfplatin can spontaneously assemble into uniformly sized nanoparticles (NPs) with a high drug-loading capacity. Compared with cisplatin, Tolfplatin NPs can facilitate cellular uptake, significantly decrease PGE2 secretion by COX-2 inhibition, which further downregulate tumorous anti-apoptotic and metastasis-associated proteins, thereby efficiently inducing apoptotic cell death and significantly inhibit tumor metastasis in vitro and in vivo. Therefore, as the carrier-free nanoprodrug, Tolfplatin NPs are promising anti-tumoral agents to inhibit tumor proliferation and metastasis by enriching the function and promoting the anti-tumor activity of cisplatin.

Monocyte-derived multipotent cell delivered programmed therapeutics to reverse idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a highly heterogeneous and fatal disease. However, IPF treatment has been limited by the low drug delivery efficiency to lungs and dysfunctional "injured" type II alveolar epithelial cell (AEC II). Here, we present surface-engineered nanoparticles (PER NPs) loading astaxanthin (AST) and trametinib (TRA) adhered to monocyte-derived multipotent cell (MOMC) forming programmed therapeutics (MOMC/PER). Specifically, the cell surface is designed to backpack plenty of PER NPs that reach directly to the lungs due to the homing characteristic of the MOMC and released PER NPs retarget injured AEC II after responding to the matrix metalloproteinase-2 (MMP-2) in IPF tissues. Then, released AST can enhance synergetic effect of TRA for inhibiting myofibroblast activation, and MOMC can also repair injured AEC II to promote damaged lung regeneration. Our findings provide proof of concept for developing a strategy for cell-mediated lung-targeted delivery platform carrying dual combined therapies to reverse IPF.

Nanoengineered immunosuppressive therapeutics modulating M1/M2 macrophages into the balanced status for enhanced idiopathic pulmonary fibrosis therapy.

Effective treatment in clinic for idiopathic pulmonary fibrosis (IPF) remains a challenge due to low drug accumulation in lungs and imbalanced polarization of pro/anti-inflammatory macrophages (M1/M2 macrophages). Herein, a novel endogenous cell-targeting nanoplatform (PNCE) is developed for enhanced IPF treatment efficacy through modulating M1/M2 macrophages into the balanced status to suppress fibroblast over-activation. Notably, PNCE loaded with nintedanib (NIN) and colchicine (COL) can firstly target endogenous monocyte-derived multipotent cells (MOMCs) and then be effectively delivered into IPF lungs due to the homing ability of MOMCs, and detached sensitively from MOMCs by matrix metalloproteinases-2 (MMP-2) over-expressed in IPF lungs. After PNCE selectively accumulated within fibrosis foci, COL can mildly modulate the polarization of M1 macrophages into M2 macrophages to balance innate immune responses, which can enhance the suppressing effect of NIN on fibroblast activation, further improving the IPF therapy. Altogether, PNCE has two collaborative steps including the inhibition of innate immune responses accompanied by the decrease of fibroblast populations in IPF lungs, achieving a stronger and excellent anti-fibrotic efficacy both in vitro and in vivo. This endogenous cell-based engineered liposomal nanoplatform not only allows therapeutic drugs to take effect selectively in vivo, but also provides an alternative strategy for an enhanced curative effect by modulating innate immune responses in IPF therapy.

Synergistic Platinum(II) Prodrug Nanoparticles for Enhanced Breast Cancer Therapy.

Chemotherapy still accounts for a large proportion of the treatments of tumors, but the drug resistance and side effects caused by long-term chemotherapy should not be underestimated. In this work, the drug combination strategy has been widely developed to overcome the side effects brought by the use of single drugs and improve the therapeutic effect. However, in clinical applications, the co-delivery of drugs is very difficult, and different in vivo kinetics due to different drug properties will lead to a decrease in efficacy. Thus, the design of novel antitumor therapeutic agents, including new platinum agents, represents an area in need of urgent attention. Our investigation implies a promising strategy for the design of a platinum prodrug to enhance the treatment of breast cancer. A dual-drug delivery nanoparticle was developed for enhanced treatment of breast cancer based on a two-into-one co-delivery strategy. Through the synergistic effect of released cisplatin hydrate and tolfenamic acid (COX-2 inhibitor) from the coordination prodrug, the tumor growth is significantly suppressed, and the survival time is greatly extended in breast tumor-bearing mice.

Amplification of tumor antigen presentation by NLGplatin to improve chemoimmunotherapy.

Oxaliplatin is a chemotherapeutic agent widely used in cancer treatment whereas its immunosuppressive effect hinders the progress of immunotherapy. Here we have synthesized a new compound NLGplatin constructed by combining oxaliplatin (OXA) and indoleamine 2,3-dioxygenase (IDO) inhibitor NLG919. The NLGplatin acquires chemotherapeutic properties of OXA and can activate the immune system, and also retains the ability to inhibit IDO enzyme activity without affecting the proliferation of immune cells. This difunctional drug has a great potential to achieve effective cancer chemoimmunotherapy.

Inhibition of breast cancer proliferation and metastasis by strengthening host immunity with a prolonged oxygen-generating phototherapy hydrogel.

Hypoxia is a potent tumor microenvironmental (TME) factor promoting immunosuppression and metastatic progression. For current anticancer therapeutic strategies, the combination of hypoxia alleviation and photodynamic therapy (PDT) might be a useful approach to further improve anticancer efficacy. In this study, we alleviated tumor hypoxia using a prolonged oxygen-generating phototherapy hydrogel (POP-Gel), which effectively elevated the oxygen level and shrank the hypoxic regions of tumors for up to 5 days evaluated by photoacoustic (PA) imaging and immunofluorescence staining, meeting the requirement of the "once injection, sustained treatment" strategy and significantly increasing PDT efficacy. The long-period improvement of the tumor hostile environment downregulated the expression of hypoxia inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF), further preventing tumor growth and metastasis. More importantly, the enhanced PDT triggered a more intense immune response, improving the inhibition of triple negative breast cancer growth even tumor elimination. The POP-Gel may contribute useful insights into the combination of hypoxia alleviation and PDT.

Light triggered oxygen-affording engines for repeated hypoxia-resistant photodynamic therapy.

Hypoxia is the trickiest barrier for oncotherapy, which can cause the resistance of various tumor treatments, even promote cancer progression and metastasis, especially in the treatment of photodynamic therapy (PDT). Therefore, alleviating tumor hypoxia would be a favorable modality to improve PDT treatment. In this study, we designed an innovative biological oxygen-evolving material, autotrophic light-triggered green affording­oxygen engine (ALGAE), which could perform an on-off switchable and inexhaustible oxygen generation triggered by the same irradiation of PDT with good biocompatibility and degradability. And the hypoxia-resistant PDT induced by ALGAE could successfully eradicate tumors and avoid tumor metastasis. The ALGAE system could be standby in a long period for efficient oxygen-affording around tumors, which not only dramatically alleviated tumor hypoxia but also achieved a high-efficiency and repetitive PDT treatments. Furthermore, the innovative biological oxygen-affording engine described in the study presents a new class of oxygen-generating material for hypoxia-resistant cancer therapy.

An energy-blocking nanoparticle decorated with anti-VEGF antibody to reverse chemotherapeutic drug resistance.

Multi-drug resistance (MDR) of tumor cells has greatly hindered the therapeutic efficacy of chemotherapeutic drugs, resulting in chemotherapy failure, while overexpression of ATP-binding cassette (ABC) transporters in cell membranes is the leading cause of MDR. In this study, we reported novel self-assembled triphenylphosphine-quercetin-polyethylene glycol-monoclonal antibody nanoparticles (TQ-PEG-mAb NPs) for overcoming MDR primarily through mitochondrial damage to block ATP supply to ABC transporters both in vitro and in vivo. The doxorubicin (DOX)-loaded NPs (TQ/DOX-PEG-mAb) were composed of two drugs (TQ and DOX) and an outer shielding shell of the PEG-mAb conjugate. Besides, the outer shell could be acid-responsively detached to expose the positive charge of TQ inside the NPs to enhance cellular uptake. TQ was proved to effectively induce mitochondrial damage with increased ROS levels and depolarization of mitochondrial membrane potential (MMP), leading to prominently reduced ATP supply to ABC transporters. Moreover, the involvement of the anti-vascular endothelial growth factor (VEGF) mAb was not only for efficient targeting but also for combined therapy. Consequently, TQ/DOX-PEG-mAb showed that the internalized amount of DOX was largely improved while the efflux amount was dramatically inhibited on MCF-7/ADR cells, indicating excellent reversal of DOX resistance. Importantly, the growth of DOX-resistant breast tumors was significantly inhibited with no evident systemic toxicity. Therefore, the employment of TQ-PEG-mAb is believed to be a new approach to improve the efficacy of chemotherapeutic drugs in MDR tumors.