Combinatorial design of siloxane-incorporated lipid nanoparticles augments intracellular processing for tissue-specific mRNA therapeutic delivery.

Systemic delivery of messenger RNA (mRNA) for tissue-specific targeting using lipid nanoparticles (LNPs) holds great therapeutic potential. Nevertheless, how the structural characteristics of ionizable lipids (lipidoids) impact their capability to target cells and organs remains unclear. Here we engineered a class of siloxane-based ionizable lipids with varying structures and formulated siloxane-incorporated LNPs (SiLNPs) to control in vivo mRNA delivery to the liver, lung and spleen in mice. The siloxane moieties enhance cellular internalization of mRNA-LNPs and improve their endosomal escape capacity, augmenting their mRNA delivery efficacy. Using organ-specific SiLNPs to deliver gene editing machinery, we achieve robust gene knockout in the liver of wild-type mice and in the lungs of both transgenic GFP and Lewis lung carcinoma (LLC) tumour-bearing mice. Moreover, we showed effective recovery from viral infection-induced lung damage by delivering angiogenic factors with lung-targeted Si5-N14 LNPs. We envision that our SiLNPs will aid in the clinical translation of mRNA therapeutics for next-generation tissue-specific protein replacement therapies, regenerative medicine and gene editing.

Tumour-derived small extracellular vesicles act as a barrier to therapeutic nanoparticle delivery.

Nanoparticles are promising for drug delivery applications, with several clinically approved products. However, attaining high nanoparticle accumulation in solid tumours remains challenging. Here we show that tumour cell-derived small extracellular vesicles (sEVs) block nanoparticle delivery to tumours, unveiling another barrier to nanoparticle-based tumour therapy. Tumour cells secrete large amounts of sEVs in the tumour microenvironment, which then bind to nanoparticles entering tumour tissue and traffic them to liver Kupffer cells for degradation. Knockdown of Rab27a, a gene that controls sEV secretion, decreases sEV levels and improves nanoparticle accumulation in tumour tissue. The therapeutic efficacy of messenger RNAs encoding tumour suppressing and proinflammatory proteins is greatly improved when co-encapsulated with Rab27a small interfering RNA in lipid nanoparticles. Together, our results demonstrate that tumour cell-derived sEVs act as a defence system against nanoparticle tumour delivery and that this system may be a potential target for improving nanoparticle-based tumour therapies.

Dual-Locked Fluorescent Probes Activated by Aminopeptidase N and the Tumor Redox Environment for High-Precision Imaging of Tumor Boundaries.

Clear delineation of tumor margins is essential for accurate resection and decreased recurrence rate in the clinic. Fluorescence imaging is emerging as a promising alternative to traditional visual inspection by surgeons for intraoperative imaging. However, traditional probes lack accuracy in tumor diagnosis, making it difficult to depict tumor boundaries accurately. Herein, we proposed an offensive and defensive integration (ODI) strategy based on the "attack systems (invasive peptidase) and defense systems (reductive microenvironment)" of multi-dimensional tumor characteristics to design activatable fluorescent probes for imaging tumor boundaries precisely. Screened out from a series of ODI strategy-based probes, ANQ performed better than traditional probes based on tumor unilateral correlation by distinguishing between tumor cells and normal cells and minimizing false-positive signals from living metabolic organs. To further improve the signal-to-background ratio in vivo, derivatized FANQ, was prepared and successfully applied to distinguish orthotopic hepatocellular carcinoma tissues from adjacent tissues in mice models and clinical samples. This work highlights an innovative strategy to develop activatable probes for rapid diagnosis of tumors and high-precision imaging of tumor boundaries, providing more efficient tools for future clinical applications in intraoperative assisted resection.

Anti-lymphangiogenesis for boosting drug accumulation in tumors.

The inadequate tumor accumulation of anti-cancer agents is a major shortcoming of current therapeutic drugs and remains an even more significant concern in the clinical prospects for nanomedicines. Various strategies aiming at regulating the intratumoral permeability of therapeutic drugs have been explored in preclinical studies, with a primary focus on vascular regulation and stromal reduction. However, these methods may trigger or facilitate tumor metastasis as a tradeoff. Therefore, there is an urgent need for innovative strategies that boost intratumoral drug accumulation without compromising treatment outcomes. As another important factor affecting drug tumor accumulation besides vasculature and stroma, the impact of tumor-associated lymphatic vessels (LVs) has not been widely considered. In the current research, we verified that anlotinib, a tyrosine kinase inhibitor with anti-lymphangiogenesis activity, and SAR131675, a selective VEGFR-3 inhibitor, effectively decreased the density of tumor lymphatic vessels in mouse cancer models, further enhancing drug accumulation in tumor tissue. By combining anlotinib with therapeutic drugs, including doxorubicin (Dox), liposomal doxorubicin (Lip-Dox), and anti-PD-L1 antibody, we observed improved anti-tumor efficacy in comparison with monotherapy regimens. Meanwhile, this strategy significantly reduced tumor metastasis and elicited stronger anti-tumor immune responses. Our work describes a new, clinically transferrable approach to augmenting intratumoral drug accumulation, which shows great potential to address the current, unsatisfactory efficacies of therapeutic drugs without introducing metastatic risk.

Precision treatment of viral pneumonia through macrophage-targeted lipid nanoparticle delivery.

Macrophages are integral components of the innate immune system, playing a dual role in host defense during infection and pathophysiological states. Macrophages contribute to immune responses and aid in combatting various infections, yet their production of abundant proinflammatory cytokines can lead to uncontrolled inflammation and worsened tissue damage. Therefore, reducing macrophage-derived proinflammatory cytokine release represents a promising approach for treating various acute and chronic inflammatory disorders. However, limited macrophage-specific delivery vehicles have hindered the development of macrophage-targeted therapies. In this study, we screened a pool of 112 lipid nanoparticles (LNPs) to identify an optimal LNP formulation for efficient siRNA delivery. Subsequently, by conjugating the macrophage-specific antibody F4/80 to the LNP surface, we constructed MacLNP, an enhanced LNP formulation designed for targeted macrophage delivery. In both in vitro and in vivo experiments, MacLNP demonstrated a significant enhancement in targeting macrophages. Specifically, delivery of siRNA targeting TAK1, a critical kinase upstream of multiple inflammatory pathways, effectively suppressed the phosphorylation/activation of NF-kB. LNP-mediated inhibition of NF-kB, a key upstream regulator in the classic inflammatory signaling pathway, in the murine macrophage cell line RAW264.7 significantly reduced the release of proinflammatory cytokines after stimulation with the viral RNA mimic Poly(I:C). Finally, intranasal administration of MacLNP-encapsulated TAK1 siRNA markedly ameliorated lung injury induced by influenza infection. In conclusion, our findings validate the potential of targeted macrophage interventions in attenuating inflammatory responses, reinforcing the potential of LNP-mediated macrophage targeting to treat pulmonary inflammatory disorders.

High-throughput barcoding of nanoparticles identifies cationic, degradable lipid-like materials for mRNA delivery to the lungs in female preclinical models.

Lipid nanoparticles for delivering mRNA therapeutics hold immense promise for the treatment of a wide range of lung-associated diseases. However, the lack of effective methodologies capable of identifying the pulmonary delivery profile of chemically distinct lipid libraries poses a significant obstacle to the advancement of mRNA therapeutics. Here we report the implementation of a barcoded high-throughput screening system as a means to identify the lung-targeting efficacy of cationic, degradable lipid-like materials. We combinatorially synthesize 180 cationic, degradable lipids which are initially screened in vitro. We then use barcoding technology to quantify how the selected 96 distinct lipid nanoparticles deliver DNA barcodes in vivo. The top-performing nanoparticle formulation delivering Cas9-based genetic editors exhibits therapeutic potential for antiangiogenic cancer therapy within a lung tumor model in female mice. These data demonstrate that employing high-throughput barcoding technology as a screening tool for identifying nanoparticles with lung tropism holds potential for the development of next-generation extrahepatic delivery platforms.

Emerging nanotechnological approaches to regulating tumor vasculature for cancer therapy.

Abnormal angiogenesis stands for one of the most striking manifestations of malignant tumor. The pathologically and structurally abnormal tumor vasculature facilitates a hostile tumor microenvironment, providing an ideal refuge exclusively for cancer cells. The emergence of vascular regulation drugs has introduced a distinctive class of therapeutics capable of influencing nutrition supply and drug delivery efficacy without the need to penetrate a series of physical barriers to reach tumor cells. Nanomedicines have been further developed for more precise regulation of tumor vasculature with the capacity of co-delivering multiple active pharmaceutical ingredients, which overall reduces the systemic toxicity and boosts the therapeutic efficacy of free drugs. Additionally, precise structure design enables the integration of specific functional motifs, such as surface-targeting ligands, droppable shells, degradable framework, or stimuli-responsive components into nanomedicines, which can improve tissue-specific accumulation, enhance tissue penetration, and realize the controlled and stimulus-triggered release of the loaded cargo. This review describes the morphological and functional characteristics of tumor blood vessels and summarizes the pivotal molecular targets commonly used in nanomedicine design, and then highlights the recent cutting-edge advancements utilizing nanotechnologies for precise regulation of tumor vasculature. Finally, the challenges and future directions of this field are discussed.

Synergistic phototherapy of NIR wavelength xanthene-quinoline salt-based heavy-atom-free photosensitizers for tumor therapy.

We propose a practical strategy to design a series of heavy-atom-free synergistic phototherapy agents (CSQs) with both photodynamic therapy (PDT) and photothermal therapy (PTT) under NIR wavelength excitation by simply replacing the indole salt of xanthene Changsha (CS) with quinoline salt.

LncRNA H19 Regulates Breast Cancer DNA Damage Response and Sensitivity to PARP Inhibitors via Binding to ILF2.

Although DNA damage repair plays a critical role in cancer chemotherapy, the function of lncRNAs in this process remains largely unclear. In this study, in silico screening identified H19 as an lncRNA that potentially plays a role in DNA damage response and sensitivity to PARP inhibitors. Increased expression of H19 is correlated with disease progression and with a poor prognosis in breast cancer. In breast cancer cells, forced expression of H19 promotes DNA damage repair and resistance to PARP inhibition, whereas H19 depletion diminishes DNA damage repair and increases sensitivity to PARP inhibitors. H19 exerted its functional roles via direct interaction with ILF2 in the cell nucleus. H19 and ILF2 increased BRCA1 stability via the ubiquitin-proteasome proteolytic pathway via the H19- and ILF2-regulated BRCA1 ubiquitin ligases HUWE1 and UBE2T. In summary, this study has identified a novel mechanism to promote BRCA1-deficiency in breast cancer cells. Therefore, targeting the H19/ILF2/BRCA1 axis might modulate therapeutic approaches in breast cancer.

RIG-I Promotes Tumorigenesis and Confers Radioresistance of Esophageal Squamous Cell Carcinoma by Regulating DUSP6.

We investigated the expression and biological function of retinoic acid inducible gene I (RIG-I) in esophageal squamous cell carcinoma (ESCC). Materials and methods: An immunohistochemical analysis was performed on 86 pairs of tumor tissue and adjacent normal tissue samples of patients with ESCC. We generated RIG-I-overexpressing ESCC cell lines KYSE70 and KYSE450, and RIG-I- knockdown cell lines KYSE150 and KYSE510. Cell viability, migration and invasion, radioresistance, DNA damage, and cell cycle were evaluated using CCK-8, wound-healing and transwell assay, colony formation, immunofluorescence, and flow cytometry and Western blotting, respectively. RNA sequencing was performed to determine the differential gene expression between controls and RIG-I knockdown. Tumor growth and radioresistance were assessed in nude mice using xenograft models. RIG-I expression was higher in ESCC tissues compared with that in matched non-tumor tissues. RIG-I overexpressing cells had a higher proliferation rate than RIG-I knockdown cells. Moreover, the knockdown of RIG-I slowed migration and invasion rates, whereas the overexpression of RIG-I accelerated migration and invasion rates. RIG-I overexpression induced radioresistance and G2/M phase arrest and reduced DNA damage after exposure to ionizing radiations compared with controls; however, it silenced the RIG-I enhanced radiosensitivity and DNA damage, and reduced the G2/M phase arrest. RNA sequencing revealed that the downstream genes DUSP6 and RIG-I had the same biological function; silencing DUSP6 can reduce the radioresistance caused by the overexpression of RIG-I. RIG-I knockdown depleted tumor growth in vivo, and radiation exposure effectively delayed the growth of xenograft tumors compared with the control group. RIG-I enhances the progression and radioresistance of ESCC; therefore, it may be a new potential target for ESCC-targeted therapy.

Platelet-Mimicking Nanosponges for Functional Reversal of Antiplatelet Agents.

BACKGROUND: During long-term antiplatelet agents (APAs) administration, patients with thrombotic diseases take a fairly high risk of life-threatening bleeding, especially when in need of urgent surgery. Rapid functional reversal of APAs remains an issue yet to be efficiently resolved by far due to the lack of any specific reversal agent in the clinic, which greatly restricts the use of APAs. METHODS: Flow cytometry analysis was first applied to assess the dose-dependent reversal activity of platelet-mimicking perfluorocarbon-based nanosponges (PLT-PFCs) toward ticagrelor. The tail bleeding time of mice treated with APAs followed by PLT-PFCs was recorded at different time points, along with corresponding pharmacokinetic analysis of ticagrelor and tirofiban. A hemorrhagic transformation model was established in experimental stroke mice with thrombolytic/antiplatelet therapy. Magnetic resonance imaging was subsequently applied to observe hemorrhage and thrombosis in vivo. Further evaluation of the spontaneous clot formation activity of PLT-PFCs was achieved by clot retraction assay in vitro. RESULTS: PLT-PFCs potently reversed the antiplatelet effect of APAs by competitively binding with APAs. PLT-PFCs showed high binding affinity comparable to fresh platelets in vitro with first-line APAs, ticagrelor and tirofiban, and efficiently reversed their function in both tail bleeding and postischemic-reperfusion models. Moreover, the deficiency of platelet intrinsic thrombotic activity diminished the risk of thrombogenesis. CONCLUSIONS: This study demonstrated the safety and effectiveness of platelet-mimicking nanosponges in ameliorating the bleeding risk of different APAs, which offers a promising strategy for the management of bleeding complications induced by antiplatelet therapy.

Penetrating Macrophage-Based Nanoformulation for Periodontitis Treatment.

Periodontitis is a chronic inflammatory disease caused by the interaction of oral microorganisms with the host immune response. Porphyromonas gingivalis (P.g.) acts as a key mediator in subverting the homeostasis of the local immune system. On the one hand, P.g. inhibits phagocytosis and the killing capacity of immune cells. On the other hand, P.g. increases selective cytokine release, which is beneficial to its further proliferation. Here, we prepared a penetrating macrophage-based nanoformulation (MZ@PNM)-encapsulating hydrogel (MZ@PNM@GCP) that responded to the periodontitis microenvironment. MZ@PNM targeted P.g. via the Toll-like receptor complex 2/1 (TLR2/1) on its macrophage-mimicking membrane, then directly killed P.g. through disruption of bacterial structural integrity by the cationic nanoparticles and intracellular release of an antibacterial drug, metronidazole (MZ). Meanwhile, MZ@PNM interrupted the specific binding of P.g. to immune cells and neutralized complement component 5a (C5a), preventing P.g. subversion of periodontal host immune response. Overall, MZ@PNM@GCP showed potent efficacy in periodontitis treatment, restoring local immune function and killing pathogenic bacteria, while exhibiting favorable biocompatibility, all of which have been demonstrated both in vivo and in vitro.

Ultrafast Laser-Ablated Bioinspired Hydrogel-Based Porous Gating System for Sustained Drug Release.

Gating systems have been extensively researched in energy harvesting, lab-on-chip applications, and so forth. However, the controlled drug delivery system with artificial hydrogel-based porous gating systems (HPGSs) is rarely reported. Herein, a biomimetic HPGS with a pH-responsive hydrogel as the valve and polydimethylsiloxane as the frame is fabricated by in situ femtosecond laser microdrilling and subsequent ultraviolet exposure. The proposed HPGS loaded with doxorubicin hydrochloride (DOX) is stable under physiological conditions, has a low drug leakage rate, and can achieve sustained drug release in a low pH environment. The experimental results show that the drug release is mainly controlled by non-Fickian diffusion, which renders the dynamic speed control of molecular transport possible. Moreover, the HPGS can also be prepared into an antitumor microcapsule. The results of in vitro cell experiments demonstrate that DOX@HPGS can release drugs and achieve terrific therapeutic efficacy in the elimination of HeLa cells in the acidic environments around tumor cells. This functional HPGS is envisioned to be an ideal pH-response carrier for sustained drug release treatment of digestive diseases such as inflammatory bowel disease and gastrointestinal cancer.

Platelet-Membrane-Coated Nanoparticles Enable Vascular Disrupting Agent Combining Anti-Angiogenic Drug for Improved Tumor Vessel Impairment.

Compared with traditional chemotherapeutics, vascular disruption agents (VDAs) have the advantages of rapidly blocking the supply of nutrients and starving tumors to death. Although the VDAs are effective under certain scenarios, this treatment triggers angiogenesis in the later stage of therapy that frequently leads to tumor recurrence and treatment failure. Additionally, the nonspecific tumor targeting and considerable side effects also impede the clinical applications of VDAs. Here we develop a customized strategy that combines a VDA with an anti-angiogenic drug (AAD) using mesoporous silica nanoparticles (MSNs) coated with platelet membrane for the self-assembled tumor targeting accumulation. The tailor-made nanoparticles accumulate in tumor tissues through the targeted adhesion of platelet membrane surface to damaged vessel sites, resulting in significant vascular disruption and efficient anti-angiogenesis in animal models. This study demonstrates the promising potential of combining VDA and AAD in a single nanoplatform for tumor eradication.

Bacterial Outer Membrane Vesicles Presenting Programmed Death 1 for Improved Cancer Immunotherapy via Immune Activation and Checkpoint Inhibition.

Natural, extracellular membrane vesicles secreted by Gram-negative bacteria, outer membrane vesicles (OMVs), contain numerous pathogen-associated molecular patterns which can activate systemic immune responses. Previous studies have shown that OMVs induce strong IFN-γ- and T cell-mediated anti-tumor effects in mice. However, IFN-γ is known to upregulate immunosuppressive factors in the tumor microenvironment, especially the immune checkpoint programmed death 1 ligand 1 (PD-L1), which may hamper T cell function and limit immunotherapeutic effectiveness. Here, we report the development of genetically engineered OMVs whose surface has been modified by insertion of the ectodomain of programmed death 1 (PD1). This genetic modification does not affect the ability of OMVs to trigger immune activation. More importantly, the engineered OMV-PD1 can bind to PD-L1 on the tumor cell surface and facilitate its internalization and reduction, thereby protecting T cells from the PD1/PD-L1 immune inhibitory axis. Through the combined effects of immune activation and checkpoint suppression, the engineered OMVs drive the accumulation of effector T cells in the tumor, which, in turn, leads to a greater impairment of tumor growth, compared with not only native OMVs but also the commonly used PD-L1 antibody. In conclusion, this work demonstrates the potential of bioengineered OMVs as effective immunotherapeutic agents that can comprehensively regulate the tumor immune microenvironment to effect markedly increased anti-tumor efficacy.

Combination of tumour-infarction therapy and chemotherapy via the co-delivery of doxorubicin and thrombin encapsulated in tumour-targeted nanoparticles.

Drugs that induce thrombosis in the tumour vasculature have not resulted in long-term tumour eradication owing to tumour regrowth from tissue in the surviving rim of the tumour, where tumour cells can derive nutrients from adjacent non-tumoral blood vessels and tissues. Here, we report the performance of a combination of tumour-infarction therapy and chemotherapy, delivered via chitosan-based nanoparticles decorated with a tumour-homing peptide targeting fibrin-fibronectin complexes overexpressed on tumour-vessel walls and in tumour stroma, and encapsulating the coagulation-inducing protease thrombin and the chemotherapeutic doxorubicin. Systemic administration of the nanoparticles into mice and rabbits bearing subcutaneous or orthotopic tumours resulted in higher tumour growth suppression and decreased tumour recurrence than nanoparticles delivering only thrombin or doxorubicin, with histological and haematological analyses indicating an absence of detectable toxicity. The co-administration of a cytotoxic payload and a protease to elicit vascular infarction in tumours with biodegradable tumour-targeted nanoparticles represents a promising strategy for improving the therapeutic index of coagulation-based tumour therapy.

A Bioinspired Nanoprobe with Multilevel Responsive T1 -Weighted MR Signal-Amplification Illuminates Ultrasmall Metastases.

Metastasis remains the major cause of death in cancer patients. Thus, there is a need to sensitively detect tumor metastasis, especially ultrasmall metastasis, for early diagnosis and precise treatment of cancer. Herein, an ultrasensitive T1 -weighted magnetic resonance imaging (MRI) contrast agent, UMFNP-CREKA is reported. By conjugating the ultrasmall manganese ferrite nanoparticles (UMFNPs) with a tumor-targeting penta-peptide CREKA (Cys-Arg-Glu-Lys-Ala), ultrasmall breast cancer metastases are accurately detected. With a behavior similar to neutrophils' immunosurveillance process for eliminating foreign pathogens, UMFNP-CREKA exhibits a chemotactic "targeting-activation" capacity. UMFNP-CREKA is recruited to the margin of tumor metastases by the binding of CREKA with fibrin-fibronectin complexes, which are abundant around tumors, and then release of manganese ions (Mn2+ ) to the metastasis in response to pathological parameters (mild acidity and elevated H2 O2 ). The localized release of Mn2+ and its interaction with proteins affects a marked amplification of T1 -weighted magnetic resonance (MR) signals. In vivo T1 -weighted MRI experiments reveal that UMFNP-CREKA can detect metastases at an unprecedented minimum detection limit of 0.39 mm, which has significantly extended the detection limit of previously reported MRI probe.

Targeting Delivery of Platelets Inhibitor to Prevent Tumor Metastasis.

Activated platelets have a high affinity for tumor cells, and consequently, they can protect tumor cells from environmental stress and immune attacks. Therefore, preventing platelet-tumor cell interaction can lead to the elimination of circulating tumor cells via natural killer cells and finally metastasis inhibition. It is also shown that CREKA (Cys-Arg-Glu-Lys-Ala), a tumor-homing pentapeptide, targets fibrin-fibronectin complexes that are found on the tumor stroma and the vessel walls. In this study, we linked CREKA to Ticagrelor, a reversible antagonist of the P2Y12 receptor on platelets. In vitro experiments indicated that CREKA-Ticagrelor could not only inhibit the platelet-induced migration of tumor cells with an invasive phenotype but also prevent tumor-platelet interaction. In vivo antitumor and antimetastasis results of this drug showed that CREKA-Ticagrelor could specifically target the tumor tissues within 24 h post intravenous injection and suppress lung metastasis. Meanwhile, by having this antiplatelet drug targeted, its side effects were minimized, and bleeding risk was decreased. Thus, CREKA-Ticagrelor offers an efficient antimetastatic agent.

Laparoscopic Surgery in the treatment of children with Choledochal Cyst.

OBJECTIVE: To evaluate the clinical effectiveness of laparoscopic surgery in the treatment of children with choledochal cyst. METHODS: Seventy-six children with congenital choledochal cyst who were admitted to our hospital between February 2016 and April 2017 were selected as research subjects. They were evenly divided into an observation group and a control group using random number table, 38 each group. Patients in the observation group underwent laparoscopic surgery, while patients in the control group underwent the traditional laparotomy. Surgery related indicators and prognosis were compared between the two groups. RESULTS: The incision size and intraoperative bleeding volume of the observation group were significantly smaller than those of the control group (P<0.05). The time of passage of flatus and time to take food of the observation group were easier than those of the control group, and the duration of hospitalization and parenteral nutrition of the former was significantly shorter than those of the latter, and the difference had statistical significance (P<0.05). The incidence of postoperative complications in the observation group was 2.6%, significantly lower than that in the control group (10.5%) (P<0.05). There was no recurrence in the observation group during the follow-up period, but there were 5 cases of recurrence (13.1%) in the control group; the difference was statistically significant (P<0.05). CONCLUSION: Compared with the traditional laparotomy, laparoscopic surgery conforms more to the concept of modern medical minimally invasive treatment and has a significant clinical effect in the treatment of congenital choledochal cyst in children. It can effectively promote the disappearance of clinical symptoms and signs, reduce the incidence of postoperative complications and disease recurrence, and improve the surgical efficacy, suggesting high clinical significance and application values.