Profiling target engagement and cellular uptake of cRGD-decorated clinical-stage core-crosslinked polymeric micelles.

Polymeric micelles are increasingly explored for tumor-targeted drug delivery. CriPec® technology enables the generation of core-crosslinked polymeric micelles (CCPMs) based on thermosensitive (mPEG-b-pHPMAmLacn) block copolymers, with high drug loading capacity, tailorable size, and controlled drug release kinetics. In this study, we decorated clinical-stage CCPM with the αvß3 integrin-targeted cyclic arginine-glycine-aspartic acid (cRGD) peptide, which is one of the most well-known active targeting ligands evaluated preclinically and clinically. Using a panel of cell lines with different expression levels of the αvß3 integrin receptor and exploring both static and dynamic incubation conditions, we studied the benefit of decorating CCPM with different densities of cRGD. We show that incubation time and temperature, as well as the expression levels of αvß3 integrin by target cells, positively influence cRGD-CCPM uptake, as demonstated by immunofluorescence staining and fluorescence microscopy. We demonstrate that even very low decoration densities (i.e., 1 mol % cRGD) result in increased engagement and uptake by target cells as compared to peptide-free control CCPM, and that high cRGD decoration densities do not result in a proportional increase in internalization. In this context, it should be kept in mind that a more extensive presence of targeting ligands on the surface of nanomedicines may affect their pharmacokinetic and biodistribution profile. Thus, we suggest a relatively low cRGD decoration density as most suitable for in vivo application.

Modification of erythrocytes by internalizing Arg-Gly-Asp (iRGD) in boosting the curative effect of radiotherapy for gastric carcinoma.

Background: Radiation resistance remains the leading cause of radiotherapy (RT) failure. The development of tumor-specific targeted sensitizers is key to overcoming radiation resistance. Our early data showed that cancer cell penetration was simulated by internalizing arginine-glycine-aspartic acid (iRGD), and the irradiation efficacy was improved. The present study aims to design and fabricate iRGD-modified red blood cell (RBCs) for tumor targeting and RT enhancement, and to evaluate its safety and efficacy in vivo. Methods: 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-poly ethylene glycol-iRGD (DSPE-PEG-iRGD) was used to modify RBCs by a lipid-insertion method without direct chemical bioconjugation. Fluorescent dyes were used to trace the functional RBCs through confocal microscopy examination. In vitro stability evaluation was performed using cell culture medium incubation for 48 h followed by fluorescence decay assay. Furthermore, a subcutaneous cancer cell mouse model was constructed with MKN-45 cells for target efficacy and RT enhancement evaluation with DSPE-PEG-iRGD-modified RBCs (RBC-iRGD). Results: Successful construction of RBC-iRGD was verified by the presence of the yellow fluorescence, and an approximately 108 iRGD molecules were labeled on a single RBC. The final RBC-iRGD showed good stability without any hemolytic effects in the cell culture medium. Moreover, higher fluorescence intensity and decreased liver and spleen accumulation could be observed in RBC-iRGD compared to RBC + iRGD in vivo. The RBC-iRGD exerted enhanced radiosensitivity in subcutaneous gastric tumor mice. Conclusions: The RBC-iRGD exerted good tumor-targeting efficacy and favorable effects for RT enhancement in vivo.

Substrate adhesion determines migration during mesenchymal cell condensation in chondrogenesis.

Mesenchymal condensation is a prevalent morphogenetic transition that is essential in chondrogenesis. However, the current understanding of condensation mechanisms is limited. In vivo, progenitor cells directionally migrate from the surrounding loose mesenchyme towards regions of increasing matrix adherence (the condensation centers), which is accompanied by the upregulation of fibronectin. Here, we focused on the mechanisms of cell migration during mesenchymal cell condensation and the effects of matrix adherence. Dendrimer-based nanopatterns of the cell-adhesive peptide arginine-glycine-aspartic acid (RGD), which is present in fibronectin, were used to regulate substrate adhesion. We recorded collective and single-cell migration of mesenchymal stem cells, under chondrogenic induction, using live-cell imaging. Our results show that the cell migration mode of single cells depends on substrate adhesiveness, and that cell directionality controls cell condensation and the fusion of condensates. Inhibition experiments revealed that cell-cell interactions mediated by N-cadherin (also known as CDH2) are also pivotal for directional migration of cell condensates by maintaining cell-cell cohesion, thus suggesting a fine interplay between cell-matrix and cell-cell adhesions. Our results shed light on the role of cell interactions with a fibronectin-depositing matrix during chondrogenesis in vitro, with possible applications in regenerative medicine. This article has an associated First Person interview with the first author of the paper.

Combined 18F-FDG and 18F-Alfatide II PET May Predict Luminal B (HER2 Negative) Subtype and Nonluminal Subtype of Invasive Breast Cancer.

Noninvasive PET molecular imaging using radiopharmaceuticals is important to classify breast cancer in the clinic. The aim of this study was to investigate the combination of 18F-FDG and 18F-Alfatide II for predicting molecular subtypes of invasive breast cancer. Forty-four female patients with clinically suspected breast cancer were recruited and underwent 18F-FDG and 18F-Alfatide II PET/CT within a week. Tracer uptake in breast lesions was assessed using the maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), and SUVmax ratio of 18F-FDG to 18F-Alfatide II (FAR). Invasive breast cancer lesions were further classified as luminal A subtype, luminal B subtype, human epidermal growth factor receptor-2 (HER2) overexpressing subtype, and triple negative subtype according to the expression of the estrogen receptor (ER), progesterone receptor (PR), HER2, and Ki-67. Among 44 patients, 35 patients were pathologically diagnosed with invasive breast cancer. The SUVmax and SUVmean of 18F-FDG were significantly higher in the ER-negative group than those in the ER-positive group, as well as in the PR-negative group than those in the PR-positive group. However, the SUVmax and SUVmean of 18F-Alfatide II were higher in the ER-positive group and the PR-positive group. By combining 18F-FDG and 18F-Alfatide II, the FAR was lower in the ER-positive group and the PR-positive group. The HER2 overexpressing subtype showed the highest SUVmax and SUVmean for 18F-FDG while the luminal B (HER2 negative) subtype revealed the lowest values. The luminal B (HER2 negative) subtype showed the highest 18F-Alfatide II SUVmax, while the triple negative subtype showed the lowest 18F-Alfatide II SUVmax. The FAR was the lowest in the luminal B (HER2 negative) subtype and much higher in the HER2 overexpressing and triple negative subtypes. FAR less than 1 predicted the luminal B (HER2 negative) subtype with high specificity (93.1%) and NPV (90%). FAR greater than 3 predicted the HER2 overexpressing subtype and triple negative subtype (namely, the nonluminal subtype) with very high specificity (100%) and PPV (100%). In summary, FAR, the combined PET parameter of 18F-FDG and 18F-Alfatide II, can be used to predict molecular subtypes of invasive breast cancer, especially for the luminal B (HER2 negative) subtype and the nonluminal subtype.

Usefulness of 18F-FPP-RGD2 PET in pathophysiological evaluation of lung fibrosis using a bleomycin-induced rat model.

PURPOSE: Integrins αv are key molecules in the pathogenesis of fibrosis in multiple organs. To assess the potential utility of integrin αvß3 imaging for idiopathic pulmonary fibrosis (IPF), we evaluated an 18F-FPP-RGD2 PET probe in a rat model of bleomycin-induced lung fibrosis. METHODS: Pulmonary fibrosis was induced by single intratracheal instillation of bleomycin (3 mg/rat). Positron emission tomography (PET)/computerized tomography scans were performed 4 weeks after bleomycin administration using 18F-FPP-RGD2. Total distribution volume (VT) was estimated using one-tissue/two-compartment, two-tissue/three-compartment models, and Logan graphical analysis (Logan plot; t* = 30 min). Plasma-free fractions were estimated from images of the left ventricle. Correlation between Logan VT and lung pathology was assessed by Spearman's rank correlation. RESULTS: Histopathological evaluation demonstrated the development of fibrosis in IPF-model group. Integrin αv protein expression and lung radioactivity were higher in IPF-model group compared with control group. The lung radioactivity of 18F-FPP-RGD2 rapidly reached the peak after administration and then gradually decreased, whereas left ventricular radioactivity rapidly disappeared. Logan graphical analysis was found to be suitable for 18F-FPP-RGD2 kinetic analysis in the IPF-model lung. Logan VT values for 18F-FPP-RGD2 were significantly higher in IPF rats compared with control rats and strongly correlated with lung fibrosis, pathology, integrin αv protein expression, and oxygen partial pressure. CONCLUSION: Our findings demonstrate that the integrin αvß3 PET probe 18F-FPP-RGD2 can detect pathophysiological changes in lungs, including fibrosis accompanying upregulated integrin αv of IPF-model rats. These findings support the utility of 18F-FPP-RGD2 PET imaging for the pathophysiological evaluation of pulmonary fibrosis.

Nanoscale ligand density modulates gap junction intercellular communication of cell condensates during chondrogenesis.

Aim: To unveil the influence of cell-matrix adhesions in the establishment of gap junction intercellular communication (GJIC) during cell condensation in chondrogenesis. Materials & methods: Previously developed nanopatterns of the cell adhesive ligand arginine-glycine-aspartic acid were used as cell culture substrates to control cell adhesion at the nanoscale. In vitro chondrogenesis of mesenchymal stem cells was conducted on the nanopatterns. Cohesion and GJIC were evaluated in cell condensates. Results: Mechanical stability and GJIC are enhanced by a nanopattern configuration in which 90% of the surface area presents adhesion sites separated less than 70 nm, thus providing an onset for cell signaling. Conclusion: Cell-matrix adhesions regulate GJIC of mesenchymal cell condensates during in vitro chondrogenesis from a threshold configuration at the nanoscale.

Advanced application of stimuli-responsive drug delivery system for inflammatory arthritis treatment.

Inflammatory arthritis is a major cause of disability in the elderly. This condition causes joint pain, loss of function, and deterioration of quality of life, mainly due to osteoarthritis (OA) and rheumatoid arthritis (RA). Currently, available treatment options for inflammatory arthritis include anti-inflammatory medications administered via oral, topical, or intra-articular routes, surgery, and physical rehabilitation. Novel alternative approaches to managing inflammatory arthritis, so far, remain the grand challenge owing to catastrophic financial burden and insignificant therapeutic benefit. In the view of non-targeted systemic cytotoxicity and limited bioavailability of drug therapies, a major concern is to establish stimuli-responsive drug delivery systems using nanomaterials with on-off switching potential for biomedical applications. This review summarizes the advanced applications of triggerable nanomaterials dependent on various internal stimuli (including reduction-oxidation (redox), pH, and enzymes) and external stimuli (including temperature, ultrasound (US), magnetic, photo, voltage, and mechanical friction). The review also explores the progress and challenges with the use of stimuli-responsive nanomaterials to manage inflammatory arthritis based on pathological changes, including cartilage degeneration, synovitis, and subchondral bone destruction. Exposure to appropriate stimuli induced by such histopathological alterations can trigger the release of therapeutic medications, imperative in the joint-targeted treatment of inflammatory arthritis.

Luminescent gold-peptide spheric aggregates: selective and effective cellular targeting.

Although the restriction of intramolecular motion has been well recognized as the fundamental of aggregation induced emission enhancement (AIEE), the regulation mechanism of gold nanoclusters (AuNCs) based AIEE system are still unclear. In this paper, we have investigated the Zn2+-induced AIEE process of thiolate ligands (i.e., cysteine, glutathione and an 8-mer peptide) protected AuNCs, which shows a pH-dependent evolution from single AuNCs to spheric aggregates to irregular network. Using photoluminescent enhancement ratio as an index, the concept of "mid-pH" is proposed to indicate the optimal pH for the formation of spheric AuNCs aggregates. Importantly, the surface ligands allow the formation of spheric AuNCs aggregates at tunable mid-pH between 5.7 and 7.5. Owing to the appropriate size and surface peptide targetability, the spheric AuNCs aggregates can be successfully screened for targeted tumor cell uptake and imaging at physiological pH. The cell uptake mechanism study showed that AuNCs aggregates was specifically recognized by arginine-glycine-aspartic acid (RGD) sequence on the ligand and integrin αvß3 on the cell surface, thus mainly through clathrin-mediated endocytosis. This work provides new sight to artificially regulate the construction of efficient cellular imaging probes.

Transforming growth factor ß latency: A mechanism of cytokine storage and signalling regulation in liver homeostasis and disease.

Transforming growth factor-ß (TGF-ß) is a potent effector in the liver, which is involved in a plethora of processes initiated upon liver injury. TGF-ß affects parenchymal, non-parenchymal, and inflammatory cells in a highly context-dependent manner. Its bioavailability is critical for a fast response to various insults. In the liver - and probably in other organs - this is made possible by the deposition of a large portion of TGF-ß in the extracellular matrix as an inactivated precursor form termed latent TGF-ß (L-TGF-ß). Several matrisomal proteins participate in matrix deposition, latent complex stabilisation, and activation of L-TGF-ß. Extracellular matrix protein 1 (ECM1) was recently identified as a critical factor in maintaining the latency of deposited L-TGF-ß in the healthy liver. Indeed, its depletion causes spontaneous TGF-ß signalling activation with deleterious effects on liver architecture and function. This review article presents the current knowledge on intracellular L-TGF-ß complex formation, secretion, matrix deposition, and activation and describes the proteins and processes involved. Further, we emphasise the therapeutic potential of toning down L-TGF-ß activation in liver fibrosis and liver cancer.

Extracellular cathepsin Z signals through the α5 integrin and augments NLRP3 inflammasome activation.

Respiratory silicosis is a preventable occupational disease that develops secondary to the aspiration of crystalline silicon dioxide (silica) into the lungs, activation of the NLRP3 inflammasome, and IL-1ß production. Cathepsin Z has been associated with the development of inflammation and IL-1ß production; however, the mechanism of how cathepsin Z leads to IL-1ß production is unknown. Here, the requirement for cathepsin Z in silicosis was determined using WT mice and mice deficient in cathepsin Z. The activation of the NLRP3 inflammasome in macrophages was studied using WT and cathepsin Z-deficient bone marrow-derived murine dendritic cells and the human monocytic cell line THP-1. The cells were activated with silica, and IL-1ß release was determined using enzyme-linked immunosorbent assay or IL-1ß bioassays. The relative contribution of the active domain or integrin-binding domain of cathepsin Z was studied using recombinant cathepsin Z constructs and the α5 integrin neutralizing antibody. We report that the lysosomal cysteine protease cathepsin Z potentiates the development of inflammation associated with respiratory silicosis by augmenting NLRP3 inflammasome-derived IL-1ß expression in response to silica. The secreted cathepsin Z functions nonproteolytically via the internal integrin-binding domain to impact caspase-1 activation and the production of active IL-1ß through integrin α5 without affecting the transcription levels of NLRP3 inflammasome components. This work reveals a regulatory pathway for the NLRP3 inflammasome that occurs in an outside-in fashion and provides a link between extracellular cathepsin Z and inflammation. Furthermore, it reveals a level of NLRP3 inflammasome regulation that has previously only been found downstream of extracellular pathogens.

Preliminary study on 99Tc m-3PRGD 2 imaging to verify the anti-angiogenesis mechanism and efficacy of Mongolian medicine Sendeng-4 decoction for rheumatoid arthritis / 中华核医学与分子影像杂志

Objective:To explore the therapeutic mechanism of Mongolian medicine Sendeng-4 decoction for rheumatoid arthritis by 99Tc m-hydrazinonicotinamide-(polyethylene glycol) 4-E[(polyethylene glycol) 4-c((Arg-Gly-Asp)fk)] 2 (3PRGD 2) imaging. Methods:A total of 200 female SD rats (age: 6-7 weeks) were divided into collagen-induced arthritis (CIA) group ( n=176) and blank control group ( n=24). Rats in the CIA group were divided into Sendeng-4 decoction treatment group ( n=24), etanercept treatment group ( n=24), and negative control group ( n=24) by simple random sampling method. 99Tc m-3PRGD 2 SPECT/CT imaging was performed before and after modeling and treatment. The differences of target/non-target (T/NT) ratio and serological, pathological, and immunohistochemical results among groups were compared by one-way analysis of variance or Kruskal-Wallis rank sum test. The correlation was analyzed by Pearson correlation or Spearman correlation analysis. Results:There were 95 (95/176) CIA models successfully established. The T/NT ratios of Sendeng-4 decoction treatment group and etanercept treatment group were lower than that of negative control group (0.260± 0.094, 0.238±0.099, 0.766±0.144 ; F=163.00, P<0.001), while there was no significant difference between the two drug treatment groups ( P>0.05). After drug treatment, serum levels of vascular endothelial growth factor (VEGF), tumor necrosis factor-α (TNF-α) and α vβ 3 were significantly lower than those of negative control group ( F values: 49.43-92.36, all P<0.001), pathological score was also lower than that of negative control group ( H=34.25, P<0.001), and levels of immunohistochemical makers (VEGF, TNF-α, α vβ 3, CD31, CD34) were also lower than those of negative control group ( H values: 13.51-26.84, all P<0.001), while there were no significant differences between the two drug treatment groups (all P>0.05). The T/NT ratios were positively correlated with above indictors in Sendeng-4 decoction treatment group ( r values: 0.56-0.59, rs values: 0.49-0.69), etanercept treatment group ( r values: 0.50-0.55, rs values: 0.46-0.70) and negative control group ( r values: 0.55-0.80, rs values: 0.58-0.86, P<0.001 or P<0.05). Conclusion:Verified by 99Tc m-3PRGD 2 SPECT/CT imaging and molecular pathology, Mongolian medicine Sendeng-4 decoction can inhibit neovascularization by down-regulating vascular factors such as VEGF, resulting in delaying the progression of the disease and improving clinical symptoms.

Prediction of pathological complete response to neoadjuvant chemotherapy in breast cancer using 99Tc m-3PRGD 2 imaging in comparison to 18F-FDG imaging / 中华核医学与分子影像杂志

Objective:To evaluate the value of 99Tc m-hydrazinonicotinamide-(poly-(ethylene glycol)) 4-E((poly-(ethylene glycol)) 4-c((Arg-Gly-Asp)fK)) 2 (3PRGD 2) imaging on predicting pathological complete response (pCR) outcomes to neoadjuvant chemotherapy (NAC) in patients with breast cancer and to compare it with 18F-FDG imaging. Methods:From October 2017 to October 2019, 41 patients (age: (61.5±7.8) years) who were diagnosed with stage Ⅱ and Ⅲ breast cancer and planned to receive preoperative NAC in the First Affiliated Hospital of Fujian Medical University and Xiehe Affiliated Hospital of Fujian Medical University were prospectively enrolled. All patients underwent both 99Tc m-3PRGD 2 and 18F-FDG imaging before NAC (baseline), and after the first and the fourth NAC cycle. The tumor/background ratio (T/B; 99Tc m-3PRGD 2) and SUV max ( 18F-FDG) in breast tumors and axillary lymph node (ALN) metastases were separately calculated. The relative T/B changes (ΔT/B 1, ΔT/B 2) and SUV max changes (ΔSUV max1, ΔSUV max2) after the first and the fourth NAC cycle compared to baseline were obtained. Patients underwent surgery after NAC and the pathology was used as the gold standard to determine whether patient achieved pCR. The predictive performance of ΔT/B and ΔSUV max regarding the identification of pCR or non-pCR was evaluated by using ROC analysis and the AUCs were compared by Delong test. Results:Of 41 patients, 13 (31.7%) were achieved pCR after NAC. For breast tumors, the AUCs of ΔT/B 1, ΔT/B 2, ΔSUV max1 and ΔSUV max2 were 0.827 ( P=0.001), 0.687 ( P=0.057), 0.859 ( P<0.001) and 0.713 ( P=0.030) respectively, and the AUCs of ΔT/B 1 and ΔSUV max1 had no significant difference ( z=0.33, P=0.740). For ALN metastases, the AUCs of ΔT/B 1, ΔT/B 2, ΔSUV max1 and ΔSUV max2 were 0.859 ( P=0.002), 0.778 ( P=0.014), 0.572 ( P=0.523) and 0.802 ( P=0.007) respectively, and the AUC of ΔT/B 1 was significantly higher than that of ΔSUV max1 ( z=2.10, P=0.035). Conclusion:The early relative changes of breast tumors and ALN metastases in 99Tc m-3PRGD 2 imaging during NAC can offer predictive information for pCR to NAC in patients with breast cancer, and early relative changes of ALN metastases in 99Tc m-3PRGD 2 imaging may have a higher predictive value for pCR than 18F-FDG imaging.

Application of Quality by Design to the robust preparation of a liposomal GLA formulation by DELOS-susp method.

Fabry disease is a lysosomal storage disease arising from a deficiency of the enzyme α-galactosidase A (GLA). The enzyme deficiency results in an accumulation of glycolipids, which over time, leads to cardiovascular, cerebrovascular, and renal disease, ultimately leading to death in the fourth or fifth decade of life. Currently, lysosomal storage disorders are treated by enzyme replacement therapy (ERT) through the direct administration of the missing enzyme to the patients. In view of their advantages as drug delivery systems, liposomes are increasingly being researched and utilized in the pharmaceutical, food and cosmetic industries, but one of the main barriers to market is their scalability. Depressurization of an Expanded Liquid Organic Solution into aqueous solution (DELOS-susp) is a compressed fluid-based method that allows the reproducible and scalable production of nanovesicular systems with remarkable physicochemical characteristics, in terms of homogeneity, morphology, and particle size. The objective of this work was to optimize and reach a suitable formulation for in vivo preclinical studies by implementing a Quality by Design (QbD) approach, a methodology recommended by the FDA and the EMA to develop robust drug manufacturing and control methods, to the preparation of α-galactosidase-loaded nanoliposomes (nanoGLA) for the treatment of Fabry disease. Through a risk analysis and a Design of Experiments (DoE), we obtained the Design Space in which GLA concentration and lipid concentration were found as critical parameters for achieving a stable nanoformulation. This Design Space allowed the optimization of the process to produce a nanoformulation suitable for in vivo preclinical testing.

Long non-coding RNAs: From disease code to drug role.

Enormous studies have corroborated that long non-coding RNAs (lncRNAs) extensively participate in crucial physiological processes such as metabolism and immunity, and are closely related to the occurrence and development of tumors, cardiovascular diseases, nervous system disorders, nephropathy, and other diseases. The application of lncRNAs as biomarkers or intervention targets can provide new insights into the diagnosis and treatment of diseases. This paper has focused on the emerging research into lncRNAs as pharmacological targets and has reviewed the transition of lncRNAs from the role of disease coding to acting as drug candidates, including the current status and progress in preclinical research. Cutting-edge strategies for lncRNA modulation have been summarized, including the sources of lncRNA-related drugs, such as genetic technology and small-molecule compounds, and related delivery methods. The current progress of clinical trials of lncRNA-targeting drugs is also discussed. This information will form a latest updated reference for research and development of lncRNA-based drugs.

Phase 1 Study of THR-687, a Novel, Highly Potent Integrin Antagonist for the Treatment of Diabetic Macular Edema.

Purpose: To evaluate the safety and preliminary efficacy of THR-687 in patients with center-involved diabetic macular edema (DME). Design: Phase 1, open-label, multicenter, 3 + 3 dose-escalation study with 3-month follow-up. Participants: Patients 18 years of age or older with visual impairment resulting from DME. Methods: Single intravitreal injection of THR-687 (0.4 mg, 1.0 mg, or 2.5 mg). Main Outcome Measures: The primary outcome measure was the incidence of dose-limiting toxicities (DLTs). The secondary outcome measure was the incidence of adverse events (AEs), including the occurrence of laboratory abnormalities. Exploratory outcome measures included changes from baseline in best-corrected visual acuity (BCVA) and central subfield thickness (CST), assessments of ischemia and leakage on fluorescein angiography, and THR-687 levels in plasma. Results: Twelve patients were treated: 3 patients received 0.4 mg of THR-687, 3 patients received 1.0 mg of THR-687, and 6 patients received 2.5 mg of THR-687. Most patients were men (9/12 patients). Their mean age was 57.8 years. No DLTs or serious AEs were reported at any of the dose levels tested. Overall, 9 AEs in the study eye were reported for 5 of 12 patients. Of those, 4 AEs in 3 of 12 patients were deemed treatment related by the investigator, all of which were mild, started on the day of the injection, and had resolved within 28 days without treatment. Overall, mean gains from baseline in BCVA were observed at all study visits with a rapid onset (7.2 Early Treatment Diabetic Retinopathy Study [ETDRS] letters at day 7) and a durability up to the end of the study (8.3 ETDRS letters at month 3). A mean decrease in CST was observed up to month 1. Overall, the mean BCVA gains and CST decreases were highest at the highest THR-687 dose level tested. THR-687 was undetectable in plasma at 7 days after the injection. Conclusions: At all dose levels tested, a single intravitreal injection of THR-687 was safe and well tolerated. Preliminary efficacy was observed by a rapid gain in BCVA with 3 months' durability and a decrease in CST up to 1 month after the injection.

Dual-targeting nanovesicles enhance specificity to dynamic tumor cells in vitro and in vivo via manipulation of αvß3-ligand binding.

The dynamic or flowing tumor cells just as leukemia cells and circulating tumor cells face a microenvironment difference from the solid tumors, and the related targeting nanomedicines are rarely reported. The existence of fluidic shear stress in blood circulation seems not favorable for the binding of ligand modified nanodrugs with their target receptor. Namely, the binding feature is very essential in this case. Herein, we utilized HSPC, PEG-DSPE, cholesterol and two αvß3 ligands (RGDm7 and DT4) with different binding rates to build dual-targeting nanovesicles, in an effort to achieve a "fast-binding/slow-unbinding" function. It was demonstrated that the dual-targeting nanovesicles actualized efficient cellular uptake and antitumor effect in vitro both for static and dynamic tumor cells. Besides, the potency of the dual-targeting vesicles for flowing tumor cells was better than that for static tumor cells. Then, a tumor metastasis mice model and a leukemia mice model were established to detect the killing ability of the drug-loaded dual-targeting vesicles to dynamic tumor cells in vivo. The therapy efficacy of the dual-targeting system was higher than other controls including single-targeting ones. Generally, it seems possible to strengthen drug-targeting to dynamic tumor cells via the control of ligand-receptor interaction.

Recent advances in screening active components from natural products based on bioaffinity techniques.

Natural products have provided numerous lead compounds for drug discovery. However, the traditional analytical methods cannot detect most of these active components, especially at their usual low concentrations, from complex natural products. Herein, we reviewed the recent technological advances (2015-2019) related to the separation and screening bioactive components from natural resources, especially the emerging screening methods based on the bioaffinity techniques, including biological chromatography, affinity electrophoresis, affinity mass spectroscopy, and the latest magnetic and optical methods. These screening methods are uniquely advanced compared to other traditional methods, and they can fish out the active components from complex natural products because of the affinity between target and components, without tedious separation works. Therefore, these new tools can reduce the time and cost of the drug discovery process and accelerate the development of more effective and better-targeted therapeutic agents.

Quantitative evaluation of hepatic integrin αvß3 expression by positron emission tomography imaging using 18F-FPP-RGD2 in rats with non-alcoholic steatohepatitis.

BACKGROUND: Integrin αvß3, which are expressed by activated hepatic stellate cells in non-alcoholic steatohepatitis (NASH), play an important role in the fibrosis. Recently, we reported that an RGD peptide positron emission tomography (PET) probe is useful as a predictor of hepatic fibrosis. Kinetic analysis of the RGD PET probe has been performed in tumours, but not in hepatic fibrosis. Therefore, we aimed to quantify hepatic integrin αvß3 in a model of NASH by kinetic analysis using 18F-FPP-RGD2, an integrin αvß3 PET probe. METHODS: 18F-FPP-RGD2 PET/CT scans were performed in control and NASH rats. Tissue kinetic analyses were performed using a one-tissue, two-compartment (1T2C) and a two-tissue, three-compartment (2T3C) model using an image-derived input function (IDIF) for the left ventricle. We then conducted correlation analysis between standard uptake values (SUVs) or volume of distribution (VT), evaluated using compartment kinetic analysis and integrin αv or ß3 protein expression. RESULTS: Biochemical and histological evaluation confirmed the development of NASH rats. Integrin αvß3 protein expression and hepatic SUV were higher in NASH- than normal rats. The hepatic activity of 18F-FPP-RGD2 peaked rapidly after administration and then gradually decreased, whereas left ventricular activity rapidly disappeared. The 2T3C model was found to be preferable for 18F-FPP-RGD2 kinetic analysis in the liver. The VT (IDIF) for 18F-FPP-RGD2, calculated using the 2T3C model, was significantly higher in NASH- than normal rats and correlated strongly with hepatic integrin αv and ß3 protein expression. The strengths of these correlations were similar to those between SUV60-90 min and hepatic integrin αv or ß3 protein expression. CONCLUSIONS: We have demonstrated that the VT (IDIF) of 18F-FPP-RGD2, calculated using kinetic modelling, positively correlates with integrin αv and ß3 protein in the liver of NASH rats. These findings suggest that hepatic VT (IDIF) provides a quantitative assessment of integrin αvß3 protein in liver.

Dynamic Regulation of SARS-Cov-2 Binding and Cell Entry Mechanisms in Remodeled Human Ventricular Myocardium.

Using serial analysis of myocardial gene expression employing endomyocardial biopsy starting material in a dilated cardiomyopathy cohort, we show that mRNA expression of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) cardiac myocyte receptor ACE2 is up-regulated with remodeling and with reverse remodeling down-regulates into the normal range. The proteases responsible for virus-cell membrane fusion were expressed but not regulated with remodeling. In addition, a new candidate for SARS-CoV-2 cell binding and entry was identified, the integrin encoded by ITGA5. Up-regulation in ACE2 in remodeled left ventricles may explain worse outcomes in patients with coronavirus disease 2019 who have underlying myocardial disorders, and counteracting ACE2 up-regulation is a possible therapeutic approach to minimizing cardiac damage.

RGD-decorated solid lipid nanoparticles enhance tumor targeting, penetration and anticancer effect of asiatic acid.

Aim: Asiatic acid (AA) is a promising anticancer agent, however, its delivery to glioblastoma is a major challenge. This work investigates the beneficial therapeutic efficacy of RGD-conjugated solid lipid nanoparticles (RGD-SLNs) for the selective targeting of AA to gliblastoma. Materials & methods: AA-containing RGD-SLNs were prepared using two different PEG-linker size. Targetability and efficacy were tested using monolayer cells and spheroid tumor models. Results: RGD-SLNs significantly improved cytotoxicity of AA against U87-MG monolayer cells and enhanced cellular uptake compared with non-RGD-containing SLNs. In spheroid models, AA-containing RGD-SLNs showed superior control in tumor growth, improved cytotoxicity and enhanced spheroid penetration when compared with AA alone or non-RGD-containing SLNs. Conclusion: This study illustrates the potential of AA-loaded RGD-SLNs as efficacious target-specific treatment for glioblastoma.