Preparation and characterization of erythrocyte membrane cloaked PLGA/arsenic trioxide nanoparticles and evaluation of their in vitro anti-tumor effect

Homotypic cell membrane-camouflaged biomimetic PLGA nanoparticle loading triptolide for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-associated death worldwide. Beside early detection, early diagnosis, and early surgery, it is urgent to try new strategies for the treatment of HCC. Triptolide (TPL) has been employed to treat HCC. However, its clinical applications were restricted by the narrow therapeutic window, severe toxicity, and poor water-solubility. In this study, we developed cancer cell membrane-camouflaged biomimetic PLGA nanoparticles loading TPL (TPL@mPLGA) with the homologous targeting property for the treatment of HCC. The TPL@mPLGA was successfully prepared with particle size of 195.5 ± 7.5 nm and zeta potential at -21.5 ± 0.2 mV with good stability. The drug loading (DL) of TPL@mPLGA was 2.94%. After Huh-7 cell membrane coating, the natural Huh-7 cell membrane proteins were found to be retained on TPL@mPLGA, thus endowing the TPL@mPLGA with enhanced accumulation at tumor site, and better anti-tumor activity in vitro and in vivo when compared with TPL or TPL@PLGA. The TPL@mPLGA showed enhanced anti-tumor effects and reduced toxicity of TPL, which could be adopted for the treatment of HCC.

Maximizing arsenic trioxide's anticancer potential: Targeted nanocarriers for solid tumor therapy

Arsenic trioxide (ATO) has gained significant attention due to its promising therapeutic effects in treating different diseases, particularly acute promyelocytic leukemia (APL). Its potent anticancer mechanisms have been extensively studied. Despite the great efficacy ATO shows in fighting cancers, drawbacks in the clinical use are obvious, especially for solid tumors, which include rapid renal clearance and short half-life, severe adverse effects, and high toxicity to normal cells. Recently, the emergence of nanomedicine offers a potential solution to these limitations. The enhanced biocompatibility, excellent targeting capability, and desirable effectiveness have attracted much interest. Therefore, we summarized various nanocarriers for targeted delivery of ATO to solid tumors. We also provided detailed anticancer mechanisms of ATO in treating cancers, its clinical trials and shortcomings as well as the combination therapy of ATO and other chemotherapeutic agents for reduced drug resistance and synergistic effects. Finally, the future study direction and prospects were also presented.

Development and application of nanomaterials, nanotechnology and nanomedicine for treating hematological malignancies

Hematologic malignancies (HMs) pose a serious threat to patients' health and life, and the five-year overall survival of HMs remains low. The lack of understanding of the pathogenesis and the complex clinical symptoms brings immense challenges to the diagnosis and treatment of HMs. Traditional therapeutic strategies for HMs include radiotherapy, chemotherapy, targeted therapy and hematopoietic stem cell transplantation. Although immunotherapy and cell therapy have made considerable progress in the last decade, nearly half of patients still relapse or suffer from drug resistance. Recently, studies have emerged that nanomaterials, nanotechnology and nanomedicine show great promise in cancer therapy by enhancing drug targeting, reducing toxicity and side effects and boosting the immune response to promote durable immunological memory. In this review, we summarized the strategies of recently developed nanomaterials, nanotechnology and nanomedicines against HMs and then proposed emerging strategies for the future designment of nanomedicines to treat HMs based on urgent clinical needs and technological progress.

Development and evaluation of cell membrane-based biomimetic nanoparticles loaded by Clostridium perfringens epsilon toxin: a novel vaccine delivery platform for Clostridial-associated diseases

As Clostridium perfringens (C. perfringens) epsilon toxin (ETX) ranks as the third most potent clostridial toxin after botulinum and tetanus toxins, vaccination is necessary for creatures that can be affected by it to be safe from the effects of this toxin. Nowadays, nanostructures are good choices for carriers for biological environments. We aimed to synthesize biomimetic biodegradable nanodevices to enhance the efficiency of the ETX vaccine. For this purpose, poly(lactic-co-glycolic acid) (PLGA) copolymer loaded with purified epsilon protoxin (proETX) to create nanoparticles called nanotoxins (NTs) and then coated by RBC membrane-derived vesicles (RVs) to form epsilon nanotoxoids (RV-NTs). The resulting RV-NTs shaped smooth spherical surfaces with double-layer core/shell structure with an average particle size of 105.9 ± 35.1 nm and encapsulation efficiency of 97.5% ± 0.13%. Compared with NTs, the RV-NTs were more stable for 15 consecutive days. In addition, although both structures showed a long-term cumulative release, the release rates from RV-NTs were slower than NTs during 144 hours. According to the results of cell viability, ETX loading in PLGA and entrapment in the RBC membrane decreased the toxicity of the toxin. The presence of PLGA enhances the uptake of proETX, and the synthesized structures showed no significant lesion after injection. These results demonstrate that NTs and RV-NTs could serve as an effective vaccine platform to deliver ETX for future in vivo assays.

Biomimetic cell membrane-coated poly(lactic-co-glycolic acid) nanoparticles for biomedical applications

Poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) are commonly used for drug delivery because of their favored biocompatibility and suitability for sustained and controlled drug release. To prolong NP circulation time, enable target-specific drug delivery and overcome physiological barriers, NPs camouflaged in cell membranes have been developed and evaluated to improve drug delivery. Here, we discuss recent advances in cell membrane-coated PLGA NPs, their preparation methods, and their application to cancer therapy, management of inflammation, treatment of cardiovascular disease and control of infection. We address the current challenges and highlight future research directions needed for effective use of cell membrane-camouflaged NPs.

A practical strategy to subcutaneous administered in-situ gelling co-delivery system of arsenic and retinoic acid for the treatment of acute promyelocytic leukemia

Arsenic trioxide (ATO) combined with all trans retinoic acid (ATRA) is the first choice for the treatment of low and medium risk acute promyelocytic leukemia (APL). Clinical studies reported that the combination of ATO and ATRA could achieve a significant curative effect. However, the retinoic acid syndrome, serious drug resistance and the short half-life in vivo which lead to frequent and large dose administration limit the application of ATRA. In addition, the preparations of arsenic are conventional injections and tablets in clinic, which has poor patients' compliance caused by frequent long-term administration and serious side effects. In order to overcome the above limitations, a phospholipid phase separation gel (PPSG) loaded with ATO and ATRA was developed. ATO+ATRA-PPSG (AAP), as a biodegradable sustained-release delivery system, was the first achievement of co-delivery of hydrophilic ATO and lipophilic ATRA with high drug loading which is the main problem in the application of nano preparation. The prepared PPSG displayed high safety and biocompatibility. The drug in PPSG was released slowly and continuously in vivo and in vitro for up to 10 d, which could reduce the side effects caused by the fluctuation of blood drug concentration and solve the problem of the long treatment cycle and frequent administration. In vivo pharmacokinetics depicted that PPSG could improve the bioavailability, decrease the peak concentration, and prolong the t1/2 of ATO and ATRA. Particularly, AAP significantly inhibited the tumor volume, extended the survival period of tumor-bearing mice, and promoted the differentiation of APL cells into normal cells. Therefore, ATO+ATRA-PPSG not only could co-load hydrophilic ATO and lipophilic ATRA according to the clinical dosage, but also possessed the sustained-release and long-acting treatment effect which was expected to reduce administration time and ameliorate compliance of patients. Thus, it had great potential for clinical transformation and application.

Current status and future prospects of nanomedicine for arsenic trioxide delivery to solid tumors

Despite having a rich history as a poison, arsenic and its compounds have also gained a great reputation as promising anticancer drugs. As a pioneer, arsenic trioxide has been approved for the treatment of acute promyelocytic leukemia. Many in vitro studies suggested that arsenic trioxide could also be used in the treatment of solid tumors. However, the transition from bench to bedside turned out to be challenging, especially in terms of the drug bioavailability and concentration reaching tumor tissues. To address these issues, nanomedicine tools have been proposed. As nanocarriers of arsenic trioxide, various materials have been examined including liposomes, polymer, and inorganic nanoparticles, and many other materials. This review gives an overview of the existing strategies of delivery of arsenic trioxide in cancer treatment with a focus on the drug encapsulation approaches and medicinal impact in the treatment of solid tumors. It focuses on the progress in the last years and gives an outlook and suggestions for further improvements including theragnostic approaches and targeted delivery.

An efficient delivery of photosensitizers and hypoxic prodrugs for a tumor combination therapy by membrane camouflage nanoparticles

Photodynamic therapy (PDT) is an oxygen-dependent, non-invasive cancer treatment. The hypoxia in the tumor environment limits the therapeutic effects of PDT. The combined delivery of photosensitizers and hypoxic prodrugs is expected to improve the efficacy of tumor treatment. In this paper, an erythrocyte and tumor cell membrane camouflage nanocarrier co-loaded with a photosensitizer (indocyanine green) and a hypoxic prodrug (tirapazamine) were used to combine PDT with chemotherapy. The system achieved less macrophage clearance through erythrocyte membranes and tumor-targeted tumor cell membranes, thereby inducing cell death and increasing tumor environment hypoxia by NIR irradiation of photosensitizers. Furthermore, the hypoxic environment activated TPZ to kill more tumor cells. In vivo results showed that the tumor inhibition rate of the drug-loaded nanoparticles increased from 34% to 64% after membrane modification. Moreover, the tumor inhibition rate of the photodynamic treatment group alone was only 47%, and the tumor inhibition rate after the combination was 1.3 times that of photodynamic therapy alone. Our platform is expected to contribute to the further application of cancer combination therapy.

Basic Pharmacological Characterization of EV-34, a New H2S-Releasing Ibuprofen Derivative

BACKGROUND

Cardioprotective effects of H2S are being suggested by numerous studies. Furthermore, H2S plays a role in relaxation of vascular smooth muscle, protects against oxidative stress, and modulates inflammation. Long-term high-dose use of NSAIDs, such as ibuprofen, have been associated with enhanced cardiovascular risk. The goal of the present work is the synthesis and basic pharmacological characterization of a newly designed H2S-releasing ibuprofen derivative.

METHODS

Following the synthesis of EV-34, a new H2S-releasing derivative of ibuprofen, oxidative stability assays were performed (Fenton and porphyrin assays). Furthermore, stability of the molecule was studied in rat serum and liver lysates. H2S-releasing ability of the EC-34 was studied with a hydrogen sulfide sensor. MTT (3-(4,5-dimethylthiazol 2-yl)-2,5-(diphenyltetrazolium bromide)) assay was carried out to monitor the possible cytotoxic effect of the compound. Cyclooxygenase (COX) inhibitory property of EV-34 was also evaluated. Carrageenan assay was carried out to compare the anti-inflammatory effect of EV-34 to ibuprofen in rat paws.

RESULTS

The results revealed that the molecule is stable under oxidative condition of Fenton reaction. However, EV-34 undergoes biodegradation in rat serum and liver lysates. In cell culture medium H2S is being released from EV-34. No cytotoxic effect was observed at concentrations of 10, 100, 500 µM. The COX-1 and COX-2 inhibitory effects of the molecule are comparable to those of ibuprofen. Furthermore, based on the carrageenan assay, EV-34 exhibits the same anti-inflammatory effect to that of equimolar amount of ibuprofen (100 mg/bwkg).

CONCLUSION

The results indicate that EV-34 is a safe H2S releasing ibuprofen derivative bearing anti-inflammatory properties.

Hybrid red blood cell membrane coated porous silicon nanoparticles functionalized with cancer antigen induce depletion of T cells

Erythrocyte-based drug delivery systems have been investigated for their biocompatibility, long circulation time, and capability to transport cargo all around the body, thus presenting enormous potential in medical applications. In this study, we investigated hybrid nanoparticles consisting of nano-sized autologous or allogeneic red blood cell (RBC) membranes encapsulating porous silicon nanoparticles (PSi NPs). These NPs were functionalized with a model cancer antigen TRP2, which was either expressed on the surface of the RBCs by a cell membrane-mimicking block copolymer polydimethylsiloxane-b-poly-2-methyl-2-oxazoline, or attached on the PSi NPs, thus hidden within the encapsulation. When in the presence of peripheral blood immune cells, these NPs resulted in apoptotic cell death of T cells, where the NPs having TRP2 within the encapsulation led to a stronger T cell deletion. The deletion of the T cells did not change the relative proportion of CD4⁺ and cytotoxic CD8⁺ T cells. Overall, this work shows the combination of nano-sized RBCs, PSi, and antigenic peptides may have use in the treatment of autoimmune diseases.

We report a study on the effect of red blood cell membrane based cancer antigen-functionalized nanoparticles on peripheral blood T cells. These nanoparticles induce apoptosis of T cells and they may have use in treating autoimmune diseases.

Biomimetic nanoparticle loading obatoclax mesylate for the treatment of non-small-cell lung cancer (NSCLC) through suppressing Bcl-2 signaling

Lung cancer still remains a leading cause of cancer mortality in the world. Obatoclax mesylate (OM), a B cell chronic lymphocytic leukemia/lymphoma 2 (Bcl-2) family antagonist, is a potential antitumor drug. However, its poor aqueous solubility restricts its clinical application. Although these inherent defects, nanotechnology can be used to improve the solubility and tumor target of OM, promoting its antitumor efficiency. In the present study, the poly(lactic-coglycolic acid) (PLGA) was used and combined with red blood-cell membrane (RBCm) to explore if OM-loaded RBCm nanoparticles could improve the antitumor efficacy of OM for the treatment of lung cancer with relatively lower side effects compared with the free OM. The good physicochemical stability of the prepared RBCm-OM/PLGA nanoparticles was confirmed, and the optimal size of 153 nm was screened out, along with sustained drug release behavior. We found that RBCm-OM/PLGA nanoparticles effectively reduced the proliferation of lung cancer cells. Additionally, RBCm-OM/PLGA nanoparticles considerably induced apoptosis in lung cancer cells by reducing Bcl-2 expression levels, accompanied with the improved Cyto-c releases in cytoplasm and Caspase-3 activation. Mitochondrial membrane potential was also obviously impaired in lung cancer cells incubated with RBCm-OM/PLGA nanoparticles. Compared with free OM, RBCm-OM/PLGA nanoparticles could greatly prolong the drug circulation time in vivo and upgraded the drug concentration accumulated in tumor tissue. Furthermore, RBCm-OM/PLGA nanoparticles exerted stronger antitumor efficacy in vivo against lung cancer progression with superior safety. Therefore, RBCm-OM/PLGA nanoparticles provided new potential for lung cancer therapy with the improved safety and therapeutic effect.

Transcutaneous anaesthetic nano-enabled hydrogels for eyelid surgery

Local anaesthetics are administered as a diffuse superficial slow injection in blepharoplasty. Current transcutaneous local anaesthetic formulations are not licensed for use on the face due to safety concerns. Here we report for the first time the permeation of local anaesthetics (lidocaine, bupivacaine loaded SNEDDS and their hydrogels) across human eyelid and mouse skin as a novel and ocular safe formulation for eyelid surgery. SNEDDS were loaded with high levels of anaesthetics and incorporated within carbomer hydrogels to yield nano-enabled gels. Lidocaine hydrogels have a significantly reduced lag time compared to EMLA, while they enhance lidocaine flux across human eyelid skin by 5.2 fold. Ex vivo tape stripping experiments indicated localisation of anaesthetics within the stratum corneum and dermis. Initial histopathological studies have shown no apparent signs of skin irritation. These results highlight the potential clinical capability of nano-enabled anaesthetic hydrogels as a non-invasive anaesthetic procedure for eyelid surgery.

Integrin αvβ3 Receptor Overexpressing on Tumor-Targeted Positive MRI-Guided Chemotherapy

Multifunctional nanomaterials with targeted imaging and chemotherapy have high demand with great challenge. Herein, we rationally aimed to design multifunctional drug delivery systems by RGD-modified chitosan (CH)-coated nanoneedles (NDs) of gadolinium arsenate (RGD-CH-Gd-AsNDs). These NDs have multifunctionality for imaging and targeted therapy. NDs on intravenous administration demonstrated significant accumulation of As ions/species in tumor tissues, which was monitored by the change in T₁-weighted magnetic resonance (MR) imaging. Moreover, NDs were well opsonized in cells with high specificity, subsequently inducing apoptosis to the HepG2 cells. Consequent to this, the in vivo results demonstrated biosafety, enhanced tumor targeting, and tumor regression in a subcutaneously transplanted xenograft model in nude mice. These RGD-CH-Gd-AsNDs have great potential, and we anticipate that they could serve as a novel platform for real-time T₁-weighted MR diagnosis and chemotherapy.

Nanoerythrosomes tailoring: Lipid induced protein scaffolding in ghost membrane derived vesicles

A peculiar polygonal protein scaffolding that resembles to spectrin-based skeleton of red blood cells can be reconstructed on the outer surface of vesicle-like nanoerythrosomes. The approximately 130 nm sized nanoerythrosomes are produced from red blood cell ghosts by addition of phospholipids (dipalmitoylphosphatidylcholine, DPPC). The scaffolding, constructed from the structural proteins of the cell membrane skeleton, covers the whole object resulting an enhanced stiffness. The protein pattern of the scaffolding is thermosensitive, reversible transformable in the biologically relevant temperature range. When the lipid additive is changed from DPPC to lysophospholipid (LPC), the protein network/scaffolding ceases to exist. By the variation of lipid type and ratio, a tailoring of the nanoerythrosomes can be achieved. During the tailoring process nanoerythrosomes or micelles, in a wide size range from 200 to 30 nm, are produced.

Beyond Cisplatin: Combination Therapy with Arsenic Trioxide

Platinum drugs (cisplatin, oxaliplatin, and carboplatin) and arsenic trioxide are the only commercial inorganic non-radioactive anticancer drugs approved by the US Food and Drug Administration. Numerous efforts are underway to take advantage of the synergy between the anticancer activity of cisplatin and arsenic trioxide - two drugs with strikingly different mechanisms of action. These include co-encapsulation of the two drugs in novel nanoscale delivery systems as well as the development of small molecule agents that combine the activity of these two inorganic materials. Several of these new molecular entities containing Pt-As bonds have broad anticancer activity, are robust in physiological buffer solutions, and form stable complexes with biopolymers. This review summarizes results from a number of preclinical studies involving the combination of cisplatin and As2O3, co-encapsulation and nanoformulation efforts, and the chemistry and cytotoxicity of the first member of platinum anticancer agents with an arsenous acid moiety bound to the platinum(II) center: arsenoplatins.

Targeted arsenite-loaded magnetic multifunctional nanoparticles for treatment of hepatocellular carcinoma

Arsenic trioxide (ATO), an FDA-approved drug for acute promyelocytic leukemia, also has great potential for treatment of solid tumors. Drug delivery powered by recent advances in nanotechnology has boosted the efficacy of many drugs, which is enlightening for applications of ATO in treating solid tumors. Herein, we reported arsenite-loaded multifunctional nanoparticles that are capable of pH-responsive ATO release for treating hepatocellular carcinoma (HCC) and real-time monitoring via magnetic resonance imaging. We fabricated these nanoparticles (designated as magnetic large-pore mesoporous silica nanoparticle (M-LPMSN)-NiAsO _x ) by loading nanoparticulate ATO prodrugs (NiAsO _x ) into the pores of large-pore mesoporous silica nanoparticles (LPMSNs) that contain magnetic iron oxide nanoparticles in the center. The surface of these nanodrugs was modified with a targeting ligand folic acid (FA) to further enhance the drug efficacy. Releasing profiles manifest the responsive discharging of arsenite in acidic environment. In vitro experiments with SMMC-7721 cells reveal that M-LPMSN-NiAsO _x -FA nanodrugs have significantly higher cytotoxicity than traditional free ATO and induce more cell apoptosis. In vivo experiments with mice bearing H22 tumors further confirm the superior antitumor efficacy of M-LPMSN-NiAsO _x -FA over traditional free ATO and demonstrate the outstanding imaging ability of M-LPMSN-NiAsO _x -FA for real-time tumor monitoring. These targeted arsenite-loaded magnetic mesoporous silica nanoparticles integrating imaging and therapy hold great promise for treatment of HCC, indicating the auspicious potential of LPMSN-based nanoplatforms.