Advanced therapeutic approach for the treatment of malignant pleural mesothelioma via the intrapleural administration of liposomal pemetrexed

Three-dimensional printing of the human lung pleural cavity model for PDT malignant mesothelioma

OBJECTIVE

The primary aim was to investigate emerging 3D printing and optical acquisition technologies to refine and enhance photodynamic therapy (PDT) dosimetry in the management of malignant pleural mesothelioma (MPM).

MATERIALS AND METHODS

A rigorous digital reconstruction of the pleural lung cavity was conducted utilizing 3D printing and optical scanning methodologies. These reconstructions were systematically assessed against CT-derived data to ascertain their accuracy in representing critical anatomic features and post-resection topographical variations.

RESULTS

The resulting reconstructions excelled in their anatomical precision, proving instrumental translation for precise dosimetry calculations for PDT. Validation against CT data confirmed the utility of these models not only for enhancing therapeutic planning but also as critical tools for educational and calibration purposes.

CONCLUSION

The research outlined a successful protocol for the precise calculation of light distribution within the complex environment of the pleural cavity, marking a substantive advance in the application of PDT for MPM. This work holds significant promise for individualizing patient care, minimizing collateral radiation exposure, and improving the overall efficiency of MPM treatments.

An Update on Emergent Nano-Therapeutic Strategies against Pediatric Brain Tumors

Pediatric brain tumors are the major cause of pediatric cancer mortality. They comprise a diverse group of tumors with different developmental origins, genetic profiles, therapeutic options, and outcomes. Despite many technological advancements, the treatment of pediatric brain cancers has remained a challenge. Treatment options for pediatric brain cancers have been ineffective due to non-specificity, inability to cross the blood-brain barrier, and causing off-target side effects. In recent years, nanotechnological advancements in the medical field have proven to be effective in curing challenging cancers like brain tumors. Moreover, nanoparticles have emerged successfully, particularly in carrying larger payloads, as well as their stability, safety, and efficacy monitoring. In the present review, we will emphasize pediatric brain cancers, barriers to treating these cancers, and novel treatment options.

Study on combination therapy for lung cancer through pemetrexed-loaded mesoporous polydopamine nanoparticles

Lung cancer is one of the most commonly diagnosed cancers, and surgical resection is the optimal choice for the primary lung tumor. But for the secondary lung cancer, chemotherapy and combined radiotherapy still are the main strategies. To realize the combined treatment for non-small cell lung cancer (NSCLC), in this work, a nanoplatform based on pemetrexed (PE)-loaded mesoporous polydopamine (MPDA) nanoparticles were investigated. PE, a special therapeutic drug for NSCLC, was loaded into the MPDA nanoparticles via electrostatic attraction and was encapsulated with polyvinyl pyrrolidone (PVP). The results showed that, when irradiating with 808 nm near-infrared light, the PE loaded MPDA (MPDA@PE@PVP) nanoparticles have excellent photothermal conversion properties, which would result in increase of ambient temperature and could accelerate the release of PE. In vitro cell experiments proved that MPDA@PE@PVP nanoparticles have excellent killing ability for NSCLC A549 cells by the functions of PE and photothermal ability of MPDA nanoparticles. Meanwhile, the intra-cellular reactive oxygen species (ROS) levels of A549 cells in the MPDA@PE@PVP nanoparticle-treated group could be promoted significantly after irradiation, leading to the death of A549 cells. In vivo animal model results showed that MPDA@PE@PVP nanoparticles could gather at the tumor site by enhanced permeability and retention (EPR) effect and have significant inhibition ability for lung tumor by synergistic therapy of chemotherapy, photothermal therapy and photodynamic therapy.

Novel Insights Into Mesothelioma Therapy: Emerging Avenues and Future Prospects

Malignant mesothelioma is a rare and aggressive cancer that develops in the thin layer surrounding the mesothelium and is mainly caused by asbestos exposure. Despite improvements in patient prognosis with conventional cancer treatments, such as surgery, chemotherapy, and radiotherapy, there are still no curative treatment modalities for advanced disease. In recent years, new therapeutic avenues have been explored. Improved understanding of the mechanisms underlying the dynamic tumor interaction with the immune system has led to the development of immunotherapeutic approaches. Numerous recent clinical trials have shown a desire to develop more effective treatments that can be used to fight against the disease. Immune checkpoint inhibitors, oncolytic adenoviruses, and their combination represent a promising strategy that can be used to synergistically overcome immunosuppression in the mesothelioma tumor microenvironment. This review provides a synthesized overview of the current state of knowledge on new therapeutic options for mesothelioma with a focus on the results of clinical trials conducted in the field.

EGFR-targeted pemetrexed therapy of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare malignancy with poor prognosis, for which chemotherapy with pemetrexed (PEM) is among the few clinical treatments. PEM suffers, however, fast clearance, moderate drug exposure, and dose-limiting toxicities. Here, we report on epidermal growth factor receptor (EGFR)-targeted disulfide-crosslinked biodegradable chimaeric polymersomes (EGFR-CPs) to firmly load PEM and boost chemotherapy of MPM. EGFR-CPs encapsulating 8.7-16.4 wt.% PEM (EGFR-CPs-PEM) showed diameters of 62-65 nm and reduction-responsive drug release property. EGFR-CPs-PEM was more efficiently taken up by EGFR-overexpressed MSTO-211H cells, inducing about 4.7-fold enhanced anticancer activity compared with non-targeted CPs-PEM control. Intriguingly, the in vivo experiments in MSTO-211H xenograft mouse model revealed that EGFR-CPs-PEM brought about superior tumor deposition and penetration to CPs-PEM, and significantly more potent tumor repression than CPs-PEM and free PEM. This polymersome-enabled EGFR-targeted delivery of PEM offers an appealing therapeutic strategy for MPM.

Local Therapies and Modulation of Tumor Surrounding Stroma in Malignant Pleural Mesothelioma: A Translational Approach

Malignant Pleural Mesothelioma (MPM) is a rare and aggressive neoplasm of the pleural mesothelium, mainly associated with asbestos exposure and still lacking effective therapies. Modern targeted biological strategies that have revolutionized the therapy of other solid tumors have not had success so far in the MPM. Combination immunotherapy might achieve better results over chemotherapy alone, but there is still a need for more effective therapeutic approaches. Based on the peculiar disease features of MPM, several strategies for local therapeutic delivery have been developed over the past years. The common rationale of these approaches is: (i) to reduce the risk of drug inactivation before reaching the target tumor cells; (ii) to increase the concentration of active drugs in the tumor micro-environment and their bioavailability; (iii) to reduce toxic effects on normal, non-transformed cells, because of much lower drug doses than those used for systemic chemotherapy. The complex interactions between drugs and the local immune-inflammatory micro-environment modulate the subsequent clinical response. In this perspective, the main interest is currently addressed to the development of local drug delivery platforms, both cell therapy and engineered nanotools. We here propose a review aimed at deep investigation of the biologic effects of the current local therapies for MPM, including cell therapies, and the mechanisms of interaction with the tumor micro-environment.

Overcoming barriers by local drug delivery with liposomes

Localized or topical administration of drugs may be considered as a potential approach for overcoming the problems caused by the various biological barriers encountered in drug delivery. The combination of using localized administration routes and delivering drugs in nanoparticulate formulations, such as liposomes, may have additional advantages. Such advantages include prolonged retention of high drug loads at the site of action and controlled release of the drug, ensuring prolonged therapeutic effect; decreased potential for side-effects and toxicity (due to the high topical concentrations of drugs); and increased protection of drugs from possible harsh environments at the site of action. The use of targeted liposomal formulations may further potentiate any acquired therapeutic advantages. In this review we present the most advanced cases of localized delivery of liposomal formulations of drugs, which have been investigated pre-clinically and clinically in the last ten years, together with the reported therapeutic advantages, in each case.

Evaluation of optimum conditions for decoquinate nanoliposomes and their anticoccidial efficacy against diclazuril-resistant Eimeria tenella infections in broilers

Decoquinate (DQ) is used for prophylaxis against coccidian infections within the digestive tract of chickens, but DQ is extremely insoluble in water. Hence, improving the water solubility of DQ is extremely important. First, decoquinate nanoliposomes (DQNLs) were prepared by the thin-film dispersion-ultrasonic method. The preparation conditions of DQNLs were optimized using the orthogonal test. The optimal preparation conditions of DQNLs were: a ratio of egg-yolk lecithin:drug (w/w) of 10:1, ratio of egg-yolk lecithin:cholesterol (w/w) of 5:1, rotary-evaporation temperature of 50 ℃, and ultrasound duration of 15 min. The encapsulation efficiency of DQNLs prepared under these conditions reached 99.24 % and drug loading was 5.67 %. The characterization of optimized DQNLs was also done. Transmission electron microscopy of DQNLs showed that they had the characteristic structure of liposomes. The mean particle size was 115.6 nm. The polydispersity index was 0.175. The zeta potential was -39.1 mV. The stability of DQNLs was high upon storage at 4 ℃. In vivo studies demonstrated that the lower dose (5 mg/L) of DQNLs in drinking water obtained the similar anticoccidial efficacy to that of 40 mg/kg DQ in feed against diclazuril-resistance Eimeria tenella isolate. The in vitro inhibitory effect of DQNLs on the sporulation of Eimeria tenella oocysts was dose-dependent. Therefore, the anticoccidial efficacy of DQ was enhanced significantly after being encapsulated into nanoliposomes.

Preparation and Evaluation of Stearylamine-Bearing Pemetrexed Disodium-Loaded Cationic Liposomes In Vitro and In Vivo

Pemetrexed disodium (PMX) stands out in the treatment of non-small cell lung cancer (NSCLC), but with short half-life and toxic side effects. This study was to design cationic liposomes for targeting delivery PMX to the lungs. The PMX cationic liposome was prepared by thin-film hydration using stearylamine (SA) as the positive component of charge-regulating charge. Then, the PMX cationic liposome (SA-PMX-Lips) was characterized by particle size, morphology, entrapment efficiency (EE), and drug loading (DL). Finally, the drug release behavior in vitro, the pharmacokinetic study, and tissue distribution of SA-PMX-Lips were evaluated separately, with PMX solution (PMX-Sol) and PMX liposome (PMX-Lips) as the control. According to results, SA-PMX-Lips were spherical and the particle size was 219.7 ± 4.97 nm with a narrow polydispersity index (PDI) (0.231 ± 0.024) and a positive zeta potential 22.2 ± 0.52 mV. Its EE was 92.39 ± 1.94% and DL was 9.15 ± 0.07%. The results of in vitro and in vivo experiments showed that SA-PMX-Lips released slowly, prolonged retention time and increased the value of AUC. More notably, SA-PMX-Lips could improve the accumulation of drugs in the lungs and the relative uptake rate (Re) was 2.35 in the lungs, which indicated its lung targeting. In summary, SA-PMX-Lips showed the potential for the effective delivery of PMX and the treatment of NSCLC.

Metformin-loaded chitosomes for treatment of malignant pleural mesothelioma - A rare thoracic cancer

The purpose of this study was to design and evaluate chitosan dispersed lipid vesicles (chitosomes) as potential delivery carriers for repurposing metformin (Met) against malignant pleural mesothelioma. Chitosomes were prepared by directly hydrating the thin lipid film using chitosan solution as hydration medium, instead of using it as a coating agent. Developed chitosomes demonstrated spherical morphology, positive surface charge (~30 mV) and ~60% encapsulation efficiency. The calorimetric studies and X-ray diffraction pattern of Met-loaded chitosomes confirmed the successful encapsulation of Met inside the chitosome vesicles. Optimized chitosome formulation showed ~70% drug release in 72 h, displaying prolonged and controlled release of drug. Results demonstrated that Met encapsulated chitosomes possessed enhanced cellular internalization and improved cytotoxic potential. Our findings also supported inhibitory activity of chitosomes against metastatic property of pleural mesothelioma cells. The in-vitro tumor simulation studies further established anti-tumor activity of Met encapsulated chitosomes as supported by reduction in tumor volume and presence of minimal viable cells in tumor mass. The obtained results establish the effectiveness of chitosomes as delivery carrier for Met as treatment alternative for malignant pleural mesothelioma.

A Unique Gene-Silencing Approach, Using an Intelligent RNA Expression Device (iRed), Results in Minimal Immune Stimulation When Given by Local Intrapleural Injection in Malignant Pleural Mesothelioma

Background: We have recently introduced an intelligent RNA expression device (iRed), comprising the minimum essential components needed to transcribe short hairpin RNA (shRNA) in cells. Use of iRed efficiently produced shRNA molecules after transfection into cells and alleviated the innate immune stimulation following intravenous injection. Methods: To study the usefulness of iRed for local injection, the engineered iRed encoding luciferase shRNA (Luc iRed), complexed with cationic liposomes (Luc iRed/liposome-complexes), was intrapleurally injected into an orthotopic mesothelioma mouse model. Results: Luc iRed/liposome-complexes markedly suppressed the expression of a luciferase marker gene in pleurally disseminated mesothelioma cells. The suppressive efficiency was correlated with the expression level of shRNA within the mesothelioma cells. In addition, intrapleural injection of iRed/liposome-complexes did not induce IL-6 production in the pleural space and consequently in the blood compartment, although plasmid DNA (pDNA) or dsDNA (the natural construct for iRed) in the formulation did. Conclusion: Local delivery of iRed could augment the in vivo gene silencing effect without eliciting pronounced innate immune stimulation. Our results might hold promise for widespread utilization of iRed as an RNAi-based therapeutic for intracelial malignant cancers.

The Biology of Malignant Mesothelioma and the Relevance of Preclinical Models

Malignant mesothelioma (MM), especially its more frequent form, malignant pleural mesothelioma (MPM), is a devastating thoracic cancer with limited therapeutic options. Recently, clinical trials that used immunotherapy strategies have yielded promising results, but the benefits are restricted to a limited number of patients. To develop new therapeutic strategies and define predictors of treatment response to existing therapy, better knowledge of the cellular and molecular mechanisms of MM tumors and sound preclinical models are needed. This review aims to provide an overview of our present knowledge and issues on both subjects. MM shows a complex pattern of molecular changes, including genetic, chromosomic, and epigenetic alterations. MM is also a heterogeneous cancer. The recently described molecular classifications for MPM could better consider inter-tumor heterogeneity, while histo-molecular gradients are an interesting way to consider both intra- and inter-tumor heterogeneities. Classical preclinical models are based on use of MM cell lines in culture or implanted in rodents, i.e., xenografts in immunosuppressed mice or isografts in syngeneic rodents to assess the anti-tumor immune response. Recent developments are tumoroids, patient-derived xenografts (PDX), xenografts in humanized mice, and genetically modified mice (GEM) that carry mutations identified in human MM tumor cells. Multicellular tumor spheroids are an interesting in vitro model to reduce animal experimentation; they are more accessible than tumoroids. They could be relevant, especially if they are co-cultured with stromal and immune cells to partially reproduce the human microenvironment. Even if preclinical models have allowed for major advances, they show several limitations: (i) the anatomical and biological tumor microenvironments are incompletely reproduced; (ii) the intra-tumor heterogeneity and immunological contexts are not fully reconstructed; and (iii) the inter-tumor heterogeneity is insufficiently considered. Given that these limitations vary according to the models, preclinical models must be carefully selected depending on the objectives of the experiments. New approaches, such as organ-on-a-chip technologies or in silico biological systems, should be explored in MM research. More pertinent cell models, based on our knowledge on mesothelial carcinogenesis and considering MM heterogeneity, need to be developed. These endeavors are mandatory to implement efficient precision medicine for MM.

The Safety and Exploration of the Pharmacokinetics of Intrapleural Liposomal Curcumin

Background

Malignant pleural effusion (MPE) is the accumulation of fluid in the pleural cavity as a result of malignancies affecting the lung, pleura and mediastinal lymph nodes. Curcumin, a compound found in turmeric, has anti-cancer properties that could not only treat MPE accumulation but also reduce cancer burden. To our knowledge, direct administration of curcumin into the pleural cavity has never been reported, neither in animals nor in humans.

Purpose

To explore the compartmental distribution, targeted pharmacokinetics and the safety profile of liposomal curcumin following intrapleural and intravenous administration.

Methods

Liposomal curcumin (16 mg/kg) was administered into Fischer 344 rats by either intrapleural injection or intravenous infusion. The concentration of curcumin in plasma and tissues (lung, liver and diaphragm) were measured using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Blood and tissues were examined for pathological changes.

Results

No pleural or lung pathologies were observed following intrapleural liposomal curcumin administration. Total curcumin concentration peaked 1.5 hrs after the administration of intrapleural liposomal curcumin and red blood cell morphology appeared normal. A red blood cells abnormality (echinocytosis) was observed immediately and at 1.5 hrs after intravenous infusion of liposomal curcumin.

Conclusion

These results indicate that liposomal curcumin is safe when administered directly into the pleural cavity and may represent a viable alternative to intravenous infusion in patients with pleural-based tumors.

Diselenide-Pemetrexed Assemblies for Combined Cancer Immuno-, Radio-, and Chemotherapies

Immunotherapy has emerged as a promising new approach for cancer treatment. However, clinically available drugs have been limited until recently, and the antitumor efficacy of most cancer immunotherapies still needs to be improved. Herein, we develop diselenide-pemetrexed assemblies that combine natural killer (NK) cell-based cancer immunotherapy with radiotherapy and chemotherapy in a single system. The assemblies are prepared by co-assembly between pemetrexed and cytosine-containing diselenide through hydrogen bonds. Under γ-radiation, the hydrogen bonds are cleaved, resulting in the release of pemetrexed. At the same time, diselenide can be oxidized to seleninic acid, which suppresses the expression of human leukocyte antigen E (HLA-E) in cancer cells, thus activating the immune response of NK cells. In this way, cancer immunotherapy is combined with radiotherapy and chemotherapy, providing a new strategy for cancer treatment.

Rhodotorula glutinis as a living cell liposome to deliver polypeptide drugs in vivo

The potential advantages of recombinant microbes as oral drug carriers for curing diseases have attracted much attention. The use of recombinant oil microbes as living cell liposomes to carry polypeptide drugs may be an ideal polypeptide oral drug delivery system. GM4-ΔTS was constructed by LFH-PCR from Rhodotorula glutinis GM4, which was screened and preserved in our laboratory, and then transferred into choline-phosphate cytidylyltransferase (CCT), which is a rate-limiting enzyme for lecithin synthesis. The results showed that the CCT gene was highly expressed in the GM4-ΔTS strain and could significantly increase fatty acid and lecithin contents in GM4-ΔTS-PGK1-CCT. Moreover, insulin, H22-LP, and α-MSH were successfully introduced into cells in vitro, and the strain no longer proliferated in vivo, for safe and controllable polypeptide drug delivery. In vivo, normal mice were intragastrically administered with recombinant strains carrying insulin and α-MSH, and different levels of polypeptide drugs were detected in serum and tissue, respectively. Then, recombinant strains carrying insulin were administered to type II diabetes mellitus mice. The results showed that the strains could effectively reduce blood glucose levels in mice, which indicated that the recombinant strains could carry insulin into the body, and the drug effect was remarkable. Therefore, recombinant GM4-ΔTS-PGK1-CCT strains were successfully used as living cell liposomes to carry insulin, H22-LP, and α-MSH peptides into the body for the first time; additionally, these strains have enhanced safety, controllability, and efficacy.

Synergistic Enhancement of Cellular Uptake With CD44-Expressing Malignant Pleural Mesothelioma by Combining Cationic Liposome and Hyaluronic Acid-Lipid Conjugate

Malignant pleural mesothelioma (MPM) is a highly aggressive form of cancer, with a median survival of less than 1 year. It is well known that the hyaluronan (HA) receptor CD44 is highly expressed by MPM cells and is reported to be correlated with a poor prognosis. We herein report on the development of a new type if drug delivery system against CD44 that involves the use of lipid nanoparticles (LNPs) equipped with a new type of HA derivative. In this study, we evaluated HA-lipid conjugation (HAL) via the end of the HA molecule through reductive amination, a process that allowed the carboxylate group to remain intact. As a result, the HAL-modified LNP appears to be a potent nanoparticle for dealing with MPM. Surprisingly, the use of a combination of a cationic lipid and HAL had a synergistic effect on cellular uptake in MPM and consequently permitted an anti-cancer drug such as cis-diamminedichloro-platinum(II) (CDDP). Intrapleural injection of CDDP-loaded HAL-LNP (1.5 mg/kg as CDDP) per week significantly suppressed the progression of this type of cancer in an MPM orthotopic model. These results suggest that HAL-modified LNP represents a potent delivery system for MPM cells that express high levels of CD44.

Prolonged retention of liposomes in the pleural cavity of normal mice and high tumor distribution in mice with malignant pleural effusion, after intrapleural injection

Background: Intrapleural administration of compounds is a lung targeted, innovative therapeutic strategy for mesothelioma, which can be refined as a route for drug delivery that minimizes the potential for systemic toxicity. However, little is currently known about the retention of liposomal drugs at the site, after such topical administration. Purpose: To evaluate the retention of liposomes in lungs following intrapleural injection, and how this might be modulated by liposome properties and disease progression. Methods: DiR-incorporating liposomes with various lipid compositions and sizes were prepared, characterized (for size distribution and zeta potential) and injected intrapleurally in normal mice and mice with malignant pleural effusion (MPE). DiR retention in pleural cavity was followed by biofluorescence imaging. Results: Experimental results demonstrate that liposome size and PEG-coating, have a significant effect on residence time in the pleural cavity; negative surface charge does not. More than 20% liposomal-DiR is retained 24 d post-injection (in some cases), indicating the high potential towards localized diseases. Ex-vivo liposomal-DiR signal in tumors of MPE mice was similar to signal in liver, suggesting high tumor targeting potential of intrapleurally injected liposomes. Finally, no difference was noticed in liposomal-DiR retention between tumor-inoculated (MPE) and healthy mice, indicating the stability of liposomes in the presence of effusion (in MPE mice). Conclusion: The current study provides novel insights for using liposomes by intrapleural administration for the treatment of lung diseases.

Pemetrexed-loaded nanoparticles targeted to malignant pleural mesothelioma cells: an in vitro study

PURPOSE

Malignant pleural mesothelioma (MPM) is an aggressive tumor characterized by poor prognosis. Its incidence is steadily increasing due to widespread asbestos exposure. There is still no effective therapy for MPM. Pemetrexed (Pe) is one of the few chemotherapeutic agents approved for advanced-stage disease, although the objective response to the drug is limited. The use of gold nanoparticles (GNPs) as a drug delivery system promises several advantages, including specific targeting of malignant cells, with increased intracellular drug accumulation and reduced systemic toxicity, and, in the case of MPM, direct treatment administration into the pleural space. This study aims at exploring CD146 as a potential MPM cell-specific target for engineered Pe-loaded GNPs and to assess their effectiveness in inhibiting MPM cell line growth.

METHODS

MPM cell lines and primary cultures obtained by pleural effusions from MPM patients were assayed for CD146 expression by flow cytometry. Internalization by MPM cell lines of fluorescent dye-marked GNPs decorated with a monoclonal anti CD146 coated GNPs (GNP-HC) was proven by confocal microscopy. The effects of anti CD146 coated GNPs loaded with Pe (GNP-HCPe) on MPM cell lines were evaluated by cell cycle (flow cytometry), viability (MTT test), clonogenic capacity (soft agar assay), ROS production (electric paramagnetic resonance), motility (wound healing assay), and apoptosis (flow cytometry).

RESULTS

GNP-HC were selectively uptaken by MPM cells within 1 hour. MPM cell lines were blocked in the S cell cycle phase in the presence of GNP-HCPe. Both cell viability and motility were significantly affected by nanoparticle treatment compared to Pe. Apoptotic rate and ROS production were significantly higher in the presence of nanoparticles. Clonogenic capacity was completely inhibited following nanoparticle internalization.

CONCLUSION

GNP-HCPe treatment displays in vitro antineoplastic action and is more effective than Pe alone in inhibiting MPM cell line malignant phenotype. The innovative use of specifically targeted GNPs opens the perspective of local intrapleural administration to avoid normal cell toxicity and enhance chemotherapy efficacy.

PEGylated liposomes: immunological responses

A commonly held view is that nanocarriers conjugated to polyethylene glycol (PEG) are non-immunogenic. However, many studies have reported that unexpected immune responses have occurred against PEG-conjugated nanocarriers. One unanticipated response is the rapid clearance of PEGylated nanocarriers upon repeat administration, called the accelerated blood clearance (ABC) phenomenon. ABC involves the production of antibodies toward nanocarrier components, including PEG, which reduces the safety and effectiveness of encapsulated therapeutic agents. Another immune response is the hypersensitivity or infusion reaction referred to as complement (C) activation-related pseudoallergy (CARPA). Such immunogenicity and adverse reactivities of PEGylated nanocarriers may be of potential concern for the clinical use of PEGylated therapeutics. Accordingly, screening of the immunogenicity and CARPA reactogenicity of nanocarrier-based therapeutics should be a prerequisite before they can proceed into clinical studies. This review presents PEGylated liposomes, immunogenicity of PEG, the ABC phenomenon, C activation and lipid-induced CARPA from a toxicological point of view, and also addresses the factors that influence these adverse interactions with the immune system.

Development of dual-drug-loaded stealth nanocarriers for targeted and synergistic anti-lung cancer efficacy

Combination chemotherapy is widely exploited for suppressing drug resistance and achieving synergistic anticancer efficacy in the clinic. In this paper, the nanostructured targeting methotrexate (MTX) plus pemetrexed (PMX) chitosan nanoparticles (CNPs) were developed by modifying methoxy polye (thylene glycol) (mPEG), in which PEGylation CNPs was used as stealth nanocarriers (PCNPs) and MTX was employed as a targeting ligand and chemotherapeutic agent as well. Studies were undertaken on human lung adenocarcinoma epithelial (A549) and Lewis lung carcinoma (LLC) cell lines, revealing the anti-tumor efficacy of nanoparticle drug delivery system. The co-delivery nanoparticles (MTX-PMX-PCNPs) had well-dispersed with sustained release behavior. Cell counting kit-8 (CCK8) has been used to measure A549 cell viability and the research showed that MTX-PMX-PCNPs were much more effective than free drugs when it came to the inhibition of growth and proliferation. Cell cycle assay by flow cytometry manifested that the MTX-PMX-PCNPs exhibited stronger intracellular taken up ability than free drugs at the same concentration. In vivo anticancer effect results indicated that MTX-PMX-PCNPs exhibited a significantly prolong blood circulation, more tumoral location accumulation, and resulted in a robust synergistic anticancer efficacy in lung cancer in mice. The results clearly demonstrated that such unique synergistic anticancer efficacy of co-delivery of MTX and PMX via stealth nanocarriers, providing a prospective strategy for lung cancer treatment.

Liposomal Delivery Systems: Design Optimization and Current Applications

The liposome, a closed phospholipid bilayered vesicular system, has received considerable attention as a pharmaceutical carrier of great potential over the past 30 years. The ability of liposomes to encapsulate both hydrophilic and hydrophobic drugs, coupled with their biocompatibility and biodegradability, make liposomes attractive vehicles in the field of drug delivery. In addition, great technical advances such as remote drug loading, triggered release liposomes, ligand-targeted liposomes, liposomes containing combinations of drugs, and so on, have led to the widespread use of liposomes in diverse areas as delivery vehicles for anti-cancer, bio-active molecules, diagnostics, and therapeutic agents. In this review, we summarize design optimization of liposomal systems and invaluable applications of liposomes as effective delivery systems.