Co-delivery of Pirarubicin and Paclitaxel by Human Serum Albumin Nanoparticles to Enhance Antitumor Effect and Reduce Systemic Toxicity in Breast Cancers

Organic Nanodelivery Systems as a New Platform in the Management of Breast Cancer: A Comprehensive Review from Preclinical to Clinical Studies

Breast cancer accounts for approximately 25% of cancer cases and 16.5% of cancer deaths in women, and the World Health Organization predicts that the number of new cases will increase by almost 70% over the next two decades, mainly due to an ageing population. Effective diagnostic and treatment strategies are, therefore, urgently required for improving cure rates among patients since current therapeutic modalities have many limitations and side effects. Nanomedicine is evolving as a promising approach for cancer management, including breast cancer, and various types of organic and inorganic nanomaterials have been investigated for their role in breast cancer diagnosis and treatment. Following an overview on breast cancer characteristics and pathogenesis and challenges of the current treatment strategies, the therapeutic potential of biocompatible organic-based nanoparticles such as liposomes and polymeric micelles that have been tested in breast cancer models are reviewed. The efficacies of different drug delivery and targeting strategies are documented, ranging from synthetic to cell-derived nanoformulations together with a summary of the interaction of nanoparticles with externally applied energy such as radiotherapy. The clinical translation of nanoformulations for breast cancer treatment is summarized including those undergoing clinical trials.

Co-delivery of paclitaxel and etoposide prodrug by human serum albumin and PLGA nanoparticles: synergistic cytotoxicity in brain tumour cells

The aims of this study were to develop co-delivery systems of paclitaxel (PTX) and etoposide prodrug (4'-O-benzyloxycarbonyl-etoposide, ETP-cbz) based on non-cross-linked human serum albumin (HSA) and poly(lactide-co-glycolide) nanoparticles and to evaluate the synergistic potential of these drugs in vitro. The nanoformulations were prepared by the high-pressure homogenisation technique and characterised using DLS, TEM, SEM, AFM, HPLC, CZE, in-vitro release, and cytotoxicity in human and murine glioma cells. All nanoparticles had 90-150 nm in size and negative ζ-potentials. The Neuro2A cells were the most sensitive to both HSA- and PLGA-based co-delivery systems (IC₅₀ 0.024 µM and 0.053 µM, respectively). The drugs' synergistic effect (combination index < 0.9) was observed in the GL261 cells for both types of co-delivery formulations and in the Neuro2A cells for the HSA-based system. These nanodelivery systems may be useful to improve combination chemotherapy for brain tumour treatment. To our knowledge, this is the first report describing the non-cross-linked HSA-based co-delivery nanosuspension which was prepared using nab™ technology.

Nanotechnology as a tool to overcome macromolecules delivery issues

Nanocarriers can deliver drugs to specific organs or cells, potentially bridging the gap between a drug's function and its interaction with biological systems such as human physiology. The untapped potential of nanotechnology stems from its ability to manipulate materials, allowing control over physical and chemical properties and overcoming drug-related problems, e.g., poor solubility or poor bioavailability. For example, most protein drugs are administered parenterally, each with challenges and peculiarities. Some problems faced by bioengineered macromolecule drugs leading to poor bioavailability are short biological half-life, large size and high molecular weight, low permeability through biological membranes, and structural instability. Nanotechnology emerges as a promising strategy to overcome these problems. Nevertheless, the delivery system should be carefully chosen considering loading efficiency, physicochemical properties, production conditions, toxicity, and regulations. Moving from the bench to the bedside is still one of the major bottlenecks in nanomedicine, and toxicological issues are the greatest challenges to overcome. This review provides an overview of biotech drug delivery approaches, associated nanotechnology novelty, toxicological issues, and regulations.

Molecular Imaging of Oxygenation Changes during Immunotherapy in Combination with Paclitaxel in Triple Negative Breast Cancer

Hypoxia is a common feature of the tumor microenvironment, including that of triple-negative breast cancer (TNBC), an aggressive breast cancer subtype with a high five-year mortality rate. Using [18F]-fluoromisonidazole (FMISO) positron emission tomography (PET) imaging, we aimed to monitor changes in response to immunotherapy (IMT) with chemotherapy in TNBC. TNBC-tumor-bearing mice received paclitaxel (PTX) ± immune checkpoint inhibitors anti-programmed death 1 and anti-cytotoxic T-lymphocyte 4. FMISO-PET imaging was performed on treatment days 0, 6, and 12. Max and mean standard uptake values (SUVmax and SUVmean, respectively), histological analyses, and flow cytometry results were compared. FMISO-PET imaging revealed differences in tumor biology between treatment groups prior to tumor volume changes. 4T1 responders showed SUVmean 1.6-fold lower (p = 0.02) and 1.8-fold lower (p = 0.02) than non-responders on days 6 and 12, respectively. E0771 responders showed SUVmean 3.6-fold lower (p = 0.001) and 2.7-fold lower (p = 0.03) than non-responders on days 6 and 12, respectively. Immunohistochemical analyses revealed IMT plus PTX decreased hypoxia and proliferation and increased vascularity compared to control. Combination IMT/PTX recovered the loss of CD4+ T-cells observed with single-agent therapies. PET imaging can provide timely, longitudinal data on the TNBC tumor microenvironment, specifically intratumoral hypoxia, predicting therapeutic response to IMT plus chemotherapy.

Improvement of the bladder perfusion curative effect through tight junction protein degradation induced by magnetic temperature-sensitive hydrogels

Postoperative intravesical instillation of chemotherapy is a routine procedure for non-muscular invasive bladder cancer (NMIBC). However, traditional bladder perfusion methods have insufficient exposure time, resulting in unsatisfactory therapeutic effects. In the present study, a chitosan (CS)-based in situ forming depot (ISFD) delivery system, including Fe₃O₄ magnetic nanoparticles (Fe₃O₄-MNP), CS, and β-glycerophosphate (GP) as main components, was synthesized. Pirarubicin (THP), as a chemotherapeutic drug, was loaded into the new system. Results showed that our carrier system (Fe₃O₄-THP-CS/GP) was converted into gel and attached to the bladder wall, possessing loose network structures with magnetic targeting and sustained release properties. Moreover, its retention time in bladder was more than 72 h accompanied by a suitable expansion rate and good degradation characteristics. The antitumor activities of Fe₃O₄-THP-CS/GP were more effective both in vitro and in vivo than the free THP solution. In the study of its mechanism, results showed that Fe₃O₄-THP-CS/GP suppressed the expression of occludin (OCLN) and affected tight junctions (TJ) between urothelial cells to promote THP absorption.

Laser-responsive multi-functional nanoparticles for efficient combinational chemo-photodynamic therapy against breast cancer

Herein, novel laser-responsive multi-functional nanoparticles (NPs-Lip@PTX/CyA/Ce6) were fabricated with bovine serum albumins (BSA) based nanoparticles, which simultaneously carried chemotherapeutic drug paclitaxel (PTX) and P-gp inhibitor cyclosporin A (CyA), as core and photosensitizer agent Chlorin e6 (Ce6) loaded Tf-modified liposomal bilayer as shell. NPs-Lip@PTX/CyA/Ce6 exhibited apparent core-shell structure morphology with particle size of 160.9 ± 1.7 nm and zeta potential of - 26.7 ± 0.6 mV, indicating their excellent stability in aqueous solution. Besides, NPs-Lip@PTX/CyA/Ce6 possessed laser-responsive release profiles upon laser irradiation at specific wavelength, which was favor to exert efficient combinatorial chemo-photodynamic therapy and effectively reverse the multiple drug resistance (MDR). Under laser irradiation, as expected, NPs-Lip@PTX/CyA/Ce6 demonstrated superb intracellular ROS productivity and fantastic in vitro and in vivo anti-cancer therapy effect but absent of systemic toxicity. In conclusion, the nano-drug delivery system would be prospectively applied in clinic as resultful therapeutic tactic for investing compositional chemo-photodynamic therapy synergistically.

Targeted delivery of albumin nanoparticles for breast cancer: A review

Breast cancer has been identified as one of the most common cancers diagnosed in women. Various nanotechnology platforms offering unique features are considered in breast cancer treatment. Albumin is a versatile biodegradable, biocompatible, non-toxic and non-immunogenic protein nanocarrier. These characteristics attracted strong attention to fabricate albumin nanoparticles to deliver chemotherapeutic agents without major adverse effects. Albumin nanoparticles can undergo surface modifications using different ligands promoting tumor-targeted drug delivery. Moreover, multifunctional albumin nanoparticle is an upcoming strategy to attain efficient cancer therapy. This review gives an account of the potential albumin nanoparticles developed for chemotherapeutic drug delivery and its targeted approach for breast cancer. It also covers different multifunctional therapies available using albumin nanoparticles as breast cancer theranostics.

Emerging Albumin-Binding Anticancer Drugs for Tumor-Targeted Drug Delivery: Current Understandings and Clinical Translation

Albumin has shown remarkable promise as a natural drug carrier by improving pharmacokinetic (PK) profiles of anticancer drugs for tumor-targeted delivery. The exogenous or endogenous albumin enhances the circulatory half-lives of anticancer drugs and passively target the tumors by the enhanced permeability and retention (EPR) effect. Thus, the albumin-based drug delivery leads to a potent antitumor efficacy in various preclinical models, and several candidates have been evaluated clinically. The most successful example is Abraxane, an exogenous human serum albumin (HSA)-bound paclitaxel formulation approved by the FDA and used to treat locally advanced or metastatic tumors. However, additional clinical translation of exogenous albumin formulations has not been approved to date because of their unexpectedly low delivery efficiency, which can increase the risk of systemic toxicity. To overcome these limitations, several prodrugs binding endogenous albumin covalently have been investigated owing to distinct advantages for a safe and more effective drug delivery. In this review, we give account of the different albumin-based drug delivery systems, from laboratory investigations to clinical applications, and their potential challenges, and the outlook for clinical translation is discussed. In addition, recent advances and progress of albumin-binding drugs to move more closely to the clinical settings are outlined.

Regulation of drug release performance using mixed doxorubicin-doxorubicin dimer nanoparticles as a pH-triggered drug self-delivery system

A mixed drug self-delivery system (DSDS) with high drug content (>50%) was developed to regulate pH-triggered drug release, based on two doxorubicin (DOX)-DOX dimmers: D-DOXADH and D-DOXcar conjugated with acid-labile dynamic covalent bonds (hydrazone and carbamate, respectively) and stabilized with PEGylated D-DOXADH (D-DOXADH-PEG). Owing to the different stability of the dynamic covalent bonds in the two dimers and the noncovalent interaction between them, pH-triggered drug release could be easily regulated by adjusting the feeding ratios of the two DOX-DOX dimers in the mixed DSDS. Similar in vitro cellular toxicity was achieved with the mixed DSDS nanoparticles prepared with different feeding ratios. The mixed DSDS nanoparticles had a similar DOX content and diameter but different drug releasing rates. The MTT assays revealed that a high anti-tumor efficacy could be achieved with the slow-release mixed DSDS nanoparticles.

Recent Advances in the Treatment of Bone Metastases and Primary Bone Tumors: An Up-to-Date Review

In the last decades, the treatment of primary and secondary bone tumors has faced a slow-down in its development, being mainly based on chemotherapy, radiotherapy, and surgical interventions. However, these conventional therapeutic strategies present a series of disadvantages (e.g., multidrug resistance, tumor recurrence, severe side effects, formation of large bone defects), which limit their application and efficacy. In recent years, these procedures were combined with several adjuvant therapies, with different degrees of success. To overcome the drawbacks of current therapies and improve treatment outcomes, other strategies started being investigated, like carrier-mediated drug delivery, bone substitutes for repairing bone defects, and multifunctional scaffolds with bone tissue regeneration and antitumor properties. Thus, this paper aims to present the types of bone tumors and their current treatment approaches, further focusing on the recent advances in new therapeutic alternatives.

TMTP1-Modified, Tumor Microenvironment Responsive Nanoparticles Co-Deliver Cisplatin and Paclitaxel Prodrugs for Effective Cervical Cancer Therapy

Background and Purpose

Cisplatin-paclitaxel (TP) combination chemotherapy as the first-line therapy for numerous cancers is hindered by its inadequate accumulation in tumors and severe side effects resulting from non-specific distribution. The aim of this study is to explore whether TMTP1-modified, cisplatin and paclitaxel prodrugs co-loaded nanodrug could improve cervical cancer chemotherapy and relieve its side effects through active and passive tumor targeting accumulation and controlled drug release.

Methods

TDNP, with capacities of active targeting for tumors and controlled drug release, was prepared to co-deliver cisplatin and paclitaxel prodrugs. The characteristics were investigated, including the diameter, surface zeta potential, stability and tumor microenvironment (TME) dependent drug release profiles. Cellular uptake, cytotoxicity, drug accumulation in tumors, antitumor effects and safety analysis were evaluated in vitro and in vivo.

Results

The oxidized cisplatin and the paclitaxel linked to the polymer achieved a high loading effciency of over 80% and TME-dependent sustained drug release. Moreover, TMTP1 modification enhanced cellular uptake of TDNP and further improved the cytotoxicity of TDNP in vitro. In vivo, TDNP showed an extended blood circulation and increased accumulation in SiHa xenograft models with the aid of TMTP1. More importantly, TDNP controlled tumor growth without life-threatening side effects.

Conclusion

Our study provided a novel TP co-delivery platform for targeted chemotherapy of cervical cancer, which was promising to improve the therapeutic effcacy of TP and may also have application in other tumors.

Biomimetic nanotherapy: core-shell structured nanocomplexes based on the neutrophil membrane for targeted therapy of lymphoma

Background

Non-Hodgkin’s lymphoma (NHL) is a malignant disease of lymphoid tissue. At present, chemotherapy is still the main method for the treatment of NHL. R-CHOP can significantly improve the survival rate of patients. Unfortunately, DOX is the main cytotoxic drug in R-CHOP and it can lead to adverse reactions. Therefore, it is particularly important to uncover new treatment options for NHL.

Results

In this study, a novel anti-tumor nanoparticle complex Nm@MSNs-DOX/SM was designed and constructed in this study. Mesoporous silica nanoparticles (MSNs) loaded with Doxorubicin (DOX) and anti-inflammatory drugs Shanzhiside methylester (SM) were used as the core of nanoparticles. Neutrophil membrane (Nm) can be coated with multiple nanonuclei as a shell. DOX combined with SM can enhance the anti-tumor effect, and induce apoptosis of lymphoma cells and inhibit the expression of inflammatory factors related to tumorigenesis depending on the regulation of Bcl-2 family-mediated mitochondrial pathways, such as TNF-α and IL-1β. Consequently, the tumor microenvironment (TME) was reshaped, and the anti-tumor effect of DOX was amplified. Besides, Nm has good biocompatibility and can enhance the EPR effect of Nm@MSNs-DOX/SM and increase the effect of active targeting tumors.

Conclusions

This suggests that the Nm-modified drug delivery system Nm@MSNs-DOX/SM is a promising targeted chemotherapy and anti-inflammatory therapy nanocomplex, and may be employed as a specific and efficient anti-Lymphoma therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00922-4.

Preparation and characterization of paclitaxel palmitate albumin nanoparticles with high loading efficacy: an in vitro and in vivo anti-tumor study in mouse models

BACKGROUND

Combination of the prodrug technique with an albumin nano drug-loaded system is a novel promising approach for cancer treatment. However, the long-lasting and far-reaching challenge for the treatment of cancers lies in how to construct the albumin nanometer drug delivery system with lead compounds and their derivatives.

METHODS

In this study, we reported the preparation of injectable albumin nanoparticles (NPs) with a high and quantitative drug loading system based on the Nab^TM technology of paclitaxel palmitate (PTX-PA).

RESULTS

Our experimental study on drug tissue distribution in vivo demonstrated that the paclitaxel palmitate albumin nanoparticles (Nab-PTX-PA) remained in the tumor for a longer time post-injection. Compared with saline and paclitaxel albumin nanoparticles (Abraxane^®), intravenous injection of Nab-PTX-PA not only reduced the toxicity of the drug in normal organs, and increased the body weight of the animals but maintained sustained release of paclitaxel (PTX) in the tumor, thereby displaying an excellent antitumor activity. Blood routine analysis showed that Nab-PTX-PA had fewer adverse effects or less toxicity to the normal organs, and it inhibited tumor cell proliferation more effectively as compared with commercial paclitaxel albumin nanoparticles.

CONCLUSIONS

This carrier strategy for small molecule drugs is based on naturally evolved interactions between long-chain fatty acids (LCFAs) and Human Serum Albumin (HSA), demonstrated here for PTX. Nab-PTX-PA shows higher antitumor efficacy in vivo in breast cancer models. On the whole, this novel injectable Nab-PTX-PA has great potential as an effective drug delivery system in the treatment of breast cancer.

Effect of Paclitaxel/etoposide co-loaded polymeric nanoparticles on tumor size and survival rate in a rat model of glioblastoma

The aim of this work is to co-load paclitaxel (PTX) and etoposide (ETP) in methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid) nanoparticles (mPEG-PLGA NPs) to overcome pharmacokinetics and physiological limitations and enhance therapeutic efficacy for treating intracranial glioblastoma. Both drugs were loaded into mPEG-PLGA NPs by a nano-precipitation method. The resultant NPs demonstrated an enhanced cytotoxic effect indicated by lower IC₅₀ values and augmented cell apoptosis to U87 and C6 glioma cell lines compared to both free drugs. Additionally, blood compatibility assays showed that the PTX/ETP co-loaded mPEG-PLGA NPs did not induce blood hemolysis, blood clotting, or platelet aggregation. In vivo anti-glioma efficacy evaluation in rats bearingintracranialC6glioma revealed a superior anti-glioma activity for the treatment with PTX/ETP co-loaded mPEG-PLGA NPs compared to other formulations, particularly a significantly longer median survival, 76 days compared to 36 days for free PTX and 37 days for free ETP treatment, respectively, and higher tumor regression, proved by magnetic resonance imaging (MRI).

PEGylated N-(2 hydroxypropyl) methacrylamide polymeric micelles as nanocarriers for the delivery of doxorubicin in breast cancer

In the present study, polymeric micelles constituted of N-(2-hydroxypropyl)methacrylamide (HPMA) and methoxypoly(ethylene glycol) (mPEG)-based copolymer, mPEG-b-HPMA was studied for the delivery of an anticancer drug, doxorubicin (DOX) by physically loading the drug into its core. A series of mPEG-b-HPMA copolymers of different molecular weights (MWs, ∼4000-25,000 Da) by using various initiator: monomer feed ratios (1:25/75/125/175) were synthesized by radical polymerization technique. The DOX-loaded micelles were prepared at different drug to polymer ratios by thin film hydration method. Block copolymers were structurally characterized by gel permeation chromatography (GPC), ¹H-NMR spectroscopy, fourier transform infrared spectroscopy (FTIR), and critical micelles concentration studies. The DLS and SEM studies indicated that the micelles were spherical with diameters ∼20-100 nm. The DOX-loaded mPEG-b-HPMA micelles, P6-M1, prepared by the polymer synthesized using initiator: monomer feed ratios of 1:175 and at polymer to drug ratios of 10:1 exhibited low particle sizes (∼46.8 nm), highest drug loading and encapsulation efficiencies (5.6 %, and 63.3 %, respectively) compared to the other tested formulations. Confocal microscopy study indicated that the P6-M1 was taken up by breast cancer cell lines, 4T1, MCF-7, and MDA-MB-231in a time-dependent manner. P6-M1 displayed lower half maximal inhibitory concentration (IC₅₀) compared to free drug in all tested treatment durations compared to free DOX. P6-M1 was safe in hemolysis studies with sustained DOX residence in circulation compared to free DOX. The results indicated that mPEG-b-HPMA could be utilized to load DOX effectively, and the optimized nano-micelles, P6-M1 could serve as a promising nanomedicine to treat breast cancer.

A novel preparative method for nanoparticle albumin-bound paclitaxel with high drug loading and its evaluation both in vitro and in vivo

We developed a novel preparative method for nanoparticle albumin-bound (nab) paclitaxel with high drug loading, which was based on improved paclitaxel solubility in polyethylene glycol (PEG) and self-assembly of paclitaxel in PEG with albumin powders into nanoparticles. That is, paclitaxel and PEG were firstly dissolved in ethanol, which was subsequently evaporated under vacuum. The obtained liquid was then mixed with human serum albumin powders. Thereafter, the mixtures were added into phosphate-buffered saline and nab paclitaxel suspensions emerged after ultrasound. Nab paclitaxel was finally acquired after dialysis and freeze drying. The drug loading of about 15% (W/V) were realized in self-made nab paclitaxel, which was increased by approximately 50% compared to 10% (W/V) in Abraxane. Now this new preparative method has been authorized to obtain patent from China and Japan. The similar characteristics of self-made nab paclitaxel compared to Abraxane were observed in morphology, encapsulation efficiency, in vitro release, X-ray diffraction analysis, differential scanning calorimetry analysis, and circular dichroism spectra analysis. Consistent concentration-time curves in rats, biodistributions in mice, anti-tumor activities in mice, and histological transmutation in mice were also found between Abraxane and self-made nanoparticles. In a word, our novel preparative method for nab paclitaxel can significantly improve drug loading, obviously decrease product cost, and is considered to have potent practical value.

The Uniqueness of Albumin as a Carrier in Nanodrug Delivery

Albumin is an appealing carrier in nanomedicine because of its unique features. First, it is the most abundant protein in plasma, endowing high biocompatibility, biodegradability, nonimmunogenicity, and safety for its clinical application. Second, albumin chemical structure and conformation allows interaction with many different drugs, potentially protecting them from elimination and metabolism in vivo, thus improving their pharmacokinetic properties. Finally, albumin can interact with receptors overexpressed in many diseased tissues and cells, providing a unique feature for active targeting of the disease site without the addition of specific ligands to the nanocarrier. For this reason, albumin, characterized by an extended serum half-life of around 19 days, has the potential of promoting half-life extension and targeted delivery of drugs. Therefore, this article focuses on the importance of albumin as a nanodrug delivery carrier for hydrophobic drugs, taking advantage of the passive as well as active targeting potential of this nanocarrier. Particular attention is paid to the breakthrough NAB-Technology, with emphasis on the advantages of Nab-Paclitaxel (Abraxane), compared to the solvent-based formulations of Paclitaxel, i.e., CrEL-paclitaxel (Taxol) in a clinical setting. Finally, the role of albumin in carrying anticancer compounds is depicted, with a particular focus on the albumin-based formulations that are currently undergoing clinical trials. The article sheds light on the power of an endogenous substance, such as albumin, as a drug delivery system, signifies the importance of the drug vehicle in drug performance in the biological systems, and highlights the possible future trends in the use of this drug delivery system.

Lipoparticles for Synergistic Chemo-Photodynamic Therapy to Ovarian Carcinoma Cells: In vitro and in vivo Assessments

PURPOSE

Lipoparticles are the core-shell type lipid-polymer hybrid systems comprising polymeric nanoparticle core enveloped by single or multiple pegylated lipid layers (shell), thereby melding the biomimetic properties of long-circulating vesicles as well as the mechanical advantages of the nanoparticles. The present study was aimed at the development of such an integrated system, combining the photodynamic and chemotherapeutic approaches for the treatment of multidrug-resistant cancers.

METHODS

For this rationale, two different sized Pirarubicin (THP) loaded poly lactic-co-glycolic acid (PLGA) nanoparticles were prepared by emulsion solvent evaporation technique, whereas liposomes containing Temoporfin (mTHPC) were prepared by lipid film hydration method. Physicochemical and morphological characterizations were done using dynamic light scattering, laser doppler anemometry, atomic force microscopy, and transmission electron microscopy. The quantitative assessment of cell damage was determined using MTT and reactive oxygen species (ROS) assay. The biocompatibility of the nanoformulations was evaluated with serum stability testing, haemocompatibility as well as acute in vivo toxicity using female albino (BALB/c) mice.

RESULTS AND CONCLUSION

The mean hydrodynamic diameter of the formulations was found between 108.80 ± 2.10 to 405.70 ± 10.00 nm with the zeta (ζ) potential ranging from -12.70 ± 1.20 to 5.90 ± 1.10 mV. Based on the physicochemical evaluations, the selected THP nanoparticles were coated with mTHPC liposomes to produce lipid-coated nanoparticles (LCNPs). A significant (p< 0.001) cytotoxicity synergism was evident in LCNPs when irradiated at 652 nm, using an LED device. No incidence of genotoxicity was observed as seen with the comet assay. The LCNPs decreased the generalized in vivo toxicity as compared to the free drugs and was evident from the serum biochemical profile, visceral body index, liver function tests as well as renal function tests. The histopathological examinations of the vital organs revealed no significant evidence of toxicity suggesting the safety and efficacy of our lipid-polymer hybrid system.

Construction of homologous cancer cell membrane camouflage in a nano-drug delivery system for the treatment of lymphoma

BACKGROUND

Non-Hodgkin's lymphoma (NHL) possesses great heterogeneity in cytogenetics, immunophenotype and clinical features, and chemotherapy currently serves as the main treatment modality. Although employing monoclonal antibody targeted drugs has significantly improved its overall efficacy, various patients continue to suffer from drug resistance or recurrence. Chinese medicine has long been used in the treatment of malignant tumors. Therefore, we constructed a low pH value sensitivity drug delivery system based on the cancer cell membrane modified mesoporous silica nanoparticles loaded with traditional Chinese medicine, which can reduce systemic toxicity and improve the therapeutic effect for the targeted drug delivery of tumor cells.

RESULTS

Accordingly, this study put forward the construction of a nano-platform based on mesoporous silica nanoparticles (MSNs) loaded with the traditional Chinese medicine isoimperatorin (ISOIM), which was camouflaged by the cancer cell membrane (CCM) called CCM@MSNs-ISOIM. The proposed nano-platform has characteristics of immune escape, anti-phagocytosis, high drug loading rate, low pH value sensitivity, good biocompatibility and active targeting of the tumor site, blocking the lymphoma cell cycle and promoting mitochondrial-mediated apoptosis.

CONCLUSIONS

Furthermore, this study provides a theoretical basis in finding novel clinical treatments for lymphoma.

Amphiphilic block polymer-based self-assembly of high payload nanoparticles for efficient combinatorial chemo-photodynamic therapy

Combinatorial chemo-photodynamic therapy is regared as effective cancer therapy strategy, which could be realized via multiple nano-drug delivery system. Herein, novel high payload nanoparticles stabilized by amphiphilic block polymer cholesterol-b-poly(ethylene glycol) (PEG)₂₀₀₀ (Chol-PEG₂₀₀₀) were fabricated for loading chemotherapeutic drug 10-hydroxycamptothecin (HCPT) and photosensitizer chlorin e6 (Ce6). The obtained HCPT/Ce6 NPs showed uniform rod-like morphology with a hydration diameter of 178.9 ± 4.0 nm and excellent stability in aqueous solution. HCPT and Ce6 in the NPs displayed differential release profile, which was benefit for preferentially exerting the photodynamic effect and subsequently enhancing the sensitivity of the cells to HCPT. Under laser irradiation, the NPs demonstrated fantastic in vitro and in vivo anticancer efficiency due to combinational chemo-photodynamic therapy, enhanced cellular uptake effectiveness, and superb intracellular ROS productivity. Besides, the NPs were proved as absent of systemic toxicity. In summary, this nanoparticle delivery system could be hopefully utilized as effective cancer therapy strategy for synergistically exerting combined chemo-photodynamic therapy in clinic.

In vivo Serum Enabled Production of Ultrafine Nanotherapeutics for Cancer Treatment

Systemic delivery of hydrophobic anti-cancer drugs with nanocarriers, particularly for drug-resistant and metastatic cancer, remain a challenge because of the difficulty to achieve high drug loading, while maintaining a small hydrodynamic size and colloid stability in blood to ensure delivery of an efficacious amount of drug to tumor cells. Here we introduce a new approach to address this challenge. In this approach, nanofibers of larger size with good drug loading capacity are first constructed by a self-assembly process, and upon intravascular injection and interacting with serum proteins in vivo, these nanofibers break down into ultra-fine nanoparticles of smaller size that inherit the drug loading property from their parent nanofibers. We demonstrate the efficacy of this approach with a clinically available anti-cancer drug: paclitaxel (PTX). In vitro, the PTX-loaded nanoparticles enter cancer cells and induce cellular apoptosis. In vivo, they demonstrate prolonged circulation in blood, induce no systemic toxicity, and show high potency in inhibiting tumor growth and metastasis in both mouse models of aggressive, drug-resistant breast cancer and melanoma. This study points to a new strategy toward improved anti-cancer drug delivery and therapy.

Research advances in nanomedicine, immunotherapy, and combination therapy for leukemia

In the past decade, clinical and laboratory studies have led to important new insights into the biology of leukemia and its treatment. This review describes the progress of leukemia research in the United States in recent years. Whereas the traditional method of treatment is chemotherapy, it is nonselective and could induce systemic toxicities. Thus, in parallel with research on new chemotherapies, great emphasis has been placed on developing immunotherapies. Here, we will review the current immunotherapies available in research and development that overcome current challenges, specifically looking in the field of chimeric antigen receptor T-cell (CAR-T) therapies, checkpoint inhibitors, and antibody-drug conjugates. With about 100 clinical trials for CAR-T therapies and 30 in checkpoint inhibitors for leukemia treatment, scientists are trying to make these technologies cheaper, faster, and more feasible. Further describing the delivery of these therapeutics, we look at the current progress, clinical, and preclinical status of nano-based medicines such as liposomes, polymeric micelles, and metal nanoparticles. Taking advantage of their physicochemical and biologic properties, nanoparticles have been shown to increase the efficacy of commonly administered chemotherapies with reduced adverse effects.

Co-delivery system of chemotherapy drugs and active ingredients from natural plants: a brief overview of preclinical research for cancer treatment

Introduction: Many active ingredients from natural plants (AINPs) have been revealed to possess remarkable anticancer properties. Combination chemotherapy of chemo-drugs and AINPs has also proven to be more advantageous than individual chemo-drug treatment with respect to enhancing efficiency, alleviating toxicity, and controlling the development of multidrug resistance (MDR). Co-delivery is considered a promising method to effectively achieve and manage combination chemotherapy of chemo-drugs and AINPs, and various distinctive and functional co-delivery systems have been designed for these purposes to date.Areas covered: This review focuses on recent preclinical investigations of co-delivery systems for chemo-drugs and AINPs as new cancer treatment modalities. We particularly emphasize the apparent treatment advantages of these approaches, including augmenting efficiency, reducing toxicity, and controlling MDR.Expert opinion: There has already been notable progress in the application of combination chemotherapy with co-delivery systems loaded with chemo-drugs and AINPs based on results with cellular and animal models. The main challenge is to translate these successes into new anticancer compound preparations and promote their clinical application in practice. Nevertheless, continuous efforts with new designs of co-delivery systems remain essential, providing a foundation for future clinical research and development of new anticancer drugs.

Synthesis of Acid-Labile Poly(Doxazolidine) as a Polyprodrug with an Ultra-High Drug Content for Self-Delivery of High-Performance Chemotherapeutics

Drug self-delivery systems (DSDSs) have attracted intense attention due to their high drug content. However, their practical application still suffers from their premature drug leakage, slow drug release, and/or low antitumor efficacy of the released small molecular drugs. Here, acid-labile poly(Doxazolidine) (P(Doxaz)) is designed as a polyprodrug for the self-delivery of high antitumor chemotherapeutics (Doxazolidine (Doxaz)), with an ultrahigh Doxaz content of 92.45%. The P(Doxaz) nanoparticles could completely degrade into Doxaz within 10 h in the simulated tumor intracellular microenvironment, with a low drug leakage of 12.9% over 12 h in the normal physiological media. Owing to the ultrahigh drug content, fast acid-triggered degradation and drug release, and high antitumor efficacy of Doxaz, the proposed DSDS possesses an enhanced antiproliferation efficacy compared to the free DOX, demonstrating its potential in future tumor treatments.

Novel carrier-free nanoparticles composed of 7-ethyl-10-hydroxycamptothecin and chlorin e6: Self-assembly mechanism investigation and in vitro/in vivo evaluation

The combination therapy strategy based on both chemotherapy and photodynamic therapy (PDT) exhibits great potential for advanced cancer treatment. Multimodal nanodrug delivery systems based on both chemotherapeutic drug and photodynamic agent have been proven to possess excellent synergistic efficacy. In this study, 7-ethyl-10-hydroxycamptothecin (SN38) and chlorin e6 (Ce6) were co-assembled into novel carrier-free nanoparticles (SN38/Ce6 NPs) via simple antisolvent precipitation method. As expected, SN38/Ce6 NPs exhibited uniform morphology with a particle size of around 150 nm and a zeta potential of about -30 mV, good stability in aqueous solution/at lyophilized state and high cellular uptake efficiency against murine mammary carcinoma (4T1) cell lines. Besides, enhanced singlet oxygen generation capacity of the nanoparticles was both observed in test-tube and in 4T1 cell lines in contrast with Ce6 injection. Moreover, a ∼85 % inhibition rate of SN38/Ce6 NPs with laser was detected, which was significantly higher (P < 0.05) than those without laser (∼65 %) and injections (less than 20 %), verified the excellent synergistic antitumor efficacy of the nanoparticles due to combined chemo-photodynamic therapy, enhanced tumor accumulation and higher cellular internalization. Notably, chemical thermodynamic method and molecular dynamics (MD) simulations supplied solid data and visual images to estimate the driving forces for the self-assembly process of the carrier-free nanoparticles as primary hydrophobic interactions (π-π stacking) and subordinate hydrogen bonds. Conclusively, the above self-assembled carrier-free nanoparticles represented a promising synergistic anticancer strategy capable of maximal therapeutic efficacy and minimal systemic toxicity. Moreover, the application of thermodynamic method together with MD simulations in the investigation of NPs self-assembly process also provided new ideas for the assembly mechanism exploration of more complicated nanodrug delivery system.

Co-Delivery of Prednisolone and Curcumin in Human Serum Albumin Nanoparticles for Effective Treatment of Rheumatoid Arthritis

Background

Prednisolone (PD) is extremely effective for treating rheumatoid arthritis (RA). However, it distributes nonspecifically throughout the body and its use is associated with serious side effects, which promoted us to compound it into a phytomedicine for greater efficacy and safety.

Methods

We combined PD with curcumin (CU), an effective monomer from traditional Chinese medicine, and human serum albumin (HSA) in a nanoparticulate system (N-PD/CU) to compensate for the poor bioavailability of PD and CU. N-PD/CU was prepared by high-pressure homogenization, and its characteristics were evaluated in vitro. Next, we investigated its toxicity and mechanism of anti-inflammatory to macrophages. Finally, its pharmacokinetics, biodistribution and therapeutic efficacy were assessed in rats with adjuvant-induced arthritis (AIA).

Results

N-PD/CU showed a narrow size distribution around 150.4 ± 2.4 nm, a polydispersity index of 0.22 ± 0.02 and drug loading efficiency (DLE) of 88.75 ± 1.82% for PD and 85.79 ± 1.43% for CU. N-PD/CU showed sustained release of both drugs in vitro. N-PD/CU had no toxicity to macrophages in vitro on concentrations between 0.1 and 1.2 μmol/mL. In activated macrophages, N-PD decreased levels of pro-inflammatory cytokines, while N-CU increased levels of anti-inflammatory IL-10, and N-PD/CU exhibited best therapeutic effect in vitro, suggesting co-delivery of PD and CU may synergistically control the course of RA. In AIA rats, N-PD/CU accumulated in inflamed joints through the effect of extravasation through leaky vasculature and subsequent inflammatory cell-mediated sequestration (ELVIS effect) in inflammatory lesion and showed higher therapeutic efficacy than single-loaded nanoparticles, either free drug on its own, or a simple mixture of the two drugs.

Conclusion

This codelivery system based on HSA is a promising platform for combination chemotherapy in RA.

Alternative and Injectable Preformed Albumin-Bound Anticancer Drug Delivery System for Anticancer and Antimetastasis Treatment

Biomimetic design has been extensively investigated. The only FDA-approved biomimetic albumin-bound paclitaxel may not be beneficial to some treated patients due to rapid dissociation upon intravenous infusion and no substantial improvement in the drug's pharmacokinetics or biodistribution. Herein, we developed an alternative and injectable preformed albumin-bound anticancer drug delivery. We combined HSA, Kolliphor HS 15 (HS15), and pirarubicin (THP) via purely physical forces in a thin-film hydration method to obtain an albumin-bound complex of HSA-THP. The lack of any chemical reactions preserves HSA bioactivity, in contrast to the destroyed secondary structure within AN-THP (albumin nanoparticle of THP) for the harsh manipulation during preparation. In vitro, HSA-THP showed a significantly higher cellular uptake efficiency than THP, and the complex was more cytotoxic. In vivo, HSA-THP showed longer half-life than THP. It also exhibited greater tumor accumulation and tumor penetration via gp60- and SPARC-mediated biomimetic transport than THP and AN-THP. As a result, HSA-THP showed strong antitumor and antimetastasis efficacy, with relatively little toxicity. These results suggest the clinical potential of biomimetic tumor-targeted drug delivery.

Dual functional immunostimulatory polymeric prodrug carrier with pendent indoximod for enhanced cancer immunochemotherapy

Immunotherapy based on checkpoint blockade has been regarded as one of the most promising approaches towards many types of cancers. However, low response rate hinders its application due to insufficient tumor immunogenicity and immunosuppressive tumor microenvironment. To achieve an overall enhanced therapeutic outcome, we developed a dual-functional immuno-stimulatory polymeric prodrug carrier modified with pendent indoximod, an indoleamine 2,3-dioxygenase (IDO) inhibitor that can be used to reverse immune suppression, for co-delivery of Doxorubicin (Dox), a hydrophobic anticancer agent that can promote immunogenic cell death (ICD) and elicit antitumor immunity. The resulted carrier denoted as POEG-b-PVBIND, consisting of poly (oligo (ethylene glycol) methacrylate) (POEG) hydrophilic blocks and indoximod conjugated hydrophobic blocks, is rationally designed to improve immunotherapy by synergistically modulating the tumor microenvironment (TME). Our data showed that Dox-triggered ICD promoted intra-tumoral infiltration of CD8+ T cells and IFN-γ-production by CD8+ T cells. Meanwhile, cleaved indoximod significantly increased CD8+ T cell infiltration while reducing the immunosuppressive T regulatory cells (Tregs). More importantly, Dox/POEG-b-PVBIND micelles led to significantly improved tumor regression in an orthotopic murine breast cancer model compared to both Dox-loaded POEG-b-PVB micelles (a control inert carrier) and POEG-b-PVBIND micelles alone, confirming combination effect of indoximod and Dox in improving the overall antitumor activity. STATEMENT OF SIGNIFICANCE: Indoleamine 2,3-dioxygenase (IDO) is an enzyme that can induce immune suppressive microenvironment in tumors. As a well-studied IDO inhibitor, indoximod (IND) represents a promising agent for cancer immunotherapy and could be particularly useful in combination with other chemotherapeutic agents. However, three major problems hinder its application: (1) IND is barely soluble in water; (2) IND delivery efficiency is limited (3) simultaneous delivery of two agents into tumor site is still challenging. Currently, most reports largely focus on improving the pharmacokinetic profile of IND alone via different formulations such as IND prodrug and IND nanocrystal. However, there is limited information about IND based co-delivery systems, especially for delivering hydrophobic chemotherapeutic agents. Here, we developed a new dual-functional polymeric prodrug carrier modified with a number of pendent IND units (denoted as POEG-b-PVBIND). POEG-b-PVBIND shows immunostimulatory and antitumor activities by itself. More importantly, POEG-b-PVBIND polymer is able to self-assemble into nano-sized micelles that are highly effective in formulating and codelivering other hydrophobic agents including doxorubicin (Dox), sunitinib (Sun), and daunorubicin (Dau), which can elicit antitumor immunity via promoting immunogenic cell death (ICD). We have shown that our new combination therapy led to a significantly improved antitumor activity in an aggressive murine breast cancer model (4T1.2).

Co-delivery nanoparticles of doxorubicin and chloroquine for improving the anti-cancer effect in vitro

To increase the efficacy of small molecule chemotherapeutic drug (SMCD) and reduce its toxic and side effects, we selected two model drugs doxorubicin (DOX) and chloroquine (CQ). DOX is a SMCD and CQis a chemosensitizer with autophagy inhibition. Poly(lactic-co-glycolic acid) (PLGA) and alpha-tocopherol polyethylene glycol 1000 succinate were chosen as delivery carriers to design and prepare a novel type of drug co-delivery single-nanoparticles by emulsification-solvent volatilisation, named NP_DOX+CQ. The physicochemical properties of NP_DOX+CQ were characterised. Then A549 cells and A549/Taxol cells were used for the in vitro anti-cancer effect study. At the same time, cellular uptake, intracellular migration and anti-cancer mechanism of nanoparticles were studied. The NPs showed a uniform spherical shape with good dispersibility, and both drugs had good encapsulation efficiency and loading capacity. In all formulations, NP_DOX+CQ showed the highest in vitro cytotoxicity. The results showed that NPs could protect drugs from being recognised and excluded by P-glycoprotein (P-gp). Moreover, the results of the mechanistic study demonstrated that NPs were transported by autophagy process after being taken up by the cells. Therefore, during the migration of NP_DOX+CQ, CQ could exert its efficacy and block autophagy so that DOX would not be hit by autophagy. Western Blot results showed that NP_DOX+CQ had the best inhibition effect of autophagy. It can be concluded that the system can prevent the drug from being recognised and excluded by P-gp, and CQ blocks the process of autophagy so that the DOX is protected and more distributed to the nucleus of multidrug resistance (MDR) cell. The NP_DOX+CQ constructed in this study provides a feasible strategy for reversing MDR in tumour cells.

A theranostic agent for cancer therapy and imaging in the second near-infrared window

Theranostic nanoparticles are integrated systems useful for simultaneous diagnosis and imaging guided delivery of therapeutic drugs, with wide ranging potential applications in the clinic. Here we developed a theranostic nanoparticle (~ 24 nm size by dynamic light scattering) p-FE-PTX-FA based on polymeric micelle encapsulating an organic dye (FE) fluorescing in the 1,000-1,700 nm second near-infrared (NIR-II) window and an anti-cancer drug paclitaxel. Folic acid (FA) was conjugated to the nanoparticles to afford specific binding to molecular folate receptors on murine breast cancer 4T1 tumor cells. In vivo, the nanoparticles accumulated in 4T1 tumor through both passive and active targeting effect. Under an 808 nm laser excitation, fluorescence detection above 1,300 nm afforded a large Stokes shift, allowing targeted molecular imaging tumor with high signal to background ratios, reaching a high tumor to normal tissue signal ratio (T/NT) of (20.0 ± 2.3). Further, 4T1 tumors on mice were completed eradicated by paclitaxel released from p-FE-PTA-FA within 20 days of the first injection. Pharmacokinetics and histology studies indicated p-FE-PTX-FA had no obvious toxic side effects to major organs. This represented the first NIR-II theranostic agent developed.

Drug Exchange between Albumin Nanoparticles and Erythrocyte Membranes

The effects of thioridazine (TDZ) and chlorpromazine (CPZ) and bovine serum albumin nanoparticles (BSA-NPs) on erythrocyte membranes have been investigated. Two kinds of hemolytic assays were used; hemolysis under hypotonic conditions and hemolysis in physiological conditions. Under hypotonic conditions for 50% hemolysis, both TDZ and CPZ have a biphasic effect on membranes; namely, stabilization at low concentrations and destabilization after reaching a critical concentration. In physiological conditions, there are other critical concentrations above which both drugs hemolyse the erythrocites. In each case, the critical concentrations of TDZ are lower than those of CPZ, which is consistent with the ratio of their partition coefficients. When BSA-NPs are added to the erythrocyte suspension simultaneously with the drugs, the critical concentrations increase for both drugs. The effect is due to the incorporation of a portion of drug substances into the BSA-nanoparticles, which consequently leads to the decrease of the active drug concentrations in the erythrocyte suspension medium. Similar values of the critical concentrations are found when the BSA-NPs are loaded with the drugs before their addition to the erythrocyte suspension in which case the events of the partition are: desorption of the drug from BSA-NPs, diffusion through the medium, and adsorption on erythrocyte membranes. This result suggests that the drugs are not influenced by the processes of adsorption and desorption onto and out of the BSA-NPs, and that the use of BSA-NPs as drug transporters would allow intravenous administration of higher doses of the drug without the risk of erythrocyte hemolysis.

Chemosensitizer and docetaxel-loaded albumin nanoparticle: overcoming drug resistance and improving therapeutic efficacy

Aim: Investigated strategy exploits the utilization of quercetin as a chemosensitizer for docetaxel (DTX), which was incorporated into albumin nanoparticles (NPs; bovine serum albumin NPs [BSA–NPs]). Material & methods: BSA–NPs containing both drugs were optimized, extensively characterized for different quality attributes and performance was investigated using series of in vitro and in vivo investigations. Results: Co-encapsulated BSA–NPs exhibited size: 209.26 ± 9.84 nm, polydispersibility index: 0.184 ± 0.05 and good entrapment efficiency (∼75% for DTX and ∼68% for quercetin). Higher in vitro cytotoxicity, cell uptake and apoptosis were achieved in MCF-7 cell line. Similarly, higher P-glycoprotein efflux inhibition was observed in MDA-MB-231. About 2.5-fold increase in bioavailability of DTX was achieved with improved antitumor efficacy and reduced in vivo toxicity. Conclusion: Developed BSA–NPs provide an effective and safer alternative approach using co-delivery of chemosensitizer.

Engineering folate-targeting diselenide-containing triblock copolymer as a redox-responsive shell-sheddable micelle for antitumor therapy in vivo

The oxidation-reduction (redox)-responsive micelle system is based on a diselenide-containing triblock copolymer, poly(ε-caprolactone)-bis(diselenide-methoxy poly(ethylene glycol)/poly(ethylene glycol)-folate) [PCL-(SeSe-mPEG/PEG-FA)₂]. This has helped in the development of tumor-targeted delivery for hydrophobic anticancer drugs. The diselenide bond, as a redox-sensitive linkage, was designed in such a manner that it is located at the hydrophilic-hydrophobic hinge to allow complete collapse of the micelle and thus efficient drug release in redox environments. The amphiphilic block copolymers self-assembled into micelles at concentrations higher than the critical micelle concentration (CMC) in an aqueous environment. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) analyses showed that the micelles were spherical with an average diameter of 120 nm. The insoluble anticancer drug paclitaxel (PTX) was loaded into micelles, and its triggered release behavior under different redox conditions was verified. Folate-targeting micelles showed an enhanced uptake in 4T1 breast cancer cells and in vitro cytotoxicity by flow cytometry and (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay, respectively. Delayed tumor growth was confirmed in the subcutaneously implanted 4T1 breast cancer in mice after intraperitoneal injection. The proposed redox-responsive copolymer offers a new type of biomaterial for drug delivery into cancer cells in vivo.

STATEMENT OF SIGNIFICANCE

On-demand drug actuation is highly desired. Redox-responsive polymeric DDSs have been shown to be able to respond and release their cargo in a selective manner when encountering a significant change in the potential difference, such as that present between cancerous and healthy tissues. This study offers an added advantage to the field of redox-responsive polymers by reporting a new type of shell-sheddable micelle based on an amphiphilic triblock co-polymer, containing diselenide as a redox-sensitive linkage. The linkage was smartly located at the hydrophilic-hydrophilic bridge in the co-polymer offering complete collapse of the micelle when exposed to the right trigger. The system was able to delay tumor growth and reduce toxicity in a breast cancer tumor model following intraperitoneal injection in mice.

Development of a novel morphological paclitaxel-loaded PLGA microspheres for effective cancer therapy: in vitro and in vivo evaluations

Sustained release of therapeutic agents into tumor cells is a potential approach to improve therapeutic efficacy, decrease side effects, and the drug administration frequency. Herein, we used the modified double-emulsion solvent evaporation (DSE) method to prepare a novel morphological paclitaxel (PTX) loaded poly(lactide-co-glycolide) (PLGA) microspheres (MS). The prepared rough PTX-PLGA-MS possessed microporous surface and highly porous internal structures, which significantly influenced the drug entrapment and release behaviors. The rough MS with an average particle size of 53.47 ± 2.87 μm achieved high drug loading (15.63%) and encapsulation efficiency (92.82%), and provided a favorable sustained drug release. The in vitro antitumor tests of flow cytometry and fluoroimmunoassay revealed that the rough PTX-PLGA-MS displayed effective anti-gliomas activity and enhanced the cellular PTX uptake through adsorptive endocytosis. Both in vitro and in vivo antitumor results demonstrated that the sustained-release PTX could induce the microtubules assembly and the over-expression of Bax and Cyclin B1 proteins, resulting in the microtubule dynamics disruption, G2/M phase arrest, and cell apoptosis accordingly. Furthermore, as the rough PTX-PLGA-MS could disperse and adhere throughout the tumor sites and cause extensive tumor cell apoptosis with one therapeutic course (12 days), they could reduce the system toxicity and drug administration frequency, thus achieving significant tumor inhibitory effects with rapid sustained drug release. In conclusion, our results verified that the rough PTX-PLGA-MS drug release system could serve as a promising treatment to malignant glioma.

Combinational drug delivery using nanocarriers for breast cancer treatments: A review

Breast cancer (BC) is the most common cancer in women that requires special attention due to low response to conventional treatments. The common method for treating cancer (especially BC) is applying a single anticancer agent, however, due to some disadvantages including cytotoxicity, side effects, and multidrug resistance, the efficiency and application of this method are limited. To overcome these challenges, the combinational delivery of anticancer drugs (including chemical agents, genetic materials, etc.) has been introduced. To increase the efficacy of this new method, several nanocarriers including inorganic nanoparticles (such as, magnetic nanoparticles, silica nanoparticles, etc.) and organic ones (e.g., dendrimers, liposomes, micelles, and polymeric nanoparticles) have been used. Based on the literature, combinational delivery using nanocarriers showed promising results in the treatment of BC. In this review, combination regimens for the treatment of BC, nanocarriers containing combinations of pharmaceutical agents (including small molecule chemotherapeutic, biological, and gene therapy agents) as an opportunity to overcome chemotherapy challenges and, finally, examples of these formulations have been presented. This review aims to provide a better understanding of these increasingly important new methods of cancer treatment and the main issues and key considerations for a rational design of nanocarriers used in combinational delivery of different synergistic anticancer agents. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2272-2283, 2018.

Combination of doxorubicin with harmine-loaded liposomes exerting synergistic antitumor efficacy

CONTEXT

Long-circulation (PEGLip), pH-sensitive (PEOzLip), and active targeted liposomes (PEG-TATLip)-loading doxorubicin (DOX) and harmine (HM) were prepared. Their physicochemical properties and antitumor effect were investigated.

OBJECTIVES

The aims of the present study were to evaluate synergistic antitumor efficacy.

MATERIALS AND METHODS

Liposomes were prepared by using thin-film dispersion, active drug-loading and target post-insertion method. Subsequently physiochemical properties including particle size distribution, zeta potential, entrapment efficiency (EE), drug-loading content and in-vitro release were determined. Besides, the in vitro cytotoxicity of free drugs and drug-loaded liposomes was explored by using a Sulforhodamine-B Staining assay and the combination index values (CI Value) were calculated. Finally, the cellular uptake experiments by MCF-7cells were carried out via flow cytometry.

RESULTS AND DISCUSSION

All liposomes enhanced the antitumor effect significantly compared to free drugs. Among liposomes, PEG-TATLip enhanced the antitumor effect significantly compared to others. DOX and HM had moderate synergism with CI Value 0.85 for free drugs, 0.81 for PEGLip, 0.72 for PEOzLip, and 0.84 for PEG-TATLip respectively when the weight ratio of two drugs was 1:2. Moreover, the similarity between DOX and HM such as physicochemical properties, in vitro release modes and in vitro uptake kinetics characteristics when they were in the same formulations proved it possible for them to be delivered together.

CONCLUSION

Active targeting liposomes were the most effective delivery system as compared with pH-sensitive and long circulation liposomes. Additionally, DOX and HM could be co-delivered in liposomes and they could play moderate synergism effect in antitumor efficacy.

A water-soluble nucleolin aptamer-paclitaxel conjugate for tumor-specific targeting in ovarian cancer

Paclitaxel (PTX) is among the most commonly used first-line drugs for cancer chemotherapy. However, its poor water solubility and indiscriminate distribution in normal tissues remain clinical challenges. Here we design and synthesize a highly water-soluble nucleolin aptamer-paclitaxel conjugate (NucA-PTX) that selectively delivers PTX to the tumor site. By connecting a tumor-targeting nucleolin aptamer (NucA) to the active hydroxyl group at 2' position of PTX via a cathepsin B sensitive dipeptide bond, NucA-PTX remains stable and inactive in the circulation. NucA facilitates the uptake of the conjugated PTX specifically in tumor cells. Once inside cells, the dipeptide bond linker of NucA-PTX is cleaved by cathepsin B and then the conjugated PTX is released for action. The NucA modification assists the selective accumulation of the conjugated PTX in ovarian tumor tissue rather than normal tissues, and subsequently resulting in notably improved antitumor activity and reduced toxicity.

Inducing Controlled Release and Increased Tumor-Targeted Delivery of Chlorambucil via Albumin/Liposome Hybrid Nanoparticles

Liposomes possess good biocompatibility and excellent tumor-targeting capacity. However, the rapid premature release of lipophilic drugs from the lipid bilayer of liposomes has negative effect on the tumor-targeted drug delivery of liposomes. In this study, a lipophilic antitumor drug-chlorambucil (CHL)-was encapsulated into the aqueous interior of liposomes with the aid of albumin to obtain the CHL-loaded liposomes/albumin hybrid nanoparticles (CHL-Hybrids). The in vitro accumulative release rate of CHL from CHL-Hybrids was less than 50% within 48 h, while the accumulative CHL release was more than 80% for CHL-loaded liposomes (CHL-Lip). After intravenous injection into rats, the half-life (t _1/2β = 5.68 h) and maximum blood concentration (C _max = 4.58 μg/mL) of CHL-Hybrids were respectively 1.1 times and 3.5 times higher than that of CHL-Lip. In addition, CHL-Hybrids had better tumor-targeting capacity for it significantly increased the drug accumulation in B16F10 tumors, which contributed to the significantly control of tumor growth compared with CHL-Lip. Furthermore, CHL-Hybrid-treated B16F10 melanoma-bearing mice displayed the longest median survival time of 30.0 days among all the treated groups. Our results illustrated that the proposed hybrids drug delivery system would be a promising strategy to maintain the controlled release of lipophilic antitumor drugs from liposomes and simultaneously facilitate the tumor-targeted drug delivery.

Co-delivery nanoparticles of anti-cancer drugs for improving chemotherapy efficacy

To achieve superior therapeutic efficacy, the combination chemotherapy using two or more anticancer drugs in clinical practice has been generally accepted as a feasible strategy. On account of the concept of combination chemotherapy, co-delivery of anticancer drugs with nanotechnology gradually becomes a desired strategy and one of the research frontiers on modern drug delivery. In recent years, nano drug co-delivery system (NDCDS), which loads at least two anticancer drugs with different physicochemical and pharmacological properties into a combination delivery system, has achieved rapid development. NDCDS synergistically inhibited the growth of the tumor compared with the free drugs. In this review, we highlighted the current state of co-delivery nanoparticles and the most commonly used nanomaterial, discussed challenges and strategies, and prospect future development.

Targeted delivery of celastrol to mesangial cells is effective against mesangioproliferative glomerulonephritis

Mesangial cells-mediated glomerulonephritis is a frequent cause of end-stage renal disease. Here, we show that celastrol is effective in treating both reversible and irreversible mesangioproliferative glomerulonephritis in rat models, but find that its off-target distributions cause severe systemic toxicity. We thus target celastrol to mesangial cells using albumin nanoparticles. Celastrol-albumin nanoparticles crosses fenestrated endothelium and accumulates in mesangial cells, alleviating proteinuria, inflammation, glomerular hypercellularity, and excessive extracellular matrix deposition in rat anti-Thy1.1 nephritis models. Celastrol-albumin nanoparticles presents lower drug accumulation than free celastrol in off-target organs and tissues, thereby minimizing celastrol-related systemic toxicity. Celastrol-albumin nanoparticles thus represents a promising treatment option for mesangioproliferative glomerulonephritis and similar glomerular diseases.

Mesangial cell-mediated glomerulonephritis is a frequent cause of kidney disease. Here the authors show that celastrol loaded in albumin nanoparticles efficiently targets mesangial cells, and is effective in rat models.

Strategies for Preparing Albumin-based Nanoparticles for Multifunctional Bioimaging and Drug Delivery

Biosafety is the primary concern in clinical translation of nanomedicine. As an intrinsic ingredient of human blood without immunogenicity and encouraged by its successful clinical application in Abraxane, albumin has been regarded as a promising material to produce nanoparticles for bioimaging and drug delivery. The strategies for synthesizing albumin-based nanoparticles could be generally categorized into five classes: template, nanocarrier, scaffold, stabilizer and albumin-polymer conjugate. This review introduces approaches utilizing albumin in the preparation of nanoparticles and thereby provides scientists with knowledge of goal-driven design on albumin-based nanomedicine.