Fabrication of a nanocarrier system through self-assembly of plasma protein and its tumor targeting

Fighting against Drug-Resistant Tumor by the Induction of Excessive Mitophagy with Transferrin Nanomedicine

The effectiveness of chemotherapy is primarily hindered by drug resistance, and autophagy plays a crucial role in overcoming this resistance. In this project, a human transferrin nanomedicine contains quercetin (a drug to induce excessive autophagy) and doxorubicin is developed (HTf@DOX/Qu NPs). The purpose of this nanomedicine is to enhance mitophagy and combating drug-resistant cancer. Through in vitro studies, it is demonstrated that HTf@DOX/Qu NPs can effectively downregulate cyclooxygenase-2 (COX-2), leading to an excessive promotion of mitophagy and subsequent mitochondrial dysfunction via the PENT-induced putative kinase 1 (PINK1)/Parkin axis. Additionally, HTf@DOX/Qu NPs can upregulate proapoptotic proteins to induce cellular apoptosis, thereby effectively reversing drug resistance. Furthermore, in vivo results have shown that HTf@DOX/Qu NPs exhibit prolonged circulation in the bloodstream, enhanced drug accumulation in tumors, and superior therapeutic efficacy compared to individual chemotherapy in a drug-resistant tumor model. This study presents a promising strategy for combating multidrug-resistant cancers by exacerbating mitophagy through the use of transferrin nanoparticles.

Long-term and liver-selected ginsenoside C-K nanoparticles retard NAFLD progression by restoring lipid homeostasis

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent hepatic disease characterized as lipid accumulation, yet without any approved drug. And development of therapeutic molecules is obstructed by low efficiency and organ toxicity. Herein, we develop a long-term, low-toxic and liver-selected nano candidate, nabCK, to alleviate NAFLD. NabCK is simply composed by natural compound ginsenoside compound K (CK) and albumin. As a major metabolite of ginseng, ginsenoside CK has excellently modulating functions for lipid metabolism, but accompanied by an extremely poor bioavailability <1%. Albumin is a key lipid carrier secreted and metabolized by livers. Thereby, it can improve solubility and liver-localization of CK. In adipocytes and hepatocytes, nabCK prevents lipid deposition and eliminates lipid droplets. Transcriptomic analysis reveals that nabCK rectifies various pathways that involved in steatosis development, including lipid absorption, lipid export, fatty acid biosynthesis, lipid storage and inflammation. All these pathways are modulated by mTOR, the pivotal feedback sensor that is hyperactive in NAFLD. NabCK suppresses mTOR activation to restores lipid homeostasis. In high-fat diet (HFD) induced NAFLD mice, nabCK retards development of steatosis and fibrosis, coupling a protective effect on cardiac tissues from lipotoxicity. Together, nabCK is a safe and potent candidate to offer benefits for NAFLD treatment.

Rapid generation of homogenous tumor spheroid microtissues in a scaffold-free platform for high-throughput screening of a novel combination nanomedicine

Combination nanomedicine is a potent strategy for cancer treatment. Exploiting different mechanisms of action, a novel triple drug delivery system of 5-fluorouracil, curcumin, and piperine co-loaded human serum albumin nanoparticles (5FU-CUR-PIP-HSA-NPs) was developed via the self-assembly method for suppressing breast tumor. Both hydrophobic and hydrophilic drugs were successfully encapsulated in the HSA NPs with a high drug loading efficiency (DLE) of 10%. Successful clinical translation of nanomedicines, however, is a challenging process requiring considerable preclinical in vitro and in vivo animal tests. The aim of this study was to develop a homemade preclinical 3D culture model in the standard 96-well plates in a cost and time-effective novel approach for the rapid generation of homogenous compact tumor spheroids for disease modeling, and anticancer therapeutic/nanomedicine screening. The knowledge of drug screening can be enhanced by employing such a model in a high-throughput manner. Accordingly, to validate the formulated drug delivery system and investigate the cellular uptake and cytotoxicity effect of the nanoformulation, 3D tumor spheroids were employed. The practicality of the nanomedicine system was substantiated in different tests. The in vitro uptake of the NPs into the tight 3D tumor spheroids was facilitated by the semi-spherical shape of the NPs with a proper size and surface charge. 5FU-CUR-PIP-HSA-NPs demonstrated high potency of migration inhibition as a part of successful anti-metastatic therapy as well. The remarkable differences in 2D and 3D cytotoxicities emphasize the importance of employing 3D tumor models as an intermediate step prior to in vivo animal experiments for drug/nanomedicine screening.

Nanoparticle-containing lyophilized dry powder inhaler formulations optimized using central composite design with improved aerodynamic parameters and redispersibility

Objectives: The aim of this study was to improve the aerodynamic behavior and redispersibility of a lyophilized dry powder inhaler (DPI) formulation containing nanoparticles.Methods: Paclitaxel (PTX)-human serum albumin (HSA) nanoparticles were used as a model, and DPIs containing the nanoparticles were produced by lyophilization using different carriers and carrier ratios. A central composite design was employed to optimize the formulation. L-leucine and mannitol were chosen as independent variables, and mass median aerodynamic diameter (MMAD), emitted fraction, fine particle fraction (FPF), nanoparticle size, polydispersity index (PDI), zeta potential were selected as dependent variables.Results: The water content of DPIs was less than 5% for all DPIs. The cytotoxicity of the DPIs, determined using A549 cells, was due to PTX alone. Particle sizes of 204.3 ± 1.65 nm and 94.3-1353.0 nm were obtained before and after lyophilization, respectively. The developed method resulted in a reduction in the MMAD from 8.148 µm to 5.274 µm, an increase in the FPF from 17.63% to 33.60%, and an increase in the emitted fraction from 77.68% to 97.03%. The physico-chemical characteristics of the optimized formulation were also assessed.Conclusions: In conclusion, this study demonstrates that lyophilization can be used to produce nanoparticle-containing DPI formulations with improved redispersibility and aerodynamic properties.

4-Chloro-1,2-phenylenediamine induced structural perturbation and genotoxic aggregation in human serum albumin

4-Chloro-1,2-phenylenediamine (4-Cl-OPD) is a halogenated aromatic diamine used as a precursor in permanent hair color production. Despite its well-documented mutagenic and carcinogenic effects in various in vitro and in vivo models, its role in fibrillar aggregate formation and their genotoxic effect in therapeutic proteins has received less attention. The significance of human serum albumin (HSA) arises from its involvement in bio-regulatory and transport processes. HSA misfolding and aggregation are responsible for some of the most frequent neurodegenerative disorders. We used various complementary approaches to track the formation of amyloid fibrils and their genotoxic effect. Molecular dynamics study demonstrated the complex stability. The impact of 4-Cl-OPD on the structural dynamics of HSA was confirmed by Raman spectroscopy, X-ray diffraction, HPLC and SDS-PAGE. Fibrilllar aggregates were investigated using Congo red assay, DLS, and SEM. The genotoxic nature of 4-Cl-OPD was confirmed using plasmid nicking assay and DAPI staining, which revealed DNA damage and cell apoptosis. 4-Cl-OPD provides a model system for studying fibrillar aggregation and their genotoxic potential in the current investigation. Future studies should investigate the inhibition of the aggregation/fibrillation process, which may yield valuable clinical insights.

Olaparib@human serum albumin nanoparticles as sustained drug-releasing tumor-targeting nanomedicine to inhibit growth and metastasis in the mouse model of triple-negative breast cancer

Poly(ADP-ribose) polymerase inhibitor olaparib demonstrated therapeutic effectiveness in highly metastatic triple-negative breast cancer (TNBC). However, olaparib offers a weak therapeutic response in wild-type BRCA cancers due to the drug's poor bioavailability. Here, a bioinspired/active-tumor targeted nanoparticles system of human serum albumin with physical entrapment of olaparib was prepared via a low-energy desolvation technique using the crosslinker glutaraldehyde. The developed OLA@HSA NPs were nanosize (∼140 nm), kinetically stable with a low polydispersity (0.3), exhibited olaparib entrapment (EE 76.01 ± 2.53%, DL 6.76 ± 0.22%), and sustained drug release at pH 7.4 with an enhancement of drug release in acidic pH. OLA@HSA NPs decreased the half-maximal inhibitory concentrations (IC₅₀) of olaparib by 1.6, 1.8-fold in 24 h and 2.2, 2.4 folds in 48 h for human (MDA-MB 231) and mouse (4T1) TNBC cells, respectively, mediated by their enhanced time-dependent cellular uptake than free olaparib. The OLA@HSA-OA NPs induced concentration-dependent phosphatidylserine (apoptotic marker) externalization and arrested the cell population in the G2/M phase in both the tested cell lines at a higher level than free olaparib. The NPs formulation increased DNA fragmentation, mitochondrial membrane depolarization, and ROS generation than the free olaparib. The in vivo study conducted using 4T1-Luc tumor-bearing mice demonstrated strong tumor growth inhibitory potential of OLA@HSA NPs by elevating apoptosis ROS generation and reducing the level of the antiproliferative marker, Ki-67. OLA@HSA NPs reduced the occurrence of lung metastasis (formation of metastasis nodules decreased by ∼10 fold). OLA@HSA NPs could be a promising nanomedicine for the TNBC treatment.

Peptide Modified Albumin-Paclitaxel Nanoparticles for Improving Chemotherapy and Preventing Metastasis

Metastasis and recurrence are the main causes of death in cancer patients, however, there are few medicines which could inhibit tumor growth and metastasis at the same time. In this work, we reported a novel nano-drug delivery system (NDDS) based on targeting ligand modified albumin. The hydrophobic drug (paclitaxel) induced albumin self-assembly after treatment of albumin with L-cysteine, forming drug-loaded nanoparticles with a size of 100-200 nm. Importantly, the albumin nanoparticles displayed enhanced antitumor efficacy against tumor growth/lung metastasis in 4T1 bearing nude mice and prevention of lung metastasis in a B16-F10 model. This study provides a facile method for hydrophobic chemo-drugs loaded albumin nanoparticles preparation and a promising chemotherapy with effective tumor growth inhibition and metastasis prevention. This article is protected by copyright. All rights reserved.

Synergistic Effect of Self-Assembled Curcumin and Piperine Co-Loaded Human Serum Albumin Nanoparticles on Suppressing Cancer Cells

OBJECTIVE

The combinational therapy is often considered as a desire in chemotherapy despite some limitations. This study aimed to encapsulate two natural-based drugs, curcumin (CUR), and piperine (PIP) into highly biocompatible albumin nanoparticles for anticancer applications.

SIGNIFICANCE

A simultaneous exertion of CUR and PIP in a biocompatible drug delivery system with the minimum side effects and no limitations was achievable in this work for cancer treatment.

METHODS

Curcumin and piperine co-loaded human serum albumin nanoparticles (CUR-PIP-HSA-NPs) were synthesized by the self-assembly method. The effectiveness of the codelivery system was evaluated physically, chemically, and pharmaceutically. Moreover, the anticancer activity of CUR-PIP-HSA-NPs was studied on MCF-7 cells by MTT assay.

RESULTS

CUR-PIP-HSA-NPs showed appropriate stability with an average particle size of 154.7 ± 5.2 nm. Loading of drugs was demonstrated by Fourier transform infrared (FT-IR) and differential scanning calorimetry (DSC) analyses. The drug encapsulation efficiencies (DEEs) of CUR and PIP in NPs were 85.3% ± 1.46% and 81.7%, ± 1.67%, respectively. Furthermore, the drug loading efficiency (DLE) of CUR-PIP-HSA-NPs was 8.71% ± 0.24%. The circular dichroism (CD) examination of the NPs confirmed that the conformational structure of albumin remained unchanged during the synthesis. In addition, the cytotoxicity experiments demonstrated the high potential of CUR-PIP-HSA-NPs against breast cancer (MCF-7) cells in the presence of PIP as both bioenhancer and anticancer drug with the capability of suppressing the effect of multidrug resistance (MDR).

CONCLUSIONS

The results suggest that CUR-PIP-HSA-NPs can be employed as a practical drug delivery system in cancer treatment with synergistic effects of both CUR and PIP.

Internal cross-linked polymeric nanoparticles with dual sensitivity for combination therapy of muscle-invasive bladder cancer

Background

Chemotherapy is a standard cancer treatment which uses anti-cancer drugs to destroy or slow the growth of cancer cells. However, chemotherapy has limited therapeutic effects in bladder cancer. One of the reasons of this resistance to chemotherapy is that higher levels of glutathione in invasive bladder cancer cells. We have fabricated nanoparticles that respond to high concentrations of glutathione and near-infrared laser irradiation in order to increase the drug accumulation at the tumor sites and combine chemotherapy with photothermal therapy to overcome the challenges of bladder cancer treatment.

Methods

The DOX&IR780@PEG-PCL-SS NPs were prepared by co-precipitation method. We investigated the tumor targeting capability of NPs in vitro and in vivo. The orthotopic bladder cancer model in C57BL/6 mice was established for in vivo study and the photothermal effects and therapeutic efficacy of NPs were evaluated.

Results

The DOX&IR780@PEG-PCL-SS NPs were synthesized using internal cross-linking strategy to increase the stability of nanoparticles. Nanoparticles can be ingested by tumor cells in a short time. The DOX&IR780@PEG-PCL-SS NPs have dual sensitivity to high levels of glutathione in bladder cancer cells and near-infrared laser irradiation. Glutathione triggers chemical structural changes of nanoparticles and preliminarily releases drugs, Near-infrared laser irradiation can promote the complete release of the drugs from the nanoparticles and induce a photothermal effect, leading to destroying the tumor cells. Given the excellent tumor-targeting ability and negligible toxicity to normal tissue, DOX&IR780@PEG-PCL-SS NPs can greatly increase the concentration of the anti-cancer drugs in tumor cells. The mice treated with DOX&IR780@PEG-PCL-SS NPs have a significant reduction in tumor volume. The DOX&IR780@PEG-PCL-SS NPs can be tracked by in vivo imaging system and have good tumor targeting ability, to facilitate our assessment during the experiment.

Conclusion

A nanoparticle delivery system with dual sensitivity to glutathione and near-infrared laser irradiation was developed for delivering IR780 and DOX. Chemo-photothermal synergistic therapy of both primary bladder cancer and their metastases was achieved using this advanced delivery system.

A novel nanoparticle drug delivery system based on PEGylated hemoglobin for cancer therapy

Proteins such as albumin, gelatin, casein, transferrin, and collagen are widely used as drug delivery systems. However, only albumin-based paclitaxel (PTX) formulation Abraxane^® (PTX-albumin NPs prepared by nab-technology) has been successfully developed for treating metastatic breast cancer clinically due to abundant materials, simple industrial scale-up process, and well tumor-targeting ability. Hemoglobin (Hb) is another protein used for drug delivery with similar advantages. In this study, we successfully synthesized PEG-Hb nanoparticles loading with PTX based on previously well-established acid-denatured method. PEG-Hb-PTX NPs showed enhanced cellular uptake and great cellular inhibition ability in vitro. Moreover, our animal study showed that PEGylated NPs greatly accumulated in tumor tissues and exhibited excellent anticancer activity in vivo. We found that PEG-Hb-PTX NPs possess a better in vivo antitumor effect than the commercially available Taxol^® formulation. We believe that PEG-Hb has great potential as an efficient drug delivery system for further clinic study.

Thiol-water proton exchange of glutathione, cysteine, and N-acetylcysteine: Implications for CEST MRI

Amide-, amine-, and hydroxyl-water proton exchange can generate MRI contrast through chemical exchange saturation transfer (CEST). In this study, we show that thiol-water proton exchange can also generate quantifiable CEST effects under near-physiological conditions (pH = 7.2 and 37°C) through the characterization of the pH dependence of thiol proton exchange in phosphate-buffered solutions of glutathione, cysteine, and N-acetylcysteine. The spontaneous, base-catalyzed, and buffer-catalyzed exchange contributions to the thiol exchange were analyzed. The thiol-water proton exchange of glutathione and cysteine was found to be too fast to generate a CEST effect around neutral pH due to significant base catalysis. The thiol-water proton exchange of N-acetylcysteine was found to be much slower, yet still in the fast-exchange regime with significant base and buffer catalysis, resulting in a 9.5% attenuation of the water signal at pH 7.2 in a slice-selective CEST NMR experiment. Furthermore, the N-acetylcysteine thiol CEST was also detectable in human serum albumin and agarose phantoms.

A comparative and systematic approach to desolvation and self-assembly methods for synthesis of piperine-loaded human serum albumin nanoparticles

The present work aimed to accomplish a comparative and principled study on desolvation and self-assembly methods for synthesis of piperine-loaded human serum albumin nanoparticles (PIP-HSA-NPs). Among drugs, PIP was selected as the hydrophobic model drug. The response surface methodology (RSM)-central composite design (CCD) was employed to precisely study the processes and the interactions between the factors affecting the methods. Optimization was performed to obtain the best formulations for both procedures. Both optimized PIP-HSA-NPs prepared by the two methods were stable and semi-spherical with the size less than 200 nm. The self-assembled PIP-HSA-NPs which were prepared under the optimized conditions with drug encapsulation efficiency (DEE) of 76.8% ± 0.44%, and drug loading efficiency (DLE) of 8.92% ± 0.3% had significantly higher DEE and DLE than the optimized particles obtained from the desolvation method with DEE of 34.1% ± 0.32% and DLE of 1.68 ± 0.11%. The secondary structure of HSA did not change much in self-assembled PIP-HSA-NPs compared to desolvated PIP-HSA-NPs. The self-assembled PIP-HSA-NPs showed more cumulative drug release than desolvated NPs, causing them to have more cytotoxicity on MCF-7 cells at high concentrations. These findings introduce the self-assembly technique as the better chemical method to produce a practical cost-effective carrier for many hydrophobic drugs.

Perfluorocarbon regulates the intratumoural environment to enhance hypoxia-based agent efficacy

Hypoxia-based agents (HBAs), such as anaerobic bacteria and bioreductive prodrugs, require both a permeable and hypoxic intratumoural environment to be fully effective. To solve this problem, herein, we report that perfluorocarbon nanoparticles (PNPs) can be used to create a long-lasting, penetrable and hypoxic tumour microenvironment for ensuring both the delivery and activation of subsequently administered HBAs. In addition to the increased permeability and enhanced hypoxia caused by the PNPs, the PNPs can be retained to further achieve the long-term inhibition of intratumoural O₂ reperfusion while enhancing HBA accumulation for over 24 h. Therefore, perfluorocarbon materials may have great potential for reigniting clinical research on hypoxia-based drugs.

Hypoxia-based agents need permeable and hypoxic intratumour environment to be effective. Here, the authors show that perfluorocarbon nanoparticles promote increased permeability and sustained hypoxia to improve accumulation of hypoxia-based agents, and inhibit intratumour oxygen reperfusion.

Translatable High Drug Loading Drug Delivery Systems Based on Biocompatible Polymer Nanocarriers

Most nanocarriers possess low drug loading, resulting in frequently repeated administration and thereby high cost and increased side effects. Furthermore, the characteristics of nanocarrier materials, especially the drug loading capacity, plays a vital role in the drug delivery efficacy. In this review, we focus on the readily translatable polymeric drug delivery systems with high drug loading, which are comprised of biocompatible polymers such as poly(ethylene glycol), poly( N-vinylpyrrolidone), polyoxazoline, natural proteins like albumin and casein, non-natural proteins such as recombinant elastin-like polypeptides, as well as nucleic acids. At the end of this review, applications of these polymeric nanocarriers on the delivery of proteins and gene drugs are also briefly discussed.

Self-assembled hemoglobin nanoparticles for improved oral photosensitizer delivery and oral photothermal therapy in vivo

AIM

The aim of the present study was to use hemoglobin (Hb) nanoparticles (NPs) to improve oral bioavailability of a near-infrared dye IR780 for in vivo antitumor application in photothermal therapy.

METHODS

One-step acid-denaturing method was used to encapsulate IR780 into self-assembled Hb NPs (IR780@Hb NPs). Pharmacokinetics, biodistribution and antitumor effect were studied in vivo.

RESULTS

The Hb NPs showed high stability in enzymatic and acidic conditions similar to the gastric environment, and enhanced absorption of IR780 into the blood. In vivo imaging revealed that IR780 could accumulate at the tumor sites and effectively caused photothermal effect, which resulted in tumor ablation after oral administration in tumor-bearing mice.

CONCLUSION

Hb NPs represent a promising delivery system for improving oral absorption of photosensitizer dyes, which could open new treatment modalities in cancer.

Redox responsive albumin autogenic nanoparticles for the delivery of cancer drugs

The present study explores preparation and characterization of redox sensitive albumin autogenic nanoparticles (ANPs) for drug delivery applications. Human serum albumin nanoparticles are prepared by desolvation method. The particles are stabilized through self-crosslinking and no external stabilizers are involved in the preparation. ANPs are then subjected to Camptothecin (CPT) drug loading. Experiments on in vitro and in vivo release profile, cytotoxic and cytocompatability, hemocompatability, blood clearance, tracking and bio imaging are studied in detail. The redox sensitive and drug release properties of ANPs studied in the presence of glutathione. Results on the physical, chemical and instrumental characterization warrant the property of the nanoparticles. ANPs obtained in the present study is biocompatible, biodegradable, effectively entangle the chosen drug, release the drug in the controlled manner, sensitive to reducing environment, nil toxicity and appreciable uptake by cells. In the current scenario on the requirement of a drug carrier with redox sensitive property to encounter cancer cells, the results of the present study on albumin nanoparticles with redox sensitivity is smart and pave the way in the cancer therapeutics.

Targeted delivery and release of doxorubicin using a pH-responsive and self-assembling copolymer

We developed a pH-response copolymer that entrapped DOX into its hydrophobic core and self-assembles into smart DOX-loaded nanoparticles, which could enhance cancer-targeting and effective drug release in tumors.

Self-assembled albumin nanoparticles as a nanocarrier for aclacinomycin A

This study aimed to reduce the cytotoxicity and improve the targeting of aclacinomycin (ACM) by covalently coupling it with amino-oxyacetic acid (AOA) to generate an active intermediate, AOA-ACM. AOA-ACM was conjugated with self-assembled human serum albumin (HSA) nanoparticles constructed using tris(2-carboxyethyl)phosphine (TCEP) as disulfide bond breaking molecules in an 'opening stage-intermediate-closing stage' route, in which the hydrophobic interaction, interchange of sulfhydryl and hydrogen bond may be the key factors in the assembling process. Conjugation between ACM and albumin nanoparticles was found to occur at an ACM ketone site using ¹H-NMR and ¹³C-NMR matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass analysis indicated that the drug loading efficiency of ACM conjugated with HSA nanoparticles (NPs-ACM) was 7.4% (molar ratio = 6:1). The release of NPs-ACM was pH dependent. In vivo studies indicated that NPs-ACM exhibited fourfold higher tumor targeting capability on S180-tumor-bearing mice compared with the free ACM (p < 0.05). The cytotoxictiy and cardiotoxicity of NPs-ACM was reduced compared with the free ACM. Albumin carrier altered the blood pharmacokinetics and distribution of ACM. Hence, the NPs-ACM prodrug is ideal tumor targeting drug carriers for ACM, and the easy approach developed in this study for active intermediate and prodrug preparation can be applied to other pharmacological substances containing ketone groups. The method of preparing HSA-blank nanoparticles through TCEP reduction could be adopted to improve the water solubility of lipophilic drugs and their tumor-targeting specificity by fabricating HSA-lipophilic drug nanoparticles.

Self-assembled IR780-loaded transferrin nanoparticles as an imaging, targeting and PDT/PTT agent for cancer therapy

Combination of photothermal and photodynamic therapy (PTT/PDT) offer unique advantages over PDT alone. However, to achieve synergetic PDT/PTT effect, one generally needs two lasers with different wavelengths. Near-infrared dye IR-780 could be used as photosensitizer both for PTT and PDT, but its lipophilicity limits its practical use and in vivo efficiency. Herein, a simple multifunctional IR780-loaded nanoplatform based on transferrin was developed for targeted imaging and phototherapy of cancer compatible with a single-NIR-laser irradiation. The self-assembled transferrin-IR780 nanoparticles (Tf-IR780 NPs) exhibited narrow size distribution, good photo-stability, and encouraging photothermal performance with enhanced generation of ROS under laser irradiation. Following intravenous injection, Tf-IR780 NPs had a high tumor-to-background ratio in CT26 tumor-bearing mice. Treatment with Tf-IR780 NPs resulted in significant tumor suppression. Overall, the Tf-IR780 NPs show notable targeting and theranostic potential in cancer therapy.

Acid Denaturation Inducing Self-Assembly of Curcumin-Loaded Hemoglobin Nanoparticles

Hemoglobin is a promising drug carrier but lacks extensive investigation. The chemical conjugation of hemoglobin and drugs is costly and complex, so we have developed curcumin-loaded hemoglobin nanoparticles (CCM-Hb-NPs) via self-assembly for the first time. Using the acid-denaturing method, we avoid introducing denaturants and organic solvents. The nanoparticles are stable with uniform size. We have conducted a series of experiments to examine the interaction of hemoglobin and CCM, including hydrophobic characterization, SDS-PAGE. These experiments substantiate that this self-assembly process is mainly driven by hydrophobic forces. Our nanoparticles achieve much higher cell uptake efficiency and cytotoxicity than free CCM solution in vitro. The uptake inhibition experiments also demonstrate that our nanoparticles were incorporated via the classic clathrin-mediated endocytosis pathway. These results indicate that hemoglobin nanoparticles formed by self-assembly are a promising drug delivery system for cancer therapy.

Enhanced tolerance and antitumor efficacy by docetaxel-loaded albumin nanoparticles

Docetaxel is one of the most active chemotherapeutic agents for cancer treatment. The traditional docetaxel injection (TAXOTERE®) is currently formulated in the surfactant polysorbate 80, which has been associated with severe adverse reactions. To avoid the use of polysorbate 80 as well as to reduce the systemic toxicity of docetaxel, in this study, docetaxel-loaded albumin nanoparticles were fabricated by a novel simple self-assembly method. The resulting nanoparticles showed a mean diameter size of 150 nm. After being encapsulated into nanoparticles, docetaxel displayed similar cytotoxicity to traditional injection. Since polysorbate 80 was not involved in nanoparticles, the hemolysis was completely eliminated. The maximal tolerance dose of nanoparticles was also increased, which allowed a higher dose to be safely intravenously injected and produced ideal antitumor effects. The 150 nm diameter also allowed the nanoparticles to accumulate in tumor tissue via the enhanced permeability and retention effect. The passive targeting ability further caused the higher antitumor effects of nanoparticles than that of traditional injection at the same dose (7.5 mg/kg). Therefore, docetaxel-loaded albumin nanoparticles fabricated by our strategy showed higher promise in their safety and effectiveness than the traditional docetaxel injection.

Replacing heme with paclitaxel to prepare drug-loaded globin nanoassembles for CD163 targeting

Protein-based nanoparticles hold great promises in both preclinical and clinical practices, such as oncology diagnosis and treatment, because of their high biocompatibility and biodegradability. However, the complicated preparation and lack of targeting specific cells or tissues may limit their further uses. To overcome these limitations, we developed a novel replacing method for preparing dual-functional protein nanocarrier, such that one function is capable of encapsulating small molecule into protein, whereas the other function is cable of recognizing CD163 receptor [hemoglobin (Hb) scavenger receptor]. In this study, Hb was chosen as the targeting drug carrier. First, the heme group in the Hb was removed and replaced by paclitaxel (PTX) to form nanoparticles (Gb-NPs-PTX). The resulted Gb-NPs-PTX showed spherical shape and their diameter could be controlled in the range of 120-160 nm by altering the ratio of PTX to Hb. The binding activity of Gb-NPs-PTX to CD163 was confirmed by cell uptake in CD163(+) Chinese hamster ovary cells. Results in vivo also showed a CD163-dependent tissue accumulation of Gb-NPs-PTX in mice. In summary, by using the novel replacing method, PTX could be easily encapsulated into Hb nanoparticles and the targeting effects of Hb could also be kept.

Curcumin-incorporated albumin nanoparticles and its tumor image

Albumin is an ideal carrier for hydrophobic drugs. This paper reports a facile route to develop human serum albumin (HSA)-curcumin (CCM) nanoparticles, in which β-mercaptoethanol (β-ME) acted as an inducer and CCM acted as a bridge. Fluorescence quenching and conformational changes in HSA-CCM nanoparticles occurred during assembly. Disulfide bonds and hydrophobic interactions may play a key role in assembly. HSA-CCM nanoparticles were about 130 nm in size, and the solubility of CCM increased by more than 500 times. The HSA-CCM nanoparticles could accumulate at the cytoplasm of tumor cells and target the tumor tissues. Therefore, HSA nanoparticles fabricated by β-ME denaturation are promising nanocarriers for hydrophobic substances from chemotherapy drugs to imaging probes.

Targeted photosensitizer nanoconjugates based on human serum albumin selectively kill tumor cells upon photo-irradiation

Small and non-toxic nanoconjugates RGD–HSA–Ce6 could provide targeted and effective photodynamic therapy of tumor cells.

Chemical robotics — chemotactic drug carriers

In this review we show and describe a concept of designing autonomously moving artificial cells (chemical robots) carrying drugs and having tactic behavior based on artificial chemotaxis. Such systems could help to provide new and more efficient drug delivery applications. Chemical robot can be constructed based on the self-organization — natural “bottom-up” way — of fatty acid or lipid molecules into ordered nano- or micrometer size objects that have the ability to move and respond to environmental stimuli. The idea of using tactic carriers in drug delivery applications can be justified by the fact that cancer sites in the living body have different physiological characters (lower pH and higher resting temperature) compared to normal cells. The proposed “bottom-up” design method for self-propelled objects at small scales for targeted drug delivery applications could realize the original designation of nanoscience proposed 50 years ago by Richard Feynman.

One-step photo synthesis of protein-drug nanoassemblies for drug delivery

Upon controlled UV illumination, disulfide bonds in bovine α-lactalbumin (BLA) are selectively broken, leading to self-assembly of the BLA and doxorubicin (DOX) molecules into nanoparticles via hydrophobic interactions and intermolecular disulfide bonds. Such protein-drug nanoparticles have synergistic anticancer activity in vitro and tumor-homing specificity in vivo, which are of great potential for systemic drug delivery in cancer therapy.

A novel self-assembly albumin nanocarrier for reducing doxorubicin-mediated cardiotoxicity

Doxorubicin is an antitumor drug commonly used against a wide spectrum of tumors. However, the clinical application of DOX is restricted by its cardiotoxicity. To reduce the cardiotoxicity, we develop an albumin-based nanocarrier via a new molecular switch method for DOX delivery. Spherically shaped DOX-loaded HSA nanoparticles (NPs-DOX) are prepared with a drug-loading capacity and particle size of 4.3% and 120.1 ± 26 nm, respectively. In vivo studies demonstrate that NPs-DOX is able to preferentially accumulate in tumor and show great tumor inhibition on H22 hepatocellular-carcinoma-bearing mice. As for the toxicity, compared with free DOX, the maximum tolerated dose of NPs-DOX is increased from 10 to over 30 mg/kg, indicating the reduced systematic toxicity. More importantly, the cardiotoxicity induced by NPs-DOX is also significantly reduced because both left ventricular ejection fraction and left ventricular fractional shortening are almost not changed and other cardiotoxicity markers such as serum creatine kinase-MB, lactate dehydrogenase, superoxide dismutase, and malonaldehyde are kept constant. The reduced cardiotoxicity of NPs-DOX is also confirmed by nonhistological changes in the heart tissue. Therefore, such albumin-based nanocarrier can be one of the most promising strategies for the delivery of DOX.

Entrapped doxorubicin nanoparticles for the treatment of metastatic anoikis-resistant cancer cells

Metastasized and chemoresistant secondary breast cancer treatment commonly shows very low efficacy. A new efficient treatment method is required to overcome the limitation against the secondary breast cancer. In this study, anoikis-resistant breast cancer cells, MDA-MB-231 and MCF-7 were developed as models of chemoresistant and metastatic breast cancer. Doxorubicin encapsulating human serum albumin nanoparticles (HSA+DOX NPs) were fabricated to confirm the benefits of nanoparticles at the treatment of anoikis-resistant breast cancer cells. The side population (SP) fraction in the anoikis-resistant cancer cells was higher than the parental cells. HSA+DOX NPs were more cytotoxic to anoikis-resistant cancer cells than free doxorubicin. The confocal microscope images demonstrated HSA+DOX NPs to deliver more doxorubicin into cells compared to the free doxorubicin by bypassing the drug efflux pump systems of anoikis-resistant cancer cells. In this study, a nanomedicine-based drug delivery carrier shows a potential in treating a metastasized and chemoresistant breast cancer.

Molecular switch for the assembly of lipophilic drug incorporated plasma protein nanoparticles and in vivo image

A strategy to manipulate the disulfide bond breaking triggered unfolding, and subsequently assembly of human serum albumin (HSA) in a lipophilic drug-dependent manner is present. In this study, the hydrophobic region, a molecular switch of the HSA, was regulated to form HSA-paclitaxel (HSA-PTX) nanoparticles by a facile route. High-resolution transmission electron microscopy and fluorescence quenching indicate that HSA coassembled with PTX, which acts as a bridge to form core-shell nanoparticles about 50-240 nm in size, and that PTX might bind to the subdomain IIA sites of HSA. Change of ultraviolet absorption and circular dichroism spectra reveal the formation of HSA-PTX nanoparticles, which is a safety, injectable pharmaceutic nanocarrier system for tumor target. This method to prepare nanocarrier systems for hydrophobic guest molecules reveals a general principle of self-assembly for other plasma proteins and other pharmacologically active substances with poor water solubility. It also provides a basis for developing nanocarrier systems for a wide range of applications in nanomedicine, from drug delivery to bioimaging systems.