A self-assembling nanomedicine of conjugated linoleic acid-paclitaxel conjugate (CLA-PTX) with higher drug loading and carrier-free characteristic

pH-responsive self-assembled nanoparticles for tumor-targeted drug delivery

Recent advances in the field of drug delivery have opened new avenues for the development of novel nanodrug delivery systems (NDDS) in cancer therapy. Self-assembled nanoparticles (SANPs) based on tumour microenvironment have great advantages in improving antitumor effect, and pH-responsive SANPs prepared by the combination of pH-responsive nanomaterials and self-assembly technology can effectively improve the efficacy and reduce the systemic toxicity of antitumor drugs. In this review, we describe the characteristics of self-assembly and its driving force, the mechanism of pH-responsive NDDS, and the nanomaterials for pH-responsive SANPs type. A series of pH-responsive SANPs for tumour-targeted drug delivery are discussed, with an emphasis on the relation between structural features and theranostic performance.

Integrating Traditional Machine Learning and Deep Learning for Precision Screening of Anticancer Peptides: A Novel Approach for Efficient Drug Discovery

The rapid and effective identification of anticancer peptides (ACPs) by computer technology provides a new perspective for cancer treatment. In the identification process of ACPs, accurate sequence encoding and effective classification models are crucial for predicting their biological activity. Traditional machine learning methods have been widely applied in sequence analysis, but deep learning provides a new approach to capture sequence complexity. In this study, a two-stage ACPs classification model was innovatively proposed. Three novel coding strategies were explored; two mainstream Natural Language Processing (NLP) models and 11 machine learning models were fused to identify ACPs, which significantly improved the prediction accuracy of ACPs. We analyzed the correlation between peptide chain amino acids and evaluated the relevant performance of the model by the ROC curve and t-SNE dimensionality reduction technique. The results indicated that the deep learning and machine learning fusion models of M3E-base and KNeighborsDist models, especially when considering the semantic information on amino acid sequences, achieved the highest average accuracy (AvgAcc) of 0.939, with an AUC value as high as 0.97. Then, in vitro cell experiments were used to verify that the two ACPs predicted by the model had antitumor efficacy. This study provides a convenient and effective method for screening ACPs. With further optimization and testing, these strategies have the potential to play an important role in drug discovery and design.

Linoleate-pazopanib conjugation as active pharmacological ingredient to abolish hepatocellular carcinoma growth

Small molecule compounds targeting multiple kinases involved in neoangiogenesis have shown survival benefits in patients with unresectable hepatocellular carcinoma (HCC). Nonetheless, despite the beneficial effects of multikinase inhibitors (MKIs), a lack of boosting adjuvant limits their objective response rate. Lipid conjugates have been used to improve delivery efficacy or pharmaceutical benefits for decades. However, the feasibility of utilizing lipid-drug conjugates (LDCs) in HCC regimens remains untested. In this study, oral feeding of linoleate-fluorescein isothiocyanate conjugates showed that the compound was well distributed in a spontaneous HCC mouse model. Therefore, a rationale design was developed for chemically synthesizing a linoleate-pazopanib conjugate (LAPC). The LAPC showed a significantly improved cytotoxicity compared to the parental drug pazopanib. Pazopanib's angiogenic suppressing signals were not observed in LAPC-treated HCC cells, potentially suggesting an altered mechanism of action (MOA). In an efficacy trial comparing placebo, oral pazopanib, and LAPC treatments in the hepatitis B virus transgene-related spontaneous HCC mouse model (HBVtg-HCC), the LAPC treatment demonstrated superior tumor ablating capacity in comparison to both placebo and pazopanib treatments, without any discernible systemic toxicity. The LAPC exposure is associated with an apoptosis marker (Terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL]) and an enhanced ferroptosis (glutathione peroxidase 4 [GPX4]) potential in HBVtg-HCC tumors. Therefore, the LAPC showed excellent HCC ablative efficacy with altered MOA. The molecular mechanisms of the LAPC and LDCs for HCC therapeutics are of great academic interest. Further comprehensive preclinical trials (e.g., chemical-manufacture-control, toxicity, distribution, and pharmacokinetics/pharmacodynamics) are expected.

Self-assembled nanoformulations of paclitaxel for enhanced cancer theranostics

Chemotherapy has occupied the critical position in cancer therapy, especially towards the post-operative, advanced, recurrent, and metastatic tumors. Paclitaxel (PTX)-based formulations have been widely used in clinical practice, while the therapeutic effect is far from satisfied due to off-target toxicity and drug resistance. The caseless multi-components make the preparation technology complicated and aggravate the concerns with the excipients-associated toxicity. The self-assembled PTX nanoparticles possess a high drug content and could incorporate various functional molecules for enhancing the therapeutic index. In this work, we summarize the self-assembly strategy for diverse nanodrugs of PTX. Then, the advancement of nanodrugs for tumor therapy, especially emphasis on mono-chemotherapy, combinational therapy, and theranostics, have been outlined. Finally, the challenges and potential improvements have been briefly spotlighted.

Mesoporous Silica Nanoparticles as a Gene Delivery Platform for Cancer Therapy

Cancer remains a major global health challenge. Traditional chemotherapy often results in side effects and drug resistance, necessitating the development of alternative treatment strategies such as gene therapy. Mesoporous silica nanoparticles (MSNs) offer many advantages as a gene delivery carrier, including high loading capacity, controlled drug release, and easy surface functionalization. MSNs are biodegradable and biocompatible, making them promising candidates for drug delivery applications. Recent studies demonstrating the use of MSNs for the delivery of therapeutic nucleic acids to cancer cells have been reviewed, along with their potential as a tool for cancer therapy. The major challenges and future interventions of MSNs as gene delivery carriers for cancer therapy are discussed.

Synthesis of Novel Conjugated Linoleic Acid (CLA)-Coated Superparamagnetic Iron Oxide Nanoparticles (SPIONs) for the Delivery of Paclitaxel with Enhanced In Vitro Anti-Proliferative Activity on A549 Lung Cancer Cells

The application of Superparamagnetic Iron Oxide Nanoparticles (SPIONs) as a nanomedicine for Non-Small Cell Lung Carcinoma (NSCLC) can provide effective delivery of anticancer drugs with minimal side-effects. SPIONs have the flexibility to be modified to achieve enhanced oading of hydrophobic anticancer drugs such as paclitaxel (PTX). The purpose of this study was to synthesize novel trans-10, cis-12 conjugated linoleic acid (CLA)-coated SPIONs loaded with PTX to enhance the anti-proliferative activity of PTX. CLA-coated PTX-SPIONs with a particle size and zeta potential of 96.5 ± 0.6 nm and −27.3 ± 1.9 mV, respectively, were synthesized. The superparamagnetism of the CLA-coated PTX-SPIONs was confirmed, with saturation magnetization of 60 emu/g and 29 Oe coercivity. CLA-coated PTX-SPIONs had a drug loading efficiency of 98.5% and demonstrated sustained site-specific in vitro release of PTX over 24 h (i.e., 94% at pH 6.8 mimicking the tumor microenvironment). Enhanced anti-proliferative activity was also observed with the CLA-coated PTX-SPIONs against a lung adenocarcinoma (A549) cell line after 72 h, with a recorded cell viability of 17.1%. The CLA-coated PTX-SPIONs demonstrated enhanced suppression of A549 cell proliferation compared to pristine PTX, thus suggesting potential application of the nanomedicine as an effective site-specific delivery system for enhanced therapeutic activity in NSCLC therapy.

Enhanced photothermal heating and combination therapy of NIR dye via conversion to self-assembled ionic nanomaterials

Combination nanodrugs are promising therapeutic agents for cancer treatment. However, they often require the use of complex nanovehicles for transportation into the tumor site. Herein, a new class of carrier-free ionic nanomaterials (INMs) is presented, which are self-assembled by the drug molecules themselves. In this regard, a photothermal therapy (PTT) mechanism is combined with a chemotherapy (chemo) mechanism using ionic liquid chemistry to develop a combination drug to deliver multiple cytotoxic mechanisms simultaneously. Nanodrugs were developed from an ionic material-based chemo-PTT combination drug by using a simple reprecipitation method. Detailed examination of the photophysical properties (absorption, fluorescence emission, quantum yield, radiative and non-radiative rate) of the INMs revealed significant spectral changes which are directly related to their therapeutic effect. The reactive oxygen species quantum yield and the light to heat conversion efficiency of the photothermal agents were shown to be enhanced in combination nanomedicines as compared to their respective parent compounds. The ionic nanodrugs exhibited an improved dark and light cytotoxicity in vitro as compared to either the chemotherapeutic or photothermal parent compounds individually, due to a synergistic effect of the combined therapies, improved photophysical properties and their nanoparticles' morphology that enhanced the cellular uptake of the drugs. This study presents a general framework for the development of carrier-free dual-mechanism nanotherapeutics.

Carrier-free nanodrugs with efficient drug delivery and release for cancer therapy: From intrinsic physicochemical properties to external modification

The considerable development of carrier-free nanodrugs has been achieved due to their high drug-loading capability, simple preparation method, and offering "all-in-one" functional platform features. However, the native defects of carrier-free nanodrugs limit their delivery and release behavior throughout the in vivo journey, which significantly compromise the therapeutic efficacy and hinder their further development in cancer treatment. In this review, we summarized and discussed the recent strategies to enhance drug delivery and release of carrier-free nanodrugs for improved cancer therapy, including optimizing the intrinsic physicochemical properties and external modification. Finally, the corresponding challenges that carrier-free nanodrugs faced are discussed and the future perspectives for its application are presented. We hope this review will provide constructive information for the rational design of more effective carrier-free nanodrugs to advance therapeutic treatment.

Engineering of small-molecule lipidic prodrugs as novel nanomedicines for enhanced drug delivery

A widely established prodrug strategy can effectively optimize the unappealing properties of therapeutic agents in cancer treatment. Among them, lipidic prodrugs extremely uplift the physicochemical properties, site-specificity, and antitumor activities of therapeutic agents while reducing systemic toxicity. Although great perspectives have been summarized in the progress of prodrug-based nanoplatforms, no attention has been paid to emphasizing the rational design of small-molecule lipidic prodrugs (SLPs). With the aim of outlining the prospect of the SLPs approach, the review will first provide an overview of conjugation strategies that are amenable to SLPs fabrication. Then, the rational design of SLPs in response to the physiological barriers of chemotherapeutic agents is highlighted. Finally, their biomedical applications are also emphasized with special functions, followed by a brief introduction of the promising opportunities and potential challenges of SLPs-based drug delivery systems (DDSs) in clinical application.

Graphical Abstract

Pulmonary Delivery of Reactive Oxygen Species/Glutathione-Responsive Paclitaxel Dimeric Nanoparticles Improved Therapeutic Indices against Metastatic Lung Cancer

Chemotherapeutics often failed to elicit optimal antitumor responses against lung cancer due to their limited exposure and accumulation in tumors. To achieve an effective therapeutic outcome of paclitaxel (PTX) against metastatic lung cancer with attenuated systemic and local toxicities, pulmonary delivery of redox-responsive PTX dimeric nanoparticles (NPs) was introduced. PTX dimers conjugated through variable lengths of diacid linkers containing disulfide bonds (-SS-) (i.e., α-PTX-SS-PTX, β-PTX-SS-PTX, and γ-PTX-SS-PTX) were initially synthesized and were subsequently self-assembled into uniform nanosized particles in the presence of vitamin E TPGS with high drug loading capacity (DE > 97%). Among various redox-sensitive scaffolds, β-PTX-SS-PTX NPs exhibited an optimal reactive oxygen species/glutathione-responsive drug release behavior, causing a lower local toxicity profile of PTX in the lungs. The scaffolds also demonstrated excellent colloidal stability, cellular uptake efficiency, and discriminating cytotoxicity between cancer and healthy cells. Further, they depicted an improved lung retention as compared to the control nanovesicles (β-PTX-CC-PTX) devoid of the redox-sensitive disulfide motif. In the B16F10 melanoma metastatic lung cancer mouse model, intratracheally delivered β-PTX-SS-PTX NPs exhibited a stronger anticancer potential with reduced systemic toxicity as compared to Taxol intravenous injection containing an equivalent PTX dose. The PTX dimeric NPs could also dramatically reduce the local toxicity relative to Taxol following their pulmonary delivery. Thus, this study presents redox-responsive PTX dimeric NPs as a promising nanomedicine for improved therapeutic efficacy against metastatic lung cancer.

Antitumor Activity of α-Linolenic Acid-Paclitaxel Conjugate Nanoparticles: In vitro and in vivo

Purpose

Small molecule modified antitumor drug conjugate nanoparticles have the advantages of high drug loading, simple synthesis and preparation, and better biocompatibility. Due to the large demand for exogenous α-linolenic acid (ALA) by tumor cells, we synthesized α-linolenic acid-paclitaxel conjugate (ALA-PTX) and prepared α-linolenic acid-paclitaxel conjugate nanoparticles (ALA-PTX NPs), in order to obtain better tumor cellular uptake and antitumor activity in vitro and in vivo.

Methods

We synthesized and characterized ALA-PTX, and then prepared and characterized ALA-PTX NPs. The cellular uptake, uptake pathways, intracellular behavior, in vitro and in vivo antitumor activity of ALA-PTX NPs were evaluated.

Results

The size of ALA-PTX NPs was approximately 110.7±1.7 nm. The drug loading was approximately 90% (w/w) with CrEL-free and organic solvent-free characteristics. The cellular uptake of ALA-PTX NPs was significantly higher than that of PTX injection by MCF-7, MCF-7/ADR and HepG2 cells. In these three cell lines, the cellular uptake of ALA-PTX NPs at 6h was approximately 1.5-2.6 times higher than that of PTX injection. ALA-PTX NPs were ingested through clathrin-mediated endocytosis, then transferred to lysosomes, and could dissolve in cells to play an antitumor activity. The in vitro and in vivo antitumor activity of ALA-PTX NPs was confirmed in MCF-7/ADR and HepG2 cell models and tumor-bearing nude mouse models.

Conclusion

ALA-PTX NPs developed in our study could provide a new method for the preparation of nano-delivery systems suitable for antitumor therapy that could increase tumor cellular uptake and enhance antitumor activity.

Progress and Future Directions with Peptide-Drug Conjugates for Targeted Cancer Therapy

We review drug conjugates combining a tumor-selective moiety with a cytotoxic agent as cancer treatments. Currently, antibody-drug conjugates (ADCs) are the most common drug conjugates used clinically as cancer treatments. While providing both efficacy and favorable tolerability, ADCs have limitations due to their size and complexity. Peptides as tumor-targeting carriers in peptide-drug conjugates (PDCs) offer a number of benefits. Melphalan flufenamide (melflufen) is a highly lipophilic PDC that takes a novel approach by utilizing increased aminopeptidase activity to selectively increase the release and concentration of cytotoxic alkylating agents inside tumor cells. The only other PDC approved currently for clinical use is ¹⁷⁷Lu-dotatate, a targeted form of radiotherapy combining a somatostatin analog with a radionuclide. It is approved as a treatment for gastroenteropancreatic neuroendocrine tumors. Results with other PDCs combining synthetic analogs of natural peptide ligands with cytotoxic agents have been mixed. The field of drug conjugates as drug delivery systems for the treatment of cancer continues to advance with the application of new technologies. Melflufen provides a paradigm for rational PDC design, with a targeted mechanism of action and the potential for deepening responses to treatment, maintaining remissions, and eradicating therapy-resistant stem cells.

Self-Assembly Nanoparticles of Natural Bioactive Abietane Diterpenes

Different approaches have been reported to enhance penetration of small drugs through physiological barriers; among them is the self-assembly drug conjugates preparation that shows to be a promising approach to improve activity and penetration, as well as to reduce side effects. In recent years, the use of drug-conjugates, usually obtained by covalent coupling of a drug with biocompatible lipid moieties to form nanoparticles, has gained considerable attention. Natural products isolated from plants have been a successful source of potential drug leads with unique structural diversity. In the present work three molecules derived from natural products were employed as lead molecules for the synthesis of self-assembled nanoparticles. The first molecule is the cytotoxic royleanone 7α-acetoxy-6β-hydroxyroyleanone (Roy, 1) that has been isolated from hairy coleus (Plectranthus hadiensis (Forssk.) Schweinf). ex Sprenger leaves in a large amount. This royleanone, its hemisynthetic derivative 7α-acetoxy-6β-hydroxy-12-benzoyloxyroyleanone (12BzRoy, 2) and 6,7-dehydroroyleanone (DHR, 3), isolated from the essential oil of thicket coleus (P. madagascariensis (Pers.) Benth.) were employed in this study. The royleanones were conjugated with squalene (sq), oleic acid (OA), and/or 1-bromododecane (BD) self-assembly inducers. Roy-OA, DHR-sq, and 12BzRoy-sq conjugates were successfully synthesized and characterized. The cytotoxic effect of DHR-sq was previously assessed on three human cell lines: NCI-H460 (IC₅₀ 74.0 ± 2.2 µM), NCI-H460/R (IC₅₀ 147.3 ± 3.7 µM), and MRC-5 (IC₅₀ 127.3 ± 7.3 µM), and in this work Roy-OA NPs was assayed against Vero-E6 cells at different concentrations (0.05, 0.1, and 0.2 mg/mL). The cytotoxicity of DHR-sq NPs was lower when compared with DHR alone in these cell lines: NCI-H460 (IC₅₀ 10.3 ± 0.5 µM), NCI-H460/R (IC₅₀ 10.6 ± 0.4 µM), and MRC-5 (IC₅₀16.9 ± 0.5 µM). The same results were observed with Roy-OA NPs against Vero-E6 cells as was found to be less cytotoxic than Roy alone in all the concentrations tested. From the obtained DLS results, 12BzRoy-sq assemblies were not in the nano range, although Roy-OA NP assemblies show a promising size (509.33 nm), Pdl (0.249), zeta potential (−46.2 mV), and spherical morphology from SEM. In addition, these NPs had a low release of Roy at physiological pH 7.4 after 24 h. These results suggest the nano assemblies can act as prodrugs for the release of cytotoxic lead molecules.

Effect of XlogP and hansen solubility parameters on the prediction of small molecule modified docetaxel, doxorubicin and irinotecan conjugates forming stable nanoparticles

Small molecule-chemotherapeutic drug conjugate nanoparticles (SMCDC NPs) has a great advantage in improving drug loading. However, the factors which influence these conjugates forming stable nanoparticles (NPs) are currently unclear. In our previous studies, we synthesized a series of fatty acid-paclitaxel conjugates and suggested that the changes in the hydrophobic parameters (XlogP), solubility parameters and crystallinity of these fatty acid-paclitaxel conjugates were the key factors for affecting these small molecule-chemotherapeutic drug conjugates (SMCDCs) forming stable NPs in water. Here, we selected clinically widely used chemotherapeutic drug (docetaxel (DTX), doxorubicin (DOX) and irinotecan (Ir)) as model drug, and chose three straight-chain fatty acids (acetic acid (Ac), hexanoic acid (HA) and stearic acid (SA)) and one branched small molecule (N-(tert-butoxycarbonyl) glycine (B-G)) to synthesize 12 SMCDCs. Our results indicated that our prediction criterions obtained from paclitaxel conjugates were also appropriated for these synthesized SMCDCs. We suggested that the present studies expanded the scope of application of the above-mentioned influencing factors, provided research ideas for the rational design of SMCDC forming NPs and a basis for screening NPs with good anticancer activity.

A review on engineered magnetic nanoparticles in Non-Small-Cell lung carcinoma targeted therapy

There are growing appeals forthe design of efficacious treatment options for non-small-cell lung carcinoma (NSCLC) as it accrues to ~ 85% cases of lung cancer. Although platinum-based doublet chemotherapy has been the main therapeutic intervention in NSCLC management, this leads to myriad of problems including intolerability to the doublet regimens and detrimental side effects due to high doses. A new approach is therefore needed and warrants the design of targeted drug delivery systems that can halt tumor proliferation and metastasis by targeting key molecules, while exhibiting minimal side effects and toxicity. This review aims to explore the rational design of magnetic nanoparticles for the development of tumor-targeting systems for NSCLC. In the review, we explore the anticancer merits of conjugated linoleic acid (CLA) and provide a concise incursion into its application for the invention of functionalized magnetic nanoparticles in the targeted treatment of NSCLC. Recent nanoparticle-based targeted chemotherapies for targeting angiogenesis biomarkers in NSCLC will also be reviewed to further highlight versatility of magnetic nanoparticles. These developments through molecular tuning at the nanoscale and supported by comprehensive pre-clinical studies could lead to the establishment of precise nanosystems for tumor-homing cancer therapy.

Recent Advances in the Use of Lipid-Based Nanoparticles Against Glioblastoma Multiforme

Glioblastoma (GBM) is the most common and aggressive malignant brain tumor in adults. Although the overall incidence is less than 10 per 100,000 individuals, its poor prognosis and low survival rate make GBM a crucial public health issue. The main challenges for GBM treatment are related to tumor location and its complex and heterogeneous biology. In this sense, a broad range of nanoparticles with different sizes, architectures, and surface properties, have been engineered as brain drug delivery systems. Among them, lipid-based nanoparticles, such as liposomes, have been pointed out as promising materials to deliver antitumoral drugs to the central nervous system and thus, to improve brain drug targeting and therapeutic efficiency. Here, we describe the synthesis and general characteristics of lipid-based nanoparticles, as well as evidence in the past 5 years regarding their potential use to treat GBM.

Opportunities and challenges of fatty acid conjugated therapeutics

Instability, poor cellular uptake and unfavorable pharmacokinetics and biodistribution of many therapeutic molecules require modification in their physicochemical properties. The conjugation of these APIs with fatty acids has demonstrated an enhancement in their lipophilicity and stability. The improvement in the formulations that resulted from the conjugation of a drug with a fatty acid includes increased half-life, enhanced cellular uptake and retention, targeted tumor delivery, reduced chemoresistance in cancer, and improved blood-brain-barrier (BBB) penetration. In this review, various therapeutic molecules, including small molecules, peptides and oligonucleotides, that have been conjugated with fatty acid have been thoroughly discussed along with various conjugation strategies. The application of nano-system based delivery is gaining a lot of attention due to its ability to provide controlled drug release, targeting and reducing the extent of side effects. This review also covers various nano-carriers that have been utilized for the delivery of fatty acid drug conjugates. The enhanced lipophilicity of the drug-fatty acid conjugate has shown to enhance the affinity of the drug towards these carriers, thereby increasing the entrapment efficiency and formulation performance.

Advances and perspectives in carrier-free nanodrugs for cancer chemo-monotherapy and combination therapy

Nanocarrier-based drug delivery systems hold impressive promise for biomedical application because of their excellent water dispersibility, prolonged blood circulation time, increased drug accumulation in tumors, and potential in combination therapeutics. However, most nanocarriers suffer from low drug-loading efficiency, poor therapeutic effectiveness, potential systematic toxicity, and unstable metabolism. As an alternative, carrier-free nanodrugs, completely formulated with one or more drugs, have attracted increasing attention in cancer therapy due to their advantage of improved pharmacodynamics/pharmacokinetics, reduced toxicity, and high drug-loading. In recent years, carrier-free nanodrugs have contributed to progress in a variety of therapeutic modalities. In this review, different common strategies for carrier-free nanodrugs preparation are first summarized, mainly including nanoprecipitation, template-assisted nanoprecipitation, thin-film hydration, spray-drying technique, supercritical fluid (SCF) technique, and wet media milling. Then we describe the recently reported carrier-free nanodrugs for cancer chemo-monotherapy or combination therapy. The advantages of anti-cancer drugs combined with other chemotherapeutic, photosensitizers, photothermal, immunotherapeutic or gene drugs have been demonstrated. Finally, a future perspective is introduced to highlight the existing challenges and possible solutions toward clinical application of currently developed carrier-free nanodrugs, which may be instructive to the design of effective carrier-free regimens in the future.

Carrier-free nanodrugs for safe and effective cancer treatment

Clinical applications of many anti-cancer drugs are restricted due to their hydrophobic nature, requiring use of harmful organic solvents for administration, and poor selectivity and pharmacokinetics resulting in off-target toxicity and inefficient therapies. A wide variety of carrier-based nanoparticles have been developed to tackle these issues, but such strategies often fail to encapsulate drug efficiently and require significant amounts of inorganic and/or organic nanocarriers which may cause toxicity problems in the long term. Preparation of nano-formulations for the delivery of water insoluble drugs without using carriers is thus desired, requiring elegantly designed strategies for products with high quality, stability and performance. These strategies include simple self-assembly or involving chemical modifications via coupling drugs together or conjugating them with various functional molecules such as lipids, carbohydrates and photosensitizers. During nanodrugs synthesis, insertion of redox-responsive linkers and tumor targeting ligands endows them with additional characteristics like on-target delivery, and conjugation with immunotherapeutic reagents enhances immune response alongside therapeutic efficacy. This review aims to summarize the methods of making carrier-free nanodrugs from hydrophobic drug molecules, evaluating their performance, and discussing the advantages, challenges, and future development of these strategies.

Emerging insights on drug delivery by fatty acid mediated synthesis of lipophilic prodrugs as novel nanomedicines

Many drug molecules that are currently in the market suffer from short half-life, poor absorption, low specificity, rapid degradation, and resistance development. The design and development of lipophilic prodrugs can provide numerous benefits to overcome these challenges. Fatty acids (FAs), which are lipophilic biomolecules constituted of essential components of the living cells, carry out many necessary functions required for the development of efficient prodrugs. Chemical conjugation of FAs to drug molecules may change their pharmacodynamics/pharmacokinetics in vivo and even their toxicity profile. Well-designed FA-based prodrugs can also present other benefits, such as improved oral bioavailability, promoted tumor targeting efficiency, controlled drug release, and enhanced cellular penetration, leading to improved therapeutic efficacy. In this review, we discuss diverse drug molecules conjugated to various unsaturated FAs. Furthermore, various drug-FA conjugates loaded into various nanostructure delivery systems, including liposomes, solid lipid nanoparticles, emulsions, nano-assemblies, micelles, and polymeric nanoparticles, are reviewed. The present review aims to inspire readers to explore new avenues in prodrug design based on the various FAs with or without nanostructured delivery systems.

PEGylation of lipophilic SN38 prodrug with DSPE-mPEG2000 versus cremophor EL: comparative study for intravenous chemotherapy

The lipophilic prodrug of hydrophobic drugs with well-designed molecular structures can form stable pure prodrug nanoparticles (NPs), but rapid NPs aggregation in plasma greatly restricted their direct use for intravenous chemotherapy. To address this, DSPE-mPEG2000 and Cremophor EL are two of the most widely used lipophilic PEG derivatives to enhance their colloidal stability in plasma. However, their drug delivery performances have never been comparatively studied. Here, a redox-responsive lipophilic prodrug of SN38 was chosen as the model drug for such comparative investigations. We found that Cremophor EL/NPs having a small diameter (∼15 nm) and poor kinetic stability displayed an enhanced cell internalization, higher cytotoxicity and prolonged circulation time as compared with DSPE-mPEG2000/NPs. Most importantly, these superiorities further resulted in a much more potent antitumor activity in CT26 colorectal cancer xenograft, but the increased loss of body weight was also noted. These results suggested that Cremophor EL could be more advantageous than DSPE-mPEG2000 in terms of the improvement of antitumor activity, but the enhanced toxicity warranted further attention in the future study.

Production of conjugated fatty acids: A review of recent advances

Conjugated fatty acids (CFAs) have received a deal of attention due to the increasing understanding of their beneficial physiological effects, especially the anti-cancer effects and metabolism-regulation activities. However, the production of CFAs is generally difficult. Several challenges are the low CFAs content in natural sources, the difficulty to chemically synthesize target CFA isomers in high purity, and the sensitive characteristics of CFAs. In this article, the current technologies to produce CFAs, including physical, chemical, and biotechnical approaches were summarized, with a focus on the conjugated linoleic acids (CLAs) and conjugated linolenic acids (CLNAs) which are the most common investigated CFAs. CFAs usually demonstrate stronger physiological effects than other non-conjugated fatty acids; however, they are more sensitive to heat and oxidation. Consequently, the quality control throughout the entire production process of CFAs is significant. Special attention was given to the micro- or nano-encapsulation which presented as an emerging technique to improve the bioavailability and storage stability of CFAs. The current applications of CFAs and the potential research directions were also discussed.

Renal-clearable ultrasmall covalent organic framework nanodots as photodynamic agents for effective cancer therapy

Covalent organic frameworks (COFs) and their derivatives represent an emerging class of crystalline porous materials with broad potential applications. However, the biomedical applications of them were limited by the large size, low dispersivity, poor bioavailability within cells and metabolic problems. Herein, renal-clearable ultrasmall COF nanodots have been synthesized and utilized as efficient cancer therapy agents. A simple liquid exfoliation strategy was used to prepare COF nanodots. After polyethylene glycol (PEG) conjugation, the PEG coated COF nanodots (COF nanodots-PEG) showed improved physiological stability and biocompatibility. In addition, the well isolated porphyrin molecules endowed COF nanodots-PEG good light-triggered reactive oxygen species production ability, which showed excellent photodynamic therapy efficiency with good tumor accumulation ability. In particular, due to the ultrasmall size, COF nanodots-PEG could be cleared from the body through the renal filtration with no appreciable in vivo toxicity. Our study highlights the potential of COFs-based nanoparticles for biomedical applications.

Self-Assembled Indomethacin Dimer Nanoparticles Loaded with Doxorubicin for Combination Therapy in Resistant Breast Cancer

An ortho-ester-linked indomethacin (IND) dimer-based nanodrug delivery system was prepared to improve the therapeutic effect of doxorubicin (DOX) by reversing the multidrug resistance. The synthesized dimer (IND-OE) could form stable nanoparticles (IND-OE/DOX) loaded with DOX via the single-emulsion method. Compare to insensitive nanoparticles (IND-C12/DOX), IND-OE/DOX showed a rapid degradation behavior and accelerated drug release at mildly acidic environments. In vitro cell experiments verified that IND-OE nanoparticles could increase DOX concentration due to the efficient intracellular drug release by the degradation of the ortho ester as well as reduced DOX efflux by IND-mediated P-gp downregulation. In vivo studies further demonstrated that IND-OE/DOX displayed the maximized synergetic antitumor efficacy than free DOX or IND-C12/DOX, and the tumor inhibition rates versus saline were 46.78% (free DOX), 60.23% (IND-C12/DOX), and 80.62% (IND-OE/DOX). Overall, this strategy of combination with chemosensitizers and ortho ester linkage has great potential to serve as an amplifying chemotherapy platform against various drug-resistant tumors.

Efficient Click Synthesis of a Protonized and Reduction-Sensitive Amphiphilic Small-Molecule Prodrug Containing Camptothecin and Gemcitabine for a Drug Self-Delivery System

Drug self-delivery systems consisting of small-molecule active drugs with nanoscale features for intracellular delivery without the need for additional polymeric carriers have drawn much attention recently. In this work, we proposed a highly efficient strategy to fabricate protonized and reduction-responsive self-assembled drug nanoparticles from an amphiphilic small-molecule camptothecin-ss-1,2,3-triazole-gemcitabine conjugate (abbreviated as CPT-ss-triazole-GEM) for combination chemotherapy, which was prepared via a Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) "click" reaction. To obtain this drug-triazole-drug conjugate, we first prepared a CPT derivate containing a propargyl group linked with a disulfide group and a GEM derivate attached to an azide group. Subsequently, the two kinds of modified drugs were connected together through a CuAAC reaction between the alkynyl and azide groups to yield the CPT-ss-triazole-GEM prodrug. The characterizations of chemical structures of these intermediates and the final product were performed by ¹H NMR, Fourier transform infrared, and liquid chromatography/mass spectrometry measurements. This amphiphilic small-molecule drug-triazole-drug conjugate displayed a high drug loading content, that is, 36.0% of CPT and 27.2% of GEM. This kind of amphiphilic small-molecule prodrugs could form spherical nanoparticles in an aqueous solution in the absence of any other polymeric carriers, in which the hydrophobic CPT formed the core of the nanoparticles, whereas the hydrophilic GEM and protonated 1,2,3-triazole group yielded the shell. In the tumor microenvironment, the prodrug nanoparticles could release both pristine drugs simultaneously. Under the conditions of pH 7.4, and pH 7.4 and 2 μM glutathione (GSH), the prodrug nanoparticles could maintain stability and only 7% of CPT was leaked. However, in a high-GSH environment (pH 7.4 and 10 mM GSH) with the same incubation time, the disulfide linkage would be dissociated and lead to about 34% of CPT release. The results of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test demonstrated that these prodrug nanoparticles showed a higher cytotoxicity toward HepG2 cells than free CPT and free GEM on both 48 and 72 h of incubation. Both in vitro cellular uptake and flow cytometry results implied that these prodrug nanoparticles could be internalized by HepG2 cells with efficient drug release inside cells. The pharmacokinetics and tissue distribution of the prodrug showed a moderate half-life in vivo, and the prodrug peak concentration in most of the collected tissues appeared at 0.25 h after administration. In addition, the CPT-ss-triazole-GEM prodrug could not cross the blood-brain barrier. Even more important is the fact that there is no accumulation in tissues and a rapid elimination of this small-molecule prodrug could be achieved. In brief, this protonized and reduction-sensitive prodrug simultaneously binds both antitumor drugs and has good self-delivery behavior through the donor-acceptor interaction of the H-bonding ligand, that is, the 1,2,3-triazole group. It provides a new method for combined drug therapy.

Prodrugs in combination with nanocarriers as a strategy for promoting antitumoral efficiency

Prodrug entrapment into nanocarriers for tumor delivery is a strategy to achieve a valid therapy with high efficiency. The prodrug contains anticancer agents conjugating with functional moieties or ligands so that the active component is released after metabolism in the body or tumor. The advantages of nanosystems for loading prodrugs include high loading, increased prodrug stability, improved bioavailability and enhanced targeting to tumor cells. In the present article, we introduce the prodrug delivery approaches according to nanomedicine and the recent advances in prodrug-loaded nanocarriers. First, we discuss the conceptional design of combined prodrugs and nanocarriers in response to the obstruction in anticancer therapy. Then we describe the cases of prodrug-loaded nanoparticles for cancer treatment during the past 5 years.

Redox-sensitive prodrug nanoassemblies based on linoleic acid-modified docetaxel to resist breast cancers

Prodrug nanoassemblies, which can refrain from large excipients, achieve higher drug loading and control drug release, have been placed as the priority in drug delivery system. Reasoning that glutathione (GSH) and reactive oxygen species (ROS) are highly upgraded in tumor tissues which makes them attractive targets for drug delivery system, we designed and synthetized a novel prodrug which utilized mono thioether bond as a linker to bridge linoleic acid (LA) and docetaxel (DTX). This mono thioether-linked conjugates (DTX-S-LA) could self-assemble into nanoparticles without the aid of much excipients. The mono thioether endowed the nanoparticles redox sensitivity resulting in specific release at the tumor tissue. Our studies demonstrated that the nanoassemblies had uniform particle size, high stability and fast release behavior. DTX-S-LA nanoassemblies outperformed DTX solution in pharmacokinetic profiles for it had longer circulation time and higher area under curve (AUC). Compared with DTX solution, the redox dual-responsive nanoassemblies had comparable cytotoxic activity. Besides, the antitumor efficacy was evaluated in mice bearing 4T1 xenograft. It turned out this nanoassemblies could enhance anticancer efficacy by increasing the dose because of higher tolerance. Overall, these results indicated that the redox sensitivity nanoassemblies may have a great potential to cancer therapy.

Antitumor activity of the bioreductive prodrug 3-(2-nitrophenyl) propionic acid-paclitaxel nanoparticles (NPPA-PTX NPs) on MDA-MB-231 cells: in vitro and in vivo

Background

3-(2-Nitrophenyl) propionic acid-paclitaxel (NPPA-PTX) is a paclitaxel (PTX) bioreductive prodrug synthesized by our lab. We hypothesize that NPPA-PTX can self-assemble to form nanoparticles (NPs).

Materials and methods

In the present research, the theoretical partition coefficient (XlogP) and Hansen solubility parameters of NPPA-PTX were calculated. NPPA-PTX nanoparticles prepared by NPPA-PTX and DSPE-PEG (NPPA-PTX:DSPE-PEG =1:0.1, w/w) (NPPA-PTX@PEG NPs) were prepared and characterized. The cellular uptake, in vitro antitumor activity, in vivo targeting effect, tumor distribution, in vivo antitumor activity, and safety of NPPA-PTX@PEG NPs were investigated.

Results

Our results indicate that NPPA-PTX can self-assemble to form NPPA-PTX@PEG NPs. Both the cellular uptake and safety of NPPA-PTX@PEG NPs were higher than those of Taxol. NPPA-PTX@PEG NPs could target tumor tissues by a passive targeting effect. In tumor tissues, NPPA-PTX@PEG NPs could completely transform into active PTX. The in vivo antitumor activity of NPPA-PTX@PEG NPs was confirmed in MDA-MB-231 tumor-bearing nude mice.

Conclusion

The bioreductive prodrug NPPA-PTX could self-assemble to form NPs. The safety and antitumor activity of NPPA-PTX@PEG were confirmed in our in vitro and in vivo experiments. The NPPA-PTX@PEG NPs developed in this study could offer a new way of preparing bioreductive prodrug, self-assembled NPs suitable for antitumor therapy.

Anti-tumour activity of low molecular weight heparin doxorubicin nanoparticles for histone H1 high-expressive prostate cancer PC-3M cells

Nucleus-targeting drug delivery systems (NTDDs) deliver chemotherapeutic agents to nuclei in order to improve the efficacy of anti-tumour therapy. Histone H1 (H1) plays a key role in establishing and maintaining higher order chromatin structures and could bind to cell membranes. In the present study, we selected H1 as a target to prepare a novel H1-mediated NTDD. Low molecular weight heparin (LMHP) and doxorubicin (DOX) were combined to form LMHP-DOX. Then, a novel NTDD consisting of LMHP-DOX nanoparticles (LMHP-DOX NPs) was prepared by self-assembly. The characteristics of LMHP-DOX and LMHP-DOX NPs were investigated. Histone H1 high-expressive prostate cancer PC-3M cell line was selected as the cell model. Cellular uptake, and the in vitro and in vivo anti-tumour activity of LMHP-DOX NPs were evaluated on H1 high-expressive human prostate cancer PC-3M cells. Our results indicated that intact LMHP-DOX NPs mediated by H1 could be absorbed by H1 high-expressive PC-3M cells, escape from the lysosomes to the cytoplasm, and localize in the perinuclear region via H1-mediated, whereby DOX could directly enter the cell nucleus and quickly increase the concentration of DOX in the nuclei of H1 high-expressive PC-3M cells to enhance the apoptotic activity of cancer cells. The anti-coagulant activity of LMHP-DOX NPs was almost completely diminished in rat blood compared with that of LMHP, indicating the safety of LMHP-DOX NPs. Compared to traditional NTDD strategies, LMHP-DOX NPs avoid the complicated modification of nucleus-targeting ligands and provide a compelling solution for the substantially enhanced nuclear uptake of chemotherapeutic agents for the development of more intelligent NTDDs.

Carrier-free nanodrug by co-assembly of chemotherapeutic agent and photosensitizer for cancer imaging and chemo-photo combination therapy

Nanosized drug delivery systems (NDDS) with photothermal therapy (PTT) and photodynamic therapy (PDT) have been extensively exploited to improve the therapeutic performance and bio-safety of chemotherapeutic drugs in cancer. In this work, a carrier-free nanodrug was developed by co-assembly of the anti-cancer agent ursolic acid (UA), an asialoglycoprotein receptor (ASGPR), which can recognize the target molecule lactobionic acid (LA), and the near-infrared (NIR) probe dye indocyanine green (ICG) to form UA-LA-ICG NPs by a simple and green self-assembly approach. The UA-LA-ICG NPs had suitable stability, showed controlled release profile of UA drugs, and exhibited preferable temperature response (∼59.4 °C) under laser irradiation (808 nm, 1 W/cm2). Compared with free ICG, the UA-LA-ICG NPs significantly enhanced the intracellular ICG uptake. Upon irradiation of the NIR laser, co-assembled nanodrugs demonstrated great performance as a reactive oxygen species (ROS) producer and exhibited more anti-proliferative activities on ASGPR-overexpressing HepG2 cells than ASGPR low-expressing HeLa cells. Meanwhile, in vivo NIR fluorescence imaging exhibited that the co-assembled nanodrugs were specifically targeted to the tumor by the active targeting property of LA, and its circulation time was much longer than that of free ICG. In addition, UA-LA-ICG NPs + NIR irradiation treatment displayed enhanced inhibitory effect on tumor growth in H22 tumor-bearing mice. Overall, the co-assembly of chemotherapeutic agent and photosensitizer by the self-assembly approach might open an alternative avenue and give inspiration to fabricate new carrier-free nanodrugs for cancer imaging and chemo-photo combination therapy.

STATEMENT OF SIGNIFICANCE

The present study for the first time reported carrier-free nanoparticles (NPs) by co-assembly of a natural product ursolic acid (UA), an asialoglycoprotein receptor (ASGPR)-recognized sugar molecule lactobionic acid (LA), and the near-infrared dye indocyanine green (ICG) through a simple and green approach. The preparation process of nanodrugs is simple, rapid, effective, and labor-saving. The co-assembled nanodrugs were capable of stabilizing the ICG molecules and specifically targeting to the tumor, which could increase the tumor accumulation in cancer imaging and also enhance the efficacy of chemo-phototherapy.

The theranostic efficiency of tumor-specific, pH-responsive, peptide-modified, liposome-containing paclitaxel and superparamagnetic iron oxide nanoparticles

Background

In the present study, the tumor-specific, pH-responsive peptide H₇K(R₂)₂-modified, theranostic liposome-containing paclitaxel (PTX) and superparamagnetic iron oxide nanoparticles (SPIO NPs), PTX/SPIO-SSL-H₇K(R₂)₂, was prepared by using H₇K(R₂)₂ as the targeting ligand, SPIO NPs as the magnetic resonance imaging (MRI) agent, PTX as antitumor drug.

Methods

The PTX/SPIO-SSL-H₇K(R₂)₂ was prepared by a thin film hydration method. The characteristics of PTX/SPIO-SSL-H₇K(R₂)₂ were evaluated. The targeting effect, MRI, and antitumor activity of PTX/SPIO-SSL-H₇K(R₂)₂ were investigated detail in vitro and in vivo in human breast carcinoma MDA-MB-231 cell models.

Results

Our results of in vitro flow cytometry, in vivo imaging, and in vivo MR imaging confirmed the pH-responsive characteristic of H₇K(R₂)₂ in MDA-MB-231 cell line in vitro and in vivo. The results of in vivo MRI and in vivo antitumor activity confirmed the theranostic effect of PTX/SPIO-SSL-H₇K(R₂)₂ in MDA-MB-231 tumor-bearing model.

Conclusion

Considering all our in vitro and in vivo results, we conclude that we developed targeting modified theranostic liposome which could achieve both role of antitumor and MRI.

Advances in thermosensitive polymer-grafted platforms for biomedical applications

Studies on "smart" polymeric material performing environmental stimuli such as temperature, pH, magnetic field, enzyme and photo-sensation have recently paid much attention to practical applications. Among of them, thermo-responsive grafted copolymers, amphiphilic steroids as well as polyester molecules have been utilized in the fabrication of several multifunctional platforms. Indeed, they performed a strikingly functional improvement comparing to some original materials and exhibited a holistic approach for biomedical applications. In case of drug delivery systems (DDS), there has been some successful proof of thermal-responsive grafted platforms on clinical trials such as ThermoDox®, BIND-014, Cynviloq IG-001, Genexol-PM, etc. This review would detail the recent progress and highlights of some temperature-responsive polymer-grafted nanomaterials or hydrogels in the 'smart' DDS that covered from synthetic polymers to nature-driven biomaterials and novel generations of some amphiphilic functional platforms. These approaches could produce several types of smart biomaterials for human health care in future.

Effect of XlogP and Hansen Solubility Parameters on Small Molecule Modified Paclitaxel Anticancer Drug Conjugates Self-Assembled into Nanoparticles

Small molecule modified anticancer drug conjugates (SMMDCs) can self-assemble into nanoparticles (NPs) as therapeutic NP platforms for cancer treatment. Here we demonstrate that the XlogP and Hansen solubility parameters of paclitaxel (PTX) SMMDCs is essential for SMMDCs self-assembling into NPs. The amorphous state of PTX SMMDCs will also affect SMMDCs self-assembling into NPs. However, the antitumor activity of these PTX SMMDCs NPs decreased along with their XlogP values, indicating that a suitable XlogP value for designing the SMMDCs is important for self-assembling into NPs and for possessing antitumor activity. For higher level XlogP SMMDCs, a degradable linker should be considered in the design of SMMDCs to overcome the problem of lower antitumor activity. It is preferable that the hydrophilic groups in the SMMDCs should be present on the surface of self-assembling NPs.

Three-Dimensional Microphase Separation and Synergistic Permeability in Stacked Lipid-Polymer Hybrid Membranes

We present new structures of soft-material thin films that augment the functionality of substrate-mediated delivery systems. A hybrid material composed of phospholipids and block copolymers adopts a multilayered membrane structure supported on a solid surface. The hybrid films comprise intentional intramembrane heterogeneities that register across multilayers. These stacked domains convey unprecedented enhancement and control of permeability of solutes across micrometer-thick films. Using grazing incidence X-ray scattering, phase contrast atomic force microscopy, and confocal microscopy, we observed that in each lamella, lipid and polymers partition unevenly within the membrane plane segregating into lipid- or polymer-rich domains. Interestingly, we found evidence that like-domains align in registry across multilayers, thereby making phase separation three-dimensional. Phase boundaries exist over extended length scales to compensate the height mismatch between lipid and polymer molecules. We show that microphase separation in hybrid films can be exploited to augment the capability of drug-eluting substrates. Lipid-polymer hybrid films loaded with paclitaxel show synergistic permeability of drug compared to single-component counterparts. We present a thorough structural study of stacked lipid-polymer hybrid membranes and propose that the presence of registered domains and domain boundaries impart enhanced drug release functionality. This work offers new perspectives in designing thin films for controlled delivery applications.

Self-assembling prodrugs

Covalent modification of therapeutic compounds is a clinically proven strategy to devise prodrugs with enhanced treatment efficacies. This prodrug strategy relies on the modified drugs that possess advantageous pharmacokinetic properties and administration routes over their parent drug. Self-assembling prodrugs represent an emerging class of therapeutic agents capable of spontaneously associating into well-defined supramolecular nanostructures in aqueous solutions. The self-assembly of prodrugs expands the functional space of conventional prodrug design, affording a possible pathway to more effective therapies as the assembled nanostructure possesses distinct physicochemical properties and interaction potentials that can be tailored to specific administration routes and disease treatment. In this review, we will discuss the various types of self-assembling prodrugs in development, providing an overview of the methods used to control their structure and function and, ultimately, our perspective on their current and future potential.

Dual-Targeting Multifuntional Mesoporous Silica Nanocarrier for Codelivery of siRNA and Ursolic Acid to Folate Receptor Overexpressing Cancer Cells

A targeting drug delivery system (TDDS) can selectively deliver antitumor drugs to cancerous parts to improve its anticancer efficacy. Hence, a targeted drug delivery system (UA/siVEGF@MSN-FA) coloading ursolic acid (UA) and vascular endothelial growth factor (VEGF) targeted siRNA (siVEGF) based on mesoporous silica (MSN) nanocarrier modified by a folic acid (FA) molecule was designed and synthesized. The MSN-FA nanoparticles were investigated for shape, diameter, and zeta potential and and by infrared (IR) spectroscopy. FR-overexpressing HeLa cells and FR-negative HepG2 cell lines were used to evaluate the in vitro cellular uptake and the cytotoxicity of MSN-FA nanoparticles. The morphology of HeLa cells transfected with siVEGF@MSN-FA was observed using fluorescence microscopy. Our findings demonstrated that UA@MSN-FA nanoparticles were near-spherical, and the particle size was about 209 ± 9.21 nm. The MSN-FA nanocarrier not only could enhance the in vitro transfection efficiency and the stability of siVEGF but also could further improve the targeted anticancer efficacy of UA and siVEGF via the active targeting property of FA. Overall, the MSN-FA drug delivery system could serve as an excellent material in biomedical applications.

Self-assembly of glutamic acid linked paclitaxel dimers into nanoparticles for chemotherapy

In this work, a glutamic acid linked paclitaxel (PTX) dimer (Glu-PTX₂) with high PTX content of 88.9wt% was designed and synthesized. Glu-PTX₂ could self-assemble into nanoparticles (Glu-PTX₂ NPs) in aqueous solution to increase the water solubility of PTX. Glu-PTX₂ NPs were characterized by electron microscopy and dynamic light scattering, exhibiting spherical morphology and favorable structural stability in aqueous media. Glu-PTX₂ NPs could be internalized by cancer cells as revealed by confocal laser scanning microscopy and exert potent cytotoxicity. It is envisaged that Glu-PTX₂ NPs would be an alternative formulation for PTX, and such amino acid linked drug dimers could also be applied to other therapeutic agents.

Lymph cancer chemotherapy: delivery of doxorubicin-gemcitabine prodrug and vincristine by nanostructured lipid carriers

PURPOSE

Radiation and chemotherapy are the most common course of treatment for B-cell lymphoma. Doxorubicin (DOX), gemcitabine (GEM), and vincristine (VCR) are the commonly used antilymphoma chemotherapeutic drugs. The aim of this study is to construct a novel drug delivery system for the combination delivery of the three drugs on lymphoma.

MATERIALS AND METHODS

DOX-GEM prodrug was synthesized. Novel nanostructured lipid carriers (NLCs) containing DOX-GEM prodrug and VCR were prepared and used to treat B-cell lymphoma through in vivo treatment to a lymph cancer animal model. The systemic toxicity of the nanomedicine was also evaluated during the treatment.

RESULTS

DOX-GEM prodrug and VCR-loaded NLCs (DOX-GEM VCR NLCs) exhibited the highest antitumor effect in B-cell lymphoma cells and lymphoma animal xenografts when compared with the single drug-loaded NLCs and the drug solutions.

CONCLUSION

It could be concluded that the highest antitumor effect can be achieved by the system due to the stable drug-loading capacity, attractive anticancer therapeutic effects, and reduced toxicities in human Burkitt's lymphoma cell line and mice-bearing cancer model. The resulting DOX-GEM VCR NLCs could be an efficient antilymph cancer agent and could be developed further for the treatment of other tumors.

Glutathione-responsive paclitaxel dimer nanovesicles with high drug content

Paclitaxel dimers containing mono thioether linkers can self-assemble into hollow nanovesicles that exhibit comparable cytotoxicity to Taxol.

Nanoprodrug of retinoic acid-modified paclitaxel

A nanoprodrug with high content (75%) and increased water solubility of paclitaxel was prepared from retinoic acid-modified paclitaxel.