Synergistic chemotherapeutic effect of sorafenib-loaded pullulan-Dox conjugate nanoparticles against murine breast carcinoma

Preparation and characterization of Sorafenib nano-emulsion: impact on pharmacokinetics and toxicity; an in vitro and in vivo study

Hepatocellular carcinoma (HCC) ranks as the third leading cause of cancer-related deaths worldwide. Current treatment strategies include surgical resection, liver transplantation, liver-directed therapy, and systemic therapy. Sorafenib (Sor) is the first systemic drug authorized by the US Food and Drug Administration (FDA) for HCC treatment. Nevertheless, the conventional oral administration of Sor presents several limitations: poor solubility, low bioavailability, drug resistance development, and off-target tissue accumulation, leading to numerous adverse effects. Nano-emulsion, a nano-delivery system, is a viable carrier for poorly water-soluble drugs. It aims to enhance drug bioavailability, target organ accumulation, and reduce off-target tissue exposure, thus improving therapeutic outcomes while minimizing side effects. This study formulated Sor nano-emulsion (Sor NanoEm) using the homogenization technique. The resultant nano-emulsion was characterized by particle size (121.75 ± 12 nm), polydispersity index (PDI; 0.310), zeta potential (-12.33 ± 1.34 mV), viscosity (34,776 ± 3276 CPs), and pH (4.38 ± 0.3). Transmission Electron Microscopy exhibited spherical nano-droplets with no aggregation signs indicating stability. Furthermore, the encapsulation of Sor within the nano-emulsion sustained its release, potentially reducing the frequency of therapeutic doses. Cytotoxicity assessments on the HepG2 cell line revealed that Sor NanoEm had a significantly (P < 0.05) more potent cytotoxic effect compared to Sor suspension. Subsequent tests highlighted superior pharmacokinetic parameters and reduced dosage requirements of Sor NanoEm in mice. It exhibited an enhanced safety profile, particularly in behavior, brain, and liver, compared to its suspended form. These findings underscore the enhanced pharmacological and toxicological attributes of Sor Nano-emulsion, suggesting its potential utility in HCC treatment.

Recent advances in pH/enzyme-responsive polysaccharide-small-molecule drug conjugates as nanotherapeutics

Now-a-days, the polysaccharides are extensively employed for the delivery of small-molecule drugs ascribed to their excellent biocompatibility, biodegradability and modifiability. An array of drug molecules is often chemically conjugated with different polysaccharides to augment their bio-performances. As compared to their therapeutic precursors, these conjugates could typically demonstrate an improved intrinsic solubility, stability, bioavailability and pharmacokinetic profiles of the drugs. In current years, various stimuli-responsive particularly pH and enzyme-sensitive linkers or pendants are also exploited to integrate the drug molecules into the polysaccharide backbone. The resulting conjugates could experience a rapid molecular conformational change upon exposure to the microenvironmental pH and enzyme changes of the diseased states, triggering the release of the bioactive cargos at the targeted sites and eventually minimize the systemic side effects. Herein, the recent advances in pH and enzyme -responsive polysaccharide-drug conjugates and their therapeutic benefits are systematically reviewed, following a brief description on the conjugation chemistry of the polysaccharides and drug molecules. The challenges and future perspectives of these conjugates are also precisely discussed.

Biopolymeric Prodrug Systems as Potential Antineoplastic Therapy

Nowadays, cancer represents a major public health issue, a substantial economic issue, and a burden for society. Limited by numerous disadvantages, conventional chemotherapy is being replaced by new strategies targeting tumor cells. In this context, therapies based on biopolymer prodrug systems represent a promising alternative for improving the pharmacokinetic and pharmacologic properties of drugs and reducing their toxicity. The polymer-directed enzyme prodrug therapy is based on tumor cell targeting and release of the drug using polymer–drug and polymer–enzyme conjugates. In addition, current trends are oriented towards natural sources. They are biocompatible, biodegradable, and represent a valuable and renewable source. Therefore, numerous antitumor molecules have been conjugated with natural polymers. The present manuscript highlights the latest research focused on polymer–drug conjugates containing natural polymers such as chitosan, hyaluronic acid, dextran, pullulan, silk fibroin, heparin, and polysaccharides from Auricularia auricula.

Oral sorafenib-loaded microemulsion for breast cancer: evidences from the in-vitro evaluations and pharmacokinetic studies

Sorafenib tosylate (SFB) is a multikinase inhibitor that inhibits tumour growth and proliferation for the management of breast cancer but is also associated with issues like toxicity and drug resistance. Also, being a biopharmaceutical class II (BCS II) drug, its oral bioavailability is the other challenge. Henceforth, this report intended to encapsulate SFB into a biocompatible carrier with biodegradable components, i.e., phospholipid. The microemulsion of the SFB was prepared and characterized for the surface charge, morphology, micromeritics and drug release studies. The cell viability assay was performed on 4T1 cell lines and inferred that the IC₅₀ value of sorafenib-loaded microemulsion (SFB-loaded ME) was enhanced compared to the naïve SFB at the concentrations of about 0.75 µM. More drug was available for the pharmacological response, as the protein binding was notably decreased, and the drug from the developed carriers was released in a controlled manner. Furthermore, the pharmacokinetic studies established that the developed nanocarrier was suitable for the oral administration of a drug by substantially enhancing the bioavailability of the drug to that of the free SFB. The results bring forth the preliminary evidence for the future scope of SFB as a successful therapeutic entity in its nano-form for effective and safer cancer chemotherapy via the oral route.

Nano-strategies as Oral Drug Delivery Platforms for Treatment of Cancer: Challenges and Future Perspectives

Oral drug administration is the oldest and widely used method for drug administration. The objectives behind developing an oral drug delivery for the treatment of cancer are to achieve low cost treatment by utilizing novel techniques to target cancer through gut-associated lymphoid tissue (GALT) and to enhance patient comfort and compliance through a hospital-free treatment leading to "Chemotherapy at Home." Unfortunately, due to the physiological environment of the GIT and physicochemical properties of drug candidate, the efficacy of oral drug delivery methods is limited in the treatment of cancer. Due to their low hydrophilicity, high P-gp efflux and restricted intestinal permeability most of the anti-cancer drugs fail to achieve oral bioavailability. The review focuses on the efforts, challenges, opportunities and studies conducted by scientists worldwide on the oral administration of anticancer medications via nanocarriers such as liposomes, SLNs and dendrimers, because of their potential to overcome the epithelial barrier associated with GALT, as well as the applications of different polymers in targeting the cancer. The oral delivery can set newer horizons in cancer therapy to make it more patient friendly.

Targeted Cancer Therapy via pH-Functionalized Nanoparticles: A Scoping Review of Methods and Outcomes

(1) Background: In recent years, several studies have described various and heterogenous methods to sensitize nanoparticles (NPs) to pH changes; therefore, in this current scoping review, we aimed to map current protocols for pH functionalization of NPs and analyze the outcomes of drug-loaded pH-functionalized NPs (pH-NPs) when delivered in vivo in tumoral tissue. (2) Methods: A systematic search of the PubMed database was performed for all published studies relating to in vivo models of anti-tumor drug delivery via pH-responsive NPs. Data on the type of NPs, the pH sensitization method, the in vivo model, the tumor cell line, the type and name of drug for targeted therapy, the type of in vivo imaging, and the method of delivery and outcomes were extracted in a separate database. (3) Results: One hundred and twenty eligible manuscripts were included. Interestingly, 45.8% of studies (n = 55) used polymers to construct nanoparticles, while others used other types, i.e., mesoporous silica (n = 15), metal (n = 8), lipids (n = 12), etc. The mean acidic pH value used in the current literature is 5.7. When exposed to in vitro acidic environment, without exception, pH-NPs released drugs inversely proportional to the pH value. pH-NPs showed an increase in tumor regression compared to controls, suggesting better targeted drug release. (4) Conclusions: pH-NPs were shown to improve drug delivery and enhance antitumoral effects in various experimental malignant cell lines.

Vascular Endothelial Growth Factor Receptors [VEGFR] as Target in Breast Cancer Treatment: Current Status in Preclinical and Clinical Studies and Future Directions

Breast cancer [BC] is one of the most common cancers among women, one of the leading causes of a considerable number of cancer-related death globally. Among all procedures leading to the formation of breast tumors, angiogenesis has an important role in cancer progression and outcomes. Therefore, various anti-angiogenic strategies have developed so far to enhance treatment's efficacy in different types of BC. Vascular endothelial growth factors [VEGFs] and their receptors are regarded as the most well-known regulators of neovascularization. VEGF binding to vascular endothelial growth factor receptors [VEGFRs] provides cell proliferation and vascular tissue formation by the subsequent tyrosine kinase pathway. VEGF/VEGFR axis displays an attractive target for anti-angiogenesis and anti-cancer drug design. This review aims to describe the existing literature regarding VEGFR inhibitors, focusing on BC treatment reported in the last two decades.

Active targeted Janus nanoparticles enable anti-angiogenic drug combining chemotherapy agent to prevent postoperative hepatocellular carcinoma recurrence

Surgery is one of the main effective strategies for the treatment of solid tumors, but high postoperative recurrence is also the main cause of death in current cancer therapy. The prevention of postoperative hepatocellular carcinoma (HCC) recurrence is a clinical problem that needs to be solved urgently. At present, there are still some problems to be solved, such as, how to achieve free drugs to target the site of surgical resection; develop a strategy for the simultaneous administration of multiple drugs to inhibit postoperative recurrence; and provide the appropriate animal model that mimics the process of postoperative HCC recurrence. In this study, we used a facile and reproducible method to successfully prepare amphiphilic Janus nanoparticles (JNPs). In order to improve targeting of the JNPs to residual HCC cells after surgery, we modified the side of gold nanorods (GNRs) with lactobionic acid (LA), thus creating LA-JNPs. This provided an active and targeted co-delivery system for hydrophilic and hydrophobic drugs in separate rooms, thus avoiding mutual effects. Next, we established two models to simulate postoperative HCC recurrence: a subcutaneous postoperative recurrence model based on patient-derived tumor xenograft (PDX) tissues and a postoperative recurrence model of orthotopic HCC. By applying these models, the enhanced permeability and retention effect (EPR) based tumor targeting and LA based active targeting can jointly promote the enrichment and uptake of JNPs at tumor site. LA-JNPs represented an efficient targeting system for the co-delivery of Sorafenib/Doxorubicin with an optimized anti-recurrence effect and significantly improved the survival of mice during treatment for postoperative recurrence.

A Study of Hydrophobically Modified Pullulan Nanoparticles with Different Hydrophobic Densities on the Effect of Anti-Colon Cancer Cell Efficiency

To discuss the effect of hydrophobic groups of a polymer on the structural properties and function of polymer nanoparticles (NPs), we grafted chenodeoxycholic acid (CDCA) with pullulan (PU) to form hydrophobically modified PU (PUC). Three PUC polymers, namely, PUC-1, PUC-2, and PUC-3, with different degrees of substitution were designed by changing the feed ratio of CDCA and PU. ¹H-NMR spectra showed that the PUC polymer was successfully synthesized, and the degrees of hydrophobic substitution for PUC-1, PUC-2, and PUC-3 were calculated to be 10.66%, 13.92%, and 16.94%, respectively. The PUC NPs were prepared by the dialysis method and were shown to be uniformly spherical by transmission electron microscopy (TEM). The average sizes were about (220±10) nm, (203±7) nm, and (163±6) nm under dynamic light scattering (DLS) for PUC-1 NPs, PUC-2 NPs, and PUC-3 NPs, respectively. Drug release experiments showed that the three PUC/DOX NPs exhibited good sustained release. At 48 h, the IC₅₀ of doxorubicin in inhibiting colon cancer HCT116 cells was 0.0904 μg/mL. A cell study showed that PUC-3/DOX NPs had the highest uptake efficiency by HCT116 cells with the most cytotoxicity and inhibited the migration of HCT116 cells with the highest efficiency. The structural properties and function of polymer NPs were closely related to the hydrophobic groups in the polymer, and NPs with higher hydrophobicity showed a smaller size, higher drug capacity, and greater cell efficiency.

Progress in Application of Nanotechnology in Sorafenib

Dysregulation of the tyrosine kinase signaling pathway is closely related to tumor development, and tyrosine kinase inhibitors are important targets for potential anticancer strategies. In particular, sorafenib, as a representative drug of multitarget tyrosine kinase inhibitors, has an important clinical status and is widely used for treating various solid tumors and diabetic complications. However, poor aqueous solubility of sorafenib, poor bioavailability of commonly used oral dose forms, poor accumulation at tumor sites, and severe off-target effects that tend to induce intolerable systemic side effects in patients have greatly reduced its therapeutic efficiency and limited its extensive clinical application. To improve the properties of sorafenib, increase the efficiency of clinical treatment, and overcome the increasingly prominent phenomenon of sorafenib resistance, multiple investigations have been conducted. Numerous studies have reported that the properties of nanomaterials, such as small particle size, large specific surface area, high surface activity and high adsorption capacity, make nanotechnology promising for the construction of ideal sorafenib nanodelivery systems to achieve timed and targeted delivery of sorafenib to tumors, prolong the blood circulation time of the drug, improve the utilization efficiency of the drug and reduce systemic toxic side effects. This review summarizes the progress of research applications in nanotechnology related to sorafenib, discusses the current problems, and expresses expectations for the prospect of clinical applications of sorafenib with improved performance.

CD44-targeted pH-responsive micelles for enhanced cellular internalization and intracellular on-demand release of doxorubicin

Poor cellular uptake and slow intracellular drug release remain the main barriers for the efficient application of micellar delivery system. Taking advantage of the overexpressed CD44 receptor and mild acidic microenvironment of tumour cells, CD44-targeted pH-responsive micelles based on the self-assembly of histidine-hyaluronic acid-dodecylamine (His-HA-DA) were prepared for the delivery of doxorubicin (DOX). These micelles exhibited pH-responsive behaviour with increased particle size, decreased encapsulation efficiency (EE%) of DOX and rapid release of DOX triggered by low pH. Compared with free DOX, DOX/HHD exhibited relatively high cellular uptake mainly via the CD44-mediated endocytosis. The on-demand intracellular release of DOX from DOX/HHD led to improved cytotoxicity. DOX/HHD also showed great penetration efficiency in 3D tumour spheres in vitro. Moreover, these micelles with suitable particle size gained excellent tumour-targeting effects, as well as improved anti-tumour effects and reduced side effects in vivo. In conclusion, these micelles with CD44 targeted and pH-responsive behaviours provide a promising strategy for the efficient delivery of anti-tumour drugs in vivo.

Current status and future directions of hepatocellular carcinoma-targeted nanoparticles and nanomedicine

INTRODUCTION

Hepatocellular carcinoma (HCC) is a major health problem worldwide. Conventional therapies covering either chemotherapy or combination therapy still have sub-optimal responses with significant adverse effects and toxicity. Moreover, tumor cells usually acquire resistance quickly for traditional approaches, limiting their use in HCC. Interest in nanomedicine due to minimal systemic toxicity and a high degree of target-specific drug-delivery have pulled the attention of health scientists in this area of therapeutics.

AREA COVERED

The review covers the incidence and epidemiology of HCC, proposed molecular drug targets, mechanistic approach and emergence of nanomedicines including nanoparticles, lipidic nanoparticles, vesicular-based nanocarrier, virus-like particles with momentous therapeutic aspects including biocompatibility, and toxicity of nanocarriers along with conclusions and future perspective, with an efficient approach to safely cross physiological barriers to reach the target site for treating liver cancer.

EXPERT OPINION

Remarkable outcomes have recently been observed for the therapeutic efficacy of nanocarriers with respect to a specific drug target against the treatment of HCC by existing under trial drugs.

Reversing P-Glycoprotein-Associated Multidrug Resistance of Breast Cancer by Targeted Acid-Cleavable Polysaccharide Nanoparticles with Lapatinib Sensitization

For reversing the treatment failure in P-glycoprotein (P-gp)-associated MDR (multidrug resistance) of breast cancer, a high dose of Lapatinib (Lap), a substrate of breast cancer-resistant protein, was encapsulated into safe and effective acid-cleavable polysaccharide-doxorubicin (Dox) conjugates to form targeted HPP-Dox/Lap nanoparticles with an optimal drug ratio and appropriate nanosize decorated with oligomeric hyaluronic acid (HA) for specially targeting overexpressed CD44 receptors of MCF-7/ADR. The markedly increased cellular uptake and the strongest synergetic cytotoxicity revealed the enhanced reversal efficiency of HPP-Dox/Lap nanoparticles with reversal multiples at 29.83. This was also verified by the enhanced penetrating capacity in multicellular tumor spheroids. The reinforced Dox retention and substantial down-regulation of P-gp expression implied the possible mechanism of MDR reversal. Furthermore, the efficient ex vivo accumulation and distribution of nanoparticles in the tumor site and the high tumor growth inhibition (93%) even at a lower dosage (1 mg/kg) as well as lung metastasis inhibition in vivo with negligible side effects revealed the overwhelming advantages of targeted polysaccharide nanoparticles and Lap-sensitizing effect against drug-resistant tumor. The development of an efficient and nontoxic-targeted polysaccharide delivery system for reversing MDR by synergistic therapy might provide a potential clinical application value.

Recent advances of sorafenib nanoformulations for cancer therapy: Smart nanosystem and combination therapy

Sorafenib, a molecular targeted multi-kinase inhibitor, has received considerable interests in recent years due to its significant profiles of efficacy in cancer therapy. However, poor pharmacokinetic properties such as limited water solubility, rapid elimination and metabolism lead to low bioavailability, restricting its further clinical application. Over the past decade, with substantial progress achieved in the development of nanotechnology, various types of smart sorafenib nanoformulations have been developed to improve the targetability as well as the bioavailability of sorafenib. In this review, we summarize various aspects from the preparation and characterization to the evaluation of antitumor efficacy of numerous stimuli-responsive sorafenib nanodelivery systems, particularly with emphasis on their mechanism of drug release and tumor microenvironment response. In addition, this review makes great effort to summarize the nanosystem-based combination therapy of sorafenib with other antitumor agents, which can provide detailed information for further synergistic cancer therapy. In the final section of this review, we also provide a detailed discussion of future challenges and prospects of designing and developing ideal sorafenib nanoformulations for clinical cancer therapy.

Self-Assembled Organic Nanomaterials for Drug Delivery, Bioimaging, and Cancer Therapy

Over the past few decades, tremendous progress has been made in the development of engineering nanomaterials, which opened new horizons in the field of diagnosis and treatment of various diseases. In particular, self-assembled organic nanomaterials with intriguing features including delicate structure tailoring, facile processability, low cost, and excellent biocompatibility have shown outstanding potential in biomedical applications because of the enhanced permeability and retention (EPR) effect and multifunctional properties. In this review, we briefly introduce distinctive merits of self-assembled organic nanomaterials for biomedical applications. The main focus will be placed on summarizing recent advances in self-assembled organic nanomedicine for drug delivery, bioimaging, and cancer phototherapy, followed by highlighting a critical perspective on further development of self-assembled organic nanomaterials for future clinical translation. We believe that the above themes will appeal to researchers from different fields, including material, chemical, and biological sciences, as well as pharmaceutics.

Acid-labile polysaccharide prodrug via lapatinib-sensitizing effect substantially prevented metastasis and postoperative recurrence of triple-negative breast cancer

Surgical resection and chemotherapy are routinely performed for triple-negative breast cancer (TNBC) because it is insensitive to endocrine therapy and molecular targeted therapy. Here, the optimal surface charge (-28 mV) and particle size (51 nm) enabled the acid-labile hyaluronic acid pullulan prodrug (HPP)-doxorubicin (Dox)/lapatinib (Lap) conjugate to circulate in the blood for a lengthy period of time and enhance the electron paramagnetic resonance effect, while the targeted molecule hyaluronic acid accelerated CD44 receptor-mediated 4T1 cell internalization. The inefficient anti-proliferation capability of Lap increased more than 10-fold after sensitization of Dox to metastatic 4T1 cells, while cellular uptake significantly increased, and cell viability dramatically decreased to nearly 20% of the free Dox group. Furthermore, HPP-Dox/Lap more effectively inhibited lateral mobility, vertical migration, and invasion ability of 4T1 cells. The ex vivo biodistribution of representative Dox indicated that Lap obviously facilitated the intratumoral infiltration and accumulation. The in vivo research revealed that there were overwhelming advantages in using HPP-Dox/Lap to inhibit tumor growth, progression, and lung metastasis even at a low dosage (1 mg kg-1), and it decreased postoperative recurrence and pulmonary metastatic nodules. Because of the excellent biosafety and visible therapeutic effect on the 4T1 metastasis and recurrence model, there is great potential value for HPP-Dox/Lap to be used to treat metastatic TNBC.

Nanotechnology-Based Biopolymeric Oral Delivery Platforms for Advanced Cancer Treatment

Routes of drug administration and their corresponding physiochemical characteristics play major roles in drug therapeutic efficiency and biological effects. Each route of delivery has favourable aspects and limitations. The oral route of delivery is the most convenient, widely accepted and safe route. However, the oral route of chemotherapeutics to date have displayed high gastric degradation, low aqueous solubility, poor formulation stability and minimum intestinal absorption. Thus, mainstream anti-cancer drugs in current formulations are not suitable as oral chemotherapeutic formulations. The use of biopolymers such as chitosan, gelatin, hyaluronic acid and polyglutamic acid, for the synthesis of oral delivery platforms, have potential to help overcome problems associated with oral delivery of chemotherapeutics. Biopolymers have favourable stimuli-responsive properties, and thus can be used to improve oral bioavailability of anti-cancer drugs. These biopolymeric formulations can protect gastric-sensitive drugs from pH degradation, target specific binding sites for targeted absorption and consequently control drug release. In this review, the use of various biopolymers as oral drug delivery systems for chemotherapeutics will be discussed.

Fabrication of Carboxylmethyl Chitosan Nanocarrier via Self-Assembly for Efficient Delivery of Phenylethyl Resorcinol in B16 Cells

Micro-molecular drugs have special advantages to cope with challenging diseases, however their structure, physical and chemical properties, stability, and pharmacodynamics have more requirements for the way they are delivered into the body. Carrier-based drug delivery systems can circumvent many limited factors of drug delivery and increase their bioavailability. In this context, stable drug nanocarriers of alkaline amino acids (arginine, Arg) modified conjugated linoleic acid-carboxymethyl chitosan (CLA-CMCS) conjugate were developed, which could generate supramolecular micelles to effectively encapsulate the tyrosinase inhibitor phenylethyl resorcinol (PR). The resulting CCA-NPs were spherical nanoparticles with a mean size around 175 nm. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and cellular uptake investigation demonstrated that the CCA-NPs were non-cytotoxic and had excellent cell transport ability. In addition, these CCA-NPs were able to effectively deliver PR and inhibited melanin formation to reduce pigmentation by enhancing cellular uptake. In conclusion, our research indicated that nanocarriers based on self-assembly amphiphilic polymers constituted a promising and effective drug delivery system in hyperpigmentation targeting.

Transferrin-Modified Nanoliposome Codelivery Strategies for Enhancing the Cancer Therapy

Chemotherapy remains one of the most effective treatments for many cancers in a clinic. At present, various targets have been used to modify the PEGylated liposomes for doxorubicin (Dox) delivery, but the antitumor effect of Dox is not satisfactory. Therefore, combination chemotherapeutics has been considered as a promising method to improve tumor treatment. These years, RAF/MEK/ERK-mediated cell signaling pathway has been discovered to inhibit the growth of tumors. Thus, Sorafenib tosylate (Sor) was used in this study, which directly inhibited tumor cell proliferation through blocking RAF/MEK/ERK-mediated cell signaling pathway and indirectly inhibited tumor cell growth through blocking angiogenesis by VEGFR and PDGF. In this article, we develop a "combination delivery system" to deliver the hydrophobic drug (Sor) in phospholipid bilayer and hydrophilic drug (Dox) in inner cores for enhancing the antitumor effect. Moreover, in vitro experiments verified whether the physicochemical properties of carriers were stable and transferrin-modified liposomes displayed the highest uptake. The results of in vivo experiments showed that the codelivery system inhibited the tumor growth more effectively than monotherapy. Overall, this combination delivery system for delivering the hydrophobic and hydrophilic drugs simultaneously may offer a novel strategy for breast cancer treatment and provide a reference for the possibility of clinical usage.

Enzyme-Catalytic Self-Triggered Release of Drugs from a Nanosystem for Efficient Delivery to Nuclei of Tumor Cells

Stimulus-responsive drug delivery nanosystems (DDSs) are of great significance in improving cancer therapy for intelligent control over drug release. However, among them, many DDSs are unable to realize rapid and sufficient drug release because most internal stimulants might be consumed during the release process. To address the plight, an abundant supply of stimulants is highly desirable. Herein, a core crosslinked pullulan-di-(4,1-hydroxybenzylene)diselenide nanosystem, which could generate abundant exogenous-stimulant reactive oxygen species (ROS) via tumor-specific NAD(P)H:quinone oxidoreductase-1 (NQO1) catalysis, was constructed by the encapsulation of β-lapachone. The enzyme-catalytic-generated ROS induced self-triggered cascade amplification release of loaded doxorubicin (DOX) in the tumor cells, thus achieving efficient delivery of DOX to the nuclei of tumor cells by breaking the diselenide bond of the nanosystem. As a result, the antitumor effect of this nanosystem was significantly improved in the HepG2 xenograft model. In general, this study offers a new paradigm for utilizing the interaction between the loaded agent and carrier in the tumor cells to obtain self-triggered drug release in the design of DDSs for enhanced cancer therapy.

pH Responsiveness of Hexosomes and Cubosomes for Combined Delivery of Brucea javanica Oil and Doxorubicin

We report pH-responsive liquid crystalline lipid nanoparticles, which are dual-loaded by Brucea javanica oil (BJO) and doxorubicin hydrochloride (DOX) and display a pH-induced inverted hexagonal (pH = 7.4) to cubic (pH = 6.8) to emulsified microemulsion (pH = 5.3) phase transition with a therapeutic application in cancer inhibition. BJO is a traditional herbal medicine that strongly inhibits the proliferation and metastasis of various cancers. Doxorubicin is an antitumor drug, which prevents DNA replication and hampers protein synthesis through intercalation between the base pairs of the DNA helices. Its dose-dependent cardiotoxicity imposes the need for safe delivery carriers. Here, pH-induced changes in the structural and interfacial properties of designed multicomponent drug delivery (monoolein-oleic acid-BJO-DOX) systems are determined by synchrotron small-angle X-ray scattering and the Langmuir film balance technique. The nanocarrier assemblies display good physical stability in the studied pH range and adequate particle sizes and ζ-potentials. Their interaction with model lipid membrane interfaces is enhanced under acidic pH conditions, which mimic the microenvironment around tumor cells. In vitro cytotoxicity and apoptosis studies with BJO-DOX dual-loaded pH-switchable liquid crystalline nanoparticles are performed on the human breast cancer Michigan Cancer Foundation-7 (MCF-7) cell line and MCF-7 cells with doxorubicin resistance (MCF-7/DOX), respectively. The obtained pH-sensitive nanomedicines exhibit enhanced antitumor efficacy. The performed preliminary studies suggest a potential reversal of the resistance of the MCF-7/DOX cells to DOX. These results highlight the necessity for further understanding the link between the established pH-dependent drug release profiles of the nanocarriers and the role of their pH-switchable inverted hexagonal, bicontinuous cubic, and emulsified microemulsion inner organizations for therapeutic outcomes.

Design And Characterisation Of Novel Sorafenib-Loaded Carbon Nanotubes With Distinct Tumour-Suppressive Activity In Hepatocellular Carcinoma

PURPOSE

Over the past 30 years, no consistent survival benefits have been recorded for anticancer agents of advanced hepatocellular carcinoma (HCC), except for the multikinase inhibitor sorafenib (Nexavar®), which clinically achieves only ~3 months overall survival benefit. This modest benefit is attributed to limited aqueous solubility, slow dissolution rate and, consequently, limited absorption from the gastrointestinal tract. Thus, novel formulation modalities are in demand to improve the bioavailability of the drug to attack HCC in a more efficient manner. In the current study, we aimed to design a novel sorafenib-loaded carbon nanotubes (CNTs) formula that is able to improve the therapeutic efficacy of carried cargo against HCC and subsequently investigate the antitumour activity of this formula.

MATERIALS AND METHODS

Sorafenib was loaded on functionalized CNTs through physical adsorption, and an alginate-based method was subsequently applied to microcapsulate the drug-loaded CNTs (CNTs-SFN). The therapeutic efficacy of the new formula was estimated and compared to that of conventional sorafenib, both in vitro (against HepG2 cells) and in vivo (in a DENA-induced HCC rat model).

RESULTS

The in vitro MTT anti-proliferative assay revealed that the drug-loaded CNTs formula was at least two-fold more cytotoxic towards HepG2 cells than was sorafenib itself. Moreover, the in vivo animal experiments proved that our innovative formula was superior to conventional sorafenib at all assessed end points. Circulating AFP-L3% was significantly decreased in the CNTs-SFN-MCs-treated group (14.0%) in comparison to that of the DENA (40.3%) and sorafenib (38.8%) groups. This superiority was further confirmed by Western blot analysis and immunofluorescence assessment of some HCC-relevant biomarkers.

CONCLUSION

Our results firmly suggest the distinctive cancer-suppressive nature of CNTs-SFN-MCs, both against HepG2 cells in vitro and in a DENA-induced HCC rat model in vivo, with a preferential superiority over conventional sorafenib.

Synergistically Enhanced Inhibitory Effects of Pullulan Nanoparticle-Mediated Co-Delivery of Lovastatin and Doxorubicin to Triple-Negative Breast Cancer Cells

Triple-negative breast cancer (TNBC) is a subtype of breast cancer that is prone to drug resistance and difficult to treat. In this study, we grafted water-soluble pullulan with lovastatin (LV) to develop a novel amphiphilic conjugate, pullulan-encapsulated LV (PLV). The PLV conjugate was synthesized with three different ratios of pullulan to LV and characterized by Fourier transform infrared (FTIR). The degree of substitution (DS) of LV in terms of molar ratio was 7.87%, 3.58%, and 3.06% for PLV (1/2), PLV (1/3), and PLV (1/4), respectively, by proton NMR analysis. We selected the PLV (1/2) conjugate to prepare doxorubicin (DXR)-loaded PLV nanoparticles (PLV/DXR NPs) because of its superior properties. The average size and zeta potential for PLV (1/2) NPs were 177.6 nm and - 11.66 mV, respectively, determined by dynamic light scattering, and those for PLV/DXR NPs were 225.6 nm and - 10.51 mV, respectively. In vitro drug release profiling showed that PLV/DXR NPs sustainably released DXR within 72 h, which was more robust at pH 5.4 (97.90%) than pH 7.4 (76.15%). In the cytotoxicity study, PLV/DXR NPs showed greater inhibition of proliferation of TNBC MDA-MB-231 than non-TNBC MDA-MB-453 cells (IC₅₀ 0.60 vs 11.05 μM). FITC-loaded PLV/DXR NPs were prepared to investigate cellular uptake: both cell lines showed a time-dependent uptake of NPs, but the number of NPs entering MDA-MB-231 cells was greater than that entering the MDA-MB-453 cells. Pullulan-based NP co-delivery of LV and DXR could efficiently inhibit TNBC cells, which may help in designing a powerful drug delivery system for treating TNBC.

Polymeric nanoparticles as carrier for targeted and controlled delivery of anticancer agents

In recent decades, many novel methods by using nanoparticles (NPs) have been investigated for diagnosis, drug delivery and treatment of cancer. Accordingly, the potential of NPs as carriers is very significant for the delivery of anticancer drugs, because cancer treatment with NPs has led to the improvement of some of the drug delivery limitations such as low blood circulation time and bioavailability, lack of water solubility, drug adverse effect. In addition, the NPs protect drugs against enzymatic degradation and can lead to the targeted and/or controlled release of the drug. The present review focuses on the potential of NPs that can help the targeted and/or controlled delivery of anticancer agents for cancer therapy.

Co-delivery of sorafenib and metapristone encapsulated by CXCR4-targeted PLGA-PEG nanoparticles overcomes hepatocellular carcinoma resistance to sorafenib

Background

Sorafenib is approved as a standard therapy for advanced hepatocellular carcinoma (HCC), but its clinical application is limited due to moderate therapeutic efficacy and high incidence of acquired resistance resulted from elevated levels of SDF-1/CXCR4 axis induced by prolonged sorafenib treatment. We previously demonstrated metapristone (RU486 metabolite) as a cancer metastatic chemopreventive agent targeting SDF-1/CXCR4 axis. Therefore, we hypothesized that combining sorafenib with metapristone could synergistically suppress cell proliferation, enhance anti-cancer activity and repress potential drug resistance.

Methods

Changes in cellular CXCR4 expression by metapristone were analyzed by RT-PCR and western blotting. Effect of combining sorafenib with metapristone on cell viability was examined by MTT assay; combination index value was calculated to evaluate the synergistic effect of combined therapy. To overcome poor pharmacokinetics and reduce off-target toxicity, CXCR4-targeted nanoparticles (NPs) were developed to co-deliver sorafenib and metapristone into CXCR4-expressing HCC in vitro and in vivo; cell proliferation, colony formation and apoptosis assays were conducted; nude mice bearing HCC xenograft were used to examine effects of this therapeutic approach on HCC progression.

Results

Here we showed metapristone significantly reduced CXCR4 expression in HCC. Combinatory chemotherapy of sorafenib with metapristone synergistically suppressed HCC proliferation and resistance. CXCR4-targeted PEGylated poly (lactic-co-glycolic acid) NPs conjugated with LFC131 (a peptide inhibitor of CXCR4), could deliver more sorafenib and metapristone into HCC via specific recognition and binding with transmembrane CXCR4, and resulted in the enhanced cytotoxicity, colony inhibition and apoptosis by regulating more Akt/ERK/p38 MAPK/caspase signaling pathways. Co-delivery of sorafenib with metapristone by the LFC131-conjugated NPs showed prolonged circulation and target accumulation at tumor sites, and thus suppressed tumor growth in a tumor xenograft model.

Conclusions

In conclusion, co-delivery of sorafenib and metapristone via the CXCR4-targeted NPs displays a synergistic therapy against HCC. Our results suggest combinational treatment of chemotherapeutics offer an effective strategy for enhancing the therapeutic efficacy on carcinoma, and highlight the potential application of ligand-modified tumor-targeting nanocarriers in delivering drugs as a promising cancer therapeutic approach.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1216-x) contains supplementary material, which is available to authorized users.

Doxorubicin‑loaded dual‑functional hyaluronic acid nanoparticles: Preparation, characterization and antitumor efficacy in vitro and in vivo

A novel GHH copolymer was synthesized using hyaluronic acid modified with glycyrrhetinic acid and L-histidine (His), and doxorubicin-loaded GHH nanoparticles (DOX/GHH) were prepared for liver-targeted drug delivery and pH-responsive drug release. In the present study, GHH nanoparticles were characterized, and their pH-responsive behaviors were evaluated at different pH levels. The antitumor effect of the DOX/GHH nanoparticles was investigated in vitro and in vivo. Results showed that the DOX/GHH nanoparticles were spherical, and the particle sizes ranged from 238.1 to 156.7 nm with an increase in the degree of substitution of His. The GHH nanoparticles were obviously internalized into human hepatoblastoma cells. In vitro cytotoxicity assay results showed that the DOX/GHH nanoparticles exhibited a dose-dependent antitumor effect. Compared with free DOX, the DOX/GHH nanoparticles displayed higher antitumor efficacy. These results indicate that GHH nanoparticles could be a promising nano-delivery carrier of hydrophobic drugs for liver-targeted therapy.

Low-density lipoprotein decorated silica nanoparticles co-delivering sorafenib and doxorubicin for effective treatment of hepatocellular carcinoma

Combinational therapy is usually considered as a preferable approach for effective cancer therapy. Especially, combinational chemotherapies targeting different molecular targets are of particular interest due to its high flexibility as well as efficiency. In our study, the surface of silica nanoparticles (SLN) was modified with low-density lipoprotein (LDL) to construct platform (LDL-SLN) capable of specifically targeting low-density lipoprotein receptors (LDLRs) that overexpressing in hepatocellular carcinoma (HCC). In addition, the versatile drug loading capacity of LDL-SLN was employed to fabricate a preferable drug delivery system to co-deliver sorafenib (Sor) and doxorubicin (Dox) for combinational chemotherapy of HCC. Our results revealed that the LDL-SLN/Sor/Dox nanoparticles with size around 100 nm showed preferable stability in physiological environments. Moreover, the LDL-SLN/Sor/Dox could target LDLR overexpressed HepG2 cells. More importantly, both in vitro and in vivo experiments demonstrated that the LDL-SLN/Sor/Dox exerted elevated antitumor efficacy compared to Sor or Dox alone, which indicated that LDL-SLN/Sor/Dox could be a powerful tool for effective combinational chemotherapy of HCC.

Cancer Nanomedicines Stabilized by π-π Stacking between Heterodimeric Prodrugs Enable Exceptionally High Drug Loading Capacity and Safer Delivery of Drug Combinations

Combination therapy using distinct mode-of-action drugs has sparked a rapidly growing interest because this paradigm holds promise for improving the therapeutic efficacy of anticancer therapy. However, the current drug combination therapy refers to administering individual drugs together, which is far from a perfect regimen for cancer patients. The aim of this work was to demonstrate that synergistic delivery of two chemotherapeutic drugs in a single nanoparticle reservoir could be achieved through the rational chemical ligation of the drugs followed by supramolecular nano-assembly via blending of the drugs with a minimal amount of matrix. Choosing 7-ethyl-10-hydroxycamptothecin and taxanes, which are rich in aromatic structures, as model compounds, we show that the heterodimeric conjugates of the two agents are miscible with lipids to form systemically injectable nanomedicines. The compatibility between the prodrug conjugates and lipid carriers is substantially augmented by the intermolecular π-π stacking and alleviated polarity, thus enabling an exceptionally high drug loading (DL) capacity (~92%) and a gratifyingly long drug retention time within the micellar core. We further observed superior therapeutic outcomes in a mouse tumor model without detecting accompanying systemic toxicity. This structure-based, self-assembled cancer nanomedicine increased the potency and drug tolerability in animals and thus offers a robust strategy for simultaneously formulating two or more drugs in single nanovehicles.

Localized multidrug co-delivery by injectable self-crosslinking hydrogel for synergistic combinational chemotherapy

The multidrug co-loaded injectable hydrogels against tumor showed superiority and potential application values.