Synergistic effect of reduced polypeptide micelle for co-delivery of doxorubicin and TRAIL against drug-resistance in breast cancer

Lyotropic liquid crystalline 2D and 3D mesophases: Advanced materials for multifunctional anticancer nanosystems

Cancer remains a leading cause of mortality. Despite significant breakthroughs in conventional therapies, treatment is still far from ideal due to high toxicity in normal tissues and therapeutic inefficiency caused by short drug lifetime in the body and resistance mechanisms. Current research moves towards the development of multifunctional nanosystems for delivery of chemotherapeutic drugs, bioactives and/or radionuclides that can be combined with other therapeutic modalities, like gene therapy, or imaging to use in therapeutic screening and diagnosis. The preparation and characterization of Lyotropic Liquid Crystalline (LLC) mesophases self-assembled as 2D and 3D structures are addressed, with an emphasis on the unique properties of these nanoassemblies. A comprehensive review of LLC nanoassemblies is also presented, highlighting the most recent advances and their outstanding advantages as drug delivery systems, including tailoring strategies that can be used to overcome cancer challenges. Therapeutic agents loaded in LLC nanoassemblies offer qualitative and quantitative enhancements that are superior to conventional chemotherapy, particularly in terms of preferential accumulation at tumor sites and promoting enhanced cancer cell uptake, lowering tumor volume and weight, improving survival rates, and increasing the cytotoxicity of their loaded therapeutic agents. In terms of quantitative anticancer efficacy, loaded LLC nanoassemblies reduced the IC50 values from 1.4-fold against lung cancer cells to 125-fold against ovarian cancer cells.

Tumor Microenvironment Multiple Responsive Nanoparticles for Targeted Delivery of Doxorubicin and CpG Against Triple-Negative Breast Cancer

Introduction

Currently, the main treatment for advanced breast cancer is still chemotherapy. Immunological and chemical combination therapy has a coordinated therapeutic effect and achieves some efficacy. However, the immunosuppressive tumor microenvironment is a major cause for the failure of immunotherapy in breast cancer. CpG oligodeoxynucleotides can activate the tumor immune microenvironment to reverse the failure of immunotherapy.

Methods

In this study, we designed an amphiphilic peptide micelle system (Co-LMs), which can targeted delivery of the immune adjuvant CpG and the chemotherapeutic drug doxorubicin to breast cancer tumors simultaneously. The peptide micelle system achieved tumor microenvironment pH and redox-sensitive drug release.

Results and Discussion

Co-LMs showed 2.3 times the antitumor efficacy of chemotherapy alone and 5.1 times the antitumor efficacy of immunotherapy alone in triple-negative breast cancer mice. Co-LMs activated cytotoxic CD8+ T lymphocytes and CD4+ T cells in mice to a greater extent than single treatments. We also found that Co-LMs inhibited the metastasis of circulating tumor cells in the bloodstream to some extent. These results indicate that the Co-LMs offer a promising therapeutic strategy against triple-negative breast cancer.

Co-delivery Systems of Multiple Drugs Using Nanotechnology for Future Cancer Therapy

Cancer treatments have improved significantly during the last decade but are not yet satisfactory. Combination therapy is often administered to improve efficacy and safety. Drug delivery systems can also improve efficacy and safety. To control the spatiotemporal distribution of drugs, nanotechnology involving liposomes, solid lipid nanoparticles, and polymeric micelles has been developed. Co-delivery systems of multiple drugs are a promising approach to combat cancer. Synergistic effects and reduced side effects are expected from the use of co-delivery systems. In this review, we summarize various co-delivery systems for multiple drugs, including small-molecule drugs, nucleic acids, genes, and proteins. Co-delivery of drugs with different properties is relatively difficult, but some researchers have succeeded in developing such co-delivery systems. Environment-responsive carrier designs can control the release of cargos. Although their preparation is more complicated than that of mono-delivery systems, co-delivery systems can simplify clinical procedures and improve patient QOL.

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.

Co-delivery of doxorubicin and TRAIL plasmid by modified PAMAM dendrimer in colon cancer cells, in vitro and in vivo evaluation

One strategy for cancer treatment is combination therapy using nanoparticles (NPs), which has resulted in enhanced anti-cancer effects and reduced cytotoxicity of therapeutic agents. Polyamidoamine dendrimer (PAMAM) has attracted considerable attention because of its potential applications ranging from drug delivery to molecular encapsulation and gene therapy. In this study, PAMAM G5 modified with cholesteryl chloroformate and alkyl-PEG was applied for co-delivery of doxorubicin (DOX) and plasmid encoding TRAIL into colon cancer cells, in vitro and in vivo. The results showed DOX was efficiently encapsulated in modified carrier (M-PAMAM) with loading level about 90%, and the resulting DOX-loaded M-PAMAM complexed with TRAIL plasmid showed much stronger antitumor effect than M-PAMAM containing DOX or TRAIL plasmid. On the other hand, the obtained results demonstrated that the treatment of mice bearing C26 colon carcinoma with this developed co-delivery system significantly decreased tumor growth rate. Thus, this modified PAMAM G5 can be considered as a potential carrier for co-delivery of drug and gene in cancer therapy.

Chitosan-alginate BSA-gel-capsules for local chemotherapy against drug-resistant breast cancer

BACKGROUND AND OBJECT

Polyelectrolyte microcapsule is a promising candidate for multifunctional drug delivery system. However, the lack of reports about animal experiments have greatly slowed down their development for drug delivery. We engineered biodegradable chitosan-alginate polyelectrolyte multilayer capsule filled with bovine serum albumin gel (BSA-gel-capsule). Herein, we demonstrated their applicability for local chemotherapy, a means of treating local or regional malignancies by direct administration of anti-tumor agents to tumor sites.

METHOD

Doxorubicin (DOX) was loaded in BSA-gel-capsules and DOX-resistant cell line (MCF-7/ADR cells) was employed for antitumor studies in vitro. The cytotoxicity, cellular uptake and distribution of DOX from BSA-gel-capsules were studied. Afterwards, MCF-7/ADR xenografts tumor model was established in nude mice. The in vivo antitumor efficacy of DOX-loaded BSA-gel-capsules by intratumor injection was then evaluated.

RESULT

Compared with free DOX, more effective cytotoxicity against MCF-7/ADR cells after treatment with DOX-loaded BSA-gel-capsules was revealed, demonstrating the positive reversal effect on drug-resistance. Thereafter, the more cellular uptake and nucleus distribution of DOX from BSA-gel-capsules in MCF-7/ADR cells provided convincing explanation for the reversal effect. DOX-loaded BSA-gel-capsules displayed remarkably more antitumor efficacy than free DOX in MCF-7/ADR cell-xenografted mice. Finally, the high DOX accumulation and prolonged retention in tumor site after local administration of DOX-loaded BSA-gel-capsules was demonstrated, displaying the unique advantages of BSA-gel-capsules for local chemotherapy.

CONCLUSION

These findings indicate that DOX-loaded BSA-gel-capsules should be considered a potential candidate for the treatment of drug-resistant breast cancer. This paper provides a feasibility for the local chemotherapy of polyelectrolyte microcapsules, which will be a big step towards their application as drug delivery vehicles.

Nanoparticles for Immune Cytokine TRAIL-Based Cancer Therapy

The immune cytokine tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has received significant attention as a cancer therapeutic due to its ability to selectively trigger cancer cell apoptosis without causing toxicity in vivo. While TRAIL has demonstrated significant promise in preclinical studies in mice as a cancer therapeutic, challenges including poor circulation half-life, inefficient delivery to target sites, and TRAIL resistance have hindered clinical translation. Recent advances in drug delivery, materials science, and nanotechnology are now being exploited to develop next-generation nanoparticle platforms to overcome barriers to TRAIL therapeutic delivery. Here, we review the design and implementation of nanoparticles to enhance TRAIL-based cancer therapy. The platforms we discuss are diverse in their approaches to the delivery problem and provide valuable insight into guiding the design of future nanoparticle-based TRAIL cancer therapeutics to potentially enable future translation into the clinic.

Multifunctionalized polyethyleneimine-based nanocarriers for gene and chemotherapeutic drug combination therapy through one-step assembly strategy

Gene therapy combined with chemotherapy to achieve synergistic therapeutic effects has been a hot topic in recent years. In this project, the human tumor necrosis factor-related apoptosis-inducing ligand-encoding plasmid gene (TRAIL) and doxorubicin (Dox)-coloaded multi-functional nanocarrier was constructed based on the theory of circulation, accumulation, internalization, and release. Briefly, polyethyleneimine (PEI) was selected as skeleton material to synthesize PEI–polyethylene glycol (PEG)–TAT (PPT). Dox was conjugated to PEI using C6-succinimidyl 6-hydrazinonicotinate acetone hydrazone (C6-SANH), and a pH-sensitive Dox-PEI (DP) conjugate was obtained. Then, intracellular cationic pH-sensitive cellular assistant PPT and DP were mixed to condense TRAIL, and TRAIL–Dox coloaded PPT/DP/TRAIL (PDT) nanocarriers were obtained by one-step assembly. TRAIL was completely condensed by DP or PPT when mass ratios (DP/PPT to TRAIL) were up to 100:64, which indicated that DP and PPT could be mixed at any ratio for TRAIL condensation. The intracellular uptake rate of PDT was enhanced (P<0.05) when the contents of PPT in PPT+DP increased from 0 to 30%. Free Dox and TRAIL-loaded nanocarriers (PPT/C6-SANH-PEI/TRAIL [PCT]) were selected as controls to verify the synergistic antitumor effects of PDT. Compared with free TRAIL, TRAIL-protein expression was upregulated by PDT and PCT on Western blotting assays. The in vitro cytotoxicity of PDT was significantly enhanced compared to free Dox and PCT (P<0.01). Furthermore, murine PDT nanocarriers showed higher in vivo antitumor ability than both the Dox group (P<0.05) and the murine PCT group (P<0.05). These results indicated that the TRAIL + Dox synergistic antitumor effect could be achieved by PDT, which paves the way to gene–drug combination therapy for cancer.

Nanomedicine applications in the treatment of breast cancer: current state of the art

Breast cancer is the most common malignant disease in women worldwide, but the current drug therapy is far from optimal as indicated by the high death rate of breast cancer patients. Nanomedicine is a promising alternative for breast cancer treatment. Nanomedicine products such as Doxil^® and Abraxane^® have already been extensively used for breast cancer adjuvant therapy with favorable clinical outcomes. However, these products were originally designed for generic anticancer purpose and not specifically for breast cancer treatment. With better understanding of the molecular biology of breast cancer, a number of novel promising nanotherapeutic strategies and devices have been developed in recent years. In this review, we will first give an overview of the current breast cancer treatment and the updated status of nanomedicine use in clinical setting, then discuss the latest important trends in designing breast cancer nanomedicine, including passive and active cancer cell targeting, breast cancer stem cell targeting, tumor microenvironment-based nanotherapy and combination nanotherapy of drug-resistant breast cancer. Researchers may get insight from these strategies to design and develop nanomedicine that is more tailored for breast cancer to achieve further improvements in cancer specificity, antitumorigenic effect, antimetastasis effect and drug resistance reversal effect.