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Strategies for treating brain metastases of breast cancer have demonstrated limited efficacy due to the blood-brain barrier (BBB). Gene therapy could improve the efficacy of chemotherapeutic drugs. Exosomes derived from the mesenchymal stem cells (MSCs) are small membrane-based gene vectors that can pass through the BBB. CXCR4 is the most commonly found chemokine receptor in human cancer cells. Furthermore, the SDF-1/CXCR4 axis plays an important role in the homing of MSCs for tumor cell diffusion and metastasis. TRAIL can selectively induce apoptosis in transformed cells without significant toxic side effects in normal tissues. In this study, exosomes were isolated from MSC CXCR4+TRAIL transduced with CXCR4 and TRAIL using a lentiviral vector. Synergistic antitumor study showed that exosome CXCR4+TRAIL exerted significant activity as a cooperative agent with carboplatin in an MDA-MB-231Br SCID mouse model, potentially engendering a novel strategy for advancing the treatment of brain metastases of breast cancer. Based on this study, further investigation of the effect of the vector on BBB and inducing apoptosis of brain tumors is warranted. In addition, the safety of the vector in animals during the treatment needs to be evaluated.

PurposeBoron neutron capture therapy (BNCT) is an emerging binary radiotherapy, which is limited for application due to the challenge of targeted delivery into tumor nowadays. Here, we propose the use of iRGD-modified polymeric nanoparticles for active targeted delivery of boron and doxorubicin (DOX) in BNCT.Methods10B-enriched BSH was covalently grafted to PEG-PCCL to prepare 10B-polymer, then surface-modified with iRGD. And, DOX was physically incorporated into polymers afterwards. Characterization of prepared polymers and in vitro release profile of DOX from polymers were determined by several methods. Cellular uptake of DOX was observed by confocal microscope. Accumulation of boron in cells and tissues was analyzed by ICP-MS. Biodistribution of DOX was studied by ex vivo fluorescence imaging and quantitative measurement. Tumor vascular normalization of Endostar for promoting delivery efficiency of boron on refractory B16F10 tumor was also studied.ResultsThe polymers were monodisperse and spheroidal in water with an average diameter of 24.97 nm, which were relatively stable at physiological pH and showed a sustained release of DOX, especially at endolysosomal pH. Enhanced cellular delivery of DOX was found in iRGD-modified polymer group. Cellular boron uptake of iRGD-modified polymers in A549 cells was remarkably raised fivefold (209.83 ng 10B/106 cells) compared with BSH. The polymers represented prolonged blood circulation, enhanced tumor accumulation of 10B against BSH, and favorable tumor:normal tissue boron concentration ratios (tumor:blood = 14.11, tumor:muscle = 19.49) in A549 tumor-bearing mice 24 hrs after injection. Both fluorescence imaging and quantitative measurement showed the highest tumor accumulation of DOX at 24 hrs after injecting of iRGD-modified polymers. Improvement of vascular integrity and reduction of vascular mimicries were found after Endostar injection, and raised tumor accumulation of boron as well.ConclusionThe developed nanoparticle is an inspiring candidate for the safe clinical application for BNCT.

Diacid metabolite as the stable form of norcantharidin (DM-NCTD) derived from Chinese blister beetle (Mylabris spp.). The previous studies reported that DM-NCTD could enhance ABT-737-triggered cell viability inhibition and apoptosis in hepatocellular carcinoma (HCC) cell lines. To translate this synergistic therapy into in vivo anticancer treatment, a folate receptor-targeted lipid bilayer-supported chlorodimethyloctadecylsilane-modified mesoporous silica nanoparticle (FA-LB-CHMSN) with DM-NCTD loaded in CHMSN and ABT-737 in lipid bilayer was prepared, which could promote the cancer cell uptake of the drugs through folate receptor-mediated endocytosis. The structure and the properties of the nanoparticle were evaluated. FA-LB-CHMSN with DM-NCTD/ABT-737 loaded induced apparent tumor cell apoptosis and showed remarkably tumor inhibition in H22 tumor-bearing mice model, with significant cellular apoptosis in the tumor and no obvious toxicity to the tissues. We expect that this nanoparticle could be of interest in both biomaterial investigations for HCC treatment and the combination of chemotherapeutic drugs for synergistic therapies.

Background/Aims: Genetic modification of mesenchymal stem cells (MSCs) is an essential requirement for their use as a delivery vehicle. To achieve higher transfection efficiency and better reproducibility than previously synthesized chitosan (100 kDa)-polyethylenimine (PEI; 1200 Da), we synthesized a low molecular weight PEI (1200 Da)-grafted chitosan (50 kDa) (CP). Methods: Safety of CP/DNA or PEI (25 kDa)/DNA was evaluated by an MTT assay using A549 cells or MSCs and a zebrafish embryo model. Effects of CP/DNA on the characteristics of MSCs were evaluated using flow cytometry. Additionally, a pGL3 plasmid was used to investigate the transfection efficiency of PEI (25 kDa), chitosan (100 kDa)-PEI (1200 Da), and CP with different N/P mass ratios on A549 cells and MSCs. Furthermore, CP/pGL3 was used to investigate the effect of serum on transfection, and intracellular transport was assessed by observing the intracellular location of DNA using laser scanning confocal microscopy. In addition, the effect of endocytosis on transfection efficiency was evaluated using A549 cells pre-treated with different inhibitors. Investigations related to analysis of transfection efficiency were all performed using the BCA protein assay to standardize the data. Furthermore, TGF-β1-and CXCR4-expressing plasmids were applied to evaluate the gene transfer efficiency of CP, including its effects on the osteogenic differentiation and migratory ability of MSCs. Results: The safety evaluation demonstrated that CP/DNA had significantly lower toxicity than PEI (25 kDa)/DNA. Additionally, DNA entered MSCs transfected by CP without changing their properties, while the examination of intracellular transport demonstrated that CP/pGL3 was internalized rapidly into MSCs. Furthermore, studies of the internalization mechanism showed that CP/pGL3 complexes entered the cells through caveolae-mediated endocytosis, thereby suggesting that the CP coating helped DNA enter A549 cells without the requirement for receptors. Compared to PEI (25 kDa), the interference of serum on transfection was reduced significantly with the use of CP in both A549 cells and MSCs. To evaluate the effects of gene delivery using the constructed CP complex and the possibility of obtaining gene-engineered MSCs, TGF-β1- and CXCR4-expressing plasmids were successfully delivered into MSCs, confirming their ability to induce osteogenesis and change the migratory ability of MSCs, respectively. Conclusion: These results demonstrated that CP could be used to deliver genes into MSCs and could potentially be used in gene therapy based on MSCs.

Because norcantharidin (NCTD) is unstable and subject to ring opening and hydrolysis, the diacid metabolite of norcantharidin (DM-NCTD) is the stable form of NCTD found in normal saline solution. Conversion of NCTD to DM-NCTD is almost 100%, making it possible to determine and investigate the pharmacokinetics of DM-NCTD converted from NCTD. In this paper, a sensitive, simple and selective liquid chromatographic-tandem mass spectrometric method was developed and validated for determination of DM-NCTD in beagle plasma. DM-NCTD was detected in multiple-reaction monitoring (MRM) mode by using the dehydrated ion 169.3 as precursor ion and its product ion 123.1 as the detected ion. Ribavirin was used as internal standard and detected in MRM mode by use of precursor ions, resulting in a product ion transition of m/z 267.1 → 135.1. This method was successfully used for a pharmacokinetic study of DM-NCTD in beagles after intravenous administration of DM-NCTD in normal saline solution at doses of 0.39, 0.78, and 1.6 mg kg(-1). DM-NCTD had dose-dependent kinetics across the dosage range investigated, with enhanced T(1/2α) and AUC(0-12) and apparently decreasing V(d) and CL with increasing dosage. After single-dose administration, T(1/2α) ranged from 0.20 to 0.55 h, AUC(0-12) from 1.81 to 43.6 μg mL(-1) h(-1), V(d) from 228 to 55.9 mL kg(-1), and CL from 220 to 36.5 mL kg(-1) h(-1) (P < 0.01). The results indicated nonlinear pharmacokinetic behavior of DM-NCTD in beagles, suggesting that the risk of DM-NCTD in normal saline solution intoxication may be non-proportionally increased at higher doses.

Background Rhodojaponin III (RJ-III) is a bioactive diterpenoid, which is mainly found in Rhododendron molle G. Don (Ericaceae), a potent analgesia in traditional Chinese medicine with several years of clinical applications in the country. However, its clinical use is limited by its acute toxicity and poor pharmacokinetic profiles. To reduce such limitations, the current study incorporated RJ-III into the colloidal drug delivery system of hydroxypropyl trimethyl ammonium chloride chitosan (HACC)-modified solid lipid nanoparticles (SLNs) to improve its sustained release and antinociceptive effects in vivo for oral delivery. Results The optimized RJ-III@HACC-SLNs were close to spherical, approximately 134 nm in size, and with a positive zeta potential. In vitro experiments showed that RJ-III@HACC-SLNs were stable in the simulated gastric fluid and had a prolonged release in PBS (pH = 6.8). Pharmacokinetic results showed that after intragastric administration in mice, the relative bioavailability of RJ-III@HACC-SLNs was 87.9%. Further, it was evident that the peak time, half-time, and mean retention time of RJ-III@HACC-SLNs were improved than RJ-III after the administration. In addition, pharmacodynamic studies revealed that RJ-III@HACC-SLNs markedly reduced the acetic acid, hot, and formalin-induced nociceptive responses in mice ( P < 0.001), and notably increased the analgesic time ( P < 0.01). Moreover, RJ-III@HACC-SLNs not only showed good biocompatibility with Caco-2 cells in vitro but its LD 50 value was also increased by 1.8-fold as compared with that of RJ-III in vivo. Conclusion These results demonstrated that RJ-III@HACC-SLNs improved the pharmacokinetic characteristics of the RJ-III, thereby exhibiting toxicity-attenuating potential and antinociceptive enhancing properties. Consequently, HACC-SLNs loaded with RJ-III could become a promising oral formulation for pain management that deserves further investigation in the future.

Arthritis is a general term for various types of inflammatory joint diseases. The most common clinical conditions are mainly represented by rheumatoid arthritis and osteoarthritis, which affect more than 4% of people worldwide and seriously limit their mobility. Arthritis medication generally requires long-term application, while conventional administrations by oral delivery or injections may cause gastrointestinal side effects and are inconvenient for patients during long-term application. Emerging microneedle (MN) technology in recent years has created new avenues of transdermal delivery for arthritis drugs due to its advantages of painless skin perforation and efficient local delivery. This review summarizes various types of arthritis and current therapeutic agents. The current development of MNs in the delivery of arthritis drugs is highlighted, demonstrating their capabilities in achieving different drug release profiles through different self-enhancement methods or the incorporation of nanocarriers. Furthermore, the challenges of translating MNs from laboratory studies to the clinical practice and the marketplace are discussed. This promising technology provides a new approach to the current drug delivery paradigm in treating arthritis in transdermal delivery.