Exosomes are attractive nucleic-acid carriers because of their favourable pharmacokinetic and immunological properties and of their ability to penetrate physiological barriers that are impermissible to synthetic drug-delivery vehicles. However, inserting exogenous nucleic acids, especially large messenger RNAs (mRNAs), into cell-secreted exosomes leads to low yields. Here, we report a cellular-nanoporation method for the production of large quantities of exosomes containing therapeutic mRNAs and targeting peptides. We transfected various source cells with plasmid DNAs, and stimulated the cells with a focal and transient electrical stimulus that promotes the release of exosomes carrying transcribed mRNAs and targeting peptides. Compared to bulk electroporation and to other exosome-production strategies, cellular nanoporation produced up to 50-fold more exosomes and more than a 10 3 -fold increase in exosomal mRNA transcripts, even from cells with low basal levels of exosome secretion. In orthotopic PTEN-deficient glioma mouse models, mRNA-containing exosomes restored tumour-suppressor function, enhanced tumourgrowth inhibition, and increased animal survival. Cellular nanoporation may enable the use of exosomes as a universal nucleic-acid carrier for applications requiring transcriptional manipulation.

Abstract. Inflammation is regarded as one of the major hallmarks of tumors, and has a very close relationship with gastric cancer. Interleukin-33 (IL-33), a new member of the IL-1 family, plays an important role in both inflammatory disease and tumors. The present study was designed to explore the effects of IL-33 on the proliferation, drug sensitivity, and the invasiveness of gastric cancer cells in vitro. IL-33 at concentrations lower than 100 pg/ml did not alter the inhibitory rate of gastric cancer cells. Moreover, IL-33 at these low concentrations protected against platinum-induced apoptosis in various gastric cancer cell lines, yet not in normal gastric epithelial cells. We also found that IL-33 increased the activation of the JNK pathway, and enhanced the expression of ST2. Furthermore, SP600125, a selective inhibitor of the JNK pathway, significantly blocked the protective effects of IL-33 in gastric cancer cells. In addition, Matrigel invasion assay showed that IL-33 markedly promoted gastric cancer cell invasion. In conclusion, the present study demonstrated that IL-33 protected against platinum-induced apoptosis and promoted cell invasion via activation of the JNK pathway in gastric cancer cells. In light of the prevalence of platinumbased chemotherapeutics in the treatment of gastric cancer, our results suggest that the level of IL-33 should be monitored during the treatment of gastric cancer, particularly when using platinum-based chemotherapeutics. IntroductionGastric cancer is one of the most common types of cancers. Over 1.6 million individuals succumb to gastric cancer each year in China. The Chinese incidence of gastric cancer accounts for more than 40% of the worldwide occurrences. Moreover, the progression-free survival and overall survival rates of gastric cancer patients in China are much lower than those in Europe and the US. Therefore, research concerning the characteristics and pathogenesis of gastric cancer in Chinese patients is urgently needed.Gastric cancer can be influenced by a wide range of genetic and environmental factors. A clear association has been reported between gastric cancer and chronic inflammation (1-3). Pro-inflammatory factors, including interleukin-1 (IL-1), IL-6 and tumor necrosis factor (TNF), may not only play roles in inflammation-associated carcinogenesis (4), but may also influence the chemotherapeutic sensitivity during gastric cancer treatment (5,6). IL-33 (previously known as NF-HEV), an 18-kDa protein, is a new member of the IL-1 family (7). Traditionally, the IL-1 family is well known for their effects on host defense, immune regulation and inflammation (7). However, recent research suggests that the IL-1 family is also involved in cancer development. For example IL-18, another member of the IL-1 family, acts as a pleiotropic cytokine in many types of cancer cells, and influences the invasion of gastric cancer cells under hypoxia (8). A high level of IL-18 in serum has been intensively associated with a wide variety of tumors, such as hepatocellular (9) a...

Oligonucleotide (ON) drugs, including small interfering RNA (siRNA), microRNA (miRNA) and antisense oligonucleotides, are promising therapeutic agents. However, their low membrane permeability and sensitivity to nucleases present challenges to in vivo delivery. Chemical modifications of the ON offer a potential solution to improve the stability and efficacy of ON drugs. Combined with nanoparticle encapsulation, delivery at the site of action and gene silencing activity of chemically modified ON drugs can be further enhanced. In the present review, several types of ON drugs, selection of chemical modification, and nanoparticle-based delivery systems to deliver these ON drugs are discussed.

The success of messenger RNA therapeutics largely depends on the availability of delivery systems that enable the safe, effective and stable translation of genetic material into functional proteins. Here we show that extracellular vesicles (EVs) produced via cellular nanoporation from human dermal fibroblasts, and encapsulating mRNA encoding for extracellular-matrix α1 type-I collagen (COL1A1) induced the formation of collagen-protein grafts and reduced wrinkle formation in the collagen-depleted dermal tissue of mice with photoaged skin. We also show that the intradermal delivery of the mRNA-loaded EVs via a microneedle array led to the prolonged and more uniform synthesis and replacement of collagen in the dermis of the animals. The intradermal delivery of EV-based COL1A1 mRNA may make for an effective protein-replacement therapy for the treatment of photoaged skin.Recent developments in messenger RNA-modification techniques have enhanced the therapeutic efficiency of mRNA delivery and its potential for near-term clinical applications, including protein-replacement therapy and vaccination against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus 1,2 . However, the intrinsic inability and potential immunogenicity of mRNAs require that they be encapsulated within delivery vehicles. Current mRNA-delivery modalities centre on the usage of lipid nanoparticle (LNP) carriers for encapsulation and

Background/Aim: Glioma is a deadly form of brain cancer. Doxorubicin is cytotoxic against glioma cells. However, the blood-brain barrier (BBB) limits its ability to be delivered to the brain. Materials and Methods: Liposomes (R8PLP) formed from, 1,2-dioleoyl-3-trimethylammonium-propane chloride (DOTAP), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy-(polyethylene glycol)-2000] (PEG-DSPE), cholesterol and egg phosphatidylcholine (ePC) were modified by cellpenetrating peptide R8 conjugated with oleic acid as a novel method for delivering doxorubicin. The antitumor effect of R8PLP was evaluated by uptake, cytotoxicity and brain accumulation. Results: The size of R8PLP was 95 nm. Doxorubicin was loaded into R8PLP by active loading with more than 95% encapsulation efficiency. Cellular uptake of R8PLP by U87-MG cells was 8.6-fold higher than that of unmodified liposomes. R8PLP reduced cell viability by 16.18% and 18.11% compared to cholesterol-ePC-liposomes and free doxorubicin, respectively, at 3.6 μM after 24 h treatment. The biodistribution of doxorubicin in the brain was significantly improved by R8PLP. The area under the concentration-time curve (AUC 0.5-12 h) of R8PLP was 2.4-times higher than that of cholesterol-ePC-PEG-DSPE-liposomes. Conclusion: These results suggest that R8conjugated oleic acid-modified liposomes are effective delivery vehicles for glioma. Glioma is an aggressive malignant tumor in the brain, with high morbidity and mortality (1-3). The survival time of patients with glioma after diagnosis is about 12-15 months (4). Treatment options for glioma are limited; surgery is associated with recurrence (5, 6). Chemotherapy using agents for glioma is limited to temozolomide, which has limited efficacy. Doxorubicin is a potential treatment option (7). Unfortunately, the blood-brain barrier (BBB) limits drug delivery to the brain (8, 9), diminishing its effectiveness. Liposomes are nontoxic and nonimmunogenic drug delivery vehicles that have been used for doxorubicin delivery. However, delivery of liposomes across the BBB remains a great challenge. Cell-penetrating peptides are a class of short peptides shown to facilitate cellular uptake of biomolecules (10). In this study, liposomes were modified with a cell-penetrating peptide, octa-arginine (R8), which has been shown to improve brain delivery of agents in vivo (11, 12). Oleic acid was used to modify R8 to facilitate liposomal incorporation. Materials and Methods Materials. R8 was synthesized by GL Biochem Ltd.