Exosomes hold great potential to deliver therapeutic reagents for cancer treatment due to its inherent low antigenicity. However, several technical barriers need be overcome before widely clinical applications, such as low productivity and ineffective cancer targeting. The present study aimed at creating a new biomanufacturing platform of cancer-targeted exosomes for drugs delivery.Specifically, we created a scalable, robust, high-yield, cell line-based exosomes production process in stirred-tank bioreactor, and developed an efficient surface tagging technique to generate mAbexosomes. The in vitro characterization using transmission electron microscopy, NanoSight nanoparticle tracking analysis and Western blotting confirmed the high quality of exosomes. Flow cytometry and confocal laser scanning microscopy imaging demonstrated mAb-exosomes had strong surface binding to cancer cells. Furthermore, to validate the targeted drug delivery efficiency, we loaded Romidepsin, a histone deacetylase inhibitor, into mAb-exosomes. The in vitro anti-cancer toxicity study showed high cytotoxicity of mAb-exosome-Romidepsin to cancer cells. Finally, the in vivo study using tumor xenograft animal model validated the cancer targeting specificity, anti-cancer efficacy, and drug delivery capability of the targeted exosomes. In summary, we developed new techniques enabling targeted exosomes for drug delivery to support large-scale animal studies and facilitate the translation from research to clinics.

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Neuroendocrine (NE) cancers arise from cells within the neuroendocrine system. Chemotherapies and endoradiotherapy have been developed, but their clinical efficacy is limited. The objective of this study was to develop a dual-targeted extracellular vesicles (EV)-delivered combined therapies to treat NE cancer. Specifically, we produced EV in stirred-tank bioreactors and surface tagged both anti-somatostatin receptor 2 (SSTR 2) monoclonal antibody (mAb) and anti-C-X-C motif chemokine receptor 4 (CXCR4) mAb to generate mAbs-EV. Both live-cell confocal microscopy imaging and In Vivo Imaging System (IVIS) imaging confirmed that mAbs-EV specifically targeted and accumulated in NE cancer cells and NE tumor xenografts. Then the highly potent natural cytotoxic marine compound verrucarin A (Ver-A) with IC50 of 2.2–2.8 nM and microtubule polymerization inhibitor mertansine (DM1) with IC50 of 3.1–4.2 nM were packed into mAbs-EV. The in vivo maximum tolerated dose study performed in non-tumor-bearing mice indicated minimal systemic toxicity of mAbs-EV-Ver-A/DM1. Finally, the in vivo anticancer efficacy study demonstrated that the SSTR2/CXCR4 dual-targeted EV-Ver-A/DM1 is more effective to inhibit NE tumor growth than the single targeting and single drug. The results from this study could expand the application of EV to targeting deliver the combined potent chemotherapies for cancer treatment.

Evidence suggests that mitochondrial network integrity is impaired in cardiomyocytes from failing hearts. While oxidative stress has been implicated in heart failure (HF)-associated mitochondrial remodeling, the effect of mitochondrial-targeted antioxidants, such as mitoquinone (MitoQ), on the mitochondrial network in a model of HF (e.g., pressure overload) has not been demonstrated. Furthermore, the mechanism of this regulation is not completely understood with an emerging role for posttranscriptional regulation via long noncoding RNAs (lncRNAs). We hypothesized that MitoQ preserves mitochondrial fusion proteins (i.e., mitofusin), likely through redox-sensitive lncRNAs, leading to improved mitochondrial network integrity in failing hearts. To test this hypothesis, 8-wk-old C57BL/6J mice were subjected to ascending aortic constriction (AAC), which caused substantial left ventricular (LV) chamber remodeling and remarkable contractile dysfunction in 1 wk. Transmission electron microscopy and immunostaining revealed defective intermitochondrial and mitochondrial-sarcoplasmic reticulum ultrastructure in AAC mice compared with sham-operated animals, which was accompanied by elevated oxidative stress and suppressed mitofusin (i.e., Mfn1 and Mfn2) expression. MitoQ (1.36 mg·day−1·mouse−1, 7 consecutive days) significantly ameliorated LV dysfunction, attenuated Mfn2 downregulation, improved interorganellar contact, and increased metabolism-related gene expression. Moreover, our data revealed that MitoQ alleviated the dysregulation of an Mfn2-associated lncRNA (i.e., Plscr4). In summary, the present study supports a unique mechanism by which MitoQ improves myocardial intermitochondrial and mitochondrial-sarcoplasmic reticulum (SR) ultrastructural remodeling in HF by maintaining Mfn2 expression via regulation by an lncRNA. These findings underscore the important role of lncRNAs in the pathogenesis of HF and the potential of targeting them for effective HF treatment. NEW & NOTEWORTHY We have shown that MitoQ improves cardiac mitochondrial network integrity and mitochondrial-SR alignment in a pressure-overload mouse heart-failure model. This may be occurring partly through preventing the dysregulation of a redox-sensitive lncRNA-microRNA pair (i.e., Plscr4-miR-214) that results in an increase in mitofusin-2 expression.

Adeno-associated viruses (AAVs) have been well characterized and used to deliver therapeutic genes for diseases treatment in clinics and basic research. This study used the triple transient transfection of AAV-DJ/8 as a model expression system to develop and optimize the laboratory production of AAV for research and pre-clinical applications. Specifically, various production parameters, including host cell, transfection reagent, cell density, ratio of plasmid DNA and cells, gene size, and production mode, were tested to determine the optimal process. Our results showed that the adherent production using HEK 293AAV with calcium transfection generated the highest volumetric productivity of 7.86 × 109 gc/ml. The optimal suspensive production using HEK 293F had best AAV productivity of 5.78 × 109 gc/ml in serum-free medium under transfection conditions of transfection density of 0.4 × 106 cells/ml, plasmid DNA:cells ratio of 1.6 µg:106 cells and synthesized cationic liposomes as transfection reagent. The similar AAV productivity was confirmed at scales of 30–450 ml in shaker and/or spinner flasks. The in vitro transfection and in vivo infection efficiency of the harvested AAV-DJ/8 carrying luciferase reporter gene was confirmed using cell line and xenograft mouse model, respectively. The minimal or low purification recovery rate of AAV-DJ/8 in ion-exchange chromatography column and affinity column was observed in this study. In summary, we developed and optimized a scalable suspensive production of AAV to support the large-scale preclinical animal studies in research laboratories.