Mitochondrial UQCC3 controls embryonic and tumor angiogenesis by regulating VEGF expression.

Mitochondria play important roles in angiogenesis. However, the mechanisms remain elusive. In this study, we found that mitochondrial ubiquinol-cytochrome c reductase complex assembly factor 3 (UQCC3) is a key regulator of angiogenesis. TALEN-mediated knockout of Uqcc3 in mice caused embryonic lethality at 9.5-10.5 days postcoitum, and vessel density was dramatically reduced. Similarly, knockout of uqcc3 in zebrafish induced lethality post-fertilization and impaired vascular development. Knockout of UQCC3 resulted in slower tumor growth and angiogenesis. Mechanistically, UQCC3 was upregulated under hypoxia, promoted reactive oxygen species (ROS) generation, enhanced HIF-1α stability and increased VEGF expression. Finally, higher expression of UQCC3 was associated with poor prognosis in multiple types tumors, implying a role for UQCC3 in tumor progression. In conclusion, our findings highlight the important contribution of UQCC3 to angiogenesis under both physiological and pathological conditions, indicating the potential of UQCC3 as a therapeutic target for cancer.

Novel EGFR­bispecific recombinant immunotoxin based on cucurmosin shows potent anti­tumor efficiency in vitro.

Epidermal growth factor receptor (EGFR) is overexpressed in various tumors and is associated with cancer initiation, progression, and poor prognosis. Despite the achievements made by tyrosine kinase inhibitors and monoclonal antibodies in certain cases, many patients have not benefited from such treatment due to resistance. Immunotoxins (ITs) are antibody­cytotoxin chimeric molecules with specific cell killing ability, which have achieved different degrees of success in the treatment of a wide range of cancers in clinical trials. The aim of the current study was to examine a novel targeting EGFR recombinant immunotoxin Bs/cucurmosin (CUS) generated by fusing CUS to the EGFR­specific nanobody 7D12­9G8. Bs/CUS was successfully expressed in Escherichia coli strain BL21 (DE3) in a soluble form. Furthermore, it retained binding capacity and specificity with EGFR and was superior to rE/CUS, a monospecific IT we reported previously. In vitro results showed that Bs/CUS could be internalized into the cytoplasm and selectively kill cells in the picomolar range. Flow cytometry showed that Bs/CUS killed the cells mediated by the apoptosis pathway. Taken together, results of the current study indicated that Bs/CUS is a promising candidate that should be further evaluated as a cancer therapeutic for the treatment of EGFR­positive tumors.

Ligand Size and Conformation Affect the Behavior of Nanoparticles Coated with in Vitro and in Vivo Protein Corona.

Protein corona is immediately established on the surface of nanoparticles upon their introduction into biological milieu. Several studies have shown that the targeting efficiency of ligand-modified nanoparticles is attenuated or abolished owing to the protein adsorption. Here, transferrin receptor-targeting ligands, including LT7 (CHAIYPRH), DT7 (hrpyiahc, all d-form amino acids), and transferrin, were used to identify the influence of the ligand size and conformation on protein corona formation. The results showed that the targeting capacity of ligand-modified nanoparticles was lost after incubation with plasma in vitro, whereas it was partially retained after in vivo corona formation. Results from sodium dodecyl sulfate polyacrylamide gel electrophoresis and liquid chromatography-mass spectrometry revealed the difference in the composition of in vitro and in vivo corona, wherein the ligand size and conformation played a critical role. Differences were observed in cellular internalization and exocytosis profiles on the basis of the ligand and corona source.

Influence of ligands property and particle size of gold nanoparticles on the protein adsorption and corresponding targeting ability.

Nanoparticulated vesicles were widely used for carriers of drugs and imaging probes. To improve the targeting delivery efficiency of these vesicles, ligands were often functionalized onto their surfaces. However, the interaction between vesicles and plasma proteins may cover the ligands and hinder the targeting delivery. It is important to address the potential influence of ligands modification on plasma protein adsorption and the following targeting delivery. In this study, two common used ligands were chosen as the model: transferrin and RGD peptide. Gold nanoparticles were utilized as model particles. Sodium dodecyl sulfate polyacrylamide gel electrophoresis data demonstrated that higher PEG modification and smaller particle size could reduce the plasma protein adsorption, while ligand modification could increase. The cellular uptake results showed that the targeting ability of smaller ligand RGD peptide would be more easily influenced by the proteins corona.

Evaluation of Novel Anticaries Adhesive in a Secondary Caries Animal Model.

We investigated the anticaries properties of an adhesive containing dimethylaminododecyl methacrylate (DMADDM) in vivo via a secondary caries animal model. Cavities were prepared in the maxillary first molars of Wistar rats. DMADDM-containing adhesives were applied on one side and commercial adhesives on the opposite side as a control. After a 3-week feeding period to induce secondary caries, the molars were harvested for the evaluation of the secondary caries. Lesion depth (LD) and mineral loss (ML) were measured via a micro-CT method, and a modified Keyes scoring method yielded scores for the caries lesions. Statistical analysis was divided into 2 parts: a correlation analysis between 2 evaluations with one-way ANOVA and a least-significant differences (LSD) test, and an evaluation of anticaries adhesives with a paired samples t test. The results showed that: (1) secondary caries was successfully produced in rats; (2) there was a correlation between the modified Keyes scoring method and micro-CT in the evaluation of the secondary caries; (3) the adhesive containing DMADDM significantly reduced both LD and ML (according to micro-CT), and also lowered the scores (based on the modified Keyes scoring method). This suggests that the novel DMADDM adhesive could perform an anticaries function in vivo via the secondary caries animal model which was also developed and testified in research. Secondary caries is one of the major reasons leading to the failure of caries restoration treatment. As a solution, anticaries adhesives perform well in biofilm inhibition in vitro. However, the lack of secondary caries animal models limits the evaluation of anticaries adhesives in vivo.

Ligand-Mediated and Enzyme-Directed Precise Targeting and Retention for the Enhanced Treatment of Glioblastoma.

Glioblastoma (GBM), one of the most lethal cancers, remains as a hard task to handle. The major hurdle of nanostructured therapeutic agents comes from the limited retention at the GBM site and poor selectivity. In this study, we reported dual-functional gold nanoparticles (AuNPs) to figure out the biological barrier and improve their accumulation in GBM. The nanoparticles, AuNP-A&C-R, were composed of two functional particles: one was Ala-Ala-Asn-Cys-Asp (AK) and R8-RGD-comodified AuNPs (AuNP-AK-R) and the other was 2-cyano-6-amino-benzothiazole and R8-RGD-comodified AuNPs (AuNP-CABT-R). AuNP-A&C-R could aggregate in the presence of legumain, resulting in a size increase from 41.4 ± 0.6 to 172.9 ± 10.2 nm after 8 h incubation. After entering the circulatory system, AuNP-A&C-R actively targeted the integrin αvß3 receptor on blood-brain barrier (BBB), mediated transcytosis of particles across BBB, and then targeted the receptor on the GBM cells. Once AuNP-A&C-R entered into GBM, they formed further aggregates with increased size extracellularly or intracellularly because of the overexpressed legumain, which in turn blocked their backflow to the bloodstream or limited their exocytosis by cells. In vivo optical imaging demonstrated that AuNP-A&C-R were efficiently delivered to the GBM site and retained with high selectivity. We further confirmed that AuNP-A&C-R acquired a higher accumulation at the GBM site than AuNP-A&C and AuNP-R because of the synergistic effect. More importantly, the doxorubicin (DOX)-loaded AuNP-A&C-R showed an improved chemotherapeutic effect to C6 GBM-bearing mice, which significantly prolonged the median survival time by 1.22-fold and 1.27-fold compared with the DOX-loaded AuNP-A&C and the DOX-loaded AuNP-R, respectively. These results suggested that the dual-functional nanoplatform is promising for the GBM treatment.

Antitumor and Antimetastasis Activities of Heparin-based Micelle Served As Both Carrier and Drug.

Effective treatments for tumors are not easy to achieve due to the existence of metastases, which are responsible for most tumor death. Hence, a new drug delivery system is a pressing need, which should be biocompatible, stimuli-responsive, and multifunctional, including antitumor, antimetastasis, and antiangiogenesis effects. However, it is challenging to achieve all of these properties in one drug delivery system. Here, we developed a system of drug DOX and heparin into one self-assemble nanoparticle via pH-sensitive hydrazone bond and hydrophobic groups, deoxycholate. In the process, heparin itself was not only as the hydrophilic segments of the carrier, but also processed multiple biological functions such as antiangiogenesis and antimetastasis effect. The micelle nanoparticle HD-DOX processed good stability and acidic pH-triggered drug release property. After systemic administration, heparin-based micelle nanoparticle showed longer half-time and enhanced accumulation of DOX in tumors through the enhanced permeability and retention effect, leading to more efficient antitumor effects. In addition, heparin could hinder platelet-induced tumor cells epithelial-mesenchymal transition (EMT) and partially affect cell actin cytoskeletal arrangement, resulting in the disorganization of the actin cytoskeleton. Therefore, HD-DOX exhibited significant inhibitory effect on the metastasis in melanoma animal model in C57BL/6 mouse. Meanwhile, benefited from the antiangiogenesis effect of heparin, tube formations in endothelial cells were effectively inhibited and tumor vascular density was decreased by HD-DOX. Taken together, our study developed a self-assembly nanoplatform that both the drug and carrier had therapeutic effects with ideal antitumor efficacy.

A simple one-step method for preparation of fluorescent carbon nanospheres and the potential application in cell organelles imaging.

Highly fluorescent carbon nanospheres with a quantum yield of 17.6% have been prepared by a one-step method with hydrothermal treatment of spider silk. Due to the high photostability, low toxicity and well blood compatibility, these carbon nanospheres could be used as an excellent probes for cancer cell imaging.