Triptolide suppresses the growth and metastasis of non-small cell lung cancer by inhibiting ß-catenin-mediated epithelial-mesenchymal transition.

Non-small cell lung cancer (NSCLC) is characterized by a high incidence of metastasis and poor survival. As epithelial-mesenchymal transition (EMT) is well recognized as a major factor initiating tumor metastasis, developing EMT inhibitor could be a feasible treatment for metastatic NSCLC. Recent studies show that triptolide isolated from Tripterygium wilfordii Hook F attenuated the migration and invasion of breast cancer, colon carcinoma, and ovarian cancer cells, and EMT played important roles in this process. In the present study we investigated the effect of triptolide on the migration and invasion of NSCLC cell lines. We showed that triptolide (0.5, 1.0, 2.0 nM) concentration-dependently inhibited the migration and invasion of NCI-H1299 cells. Triptolide treatment concentration-dependently suppressed EMT in NCI-H1299 cells, evidenced by significantly elevated E-cadherin expression and reduced expression of ZEB1, vimentin, and slug. Furthermore, triptolide treatment suppressed ß-catenin expression in NCI-H1299 and NCI-H460 cells, overexpression of ß-catenin antagonized triptolide-caused inhibition on EMT, whereas knockout of ß-catenin enhanced the inhibitory effect of triptolide on EMT. Administration of triptolide (0.75, 1.5 mg/kg per day, ip, every 2 days) for 18 days in NCI-H1299 xenograft mice dose-dependently suppressed the tumor growth, restrained EMT, and decreased lung metastasis, as evidence by significantly decreased expression of mesenchymal markers, increased expression of epithelial markers as well as reduced number of pulmonary lung metastatic foci. These results demonstrate that triptolide suppresses NSCLC metastasis by targeting EMT via reducing ß-catenin expression. Our study implies that triptolide may be developed as a potential agent for the therapy of NSCLC metastasis.

Bismuth chelate as a contrast agent for X-ray computed tomography.

BACKGROUNDS: Due to the unexpected side effects of the iodinated contrast agents, novel contrast agents for X-ray computed tomography (CT) imaging are urgently needed. Nanoparticles made by heavy metal elements are often employed, such as gold and bismuth. These nanoparticles have the advantages of long in vivo circulation time and tumor targeted ability. However, due to the long residence time in vivo, these nanoparticles may bring unexpected toxicity and, the preparation methods of these nanoparticles are complicated and time-consuming. METHODS: In this investigation, a small molecular bismuth chelate using diethylenetriaminepentaacetic acid (DPTA) as the chelating agent was proposed to be an ideal CT contrast agent. RESULTS: The preparation method is easy and cost-effective. Moreover, the bismuth agent show better CT imaging for kidney than iohexol in the aspect of improved CT values. Up to 500 µM, the bismuth agent show negligible toxicity to L02 cells and negligible hemolysis. And, the bismuth agent did not induce detectable morphology changes to the main organs of the mice after intravenously repeated administration at a high dose of 250 mg/kg. The pharmacokinetics of the bismuth agent follows the first-order elimination kinetics and, it has a short half-life time of 0.602 h. The rapid clearance from the body promised its excellent biocompatibility. CONCLUSIONS: This bismuth agent may serve as a potential candidate for developing novel contrast agent for CT imaging in clinical applications.

CuS Nanodot-Loaded Thermosensitive Hydrogel for Anticancer Photothermal Therapy.

The purpose of this research is to establish an injectable hydrogel encapsulating copper sulfide (CuS) nanodots for photothermal therapy against cancer. The CuS nanodots were prepared by one-pot synthesis, and the thermosensitive Pluronic F127 was used as the hydrogel matrix. The CuS nanodots and the hydrogel were characterized by morphous, particle size, serum stability, photothermal performance upon repeated 808 nm laser irradiation, and rheology features. The effects of the CuS nanodots and the hydrogel were evaluated qualitatively and quantitatively in 4T1 mouse breast cancer cells. The retention, photothermal efficacy, therapeutic effects, and systemic toxicity of the hydrogel were assessed in tumor bearing mouse model. The CuS nanodots with a diameter of about 8 nm exhibited satisfying serum stability, photoheat conversion ability, and repeated laser exposure stability. The hydrogel encapsulation did not negatively influence the above features of the photothermal agent. The nanodot-loaded hydrogel shows a phase transition at body temperature and, as a result, a long retention in vivo. The photothermal-agent-embedded hydrogel played a promising photothermal therapeutic effect in the tumor bearing mouse model with low systemic toxicity after peritumoral administration.

Exosomal cargo-loading and synthetic exosome-mimics as potential therapeutic tools.

Exosomes are nano-sized vesicles that serve as mediators for intercellular communication through the delivery of cargo, including protein, lipids, nucleic acids or other cellular components, to neighboring or distant cells. Exosomal cargo may vary in response to different physiological or pathological conditions. The endosomal sorting complex required for transport (ESCRT) family has been widely accepted as a key mechanism in biogenesis and cargo sorting. On the other hand, accumulating evidence show that ESCRT-independent pathways exist. Due to the critical role of exosomes in intercellular communications in delivering cargo to recipient cells, exosomes have been investigated as a vector for the delivery of endogenous or exogenous cargo for therapeutic purposes. But the number of exosomes produced by cells is limited, which hampers their application. Synthetic exosome-mimics have been fabricated and investigated as a therapeutic tool for drug delivery. This review focuses on ESCRT-independent regulation of cargo loading into exosomes, including lipid raft and ceramide-mediated mechanisms, and reported exosomes or exosome-mimics with therapeutic effects.

Susceptibility-weighted imaging of the venous networks around the brain stem.

INTRODUCTION: The venous network of the brainstem is complex and significant. Susceptibility-weighted imaging (SWI) is a practical technique which is sensitive to veins, especially tiny veins. Our purpose of this study was to evaluate the visualization of the venous network of brainstem by using SWI at 3.0 T. METHODS: The occurrence rate of each superficial veins of brainstem was evaluated by using SWI on a 3 T MR imaging system in 60 volunteers. The diameter of the lateral mesencephalic vein and peduncular vein were measured by SWI using the reconstructed mIP images in the sagittal view. And the outflow of the veins of brainstem were studied and described according to the reconstructed images. RESULTS: The median anterior pontomesencephalic vein, median anterior medullary vein, peduncular vein, right vein of the pontomesencephalic sulcus, and right lateral anterior pontomesencephalic vein were detected in all the subjects (100%). The outer diameter of peduncular vein was 1.38 ± 0.26 mm (range 0.8-1.8 mm). The lateral mesencephalic vein was found in 75% of the subjects and the mean outer diameter was 0.81 ± 0.2 mm (range 0.5-1.2 mm). The inner veins of mesencephalon were found by using SWI. CONCLUSION: The venous networks around the brain stem can be visualized by SWI clearly. This result can not only provide data for anatomical study, but also may be available for the surgical planning in the infratentorial region.

Ultra performance liquid chromatography-tandem mass spectrometry assay for the quantification of RNA and DNA methylation.

Previous studies have reported that nucleic acid methylation is a critical element in cardiovascular disease, and most studies mainly focused on sequencing and biochemical research. Here we developed an Ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method for the quantification analysis of the dissociative epigenetic modified nucleosides (5mdC, 5mrC, m6A) in Myocardial Infarction (MI) SD rats from different periods (1 week, 4 weeks, 8 weeks) after the surgery. The samples for analysis were obtained from heart tissue and blood of the rats. All the quantification results are compared with the sham-operated group. Total RNA and DNA were isolated by enzymatic hydrolytic methods before the UPLC-MS/MS analysis. The statistical analysis demonstrates the dynamic changes of modified nucleosides in MI rats, and it showed good specificity, accuracy, stability and less samples were needed in the method. In this paper, we discovered that the concentration of 5mdC, 5mrC, m6A from heart tissue significantly increased at 8 weeks after the surgery. Furthermore, UPLC-MS/MS helps us observe the similar change of the concentration of those 3 methylated biomarkers in peripheral blood after 8 weeks. The result shows that the dynamic process of those 3 methylated biomarkers in peripheral blood is related to the content of methylated biomarkers from the heart tissue. Based on the scientific evidence available, we proved that the methylation of genetic materials in peripheral blood is similar to myocardial infarction tissue. The relation between them indicates that peripheral blood could be a promising alternative to the heart tissue which monitor the level of methylation and MI diagnosis-aided.