Tumor-Derived Microvesicles Induce Proangiogenic Phenotype in Endothelial Cells via Endocytosis

Background: Increasing evidence indicates that tumor endothelial cells (TEC) differ from normal endothelial cells (NEC). Our previous reports also showed that TEC were different from NEC. For example, TEC have chromosomal abnormality and proangiogenic properties such as high motility and proliferative activity. However, the mechanism by which TEC acquire a specific character remains unclear. To investigate this mechanism, we focused on tumor-derived microvesicles (TMV). Recent studies have shown that TMV contain numerous types of bioactive molecules and affect normal stromal cells in the tumor microenvironment. However, most of the functional mechanisms of TMV remain unclear. Methodology/Principal Findings: Here we showed that TMV isolated from tumor cells were taken up by NEC through endocytosis. In addition, we found that TMV promoted random motility and tube formation through the activation of the phosphoinositide 3-kinase/Akt pathway in NEC. Moreover, the effects induced by TMV were inhibited by the endocytosis inhibitor dynasore. Our results indicate that TMV could confer proangiogenic properties to NEC partly via endocytosis. Conclusion: We for the first time showed that endocytosis of TMV contributes to tumor angiogenesis. These findings offer new insights into cancer therapies and the crosstalk between tumor and endothelial cells mediated by TMV in the tumor microenvironment

Effect of Hydration in Corona Layer on Structural Change of Thermo-Responsive Polymer Micelles

The effect of hydration in corona layer on temperature responsiveness of polymer micelles consisting of poly(N-vinyl pyrrolidone)-block-poly(n-octadecyl acrylate) (PVP-b-PODA) was investigated. Small-angle X-ray scattering and dynamic light scattering showed two-step shape change of PVP-b-PODA micelles around 45 and 65 °C with elevating temperature, although only one-step shape change was observed at 45 °C in cooling process. In the first step, shape of PVP-b-PODA micelles was changed from disk to ellipsoidal oblate at the melting temperature (Tm) of PODA, although similar micelles consisting of another amphiphilic block copolymers containing PODA simply changed from disk to sphere at the Tm with elevating temperature. PVP-b-PODA micelles changed to spherical shape above 65 °C. Two-dimensional (2D) 1H-NMR showed the PVP chains were perfectly dehydrated above 65 °C. Therefore, it was suggested that the appearance of ellipsoidal shape between Tm of PODA and 65 °C was caused owing to shape memory effect of pseudo network of corona layer due to robust hydration of PVP chains

Multi‐Functional MoO3 Doping of Carbon‐Nanotube Top Electrodes for Highly Transparent and Efficient Semi‐Transparent Perovskite Solar Cells

Abstract MoO3 doping of carbon‐nanotube top electrodes in perovskite solar cells is multi‐functional and facilitates p‐doping, favorable energy‐level alignment, and enhanced hole transport. The optimal layer thickness of MoO3 (8 nm) is determined for decreasing the sheet resistance of carbon‐nanotube electrodes without damaging the perovskite film. The sheet resistance decreases by approximately one‐third from its original value, which is a substantially better result than that previously reported for acid doping of carbon‐nanotube top electrodes. MoO3 deposition lowers the Fermi level of the carbon‐nanotube electrode, improving its energy‐level alignment and hole‐transfer performance. When coated with 2,2′,7,7′‐tetrakis[N,N‐di(4‐methoxyphenyl)amino]‐9,9′‐spirobifluorene (spiro‐MeOTAD), MoO3 crystallizes on the carbon nanotubes and further enhances hole collection. Semi‐transparent perovskite solar cells with MoO3‐doped carbon‐nanotube electrodes have a power conversion efficiency of 17.3% with a transmittance of approximately 60% (at a wavelength of 1000 nm). Because of their favorable transparency in the infrared region, these perovskite solar cells are evaluated for use in a tandem structure with silicon solar cells via computational simulations. The predicted device efficiency (23.7%) exceeds that of conventional indium‐tin‐oxide‐based tandem solar cells (23.0%)