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ObjectiveThrough improving the potential of vascular endothelial growth factor receptor (VEGFR)-humanized mouse model (hKDR+/+) with C57BL/6N background to allow the growth of different mouse tumor cell lines, to establish novel tumor-bearing mouse models which can support in vivo tumorigenesis of different mouse tumor cell lines and be used to evaluate drugs targeting VEGFR. Methods Firstly, a method to evaluate the in vivo activity of antibody targeting VEGFR based on the hKDR+/+ humanized mouse model was established. Recombinant activating gene 1 (Rag1) knockout mice (Rag1-/-) were established using CRISPR/Cas9 technology. Then these Rag1-/- mice were crossed with hKDR+/+ mice to get a double gene modified homozygous hKDR+/+/Rag1-/- mouse model by screening. Finally, tumor cell lines derived from different mouse strains were tested on the double gene-modified mouse model to compare the differences in tumor growth.ResultsAntibodies designed for VEGFR showed significant anti-tumor activity in hKDR+/+ mice, which significantly reduced tumor volume and weight compared with the PBS group (P

The integration of complex oxides with a wide spectrum of functionalities on Si, Ge and flexible substrates is highly demanded for functional devices in information technology. We demonstrate the remote epitaxy of BaTiO3 (BTO) on Ge using a graphene intermediate layer, which forms a prototype of highly heterogeneous epitaxial systems. The Ge surface orientation dictates the outcome of remote epitaxy. Single crystalline epitaxial BTO3-δ films were grown on graphene/Ge (011), whereas graphene/Ge (001) led to textured films. The graphene plays an important role in surface passivation. The remote epitaxial deposition of BTO3-δ follows the Volmer-Weber growth mode, with the strain being partially relaxed at the very beginning of the growth. Such BTO3-δ films can be easily exfoliated and transferred to arbitrary substrates like Si and flexible polyimide. The transferred BTO3-δ films possess enhanced flexoelectric properties with a gauge factor of as high as 1127. These results not only expand the understanding of heteroepitaxy, but also open a pathway for the applications of devices based on complex oxides.

Vascular endothelial growth factor receptor 2 (VEGFR2)/KDR plays a critical role in tumor growth, diffusion, and invasion. The amino acid sequence homology of KDR between mouse and human in the VEGF ligand‐binding domain was low, thus the WT mice could not be used to evaluate Abs against human KDR, and the lack of a suitable mouse model hindered both basic research and drug developments. Using the CRISPR/Cas9 technique, we successfully inserted different fragments of the human KDR coding sequence into the chromosomal mouse Kdr exon 4 locus to obtain an hKDR humanized mouse that can be used to evaluate the marketed Ab ramucirumab. In addition, the humanized mAb VEGFR‐HK19 was developed, and a series of comparative assays with ramucirumab as the benchmark revealed that VEGFR‐HK19 has higher affinity and superior antiproliferation activity. Moreover, VEGFR‐HK19 selectively inhibited tumor growth in the hKDR mouse model but not in WT mice. The most important binding epitopes of VEGFR2‐HK19 are D257, L313, and T315, located in the VEGF binding region. Therefore, the VEGFR2‐HK19 Ab inhibits tumor growth by blocking VEGF‐induced angiogenesis, inflammation, and promoting apoptosis. To our best knowledge, this novel humanized KDR mouse fills the gaps both in an animal model and the suitable in vivo evaluation method for developing antiangiogenesis therapies in the future, and the newly established humanized Ab is expected to be a drug candidate possibly benefitting tumor patients. [ABSTRACT FROM AUTHOR]

The integration of complex oxides with a wide spectrum of functionalities on Si, Ge and flexible substrates is highly demanded for functional devices in information technology. We demonstrate the remote epitaxy of BaTiO3 (BTO) on Ge using a graphene intermediate layer, which forms a prototype of highly heterogeneous epitaxial systems. The Ge surface orientation dictates the outcome of remote epitaxy. Single crystalline epitaxial BTO3-δ films were grown on graphene/Ge (011), whereas graphene/Ge (001) led to textured films. The graphene plays an important role in surface passivation. The remote epitaxial deposition of BTO3-δ follows the Volmer-Weber growth mode, with the strain being partially relaxed at the very beginning of the growth. Such BTO3-δ films can be easily exfoliated and transferred to arbitrary substrates like Si and flexible polyimide. The transferred BTO3-δ films possess enhanced flexoelectric properties with a gauge factor of as high as 1127. These results not only expand the understanding of heteroepitaxy, but also open a pathway for the applications of devices based on complex oxides. The integration of epitaxial complex oxides on semiconductor and flexible substrates is required but challenging. Here, the authors report the highly heterogeneous epitaxy of transferrable BaTiO3-δ membrane with enhanced flexoelectricity on Ge (011). [ABSTRACT FROM AUTHOR]