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We aimed to study the regulatory roles and mechanism of circular nuclear factor IX (circNFIX) in cancer growth and stemness properties of ovarian cancer (OC). CircNFIX and SH3RF3 levels in OC tissues and cells were tested by quantitative real‐time PCR. RNase R treatment quantified circNFIX RNA stability. Molecular interaction among circNFIX, LIN28B, and SH3RF3 was predicted by bioinformatics software and validated through RNA immunoprecipitation (RIP) assay. The gain‐ or loss‐experiments of circNFIX on capabilities of metastasis and stemness in vitro were assessed using Cell Counting Kit‐8, Transwell, western blot, and sphere‐formation assays. CircNFIX and SH3RF3 were markedly elevated in OC tissues and OC cells. Knocking down circNFIX repressed the proliferation, migration, invasion, and stemness properties of A2780 and SKOV3 cells. The RIP assay verified the direct binding relationship between LIN28B, circNFIX, and SH3RF3. Additionally, overexpression of circNFIX elevated the SH3RF3 expression, while this effect was reversed by LIN28B silence. Rescue experiments demonstrated that the overexpression of SH3RF3 reversed the knockdown of circNFIX on OC cells' proliferation, metastasis, and stemness properties. CircNFIX improved the mRNA stability and translation of SH3RF3 via recruiting LIN28B, thus promoting the proliferation, invasion, and stemness properties of OC cells in vitro.

Ovarian cancer (OC) is a gynecological cancer with high mortality. OC‐derived exosomal circRNAs can regulate angiogenesis. This study aims to explore the role and mechanism of exosomal circRNA nuclear factor I X(CircNFIX) derived from OC cells in angiogenesis. Quantitative real‐time polymerase chain reaction was employed to evaluate the levels of circNFIX, miR‐518a‐3p, and tripartite motif protein 44(TRIM44) in OC and adjacent tissues. Exosomes from the ovarian surface epithelial cell (HOSEpiC) and OC cells (SKOV3 or OVCAR3) were isolated by differential centrifugation. Exosomes were cocultured with the human umbilical vein endothelial cells (HUVECs). The angiogenesis capacity was analyzed by Tube formation assay. 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2‐H‐tetrazolium bromide (MTT) and Transwell assays were used to determine the cell viability and migration ability. The dual‐luciferase report, RNA immunoprecipitation (RIP), and RNA pull‐down assays were applied to validate the gene's interaction. CircNFIXand TRIM44expression were higher and miR‐518a‐3pwas lower in OC tissues than in the adjacent tissues. Upregulated circNFIXand TRIM44were significantly correlated with the tumor size and International Federation of Gynecology and Obstetrics (FIGO) stage of OC patients. HUVECs treated OC‐derived exosomes had higher proliferation, migration, and angiogenesis capacities than the control group. While OC‐derived exosomal circNFIXsilencing restrained HUVECs' proliferation, migration, and angiogenesis, compared with the OC‐derived exosomes group. OC‐derived exosomal circNFIXpositively regulated TRIM44expression by targeting miR‐518a‐3pin HUVECs. OC‐derived exosomal circNFIXpromoted angiogenesis by regulating the Janus‐activated kinase/signal transducer and activator of transcription 1 (JAK/STAT1) pathway via miR‐518a‐3p/TRIM44axis in HUVECs.

ABSTRACTSAR Interferometry (InSAR) is a powerful technique for mapping land surface deformation, but single one-dimensional (1D) InSAR line-of-sight (LOS) measurement limits its application in three-dimensional (3D) displacement retrieval. Traditional methods were developed for measuring large-scale deformation. In this paper, to retrieve the slow 3D deformation process in the Jiaju landslide, a surface-parallel flow model is applied, according to the existing geological data gained from this landslide. Nine ENVISAT ASAR images and 19 ALOS PALSAR images were collected to reconstruct the 3D deformation field. An iterative method for correcting the characteristic value (IMCCV) with maximum likelihood estimation (M-estimation) adaptively generates an accurate stochastic model. The 3D deformation measurements show that the northern part of the Jiaju landslide clearly had horizontal deformation with the largest deformation velocity exceeding 15 cm year−1, while the southern part was relatively stable. Similarly, large vertical deformation appeared in the northern part (−2 cm year−1) and little deformation occurred in the southern part (−0.5 cm year−1). Compared with GPS measurements, the standard deviation is 1.4 cm year−1and 0.7 cm year−1in horizontal and vertical directions, respectively. Therefore, the Jiaju landslide exhibited movements in the horizontal direction accompanied by slight settlement in the vertical direction.

Theranostics is a new trend in the tumor research field, which involves the integration of diagnostic and therapeutic functions using imageable nanoparticles coupled with therapeutic drugs. Imaging-guided targeted delivery of therapeutics and diagnostics using nanocarriers hold great promise to minimize the side effects of conventional chemotherapy. Ultrasound microbubbles have been employed as theranostic agents over the last decade, which provide both real-time dynamic imaging for diagnosis and precise control for targeted tumor therapy. However, the intrinsic defects of microbubbles such as poor tissue penetration, short circulation time and instability hinder microbubble-based theranostic applications. In recent years, liquid-to-gas transitional perfluorocarbon nanoparticles have been developed as promising diagnostic and therapeutic nanoagents to solve the abovementioned problems. In this study, phase-changeable, folate-targeted perfluoropentane nanodroplets loaded with 10-hydroxycamptothecin (HCPT) and superparamagnetic Fe3O4(denoted as FA-HCPT-Fe3O4-PFP NDs) are prepared and investigated for multimodal tumor imaging and targeted therapy. After intravenous administration into nude mice bearing SKOV3 ovarian cancer, FA-HCPT-Fe3O4-PFP NDs exhibit the ability to enhance MR and PA imaging. Furthermore, after the phase transition activated by low-intensity focused ultrasound (LIFU) sonication, FA-HCPT-Fe3O4-PFP NDs remarkably enhance US imaging at the tumor location. Meanwhile, the HCPT released from FA-HCPT-Fe3O4-PFP NDs during the liquid-to-gas transition provides a therapeutic effect on tumor cells with relatively low side effects to normal tissue. Therefore, the combination of LIFU and FA-HCPT-Fe3O4-PFPNDs presents an ideal modality for tumor-targeted theranostics.

Expression of Concern for ‘Low-intensity focused ultrasound (LIFU)-activated nanodroplets as a theranostic agent for noninvasive cancer molecular imaging and drug delivery’ by Jianxin Liu et al., Biomater. Sci., 2018, 6, 2838–2849, https://doi.org/10.1039/C8BM00726H.

With the formation of mesa-like cells at their surfaces, LiNbO3thin films are useful for integrating high-density domain wall memory. However, the material is too hard and inert to etch the cells with inclined side edges that help to diminish polarization retention. Moreover, etching could damage the ferroelectricity of the film. To overcome these drawbacks in forming memory cells directly, we developed a technique to deposit two gapped electrodes in the film surface, without needing to etch the film. While applying an in-plane write voltage above a coercive voltage, the domain within the gap is reversibly switched along with the creation/erasure of conducting domain walls against the peripheral unswitched domain. This technique enables “on”/“off” current read of the written information. Unfortunately, the switched domain within the gap generally has poor retention and a weak wall current arises from the presence of a strong depolarization field. To overcome this problem, we fabricated a type of embedded electrode that diffuses thickness-wise into the LiNbO3thin film to form a parallel-plate-like structure to screen the depolarization field. The switched domains now had good retention and carry large wall currents. Alternatively, without the embedded electrodes, the switched domains within the cells can be stabilized with increasing gap distance above a critical length of 320 nm. The two methods foreshadow the possibility in the future to fabricate damage-free LiNbO3memory cells without etching.