Construction of a cold island network for the urban heat island effect mitigation

The urban heat island (UHI) effect seriously challenges sustainable urban development strategies and livability. Numerous studies have explored the UHI problem from the perspective of isolated blue and green patches, ignoring the overall function of cold island networks. This study aims to explore the construction method of cold island network by integrating scattered cold island resources, rationally guiding urban planning and construction, and providing effective ideas and methods for improving the urban thermal environment. Taking the central city of Fuzhou as an example, the identification of the cold island core source (CICS) was optimized by applying relative land surface temperature (LST), morphological spatial pattern analysis, and landscape connectivity analysis. The combined resistance surface was constructed based on a spatial principal component analysis. Subsequently, the cold island network was constructed by applying circuit theory and identifying the key nodes. The results showed that the central and eastern parts of the study area experienced the most significant UHI effects and there was a tendency for them to cluster. Overall, 48 core sources, 104 corridors, 89 cooling nodes, and 34 heating nodes were identified. The average LST of the CICSs was 28.43 °C, significantly lower than the average LST of the entire study area (31.50 °C), and the 104 cold corridors were classified into three categories according to their importance. Different targeting measures should be adopted for the cooling and heating nodes to maintain the stability of the cold island network and prevent the formation of a heat network. Finally, we suggest a model for urban cold island network construction and explore methods for mitigating issues with UHI to achieve proactive and organized adaptation and mitigation of thermal environmental risks in urban areas, as well as to encourage sustainable urban development.

Single photon emitter deterministically coupled to a topological corner state

Incorporating topological physics into the realm of quantum photonics holds the promise of developing quantum light emitters with inherent topological robustness and immunity to backscattering. Nonetheless, the deterministic interaction of quantum emitters with topologically nontrivial resonances remains largely unexplored. Here we present a single photon emitter that utilizes a single semiconductor quantum dot, deterministically coupled to a second-order topological corner state in a photonic crystal cavity. By investigating the Purcell enhancement of both single photon count and emission rate within this topological cavity, we achieve an experimental Purcell factor of Fp = 3.7. Furthermore, we demonstrate the on-demand emission of polarized single photons, with a second-order autocorrelation function g(2)(0) as low as 0.024 ± 0.103. Our approach facilitates the customization of light-matter interactions in topologically nontrivial environments, thereby offering promising applications in the field of quantum photonics.

High-speed electro-optic modulation in topological interface states of a one-dimensional lattice

Electro-optic modulators are key components in data communication, microwave photonics, and quantum photonics. Modulation bandwidth, energy efficiency, and device dimension are crucial metrics of modulators. Here, we provide an important direction for the miniaturization of electro-optic modulators by reporting on ultracompact topological modulators. A topological interface state in a one-dimensional lattice is implemented on a thin-film lithium-niobate integrated platform. Due to the strong optical confinement of the interface state and the peaking enhancement of the electro-optic response, a topological cavity with a size of 1.6 × 140 μm2 enables a large modulation bandwidth of 104 GHz. The first topological modulator exhibits the most compact device size compared to reported LN modulators with bandwidths above 28 GHz, to the best of our knowledge. 100 Gb/s non-return-to-zero and 100 Gb/s four-level pulse amplitude modulation signals are generated. The switching energy is 5.4 fJ/bit, owing to the small electro-optic mode volume and low capacitance. The topological modulator accelerates the response time of topological photonic devices from the microsecond order to the picosecond order and provides an essential foundation for the implementation of large-scale lithium-niobate photonic integrated circuits.

Assessing the effects of topographic gradients on landscape patterns: The study case of Tingjiang river basin, China

With the progress of urbanization, the natural geographical characteristics of different river basins have also undergone tremendous changes, and bring many environmental and social issues. It is of great significance to the sustainable development of river basins to reveal the relationship between topographic and landscape patterns. Therefore, we selected Tingjiang river basin, utilizing remote sensing images from 1991, 2004, and 2017, as well as the digital elevation model (DEM) data, we computed a topographic classification system consisting of four levels (Low level, Low-medium level, Medium-high level, High level). This approach enables us to study the gradient impact of topography and investigate the mechanism influencing the landscape pattern. The results show: (1) Low-medium and medium-high topographic levels are dominant in the research sites, accounting 49.35% and 38.47%, respectively. (2) Bare land showed a significant decrease while construction, cultivated, and forest land increased from 1991 to 2017. (3) Forest land is mainly concentrated in the middle-high and high-topographic levels whereas construction land, cultivated land, water area and bare land are mainly concentrated in the middle-low and low-topographic level. (4) The landscape pattern significantly varies with the topographic gradient, where the conversion to construction land is widespread in the low-topographic area, while alternation between cultivated land and forest land mainly occurs in the medium-low and medium-high topographic areas. Consequently, these findings provide insights into the impact of topography on river basin landscape pattern, which could guide sustainable development in the future.

The Relationship between Landscape Construction and Bird Diversity: A Bibliometric Analysis

Urbanization development is the main cause of drastic habitat changes and biodiversity loss, and urban green space construction is one of the effective ways to mitigate biodiversity decay. The proper construction of urban green space landscapes can maintain or increase the resources provided by urban biodiversity, especially bird diversity. This paper is based on 4112 papers published in this research area between 2002 and 2022, and CiteSpace was used to conduct a bibliometric analysis of the research area in terms of the number of articles published, the country or region of publication, core authors, and academic development. The paper systematically reviews the hotspots, history, and frontiers of research on landscape architecture and bird diversity. At the same time, the relationship between landscape construction and bird diversity is discussed in the context of landscape features, vegetation characteristics, and human behavioral activities. The results revealed: (1) research on the association between landscape camping and bird diversity received high priority from 2002 to 2022. Moreover, this research area has become a mature discipline. (2) Throughout the research history, there are four research hotspots (fundamental research on bird communities, influencing factors related to changes in bird community characteristics, research on bird activity rhythms, and ecological and ornamental values of birds), four development stages (2002-2004, 2005-2009, 2010-2015, and 2016-2022), and several research frontiers. (3) Our aim was to reasonably consider the activity characteristics of birds in future landscape construction, and to thoroughly study the landscape construction strategies and management principles for the harmonious coexistence of humans and birds.

Percutaneous Transforaminal Endoscopic Discectomy Versus Microendoscopic Discectomy for Lumbar Disk Herniation: Five-year Results of a Randomized Controlled Trial

STUDY DESIGN

A prospective randomized controlled study.

OBJECTIVE

To compare the efficacy and safety between percutaneous transforaminal endoscopic discectomy (PTED) and microendoscopic discectomy (MED).

SUMMARY OF BACKGROUND DATA

Two kinds of minimally invasive discectomy, PTED and MED, are now widely used for treating lumbar disk herniation (LDH). The long-term comparative results of these two techniques still remained uncertain.

MATERIALS AND METHODS

In this single-center, open-label, randomized controlled trial, patients were included if they had persistent signs and symptoms of radiculopathy with corresponding imaging-confirmed LDH and were randomly allocated to PTED or MED groups. The primary outcome was the score of Oswestry Disability Index (ODI) and the secondary outcomes included the score of Medical Outcomes Study 36-Item Short-Form Health Survey bodily pain (SF36-BP) and physical function (SF36-PF), European Quality of Life-Five Dimensions (EQ-5D), Visual Analog Scales for back pain (VAS-back) and leg pain (VAS-leg).

RESULTS

A total of 241 patients were accepted to enroll in our randomized controlled trial, of which 119 were randomly assigned to the PTED group, and the rest 122 were assigned to the MED group. A total of 194 out of 241 patients (80.5%) completed the five-year follow-up. PTED group was associated with shorter postoperative in-bed time and length of hospital stay. Both primary and secondary outcomes did not differ significantly between the two treatment groups at each follow-up time point. During the five-year follow-up, seven recurrent cases occurred in PTED and MED groups, respectively.

CONCLUSION

Over the five-year follow-up period, PTED and MED were both efficacious in the treatment of LDH. The long-term clinical outcomes and recurrent rates were comparable between the treatment groups. PTED represents a more minimally invasive technique with the advantages of rapid recovery.

Neuronal differentiation drives the antitumor activity of mitogen-activated protein kinase kinase (MEK) inhibition in glioblastoma

Background

Epidermal growth factor receptor (EGFR) amplification is found in nearly 40%-50% of glioblastoma cases. Several EGFR inhibitors have been tested in glioblastoma but have failed to demonstrate long-term therapeutic benefit, presumably because of acquired resistance. Targeting EGFR downstream signaling with mitogen-activated protein kinase kinase 1 and 2 (MEK1/2) inhibitors would be a more effective approach to glioblastoma treatment. We tested the therapeutic potential of MEK1/2 inhibitors in glioblastoma using 3D cultures of glioma stem-like cells (GSCs) and mouse models of glioblastoma.

Methods

Several MEK inhibitors were screened in an unbiased high-throughput platform using GSCs. Cell death was evaluated using flow cytometry and Western blotting (WB) analysis. RNA-seq, real-time quantitative polymerase chain reaction, immunofluorescence, and WB analysis were used to identify and validate neuronal differentiation.

Results

Unbiased screening of multiple MEK inhibitors in GSCs showed antiproliferative and apoptotic cell death in sensitive cell lines. An RNA-seq analysis of cells treated with trametinib, a potent MEK inhibitor, revealed upregulation of neurogenesis and neuronal differentiation genes, such as achaete-scute homolog 1 (ASCL1), delta-like 3 (DLL3), and neurogenic differentiation 4 (NeuroD4). We validated the neuronal differentiation phenotypes in vitro and in vivo using selected differentiation markers (β-III-tubulin, ASCL1, DLL3, and NeuroD4). Oral treatment with trametinib in an orthotopic GSC xenograft model significantly improved animal survival, with 25%-30% of mice being long-term survivors.

Conclusions

Our findings demonstrated that MEK1/2 inhibition promotes neuronal differentiation in glioblastoma, a potential additional mechanism of action of MEK1/2 inhibitors. Thus, MEK inhibitors could be efficacious in glioblastoma patients with activated EGFR/MAPK signaling.

Tourist Landscape Preferences in a Historic Block Based on Spatiotemporal Big Data-A Case Study of Fuzhou, China

Historic blocks are valuable architectural and landscape heritage, and it is important to explore the distribution characteristics of tourists to historic blocks and their landscape preferences to realize the scientific construction and conservation of historic blocks and promote their sustainable development. At present, few studies combine the analysis of tourist distribution characteristics with landscape preferences. This study takes the historic block of Three Lanes and Seven Alleys in Fuzhou as an example, combines field research and questionnaires to construct a landscape preference evaluation indicator system for the historic block, measures the distribution characteristics of tourists in the block through the heat value of tourist flow obtained from the Tencent regional heat map, and analyses the influence of landscape preference indicators on the heat value of tourist flow in the block through stepwise multiple linear regression. The research shows that: (1) the spatial and temporal variation in the heat value of tourist flow tends to be consistent throughout the block, from 7 a.m. to 6 p.m., showing a "rising, slightly fluctuating and then stabilizing" state, both on weekdays and on weekends. (2) The factors influencing the heat value of tourist flow in the different spatial samples are various, with commercial atmosphere, plant landscape, accessibility of the road space, architecture, and the surrounding environment having a significant impact on the heat value of tourist flow. Based on the analysis of the landscape preferences of tourists in the historic block, a landscape optimization strategy is proposed to provide a reference for the management and construction of the block.

[Clinical efficacy and safety of endobronchial one-way valves for the treatment of bronchopleural fistula]

Objective: To investigate the efficacy and safety of interventional endobronchial one-way valves (EBV) for the treatment of peripheral bronchopleural fistula (BPF). Methods: A total of 33 patients with peripheral BPF who underwent EBV implantation in Endoscopy Center of Shanghai Pulmonary Hospital from August 2017 to December 2021 were selected as the research objects. All the patients were diagnosed with peripheral BPF before the implantation surgery. The detailed medical records of the patients were collected, and the etiology, lesion location, treatment method and operation process, treatment efficacy and postoperative complications were analyzed to evaluate the efficacy and safety of EBV implantation. Results: Of the 33 patients in our study, 26 were male and 7 were female. The median age was 54.7 (28-86) years. There were 18 cases of BPF after thoracic surgery (54.5%), 6 cases of chronic obstructive pulmonary disease complicated with spontaneous pneumothorax (18.2%), and 12 cases of pulmonary tuberculosis and non-tuberculous mycobacterial infection with spontaneous pneumothorax (36.4%). A total of 63 valves were inserted in the 33 cases, and a maximum of valves and at least one were inserted in a single case. The lesions were located in the right lower lobe in 16 cases (48.5%) and the left upper lobe in 12 cases (36.4%). Of the 33 patients undergoing EBV placement, 22 (66.7%) were successful, with chest drainage tube indwelling duration of (88.5±36.6) days and (29.6±11.4) days, respectively, before and after EBV treatment. The time from EBV placement to successful withdrawal of EBV was (102.2±31.3) days. During a postoperative follow-up of 6 months after EBV treatment, the main complications were 29 cases with attachment of secretions to the EBV (90.6%) and 13 cases (40.6%) with mild granulation proliferation. In addition, there were five patients with moderate to severe granulation proliferation (15.6%), one with valve displacement or shedding (3.1%), and one with bleeding (3.1%). Conclusions: In this study, the success rate of EBV placement and occlusion was 66.7%. Transbronchoscopic EBV placement in the treatment of peripheral BPF is a effective treatment with relatively minor complications.

Research Progress and Hotspot Evolution Analysis of Landscape Microclimate: Visual Analysis Based on CNKI and WOS

With the increasing requirements of healthy habitat environments, landscape microclimates have been widely concerned. To comprehensively grasp the development history and research status of the landscape microclimates in China and other countries, CiteSpace software was used to comparatively analyze and visually present the literature related to landscape microclimates in CNKI and WOS databases for the past 20 years. The results show that: (1) The number of publications on landscape microclimate research shows an increasing trend in China and other countries, and the number of publications increased significantly after 2016. Although the number of publications by Chinese scholars is less than that of foreign scholars, they have developed rapidly in recent years, and their international influence has increased significantly. (2) A positive exchange has been formed among international scholars, and the number of collaborative studies has been increasing. China's microclimate research has formed relatively stable teams that have conducted numerous studies in the fields of urban communities, street greening, and plant communities, respectively. Although the links between research teams and institutions in China and other countries are relatively close, they still need to be further strengthened. (3) In the past decade, the theoretical system of landscape microclimates has been improved, and the research themes have become more concentrated, but it still has remained close to the early basic research. (4) Future research will remain centered on "mitigating the urban heat island effect" and "optimizing human heat perception". New topics such as "biodiversity", "carbon cycle", and "climate change" have been added. In conclusion, the research needs to continue to explore the evaluation system of microclimates and verify the evaluation index of outdoor thermal comfort for human thermal adaptation in different regions. The standards and systems of human habitat adapted to different regional characteristics should be formed.

CNSC-12. NEURONAL DIFFERENTIATION DRIVES THE ANTI-TUMOR EFFICACY OF MEK INHIBITION IN GLIOBLASTOMA

Multiple genomic aberrations and distinct molecular subtypes of glioblastoma (GBM) have been identified through multi-omics analyses including single-cell genomic and epigenomic analysis. Epidermal Growth Factor Receptor (EGFR) amplification is found in nearly 50% of GBM tumors. Several EGFR inhibitors have been tested in GBM but failed to demonstrate long-term therapeutic benefit, presumably due to target heterogeneity, escape signal pathways, and acquired resistance. Therefore, we investigated downstream signaling, mitogen-activated protein kinase (MEK1/2) as a potential therapeutic target for GBM. We utilized an unbiased high-throughput screening with a panel of glioma stem-like cells (GSCs) and identified that GBM cells harboring EGFR amplification showed anti-proliferative and apoptotic cell death (sensitive) to multiple MEK inhibitors. RNA-seq analysis of cells pre- and post-treatment with trametinib, a potent MEK inhibitor, revealed an upregulation of neurogenesis and neuronal differentiation genes such as β-III tubulin, ASCL1, DLL1, DLL3, NeuroD4, PAX6 and NCAM1. In addition, downregulation of the several MEK targets including erythroblast transformation specific (ETS) family genes, particularly ETV5 was observed. We demonstrated that MEK inhibition increased neuronal differentiation demonstrated by immunofluorescence, western blot, and RT-qPCR experiments using selected differentiation markers (β-III tubulin, ASCL1, DLL3, and NeuroD4). In addition, ETV-5 knockout in GSCs by CRISPR/Cas-9 promoted the expression of neuronal differentiation genes. Oral treatment of trametinib in an orthotopic GSC xenograft model significantly improved animal survival, in which 25-30% of mice are long-term survivors. This was accompanied by decreased MEK/ERK signal and cell proliferation in tumor tissues. Thus, we demonstrated here that MEK1/2 inhibition by trametinib induces neuronal differentiation mediated through downregulation of ETV-5 in GBM, a potential novel mechanism of action of MEK1/2 signal inhibition.

Study on the Microclimate Effect of Water Body Layout Factors on Campus Squares

Quantifying the water layout factors in a campus square helps to lay out water bodies more scientifically and utilize the microclimate effect to alleviate the heat and humidity of campus squares in summer. The West Gate Square of Fujian Agriculture and Forestry University in China has been used as the primary theoretical model, and the landscape pattern index from landscape ecology has been used to quantify the scale, shape, and dispersion of water bodies. Consider the typical weather, the summer solstice, as the experiment time. The relationship between the water body layout factors and cooling effect, the humidification effect, and the wind speed is clarified from both temporal and spatial perspectives. The data were analyzed with ENVI-met and Arcgis software. Then, the optimum campus square water body layout mode was concluded. The results show that: (1) The scale, dispersion, and shape of the water body has a significant effect on the campus temperature and humidity, while the effect on wind speed is not significant. (2) From the cooling and humidifying effect, the ranking of the regulating ability of the water body layout factors is scale > shape > dispersion; the ranking of the influence range is shape > scale > dispersion. (3) When the boundary of the square is determined, the optimum water body layout mode is that the water body area accounts for 36% of the total square area. The shape of the water body is concentrated and not dispersed square. When the water body layout is determined, the optimum layout mode of the boundary is length:width = 1:2.

SIRT3 Promotes the Development of Esophageal Squamous Cell Carcinoma by Regulating Hexokinase 2 through the AKT Signaling Pathway

In the present study, we explored whether sirtuin-3 (SIRT3) regulates the proliferation and migration of esophageal squamous cell carcinoma (ESCC) and investigated the mechanisms underlying the oncogene role of SIRT3. siRNA was used to transfect Eca109 cells and downregulate SIRT3. The proliferation and migration of Eca109 cells were examined by the CCK-8 assay, colony formation assay, Transwell assay, and scratch test. Quantitative real-time PCR and Western blotting were used to detect SIRT3, hexokinase 2, AKT, and p-AKT in Eca109 cells. Functional assays showed that downregulation of SIRT3 could inhibit the proliferation and migration of ESCC cells. Reduced SIRT3 expression downregulated hexokinase 2 expression and inhibited AKT activation in ESCC. These results indicated that SIRT3 promote ESCC development and progression by regulating hexokinase 2 through the AKT signaling pathway. SIRT3 promote ESCC proliferation and migration by regulating HK-2 through the AKT signaling pathway.

Ultracompact topological photonic switch based on valley-vortex-enhanced high-efficiency phase shift

Topologically protected edge states based on valley photonic crystals (VPCs) have been widely studied, from theoretical verification to technical applications. However, research on integrated tuneable topological devices is still lacking. Here, we study the phase-shifting theory of topological edge modes based on a VPC structure. Benefiting from the phase vortex formed by the VPC structure, the optical path of the topological edge mode in the propagation direction is approximately two-fold that of the conventional optical mode in a strip waveguide. In experiments, we show a 1.57-fold improvement in π-phase tuning efficiency. By leveraging the high-efficiency phase-shifting properties and the sharp-turn features of the topological waveguide, we demonstrate an ultracompact 1 × 2 thermo-optic topological switch (TOTS) operating at telecommunication wavelengths. A switching power of 18.2 mW is needed with an ultracompact device footprint of 25.66 × 28.3 μm in the wavelength range of 1530-1582 nm. To the best of our knowledge, this topological photonic switch is the smallest switch of any dielectric or semiconductor 1 × 2/2 × 2 broadband optical switches, including thermo-optic and electro-optic switches. In addition, a high-speed transmission experiment employing the proposed TOTS is carried out to demonstrate the robust transmission of high-speed data. Our work reveals the phase-shifting mechanism of valley edge modes, which may enable diverse topological functional devices in many fields, such as optical communications, nanophotonics, and quantum information processing.

A Comparative Study of Bone Tissue Morphology and Bone Turnover Markers in Different Stages of Kümmell's Disease

Although the incidence of Kümmell's disease (KD) has increased significantly in recent years, its pathological mechanism is still unclear. The aim of this study is to investigate the histomorphological characteristics and the kinetics of bone turnover markers following KD. This study involves 82 patients with KD, and fasting blood samples were collected to detect the serum concentration of bone turnover markers. A transpedicular bone biopsy was performed to collect bone biopsy specimens during vertebroplasty surgery. According to Li's staging system for KD, all cases were divided into 3 stages. Comparisons of the 3 stages and their kinetics were conducted. 19 (23.2%) patients were classified as Stage I, 39 (47.5%) as Stage II, 24 (29.2%) as Stage III. Bone histomorphological analysis showed that the ratios of WBV and FV reached a peak value (14.23 ± 0.62 and 54.63% ± 3.52%; p = 0.001 and 0.001) at Stage I. The ratios of NBV remained low (4.81% ± 2.61%) in Stage I, but reached a peak value (18.50% ± 2.77%; p = 0.001) in Stage III. Bone metabolism index level showed that the serum concentration of OST and β-CTX continued to rise after fracture, reaching a peak value of (38.15 ± 3.84 and 1.31 ± 0.16 ng/Ml; p = 0.073 and 0.026), while PINP reached its valley value (48.57 ± 7.25 ng/Ml; p = 0.069) in Stage III. A significant and negative correlation was found between the ratio of β-CTX and EBV/TV (p= 0.0194, r = -0.2037), and FV/TV (p= 0.0001, r = -0.5368). At the same time, β-CTX had a positive significant correlation with the NBV/TV (p= 0.0001, r = 0.6218). Bone histomorphometric analysis and bone turnover markers showed that KD has a possibility of healing in the early stage.

Does Bird Diversity Affect Public Mental Health in Urban Mountain Parks?-A Case Study in Fuzhou City, China

Intensified urbanization has caused a linear decline in the quality of urban biodiversity and indirectly harms our current human settlement environment. Urban mountain parks provide a refuge for the animals and plants and play a vital role in satisfying residents’ lives. At present, few studies are focusing on the impact of biodiversity on human mental health benefits of urban mountain parks in high-density construction areas along the coast of the Eastern Hemisphere. Here, we examined the relationship between bird abundance, Shannon diversity, Simpson diversity, and Richness and momentary mental health (positive, negative, and anxiety) in urban mountain parks. The timed species counts method was used to conduct three surveys of birds in urban mountain parks, and linear regression was performed on the relationship between bird diversity and mental health among sites. According to the regression model results, we found no significant correlation in any disturbance levels. As urban mountain parks are an essential part of the human settlement environment, how to improve the biodiversity and mental health of urban mountain parks is one of the focuses of research on biodiversity well-being in the future. Urban planning authorities and public mental health researchers should pay attention to the importance of biodiversity in urban development and consider how to realize the beautiful vision of the harmonious coexistence of humans, animals, plants, and the environment in which we live.

Risk Factors for Poor Outcomes Following Minimally Invasive Discectomy: A Post Hoc Subgroup Analysis of 2-Year Follow-up Prospective Data

Objective

A post hoc subgroup analysis of prospectively collected data from a randomized controlled trial was conducted to identify risk factors related to poor outcomes in patients who underwent minimally invasive discectomy.

Methods

Patients were divided into satisfied and dissatisfied subgroups based on Oswestry Disability Index (ODI), visual analogue scale (VAS) back pain score (VAS-back) and leg pain score (VAS-leg) at short-term and midterm follow-up according to the patient acceptable symptom state threshold. Demographic characteristics, radiographic parameters, and clinical outcomes between the satisfied and dissatisfied subgroups were compared using univariate and multivariate analysis.

Results

A total of 222 patients (92.1%) completed 2-year follow-up, and the postoperative ODI, VAS-back, and VAS-leg were significantly improved after surgery as compared to preoperatively. Multivariate analysis indicated older age (p=0.026), lateral recess stenosis (p=0.046), and lower baseline ODI (p=0.027) were related to poor short-term functional improvement. Higher baseline VAS-back (p=0.048) was associated with poor short-term relief of back pain, while absence of decreased sensation (p=0.019) and far-lateral disc herniation (p=0.004) were associated with poorer short-term relief of leg pain. Lumbar facet joint osteoarthritis was identified as a risk factor for poor functional improvement (p=0.003) and relief of back pain (p=0.031). Disc protrusion (p=0.036) predicted poorer relief of back pain at midterm follow-up.

Conclusion

In this study, several factors were identified to be predictive of poor surgical outcomes following minimally invasive discectomy. (ClinicalTrials.gov number: NCT01997086).

Wide-angle and broadband solar absorber made using highly efficient large-area fabrication strategy

High performance and cost-effective solar absorbers are crucial for various optical applications, such as solar collection and thermophotovoltaic devices. This study designs and experimentally demonstrates a wide-angle and broadband solar absorber. The proposed absorber is composed of tapered polyimide substrate and Al-Cr-SiO₂-Cr-SiO₂ thin-film based on the optical interference of the multilayer thin film and excited magnetic resonance of light-trapping structures. The composite process of the colloidal lithography method and magnetron sputtering is employed for efficient fabrication in a large area. The average absorbance is more than 93% from 300 nm to 2500 nm and shows an angular tolerance of up to 60°. The high efficiency and large-area fabrication capability demonstrated by the proposed solar absorber presents future application potential in flexible solar collection devices.

Identification of ecological networks and nodes in Fujian province based on green and blue corridors

China's Green Space System Planning (GSSP) research has gradually expanded from central urban areas to municipal and provincial scales in recent years. Besides, the research on the role of green space in the water environment has also attracted much attention. However, the study of green corridors usually ignored hydrological data, which widespread absence especially in the large area scale. And the scale of green corridor construction mainly focused on central urban areas. This paper took China's Fujian province as an example. Based on the DEM elevation data, the article identified blue corridors without hydrological data. In addition, the green corridors were determined based on the land use data. According to the green corridors and blue corridors protection, we identified the ecological networks and nodes by the network analysis method. The results showed that the blue corridors identified by DEM data were consistent with the hydrological status quo. The regional status of the identified ecological networks and nodes were basically in line with their characteristics, proving the value of the planning methods. Finally, based on the identification results, suggestions for Fujian's ecological networks and nodes are put forward.

Difference in light use strategy in red alga between Griffithsia pacifica and Porphyridium purpureum

Phycobilisomes (PBSs) are the largest light-harvesting antenna in red algae, and feature high efficiency and rate of energy transfer even in a dim environment. To understand the influence of light on the energy transfer in PBSs, two red algae Griffithsia pacifica and Porphyridium purpureum living in different light environment were selected for this research. The energy transfer dynamics in PBSs of the two red algae were studied in time-resolved fluorescence spectroscopy in sub-picosecond resolution. The energy transfer pathways and the related transfer rates were uncovered by deconvolution of the fluorescence decay curve. Four time-components, i.e., 8 ps, 94 ps, 970 ps, and 2288 ps were recognized in the energy transfer in PBSs of G. pacifica, and 10 ps, 74 ps, 817 ps and 1292 ps in P. purpureum. In addition, comparison in energy transfer dynamics between the two red algae revealed that the energy transfer was clearly affected by lighting environment. The findings help us to understand the energy transfer mechanisms of red algae for adaptation to a natural low light environment.

Absorption Reduction of Large Purcell Enhancement Enabled by Topological State-Led Mode Coupling

We propose the mechanism of edge state-led mode coupling under topological protection; i.e., localized surface plasmons almost do not have any influence on the edge state, while the edge state greatly changes the local field distribution of surface plasmons. Based on this mechanism, in the well-designed topological photonic structure containing a resonant plasmon nanoantenna, an obvious absorption reduction in the spontaneous emission spectra appears due to the near-field deformation around the antenna induced by the edge state. Because a plasmon antenna with ultrasmall mode volume provides large Purcell enhancement and simultaneously the photonic crystal guides almost all scattering light into its edge state, the rate of nonscattering single photons reaches more than 10^{4}γ_{0}. This topological state-led mode coupling mechanism and induced absorption reduction, which are based on topological protection, will have a profound effect on the study of composite topological photonic structures and related micro- and nanoscale cavity quantum electrodynamics. Also, nonscattering large Purcell enhancement will provide practical use for on-chip quantum light sources, such as single-photon sources and nanolasers.

Moiré Fringe Induced Gauge Field in Photonics

We realize moiré fringe induced gauge field in a double-layer photonic honeycomb metacrystal with mismatched lattice constants. Benefitting from the generated strong effective gauge field, we report direct measurement of the band diagrams of both Landau level flat bands and intermagnetic-domain edge states. Importantly, we observe the correlation between the momentum and orbital position of the Landau modes, serving as an evidence of the noncommuteness between orthogonal components of the momentum. Without complicated time driving mechanics and careful site-by-site engineering, moiré superlattices could emerge as a powerful means to generate effective gauge fields for photonics benefiting from its simplicity and reconfigurability, which can be applied to nonlinearity enhancement and lasing applications at optical frequencies.

Depletion of CLK2 sensitizes glioma stem-like cells to PI3K/mTOR and FGFR inhibitors

The Cdc2-like kinases (CLKs) regulate RNA splicing and have been shown to suppress cell growth. Knockdown of CLK2 was found to block glioma stem-like cell (GSC) growth in vivo through the AKT/FOXO3a/p27 pathway without activating mTOR and MAPK signaling, suggesting that these pathways mediate resistance to CLK2 inhibition. We identified CLK2 binding partners using immunoprecipitation assays and confirmed their interactions in vitro in GSCs. We then tested the cellular viability of several signaling inhibitors in parental and CLK2 knockdown GSCs. Our results demonstrate that CLK2 binds to 14-3-3τ isoform and prevents its ubiquitination in GSCs. Stable CLK2 knockdown increased PP2A activity and activated PI3K signaling. Treatment with a PI3K/mTOR inhibitor in CLK2 knockdown cells led to a modest reduction in cell viability compared to drug treatment alone at a lower dose. However, FGFR inhibitor in CLK2 knockdown cells led to a decrease in cell viability and increased apoptosis. Reduced expression of CLK2 in glioblastoma, in combination with FGFR inhibitors, led to synergistic apoptosis induction and cell cycle arrest compared to blockade or either kinase alone.

Percutaneous transforaminal full endoscopic decompression for the treatment of lumbar spinal stenosis

Background

One advantage of an endoscopic approach to treating lumbar spinal stenosis is preservation of spine stability and the adjacent anatomy, and there is a decrease in adjacent segment disc degeneration. The purpose of this study was to discuss the clinical efficacy of percutaneous transforaminal endoscopic decompression for the treatment of lumbar spinal stenosis (LSS).

Methods

This is a retrospective study. From September 2012 to June 2017, 45 patients who were diagnosed with LSS underwent the treatment of percutaneous transforaminal endoscopic decompression (PTED) and were followed up at 1 week, 3 months and 1 year postoperatively. Low back pain and leg pain were measured by Visual Analogue Scale scoring methods (VAS-back and VAS-leg), while functional outcomes were assessed by using the Oswestry Disability Index (ODI). All patients had one-level lumbar spinal stenosis.

Results

The most common type of stenosis was lateral recess stenosis (n = 22; 48.9%), followed by central stenosis (n = 13; 28.9%) and foraminal stenosis (n = 10: 22.2%). Regarding comparisons of VAS-back, VAS-leg, and ODI scores before and after operation, VAS and ODI scores significantly improved. The average leg VAS score improved from 7.01 ± 0.84 to 2.28 ± 1.43 (P < 0.001). The average ODI improved from 46.18 ± 10.11 to 14.40 ± 9.59 (P < 0.001). We also examined changes in ODI and VAS scores from baseline according to types of spinal stenosis, stenosis grade, spinal instability, and revision surgery in the same segment. The improvement percentage of leg VAS score was significantly less in patients with severe stenosis at both 3 months and 1 year postoperatively. The improvement percentages of ODI and leg VAS scores were significantly less in patients who had spinal instability and patients who had undergone revision surgery.

Conclusion

The PTED approach seems to give good results for the treatment of LSS. However, this approach may be less effective for LSS patients who have lumbar instability or require revision surgery in the same segment.

Five-photon absorption upconversion lasing from on-chip whispering gallery mode

In the progress of ultrafast optics, nonlinear interactions between light and matter are very important in scientific and technical fields. In particular, the high-order nonlinear effect induced by multi-photon absorption (MPA) upconversion lasing has injected new impetus into the research on short-wavelength laser sources. Here, we report the realization of amplified spontaneous emission (ASE) by MPA simultaneously in an epitaxy thin film. In addition, by virtue of the excellent optical confinement of cylindrical microcavities with high Q (∼4 × 103) on-chip, we demonstrated, for the first time, low-threshold upconversion lasing of five-photon absorption enhanced by a microcavity at room temperature. The resonant whispering-gallery mode (WGM) distribution in cylindrical microcavities was simulated comprehensively by the finite difference time domain (FDTD) method. We found that the high-order nonlinear optical process could be significantly enhanced in the microcavity with an increase in the lifetime of radiation photons.

The genome sequence of star fruit (Averrhoa carambola)

Oxalidaceae is one of the most important plant families in horticulture, and its key commercially relevant genus, Averrhoa, has diverse growth habits and fruit types. Here, we describe the assembly of a high-quality chromosome-scale genome sequence for Averrhoa carambola (star fruit). Ks distribution analysis showed that A. carambola underwent a whole-genome triplication event, i.e., the gamma event shared by most eudicots. Comparisons between A. carambola and other angiosperms also permitted the generation of Oxalidaceae gene annotations. We identified unique gene families and analyzed gene family expansion and contraction. This analysis revealed significant changes in MADS-box gene family content, which might be related to the cauliflory of A. carambola. In addition, we identified and analyzed a total of 204 nucleotide-binding site, leucine-rich repeat receptor (NLR) genes and 58 WRKY genes in the genome, which may be related to the defense response. Our results provide insights into the origin, evolution and diversification of star fruit.

A meta-analysis of serum osteocalcin level in postmenopausal osteoporotic women compared to controls

Background

Circulatory osteocalcin (OC) has been widely used as a biomarker to indicate bone turnover status in postmenopausal osteoporosis (PMO). However, the change of serum OC (sOC) level in PMO cases compared to postmenopausal controls remains controversial.

Methods

We searched the online database of PubMed and Cochrane Library. A meta-analysis of case-control studies was performed to compare the pooled sOC level between PMO patients and postmenopausal controls. Subgroup analysis according to potential confounding factors (different OC molecules and regions of the study population) was also performed.

Results

Ten case-control studies with 1577 postmenopausal women were included in this meta analysis. We found no significant difference in the pooled sOC level [mean difference (MD) = 1.84, 95% confidence interval (CI): (− 1.49, 5.16), p = 0.28] between PMO patients and controls. Subgroup analysis also revealed no significant difference in intact OC [MD = 1.76, 95%CI: (− 1.71, 5.23), p = 0.32] or N-terminal mid-fragment of the OC molecule [MD = 0.67, 95%(− 5.83, 7.18), p = 0.84] between groups. For different regions, no significant difference in sOC was found in Asian population between cases and controls [MD = -0.06, 95%(− 6.02, 5.89), p = 0.98], while the pooled sOC level was significantly higher in European PMO cases than controls [MD = 3.15, 95%(0.90, 5.39), p = 0.006].

Conclusions

Our analysis revealed no significant difference in sOC level between PMO cases and controls according to all the current eligible studies. OC molecules are quite heterogeneous in the circulation and can be influenced by glucose metabolism. Therefore, sOC is currently not a good indicator for the high bone turnover status in PMO. More trials with standardized methodologies for the evaluation of circulatory OC are awaited to update our current findings.

DDIS-32. MEK INHIBITORS INDUCES NEURONAL DIFFERENTIATION IN EGFR AMPLIFIED GLIOMA STEM LIKE CELLS

The median survival for patients with glioblastoma (GBM) is 12–15 months highlighting the need for better therapeutic strategies for this deadly disease. Genomic and epigenomic sequencing analysis at the single cell level have identified multiple genomic aberrations as potential targets for therapeutic intervention in GBM. EGFR and PDGFR amplification are evident in nearly 40% and 12% of human GBM, respectively. Although the first and second-generation EGFR tyrosine kinase small molecule inhibitors failed to show long term therapeutic benefit in GBM patients, multiple factors such as incorrect patient selection, acquired resistance, and drug-target heterogeneity may all lead to clinical failure of targeted therapies. Although the multilevel genomic characterization of gliomas are increasing, the clinical translation of these findings is beginning to unravel. In this study, we attempted to correlate the genomic variations using an unbiased high throughput drug screen using primary glioma stem-like cell (GSCs) as our model system. An unbiased high-throughput screen utilizing our GSC models identified that glioblastoma cells harboring focal EGFR amplification are sensitive to mitogen-activated protein kinase (MEK) inhibitors. MEK inhibition induced apoptosis in EGFR amplified cells at low concentration. RNA sequence analysis of cells treated with MEK inhibitors revealed upregulation of genes related to neuronal differentiation and down regulation of MEK target genes in MEK sensitive glioma stem cells. Additionally, RNA sequencing of GSCs with acquired MEK inhibitor resistance demonstrated an upregulation of oncogenic transcription factor ETS Variant Gene 1 (ETV1) as a mediator of resistance. Overall our data suggest that the MEK inhibition in combination with ETV inhibitors could be a potential therapeutic target for a subset of GBM patients.

Nanoassembly and Multiscale Computation of Multifunctional Optical-Magnetic Nanoprobes for Tumor-Targeted Theranostics

Gold nanorods, mesoporous silica, gadolinia, folic acid, and polyethylene glycol (PEG) derivatives have been investigated due to their own advantages in cancer theranostics. However, it remains a great challenge to assemble these components into a stable unity with the diverse and enhanced functionality for more potential applications. Herein, as inspired by the first-principles calculation, a highly stable and safe all-in-one nanoprobe is fabricated via a novel nanoassembly strategy. Multiscale calculations were performed to address the atomistic bonding of a nanoprobe, heat necrosis of a tumor adjacent to the vasculature, and thermal diffusion in a photothermal circumstance, respectively. The nanoprobe gains an 8-fold increase in magnetic resonance imaging (MRI) relaxivity compared to the clinical gadolinium diethylenetriaminepentaacetate, achieving a significant MRI signal in vivo. Conjugated with folate-PEG, the nanoprobe can be effectively absorbed by tumoral cells, obtaining a vivid two-photon cell imaging. A specific multisite scheme for photothermal therapy of a solid tumor is proposed to improve low photothermal efficacy caused by thermal diffusion in a large tumor, leading to the successful cure of the mice with xenograft tumor sized 10-12 mm. In vitro and in vivo toxicity, long-term excretion data, and the recovery of the treated mice demonstrate that the theranostic nanoprobe possesses good biocompatibility and metabolism efficacy.

Chitosan/hydroxyapatite modified carbon/carbon composites: synthesis, characterization and in vitro biocompatibility evaluation

Carbon/carbon composite (C/C), due to its bio-inert property, is prone to cause bone consolidation defects and bacterial infections in clinical applications. Therefore, there is a great demand in practical applications to prevent implant infections and enhance its bone consolidation capability. In this study, we have developed a facile approach to construct a chitosan/hydroxyapatite composite modified layer on C/C surface by electrochemical deposition and a covalent grafting technique, and the modified layer has both the antibacterial activity of chitosan (CS) and the bioactivity of hydroxyapatite (HAP). The microstructure and chemical composition of the modified layer were analyzed using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and water contact angle measurements. The biological properties of the composites were evaluated using cell culture, antimicrobial test and real-time quantitative PCR in vitro. The results showed that the CS/HAP modified C/C exhibited excellent biocompatibility, bacteriostasis and osteoinductive ability. These properties are beneficial for the potential application of the modified C/C composite as a bone tissue replacement material.

Carbon/carbon composite (C/C), due to its bio-inert property, is prone to cause bone consolidation defects and bacterial infections in clinical applications.

[Comparative study of microendoscope-assisted and conventional minimally invasive transforaminal lumbar interbody fusion for degenerative lumbar diseases]

Objective

To analyze the medium and long-term effectiveness of microendoscope-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar degenerative diseases in comparison with conventional tubular retractor-assisted MIS-TLIF.

Methods

Between November 2008 and March 2013, 53 patients with single segment lumbar degenerative diseases were enrolled. According to the different working channel performed, 28 patients were treated by microendoscope-assisted MIS-TLIF (observation group), while the remaining cases received conventional tubular retractor-assisted MIS-TLIF via Wiltse approach (control group). Preoperative baseline data, including age, gender, body mass index, disease etiology, operated level, the ration for requiring bilateral canal decompression, and preoperative visual analogue scale (VAS) socre of low back pain and leg pain, Japanese Orthopedic Association (JOA) score, Oswestry disability index (ODI) score, showed no significant difference between the two groups ( P>0.05). The operation time, intraoperative blood loss, intraoperative fluoroscopy time, postoperative analgesic drug dose, postoperation in-bed time, and perioperative complication incidence were recorded respectively and compared between the two groups. Radiographic evaluation of interbody fusion was performed based on Bridwell grading system at 2 years after operation. VAS scores of low back pain and leg pain, JOA score, and ODI score were assessed before operation, at 2 years after operation, and at last follow-up respectively. Surgical outcome satisfaction was assessed by modified MacNab criteria at last follow-up.

Results

When compared with those in control group, both intraoperative blood loss and postoperative analgesic drug dose were significantly decreased in observation group ( P<0.05); similarly, the operation time and intraoperative fluoroscopy time were also significantly increased in observation group ( P<0.05). There was no significant difference of postoperative in-bed time between the two groups ( t=-0.812, P=0.420). Both groups were followed up 6-10.3 years, with an average of 7.9 years. Regarding perioperative complication, its incidence was 14.3% and 20.0% in observation group and control group, respectively, showing no significant difference between both groups ( χ ²=0.306, P=0.580). Specifically, there were intraspinal hematoma formation in 1 case, incision infection in 1 case, urinary infection in 1 case, transient delirium in 1 case in observation group. By contrast, there were dural tear and cerebrospinal fluid leakage in 1 case, urinary infection in 1 case, pneumonia in 1 case, transient delirium in 2 cases in control group. Bridwell criterion was used to judge the intervertebral fusion at 2 years after operation, the fusion rates of observation group and control group were 92.9% and 92.0%, respectively, showing no significant difference ( χ ²=0.162, P=0.687). At both 2-year postoperatively and last follow-up, the VAS scores of low back pain and leg pain, JOA score, and ODI score were significantly improved when compared with those before operation ( P<0.01), whereas no significant difference between the two groups at either time point was found ( P>0.05). At last follow-up, the results of patients' satisfaction with surgery evaluated by modified MacNab criteria, and the excellent and good rates of the observation group and the control group were 96.4% and 92.0%, respectively, showing no significant difference ( χ ²=0.485, P=0.486).

Conclusion

The medium and long-term effectiveness of microendoscope-assisted MIS-TLIF are similar to those of conventional tubular retractor-assisted MIS-TLIF for lumbar degenerative diseases. The former operation has the additional advantages in terms of more clear surgical site visually, less intraoperative blood loss, and reduced postoperative analgesic dose, all of which seem more feasible to clinical teaching.

Abstract 4678: Targeting MEK in EGFR amplified glioma stem like cells induces differentiation

The median survival for patients with recurrent glioblastoma is nine to twelve months highlighting the need for better therapeutic strategies for this deadly disease. The revolution in cancer genomics has identified multiple amplification events as potential targets for therapeutic intervention in many cancers including glioblastoma. Multiple factors such as incorrect patient selection, inadequate drug delivery across the blood brain barrier, acquired resistance and drug-target heterogeneity may all lead to clinical failure of targeted therapies. Receptor tyrosine kinase (RTK) signaling mediated by EGFR and PDGFR account for the core RTK signaling alterations in glioblastoma. EGFR-amplification (in ~40%) and PDGFR amplification (in ~12%) are detected in receptor tyrosine kinase- dysregulated glioblastoma. The first generation or second-generation EGFR tyrosine kinase small molecule inhibitors failed to show long term therapeutic benefit in glioblastoma patients. Through an unbiased high-throughput screen utilizing our glioma stem-like cells (GSCs) we identified that glioblastoma cells harboring EGFR amplification are uniquely vulnerable to mitogen-activated protein kinase (MEK) inhibitors. MEK inhibition induces apoptosis in EGFR amplified cells at low concentration. Furthermore, RNA sequence analysis of MEK inhibition revealed upregulation of genes related to differentiation in MEK sensitive glioma stem cells. Based upon these in vitro studies we are currently investigating MEK inhibition in a GBM xenograft mouse model. Overall our data suggest that the MEK inhibition could be a potential therapeutic target in a selective group of glioblastoma patients.

Note: This abstract was not presented at the meeting.

Citation Format: Soon Young Park, Yuji Piao, Emmanuel Martinez-Ledesma, Jianwen Dong, Sabbir Khan, Sandeep Mittal, Ze-yan Zhang, Erik P. Sulman, Veerakumar Balasubramaniyan, John F. de Groot. Targeting MEK in EGFR amplified glioma stem like cells induces differentiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4678.

Therapeutic Effects and Safety of Percutaneous Disc Decompression with Coblation Nucleoplasty in Cervical Vertigo: A Retrospective Outcome Study with 74 Consecutive Patients and Minimum 1-Year Follow-Up

BACKGROUND

Surgical treatment of cervical vertigo has been rarely reported. This is the first retrospective study to evaluate the clinical outcomes of percutaneous disc decompression with coblation nucleoplasty (PDCN) for treatment of cervical vertigo.

OBJECTIVES

To assess the clinical outcomes of patients with cervical vertigo who failed to improve with conservative care and who were subsequently treated with PDCN.

STUDY DESIGN

This study used a retrospective design.

SETTING

The research was conducted within an interventional vertigo management and spine practice.

METHODS

Seventy-four consecutive patients with cervical vertigo underwent PDCN and were followed for at least one year. Outcome measures included the dizziness intensity Visual Analog Scale (VAS), dizziness frequency, the Dizziness Handicap Inventory (DHI), and neck pain intensity. Clinical efficacy was assessed by rating scale and the modified MacNab evaluation criteria. Surgical complications during the operation and follow-up were also recorded.

RESULTS

The vertigo VAS score, frequency of dizziness, DHI, and neck pain intensity were all decreased significantly from evaluation before surgery to one week after surgery and to the last follow-up, giving a mean effective rate of 94.6% one week after surgery and 90.6% at the last follow-up. Good to excellent results were attained in 85.1% of these patients one week after PDCN and in 75.7% of the sufferers at the last follow-up (P < 0.001). There were 5 patients with transient adverse effects (6.25%) reported within the first month after surgery; they all recovered after conservative treatment. No neurological complications were found and no patient went on to spinal fusion surgery thereafter.

LIMITATIONS

The rate of follow-up was 70% and a placebo effect cannot be excluded. There is no gold standard for the diagnosis and treatment of cervical vertigo so far.

CONCLUSION

The clinical outcomes of PDCN for cervical vertigo were satisfactory in both the early and late postoperative period. PDCN is an effective, low-complication, minimally invasive procedure used to treat cervical vertigo. Further prospective randomized controlled trials are essential to verify this conclusion.

KEY WORDS

Cervical vertigo, percutaneous disc decompression, coblation nucleoplasty, long-term outcome, dizziness intensity, dizziness frequency, dizziness handicap inventory, clinical efficacy, surgical complication, retrospective study.

Spatial and Temporal Variations of Six Criteria Air Pollutants in Fujian Province, China

Air pollution has become a critical issue in the urban areas of southeastern China in recent years. A complete understanding of the tempo-spatial characteristics of air pollution can help the public and governmental bodies manage their lives and work better. In this study, data for six criteria air pollutants (including particulate matter (PM_2.5, PM₁₀), carbon monoxide (CO), sulfur dioxide (SO₂), nitrogen dioxide (NO₂) and ozone (O₃)) from 37 sites in nine major cities within Fujian Province, China were collected between January 2015 to December 2016, and analyzed. We analyzed the spatial and temporal variations of these six criteria pollutants, as well as the attainment rates, and identified what were the major pollutants. Our results show that: (1) the two-year mean values of PM_2.5 and PM₁₀ exceeded the Chinese National Ambient Air Quality Standard (CAAQS) standard I levels, whereas other air pollutants were below the CAAQS standard I; (2) the six criteria air pollutants show spatial variations (i.e. most air pollutants were higher in the city center areas, followed by suburban areas and exurban areas, except for O₃; and the concentrations of PM₁₀, PM_2.5, NO₂, O₃ were higher in coastal cities than in inland cities); (3) seasonal variations and the no attainment rates of air pollutants were found to be higher in cold seasons and lower in warm seasons, except for O₃; (4) the most frequently present air pollutant was PM₁₀, with PM_2.5 and O₃ being the second and third most frequent, respectively; (5) all the air pollutants, except O₃, showed positive correlations with each other. These results provide additional information for the effective control of air pollution in the province of Fujian.

Long-Term Atmospheric Visibility Trends and Their Relations to Socioeconomic Factors in Xiamen City, China

Atmospheric visibility (AV), one of the most concerning environmental issues, has shown a continuous decline in China’s urban areas, especially in Southeastern China. Existing studies have shown that AV is affected by air pollutants and climate change, which are always caused by human activities that are linked to socioeconomic factors, such as urban size, residents’ activities, industrial activities, and urban greening. However, the contribution of socioeconomic factors to AV is still not well understood, especially from a long-term perspective, which sometimes leads to ineffective policies. In this study, we used the structural equation model (SEM) in order to quantify the contribution of socioeconomic factors on AV change in Xiamen City, China, between 1987–2016. The results showed that the annual average AV of Xiamen between 1987–2016 was 12.00 km, with a change rate of −0.315 km/year. Urban size, industrial activities, and residents’ activities were found to have a negative impact on AV, while the impact of urban greening on the AV was modest. Among all of the indicators, the number of resident’s vehicles, total retail sales of consumer goods, and household electricity consumption were found to have the highest negative direct impact on the AV. The resident population, urban built-up area, and secondary industry gross domestic product (GDP) were the most important indirect impact factors. Based on our results, we evaluated the existing environmental regulations and policies of Xiamen City.

Accurate self-calibrated fiber transfer delay measurement

An accurate self-calibrated fiber transfer delay measurement method is demonstrated. Using the simplified self-calibration configuration, the measurement uncertainty of fiber transfer delay is improved. To demonstrate the accuracy of the method, the measurement results of two systems are compared. It shows that this method achieves a sub-picosecond accuracy. Besides, the chromatic dispersion of fiber under test is also obtained, which is in agreement with the nominal value.

Abstract 4858: Efficacy of the protein arginine methyltransferase PRMT5 inhibitor GSK591 in glioma stem-like cells

Protein arginine methyltransferase (PRMTs) function as epigenetic regulators of transcription and play a major role in gene regulation. PRMTs are upregulated in gastric, colorectal and lung cancer, and lymphoma and leukemia. PRMT5 is capable of forming symmetric dimethylarginine (SDMA) residues, and has been reported as a therapeutic target in glioblastoma, as its expression has been correlated with tumor grade and progression. In this study, the in vitro therapeutic efficacy of PRMT5 inhibitor GSK591 was investigated in a panel of gliomas stem-like cell (GSC) lines with specific molecular subtypes. Genomic, proteiomic (reverse protein lysate array, RPPA), methylation status and GSC subtype were correlated with drug IC50 to find predictors of drug sensitivity. The efficacy of inhibiting PRMT5 activity was retained at low dose of GSK591 in a small number of GSCs. Western blotting data showed high expression of PRMT5 and multiple bands of SDMAs in most GSCs tested (n=31), indicating PRMT5 enzymatic activity in GSC cell lines. Evidence of PRMT5 inhibition was demonstrated at low doses (&lt; 1.5 uM) in 4 GSC lines (13%) as shown by the total inhibition of SDMA expression in a dose- and time-dependent fashion after GSK591 treatment. The sensitivity of GSK591 correlated with low methylation of multiple genes pretreatment, including MAGI2, EGR2, and DUSP16. In addition, upregulated genes in sensitive GSCs correlated with proliferation signatures using gene set enrichment analyses (GSEA). Together, our study demonstrated that inhibition of PRMT5 activity and its substrate product SDMA correlated with inhibition of tumor growth. These promising in vitro results have led to ongoing experiments to evaluate the efficacy of GSK591 in intracranial xenograft models and the underlying mechanism of sensitivity and resistance to PRMT5 inhibition.

Citation Format: Vikram Shaw, Yuji Piao, Soon Young Park, Jianwen Dong, Emmanuel Martinez-Ledesma, Caroline Carrillo, Verlene Henry, Ravesanker Ezhilarasan, Erik Sulman, Veerakumar Balasubramaniyan, John F. de Groot. Efficacy of the protein arginine methyltransferase PRMT5 inhibitor GSK591 in glioma stem-like cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4858.

Abstract 4819: High-throughput screening of glioma stem-like cells (GSCs) identifies synergistic therapeutic combination of FGFR inhibitor and CDK4/6 inhibitor

High-grade gliomas are challenging tumors to treat. The lack of efficacy of single-agent therapy emphasizes the importance of developing combination strategies to overcome acquired resistance. Quantitative high-throughput screening (HTS) of 2 and 3 drug combinations at 5 concentrations (maximal concentration of 1 uM) of each agent were evaluated in a panel of GSCs to identify potentially novel combination therapy. Genomic, proteiomic (reverse protein lysate array, RPPA) and GSC subtype were correlated with drug IC50 to find biomarkers of drug sensitivity. GSCs were classified as sensitive (IC50 ≤ 1µM) or resistant (IC50 &gt;1µM) for single-agent screening. The Bliss independence model and combination index (CI) criteria were used to quantify the synergy of compound combinations. Evaluation of drug combination data for synergistic combination identified FGFR inhibitor LY2874455 and CDK4/6 inhibitor LY2835219 as the most effective combinations for multiple drug sets. Abnormal activation of FGFR and alterations in the CDKN2A-CDK4/6-Retinoblastoma 1 (RB1) pathway have been implicated in glioblastoma pathogenesis. We further investigated the in vitro combination efficacy of FGFR inhibitor and CDK4/6 inhibitor. Compared to single agent, combination of FGFR inhibitor and CDK4/6 inhibitor induced prominent cleaved poly ADP ribose polymerase (c-PARP), an index of apoptosis, which was further confirmed by Annexin V staining. Combination therapy significantly inhibited p-RB, p-STAT3, p-Akt, p-Erk and p-c-Jun expression compared to single agent. Genomic data demonstrated that high PDGFRα expression and low methylation correlated to sensitivity to the FGFR and CDK4/6 inhibitor combination. These findings were validated by demonstrating that this synergistic sensitivity was decreased by knocking out PDGFRα by CRISP/Cas9 system with the combination index (CI) at IC50 increased from 0.964 to 2.247. In addition, Western blotting showed that expression of PDGFRα and Notch1 was significantly inhibited by combination treatment. However, this combination failed to show any survival and tumor inhibition benefits in intracranial xenograft mouse models.

Citation Format: Jianwen Dong, Emmanuel Martinez-Ledesma, Nghi Nguyen, Shaofang Wu, Yuji Piao, Ningyi Tiao, Soon Young Park, David Brunell, Clifford Stephan, Roel Verhaak, Erik Sulman, Veerakumar Balasubramaniyan, John F. de Groot. High-throughput screening of glioma stem-like cells (GSCs) identifies synergistic therapeutic combination of FGFR inhibitor and CDK4/6 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4819.

Abstract 2945: Arsenic trioxide sensitizes glioma stem cells to brain penetrant PI3K and mTOR inhibitor GDC-0084

Glioblastoma is the most aggressive primary malignant brain tumor with few effective therapies. The current study evaluated arsenic trioxide (As2O3, ATO), a small-molecular agent that inhibits tumor growth via promoting promyelocytic leukemia protein (PML) degradation, in combination with multiple PI3K/mTOR inhibitors using high-throughput screening (HTS) to validate if ATO reverses glioblastoma resistance to PI3K/mTOR-targeted therapy. Quantitative single-agent and 2-drug combinations (5 drug doses, maximal concentration of 1 uM of each agent) were evaluated in 20 patient-derived glioma stem-like cells (GSCs). ATO was applied as an “anchor” drug and several mTOR and EGFR inhibitors as “probe” drugs to explore potential combination efficacy. Data from single-agent screening demonstrated that brain penetrant PI3K/mTOR inhibitor GDC-0084 potently inhibited cell viability with an IC50 ranging from 0.12μM to 5.78μM under normoxic conditions. Under hypoxic conditions, 10 of the 16 GSC cell lines remained sensitive, indicating less efficacy of GDC-0084 in the setting of a hypoxic microenvironment. Evaluation of drug combinations identified ATO and GDC-0084 as the most effective combination in vitro. ATO was synergistic with GDC-0084 in several GSCs resistant to GDC-0084 monotherapy. GSC sensitivity to GDC-0084 as single agent and in combination correlated with apoptosis, angiogenesis and PI3K/Akt pathways using gene set enrichment analyses (GSEA). In vitro combination treatment significantly inhibited PML, p-S6, p-AKT and p-mTOR expressions compared to single agent. In an orthotopic mouse model of glioma, targeting PI3K/mTOR with GDC-0084 prolonged the median survival to 81 days compared to 69 days in the control group. The efficacy of combining ATO and GDC-0084 in an orthotopic GSC mouse model is ongoing. Our studies confirm prior work demonstrating the efficacy of combining GDC-0084 with ATO, which now requires clinical validation.

Citation Format: Jianwen Dong, Emmanuel Martinez-Ledesma, Nghi Nguyen, Caroline Carrillo, Yuji Piao, Verlene Henry, Soon Young Park, Ningyi Tiao, Clifford Stephan, Roel Verhaak, Erik Sulman, Veerakumar Balasubramaniyan, John F. de Groot. Arsenic trioxide sensitizes glioma stem cells to brain penetrant PI3K and mTOR inhibitor GDC-0084 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2945.

High-Performance Ultrathin Active Chiral Metamaterials

Ultrathin active chiral metamaterials with dynamically tunable and responsive optical chirality enable new optical sensors, modulators, and switches. Herein, we develop ultrathin active chiral metamaterials of highly tunable chiroptical responses by inducing tunable near-field coupling in the metamaterials and exploit the metamaterials as ultrasensitive sensors to detect trace amounts of solvent impurities. To demonstrate the active chiral metamaterials mediated by tunable near-field coupling, we design moiré chiral metamaterials (MCMs) as model metamaterials, which consist of two layers of identical Au nanohole arrays stacked upon one another in moiré patterns with a dielectric spacer layer between the Au layers. Our simulations, analytical fittings, and experiments reveal that spacer-dependent near-field coupling exists in the MCMs, which significantly enhances the spectral shift and line shape change of the circular dichroism (CD) spectra of the MCMs. Furthermore, we use a silk fibroin thin film as the spacer layer in the MCM. With the solvent-controllable swelling of the silk fibroin thin films, we demonstrate actively tunable near-field coupling and chiroptical responses of the silk-MCMs. Impressively, we have achieved the spectral shift over a wavelength range that is more than one full width at half-maximum and the sign inversion of the CD spectra in a single ultrathin (1/5 of wavelength in thickness) MCM. Finally, we apply the silk-MCMs as ultrasensitive sensors to detect trace amounts of solvent impurities down to 200 ppm, corresponding to an ultrahigh sensitivity of >10⁵ nm/refractive index unit (RIU) and a figure of merit of 10⁵/RIU.

The polo-like kinase 1 inhibitor volasertib synergistically increases radiation efficacy in glioma stem cells

Background

Despite the availability of hundreds of cancer drugs, there is insufficient data on the efficacy of these drugs on the extremely heterogeneous tumor cell populations of glioblastoma (GBM).

Results

The PKIS of 357 compounds was initially evaluated in 15 different GSC lines which then led to a more focused screening of the 21 most highly active compounds in 11 unique GSC lines using HTS screening for cell viability. We further validated the HTS result with the second-generation PLK1 inhibitor volasertib as a single agent and in combination with ionizing radiation (IR). In vitro studies showed that volasertib inhibited cell viability, and high levels of the anti-apoptotic protein Bcl-xL expression were highly correlated with volasertib resistance. Volasertib sensitized GSCs to radiation therapy by enhancing G2/M arrest and by inducing apoptosis. Colony-formation assay demonstrated that volasertib plus IR synergistically inhibited colony formation. In intracranial xenograft mouse models, the combination of volasertib and radiation significantly inhibited GSC tumor growth and prolonged median survival compared with radiation treatment alone due to inhibition of cell proliferation, enhancement of DNA damage, and induction of apoptosis.

Conclusions

Our results reinforce the potential therapeutic efficacy of volasertib in combination with radiation for the treatment of GBM.

Methods

We used high-throughput screening (HTS) to identify drugs, out of 357 compounds in the published Protein Kinase Inhibitor Set, with the greatest efficacy against a panel of glioma stem cells (GSCs), which are representative of the classic cancer genome atlas (TCGA) molecular subtypes.

Percutaneous transforaminal endoscopic discectomy compared with microendoscopic discectomy for lumbar disc herniation: 1-year results of an ongoing randomized controlled trial

OBJECTIVE A prospective randomized controlled study was conducted to clarify whether percutaneous transforaminal endoscopic discectomy (PTED) results in better clinical outcomes and less surgical trauma than microendoscopic discectomy (MED). METHODS In this single-center, open-label, randomized controlled trial, patients were included if they had persistent signs and symptoms of radiculopathy with corresponding imaging-confirmed lumbar disc herniation. Patients were randomly allocated to the PTED or the MED group by computer-generated randomization codes. The primary outcome was the Oswestry Disability Index (ODI) score 1 year after surgery. Secondary outcomes included scores of the Medical Outcomes Study 36-Item Short-Form Health Survey bodily pain and physical function scales, EuroQol Group's EQ-5D , and the visual analog scales for back pain and leg pain. Data including duration of operation, in-bed time, length of hospital stay, surgical cost and total hospital cost, complications, and reoperations were recorded. RESULTS A total of 153 participants were randomly assigned to 2 treatment groups (PTED vs MED), and 89.5% (137 patients) completed 1 year of follow-up. Primary and secondary outcomes did not differ significantly between the treatment groups at each prespecified follow-up point (p > 0.05). For PTED, there was less postoperative improvement in ODI score in the median herniation subgroup at 1 week (p = 0.027), 3 months (p = 0.013), 6 months (p = 0.027), and 1 year (p = 0.028) compared with the paramedian subgroup. For MED, there was significantly less improvement in ODI score at 3 months (p = 0.008), 6 months (p = 0.028), and 1 year (p = 0.028) in the far-lateral herniation subgroup compared with the paramedian subgroup. The total complication rate over the course of 1 year was 13.75% in the PTED group and 16.44% in the MED group (p = 0.642). Five patients (6.25%) in the PTED group and 3 patients (4.11%) in the MED group suffered from residue/recurrence of herniation, for which reoperation was required. CONCLUSIONS Over the 1-year follow-up period, PTED did not show superior clinical outcomes and did not seem to be a safer procedure for patients with lumbar disc herniation compared with MED. PTED had inferior results for median disc herniation, whereas MED did not seem to be the best treatment option for far-lateral disc herniation. Clinical trial registration no.: NCT01997086 (clinicaltrials.gov).

Abstract LB-063: Anti-tumor activity of the novel dual p70S6KAKT inhibitor M2698 in glioma stem cell mouse models

The efficacy of the dual p70S6K/AKT inhibitor M2698 was evaluated in a panel of patient-derived glioma stem cell (GSC) lines. The IC50 was determined from a 7-dose cell viability assay using Celltiter Glo. GSCs were classified as sensitive (IC50 ≤ 1µM) or resistant (IC50 &gt;1µM). Two sensitive cell lines (GSC17 and GSC231) and two resistant cell lines (GSC272 and GSC20) were selected for in vivo experiments.

To determine the efficacy of M2698 in orthotopic models of glioblastoma, GSCs were implanted into the basal ganglia of nude mice. After four days, mice were treated with vehicle (control) or M2698 at 20 mg/kg daily M-F. In the cell line GSC231 (sensitive in vitro), the median animal survival time was 47 days in the control-treated mice and 62 days in the M2698-treated mice (p=0.0288). The tumor volumes at 6, 7.5, 10 weeks were 4.98 ± 6.17 mm3, 48.48 ± 10.57 mm3, and 61.38 ± 28.00 mm3, respectively, in the control-treated mice and 0.33 ± 0.45 mm3, 9.96 ± 6.89 mm3, and 18.00 ± 5.59 mm3, respectively, in the M2698 -treated mice (p=0.322, p&lt;0.001, and p=0.05, respectively). To determine the pharmacodynamic effect of the drug in mouse xenografts, the phospho-S6 (P-S6) expression level was evaluated over time (7.5 and 10 weeks). At 7.5 weeks, the P-S6 staining was 11.65 ± 1.17% per field in the control group and 2.61 ± 1.21% per field in the M2698 alone treated group (p&lt;0.004). At 10 weeks , the P-S6 staining was 13.93 ± 3.46% per field in the control group and 3.10 ± 1.23% per field in the M2698 alone treated group (p=0.020).

In the GSC272 (resistant line) xenograft mouse model, the median survival time was 72 days in the control-treated mice and 76 days in the M2698-treated mice. Although this difference was statistically significant (p=0.0022), the 4 day improvement in survival was minimal compared to the sensitive line GSC231. The tumor volumes at 6, 7.5, 10 weeks were 7.48 ± 4.10 mm3, 126.37 ± 41.98 mm3, and 158.79 ± 39.53 mm3, respectively in the control mice and 0.54 ± 0.47 mm3, 8.62 ± 3.88 mm3, and 64.3 ± 5.55 mm3, respectively in the M2698-treated mice (p=0.014, p&lt;0.001, and p=0.008, respectively). The P-S6 expression level at 6 weeks, 7.5 weeks, and 10 weeks was 4.27 ± 3.27% per field, 13.83 ± 4.13% per field, and 22.3 ± 7.67% per field, respectively, in the control-

treated mice and 1.40 ± 1.06% per field, 4.30 ± 2.26% per field, and 5.13 ± 1.02% per field, respectively, in the M2698-treated mice (p=0.302, p=0.005, and p=0.036, respectively).

GSC17 and GSC20 lines that were resistant to M2698 were further evaluated to elucidate potential mechanisms of resistance to p70S6K/AKT inhibitor treatment. Reverse Phase Protein Array (RPPA) assay was performed 24 hours after treatment with M2698 in GSC17 and GSC20 in vitro. M2698 successfully prevented S6 phosphorylation, but also resulted in an increase in P-ERK1/2 and P-MAPK expression suggesting compensatory activation of the Ras/MEK/ERK signaling pathway. To validate these results in vivo, we performed immunohistochemistry staining of P-S6 and P-ERK1/2 in tumor tissue from the GSC17 xenograft model at the latest time points. The data revealed that tumors from M2698-treated mice had lower levels of P-S6 expression and high level of P-ERK1/2 expression compared with the untreated control group. These results suggest that tumors not responsive to p70S6K/AKT inhibitor monotherapy might benefit from combination treatment with a MEK inhibitor.

Citation Format: yuji piao, Craig Thomas, Verlene Henry, Ningyi Tiao, Soon Young park, Martinez-ledesma Juan, Jianwen Dong, John frank de groot. Anti-tumor activity of the novel dual p70S6KAKT inhibitor M2698 in glioma stem cell mouse models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-063. doi:10.1158/1538-7445.AM2017-LB-063

A novel indication for a method in the treatment of lumbar tuberculosis through minimally invasive extreme lateral interbody fusion (XLIF) in combination with percutaneous pedicle screws fixation in an elderly patient: A case report

RATIONALE

To describe a novel indication for a method through minimally invasive extreme lateral interbody fusion (XLIF) in combination with percutaneous pedicle screwsfixation in the treatment of lumbar tuberculosis (TB) in an elderly patient, and its clinical efficacy and feasibility. Lumbar TB is a destructive form of TB. Antituberculous treatment should be started as early as possible. In some circumstances, however, surgical debridement with or without stabilization of the spine appears to be beneficial and may be recommended. Surgeries through the approach of anterior or posterior are still challenging and often involve some complications.

PATIENT CONCERNS

The case is a 68-year-old female who was misdiagnosed as simple vertebral compression fracture and underwent L1 and L2 percutaneous vertebroplasty in another hospital 7 years ago. He complained of lumbosacral pain for 1 month this time. Magnetic resonance imaging (MRI) and computed tomography (CT) showed intervertebral space in L1/2 was seriously damaged like TB.

DIAGNOSES

Lumbar tuberculosis INTERVENTIONS:: Antitubercular drugs, mini-invasive debridement with XLIF in combination with percutaneous pedicle screwsfixation was performed. This patient was followed up for 12 months.

OUTCOMES

No obvious complication occurred during the operation and the wound healed well. Oswestry Disability Index (ODI: 56 vs 22) and visual analog scale (VAS: 4 vs 0) score significantly decreased atfinal follow-up of 12 months. Obvious recovery of kyphosis angle was found postoperatively (post: 14.8° vs pre: 33.5°). No recurrent infection occurred at the last follow-up.

LESSONS

Mini-invasive surgery by debridement through XLIF and percutaneous pedicle screwsfixation may be an effective and innovative treatment method for lumbar TB in the elderly.

Accurate and fast fiber transfer delay measurement based on phase discrimination and frequency measurement

An accurate and fast fiber transfer delay measurement method is demonstrated. As a key technique, a simple ambiguity resolving process based on phase discrimination and frequency measurement is used to overcome the contradiction between measurement accuracy and system complexity. The system achieves a high measurement accuracy of 0.2 ps with a 0.1 ps measurement resolution and a large dynamic range up to 50 km as well as no dead zone.

Abstract 2815: Antitumor activity of CDK4/6 inhibition in combination with radiation therapy on glioblastoma stem cells

Almost 80% of glioblastoma tumors have alterations in the CNKN2A-CDK-Rb pathway. Cyclin dependent kinases 4 and 6 (CDK4/6) act as cell cycle regulators and have been recognized as therapeutic targets for glioblastoma (GBM). In the current study, we determined the antitumor activity of CDK4/6 inhibition (palbociclib and abemaciclib) alone and in combination with radiation on a panel of glioblastoma stem cells (GSCs). The GSCs were molecularly characterized using multiple ‘omimcs’ techniques and Western blots identified specific phospho- and total protein levels. Approximately 50% of cell lines have homozygous deletion of CDKN2A although CDK4 and CDK6 protein expression was significantly elevated in most of the GSCs. RB protein was constitutively phosphorylated in only a subset (45%): GSC11, GSC262, GSC231, GSC304 and GSC7-2. In our panel of GSCs, there were total of three cell lines with CDKN2A loss, RB phosphorylation and CDK4/6 overexpression (GSC262, GSC11 and GSC231). Our data showed that GSC262, GSC11, GSC231 (CDKN2A deletion, RB intact), GSC7-2 and GSC300 (CDKN2A WT, RB intact) were sensitive to CDK4/6 treatment (IC50 ≤ 1μM). CDK4/6 inhibitor treated GSCs showed G1 cell cycle arrest and decreased phospho-RB levels in GSC262 and GSC7-2 cells. We next determined whether CDK4/6 inhibition combined with radiation has additive or synergistic antitumor effect. A clonogenic assay demonstrated that neurosphere formation was significantly decreased by CDK4/6 inhibition in combination with radiation compared to either treatment in GSC262 (resistant to radiation treatment) or GSC7-2 (sensitive to radiation treatment) cell lines. The radiation resistant GSC (GSC262) treated with radiation and CDK4/6 inhibitor became sensitive to radiation therapy whereas radiation sensitive GSC (GSC7-2) had a significant decrease in colony formation compared to radiation alone. CDK4/6 combined with radiation increased γ-H2AX protein expression levels and decreased cyclin D1 protein expression in a time dependent manner compared to single drug treatment. These data indicate synergistic antitumor effects of CDK4/6 inhibition combined with radiation therapy in GSCs in vitro. Further investigation is ongoing to evaluate this combination therapy.

Citation Format: Christopher Nguyen, Yuji Piao, Juan Emmanuel Martinez-Ledesma, Jianwen Dong, Soon Yeung Park, Roel Verhaak, Erik Sulman, John F. De Groot. Antitumor activity of CDK4/6 inhibition in combination with radiation therapy on glioblastoma stem cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2815.

Periostin (POSTN) Regulates Tumor Resistance to Antiangiogenic Therapy in Glioma Models

Periostin (POSTN) interacts with multiple integrins to coordinate a variety of cellular processes, including epithelial-to-mesenchymal transition (EMT) and cell migration. In our previous study, anti-VEGF-A therapy was associated with resistance and EMT. This study sought to determine the role of POSTN in the resistance of glioma stem cells (GSC) to antiangiogenic therapy. In mouse xenograft models of human glioma, POSTN expression was associated with acquired resistance to anti-VEGF-A therapy and had a synergistic effect with bevacizumab in prolonging survival and decreasing tumor volume. Resistance to anti-VEGF-A therapy regulated by POSTN was associated with increased expression of TGFβ1 and hypoxia-inducible factor-1α (HIF1α) in GSCs. At the molecular level, POSTN regulated invasion and expression of EMT (caveolin-1) and angiogenesis-related genes (HIF1α and VEGF-A) through activation of STAT3. Moreover, recombinant POSTN increased GSC invasion. Collectively, our findings suggest that POSTN plays an important role in glioma invasion and resistance to antiangiogenic therapy. Mol Cancer Ther; 15(9); 2187-97. ©2016 AACR.