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.