The semaphorin 3A/neuropilin-1 pathway promotes clonogenic growth of glioblastoma via activation of TGF-β signaling

Glioblastoma (GBM) is the most lethal brain cancer with a dismal prognosis. Stem-like GBM cells (GSCs) are a major driver of GBM propagation and recurrence; thus, understanding the molecular mechanisms that promote GSCs may lead to effective therapeutic approaches. Through in vitro clonogenic growth-based assays, we determined mitogenic activities of the ligand molecules that are implicated in neural development. We have identified that semaphorin 3A (Sema3A), originally known as an axon guidance molecule in the CNS, promotes clonogenic growth of GBM cells but not normal neural progenitor cells (NPCs). Mechanistically, Sema3A binds to its receptor neuropilin-1 (NRP1) and facilitates an interaction between NRP1 and TGF-β receptor 1 (TGF-βR1), which in turn leads to activation of canonical TGF-β signaling in both GSCs and NPCs. TGF-β signaling enhances self-renewal and survival of GBM tumors through induction of key stem cell factors, but it evokes cytostatic responses in NPCs. Blockage of the Sema3A/NRP1 axis via shRNA-mediated knockdown of Sema3A or NRP1 impeded clonogenic growth and TGF-β pathway activity in GSCs and inhibited tumor growth in vivo. Taken together, these findings suggest that the Sema3A/NRP1/TGF-βR1 signaling axis is a critical regulator of GSC propagation and a potential therapeutic target for GBM.

Transgenic viral expression of PH-20, IL-12, and sPD1-Fc enhances immune cell infiltration and anti-tumor efficacy of an oncolytic virus

Oncolytic viruses are of significant clinical interest due to their ability to directly infect and kill tumors and enhance the anti-tumor immune response. Previously, we developed KLS-3010, a novel oncolytic virus derived from the International Health Department-White (IHD-W) strain vaccinia virus, which has robust tumoricidal effects. In the present study, we generated a recombinant oncolytic virus, KLS-3020, by inserting three transgenes (hyaluronidase [PH-20], interleukin-12 [IL-12], and soluble programmed cell death 1 fused to the Fc domain [sPD1-Fc]) into KLS-3010 and investigated its anti-tumor efficacy and ability to induce anti-tumor immune responses in CT26.WT and B16F10 mouse tumor models. A single injection of KLS-3020 significantly decreased tumor growth. The roles of the transgenes were investigated using viruses expressing each single transgene alone and KLS-3020. PH-20 promoted virus spread and tumor immune cell infiltration, IL-12 activated and reprogrammed T cells to inflammatory phenotypes, and sPD1-Fc increased intra-tumoral populations of activated T cells. The tumor-specific systemic immune response and the abscopal tumor control elicited by KLS-3020 were demonstrated in the CT26.WT tumor model. The insertion of transgenes into KLS-3020 increased its anti-tumor efficacy, supporting further clinical investigation of KLS-3020 as a novel oncolytic immunotherapy.

Pharmacogenomic profiling reveals molecular features of chemotherapy resistance in IDH wild-type primary glioblastoma

BACKGROUND

Although temozolomide (TMZ) has been used as a standard adjuvant chemotherapeutic agent for primary glioblastoma (GBM), treating isocitrate dehydrogenase wild-type (IDH-wt) cases remains challenging due to intrinsic and acquired drug resistance. Therefore, elucidation of the molecular mechanisms of TMZ resistance is critical for its precision application.

METHODS

We stratified 69 primary IDH-wt GBM patients into TMZ-resistant (n = 29) and sensitive (n = 40) groups, using TMZ screening of the corresponding patient-derived glioma stem-like cells (GSCs). Genomic and transcriptomic features were then examined to identify TMZ-associated molecular alterations. Subsequently, we developed a machine learning (ML) model to predict TMZ response from combined signatures. Moreover, TMZ response in multisector samples (52 tumor sectors from 18 cases) was evaluated to validate findings and investigate the impact of intra-tumoral heterogeneity on TMZ efficacy.

RESULTS

In vitro TMZ sensitivity of patient-derived GSCs classified patients into groups with different survival outcomes (P = 1.12e-4 for progression-free survival (PFS) and 3.63e-4 for overall survival (OS)). Moreover, we found that elevated gene expression of EGR4, PAPPA, LRRC3, and ANXA3 was associated to intrinsic TMZ resistance. In addition, other features such as 5-aminolevulinic acid negative, mesenchymal/proneural expression subtypes, and hypermutation phenomena were prone to promote TMZ resistance. In contrast, concurrent copy-number-alteration in PTEN, EGFR, and CDKN2A/B was more frequent in TMZ-sensitive samples (Fisher's exact P = 0.0102), subsequently consolidated by multi-sector sequencing analyses. Integrating all features, we trained a ML tool to segregate TMZ-resistant and sensitive groups. Notably, our method segregated IDH-wt GBM patients from The Cancer Genome Atlas (TCGA) into two groups with divergent survival outcomes (P = 4.58e-4 for PFS and 3.66e-4 for OS). Furthermore, we showed a highly heterogeneous TMZ-response pattern within each GBM patient using in vitro TMZ screening and genomic characterization of multisector GSCs. Lastly, the prediction model that evaluates the TMZ efficacy for primary IDH-wt GBMs was developed into a webserver for public usage ( http://www.wang-lab-hkust.com:3838/TMZEP ).

CONCLUSIONS

We identified molecular characteristics associated to TMZ sensitivity, and illustrate the potential clinical value of a ML model trained from pharmacogenomic profiling of patient-derived GSC against IDH-wt GBMs.

Development of postbiotics by whey bioconversion with Enterococcus faecalis M157 KACC81148BP and Lactococcus lactis CAU2013 KACC81152BP for treating periodontal disease and improving gut health

This study developed postbiotics with whey bioconversion product produced by Enterococcus faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and Lactococcus lactis ssp. lactis CAU2013 KACC 81152BP to alleviate periodontitis (PD) and to improve gut health. The powdered whey bioconversion product (EF) produced by E. faecalis M157 KACC 81148BP, mixed whey bioconversion products (EF+LL) from E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP, and phosphate-buffered saline (PBS; control) were administered orally to PD-induced rats for 8 wk. Infiltration of inflammatory cells and epithelial proliferation in periodontal tissue were found in control, but the lesions were reduced in PD+EF group (administration of EF to PD-induced rats), and no lesions were observed in PD+EF+LL group (administration of EF+LL to PD-induced rats). The bone loss volumes in PD+EF and PD+EF+LL groups were lower than in control. Cytokine production levels related to inflammation were lower and antioxidative stress markers were higher in PD+EF and PD+EF+LL groups than in control for both periodontal tissue and gut. The ratios of Lactobacillus spp. in gut microbiome of PD+EF and PD+EF+LL groups were higher than in control. These results indicate that the whey bioconversion product produced by E. faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP are effective on relieving periodontitis and improving the gut health.

Semi-Automated Cell Panning for Efficient Isolation of FGFR3-Targeting Antibody

Phage display technology is a widely used practical tool for isolating binding molecules against the desired targets in phage libraries. In the case of targeting the membrane protein with its natural conformation, conventional bio-panning has limitations on the efficient screening of the functionally relevant antibodies. To enrich the single-chain variable fragment (scFv) pools for recognizing the natural conformation of the membrane targets, the conventional bio-panning and screening process was modified to include the semi-automated cell panning protocol. Using FGFR3-overexpressing patient-derived cancer cells, biotin-X-DHPE was introduced and coupled to Streptavidin-coated magnetic beads for use in the solution-phage bio-panning procedure. The resulting clones of scFv were compared to the diversity of the binding region, especially on CDR-H3. The clones enriched further by cell-based panning procedure possessed a similar binding site and the CDR-H3 loop structure. The resulting antibodies inhibited cell growth and induced target degradation. This process may be a useful tool for screening biologically related antibodies that recognize natural conformational structure on cell membrane protein. Furthermore, cell-based panning has the potential to further expand to a high-throughput screening (HTS) system and automation process.

Fermented milk with Lactobacillus curvatus SMFM2016-NK alleviates periodontal and gut inflammation, and alters oral and gut microbiota

This study aimed to analyze the effect of milk fermented with Lactobacillus curvatus SMFM2016-NK on periodontal diseases and gut health in a rat model. To improve the effect of Lb. curvatus SMFM2016-NK-fermented milk administration for relieving periodontitis, the periodontitis rat models were treated with the following for 4 wk: 10% skim milk (normal), periodontitis + 10% skim milk (negative control), periodontitis + Lactobacillus rhamnosus GG-fermented milk (positive control), and periodontitis + Lb. curvatus SMFM2016-NK-fermented milk (PD+LCFM). Transcriptional analysis of inflammatory cytokines [tumor necrosis factor α (TNF-α), IL-1β, IL-6, and IL-10] was performed via quantitative reverse-transcription PCR. The changes in the oral and gut microbiomes after administering Lb. curvatus SMFM2016-NK-fermented milk were analyzed with metagenomics sequencing using DNA extracted from the oral gingival tissues and feces from the cecum of the rat models. After treatment with Lb. curvatus SMFM2016-NK-fermented milk, the relative gene expression levels of TNFA and IL1B in the gingiva decreased in the PD+LCFM group compared with those in the negative control group. In the oral microbiome, the proportion of the phylum Proteobacteria in the PD+LCFM group was lower than that in the negative control after treatment with Lb. curvatus SMFM2016-NK-fermented milk. For the effect in the gut, the relative gene expression levels of inflammatory cytokines in the colon between the normal and negative control groups were not different; however, the expression levels of TNFA and IL1B in the PD+LCFM and positive control groups, respectively, were lower than those in the negative control group. The composition and diversity of the gut microbiome differed among normal, periodontitis, and Lb. curvatus SMFM2016-NK-fermented milk treatment groups. These results indicate that Lb. curvatus SMFM2016-NK-fermented milk could alleviate periodontal and gut inflammation and change oral and gut microbiota.

Characterization of Gut Microbiome in Korean Patients with Metabolic Associated Fatty Liver Disease

Metabolic associated fatty liver disease (MAFLD) is a new concept where the presence of both fatty liver and metabolic abnormality are necessary for diagnosis. Several studies have reported that altered gut microbiome is closely associated with metabolic diseases and non-alcoholic fatty liver disease. However, the studies on MAFLD population are scarce. This prospective study aimed to identify differences in gut microbiome between patients with MAFLD and healthy controls in Korean population. In this study, patients with MAFLD and age, sex-matched healthy controls were included, and their stool samples were collected. Taxonomic composition of gut microbiota was analyzed using 16S ribosomal ribonucleic acid pyrosequencing. Twenty-two MAFLD patients and 44 healthy controls were included. Taxonomic diversity was lower in patients with MAFLD in the aspect of alpha and beta diversity. The differences were also found at phylum, class, family, and genus levels between the two groups. Phylum Proteobacteria, family Enterobactereriaceae, genus Citrobacter abundance was significantly increased and genus Faecalibacterium was significantly decreased in patients with MAFLD. In addition, butyrate-producing bacteria were decreased and ethanol-producing bacteria were increased in patients with MAFLD. The composition of gut microbiome was different between MAFLD and healthy controls in Korean population. This could offer potential targets for therapeutic intervention in MAFLD.

cIRCR201-dPBD, a Novel Pyrrolobenzodiazepine Dimer-Containing Site-Specific Antibody-Drug Conjugate Targeting c-Met Overexpression Tumors

c-Met, as a receptor expressed on the cell membrane, contributes to the growth and metastasis of tumors, as well as angiogenesis, mainly through the hepatocyte growth factor (HGF)/c-Met axis during tumor progression. Although several c-Met inhibitors, including small molecules and monoclonal antibody inhibitors, are currently being investigated, their clinical outcomes have not been promising. Development of an antibody-drug conjugate (ADC) against c-Met could be an attractive therapeutic strategy that would provide superior antitumor efficacy with broad-spectrum c-Met expression levels. In the present study, site-specific drug-conjugate technology was applied to develop an ADC using the human-mouse cross-reactive c-Met antibody and a prodrug pyrrolobenzodiazepine (PBD). The toxin payload was uniformly conjugated to the light-chain C-terminus of the native cIRCR201 antibody (drug-to-antibody ratio = 2), as confirmed using LC-MS. Using a high-throughput screening system, we found that cIRCR201-dPBD exhibited varying sensitivities depending on the expression levels of c-Met, and it induced receptor-mediated endocytosis and toxin-mediated apoptosis in 47 different cancer cell lines. cIRCR201-dPBD also showed significant antitumor activity on the MET-amplified cancer cells using in vivo xenograft models. Therefore, cIRCR201-dPBD could be a promising therapeutic strategy for tumors with c-Met expression.

Double-filtered leukoreduction as a method for risk reduction of transfusion-associated graft-versus-host disease

Background

Transfusion-associated graft-versus-host disease (TA-GvHD) is caused by leukocytes, specifically T cells within a transfused blood product. Currently, the prevention of transfusion-associated graft-versus-host disease is performed by irradiation of blood products. With a sufficient reduction of leukocytes, the risk for TA-GvHD can be decreased. With consistent advances in current state-of-the-art blood filters, we herein propose that double filtration can sufficiently reduce leukocytes to reduce the risk for TA-GvHD.

Materials

Thirty RBC concentrates were filtered with leukocyte filters, followed by storage at 1–6 ^oC for 72 hours, and then a second filtration was performed. Residual leukocytes in the double-filtered RBC units (n = 30) were assessed with flow cytometric methods, and an additional assay with isolated peripheral blood mononuclear cells (PBMCs) (n = 6) was done by both flow cytometric methods and an automated hematology analyzer. Quality of the RBCs after filtration was evaluated by hematological and biochemical tests. In vitro T cell expansion was performed using anti-CD3/CD28-coated Dynabeads or anti-CD3 (OKT3). In vivo experiment for GvHD was performed by using NOD.Cg-Prkdc^scid Il2rg^tm1Wjl/SzJ (NSG) mice.

Results

Double-filtered blood products showed residual leukocyte levels below detection limits, which calculated to be below 1200–2500 cells per blood unit. In vitro expansion rate of T cells showed that 6x10³ and 1x10³ cell-seeded specimens showed 60.8±10.6 fold and 10.2±9.7-fold expansion, respectively. Cell expansion was not sufficiently observed in wells planted with 1x10² or 10 cells. In vivo experiments showed that mice injected with 1x10⁵ or more cells cause fatal GvHD. GvHD induced inflammation was observed in mice injected with 1x10⁴ or more cells. No evidence of GvHD was found in mice injected with 10³ cells.

Conclusions

Our study suggests that additional removal of contaminating lymphocytes by a second leukodepletion step may further reduce the risk for TA-GvHD.

Abstract P6-17-09: Event-free survival by ADCC status from a follow-up study comparing SB3 (trastuzumab biosimilar) with reference trastuzumab for HER2 positive breast cancer in neoadjuvant setting

Background: SB3 has been approved by the European Commission as a biosimilar of reference trastuzumab (TRZ). Equivalent breast pathologic complete response (bpCR) rate and comparable event-free survival (EFS) and overall survival between SB3 and TRZ have been reported.1-3 Upon monitoring quality attributes of TRZ for the development of SB3, a marked downward shift in antibody-dependent cell-mediated cytotoxicity activities (ADCC) was observed in TRZ lots with expiry dates from Aug 2018 to Dec 2019.4 Some of these lots were used in this study. The objective of this report is to evaluate event-free survival by ADCC status from an additional one-year follow-up study.

Methods: Patients with HER2 positive early or locally advanced breast cancer were randomly assigned to receive SB3 or TRZ in neoadjuvant setting concurrently with chemotherapy. Patients then underwent surgery followed by adjuvant SB3 or TRZ. After completion of therapy, patients from selected countries participated in a long-term follow-up study. In TRZ, patients exposed to at least one shifted ADCC lot and those not exposed to shifted ADCC lot during neoadjuvant period were considered as “Exposed” and “Unexposed,” respectively. EFS was defined as the time from the date of randomization to the date when the first event occurred. An event was defined as disease recurrence or progression (local, regional, distant or contralateral) or death due to any cause. EFS after additional one-year follow-up was analyzed by ADCC status in the long-term follow-up set (LFS).

Results: A total of 367 patients (SB3, N=186; TRZ, N=181) were included in the LFS. Within TRZ, 55 patients were Unexposed and 126 patients were Exposed. At a median follow-up duration of 30.1 months in SB3 and 30.2 months in TRZ from initiation of study treatment, 4.8% patients in SB3, 3.6% in Unexposed and 10.3% in Exposed experienced events. 4.3% patients in SB3, 1.8% in Unexposed and 9.5% in Exposed experienced recurrence after surgery (Table). Two-year EFS rate was 96.7% in SB3, 98.2% in Unexposed and 92.5% in Exposed.

Conclusion: A significantly higher proportion of patients experienced events in Exposed compared to Unexposed (HR 0.07, 95% CI 0.01-0.58, p-value=0.0137). No significant difference in EFS was found between SB3 and Unexposed. Although this study has a relatively short follow-up and has not been powered to evaluate the impact of ADCC on survival, these results suggest a possible correlation between ADCC and clinical efficacy. Further long-term results will follow.

Summary of Event-free Survival (LFS)  TRZEFS Hazard ratio (95% CI), p-value SB3 N=186All N=181Unexposed N=55Exposed N=126SB3 vs TRZ AllSB3 vs TRZ UnexposedTRZ Unexposed vs TRZ ExposedPatients with event, n (%)9 (4.8%)15 (8.3%)2 (3.6%)13 (10.3%)0.49 (0.21, 1.14) p=0.09751.19 (0.23, 6.18) p=0.83760.07 (0.01, 0.58) p=0.0137Recurrence after surgery8 (4.3%)13 (7.2%)1 (1.8%)12 (9.5%)   Progression before surgery1 (0.5%)1 (0.6%)1 (1.8%)0 (0.0%)   Death0 (0.0%)1 (0.6%)0 (0.0%)1 (0.8%)   

Reference:

1. Pivot X et al. J Clin Oncol. 2018; 36:968-74

2. Pivot X et al. Eur J Cancer. 2018; 93:19-27

3. Pivot X et al. J Clin Oncol. 2018; 36 (suppl; abstr e12631)

4. Kim S et al. MAbs. 2017; 9:704-14

Citation Format: Pegram MD, Pivot X, Cortes J, Curigliano G, Yoon Y, Lim J, Song S, Hong E. Event-free survival by ADCC status from a follow-up study comparing SB3 (trastuzumab biosimilar) with reference trastuzumab for HER2 positive breast cancer in neoadjuvant setting [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-09.

A luminous blue kilonova and an off-axis jet from a compact binary merger at z = 0.1341

The recent discovery of a gamma-ray burst (GRB) coincident with the gravitational-wave (GW) event GW170817 revealed the existence of a population of low-luminosity short duration gamma-ray transients produced by neutron star mergers in the nearby Universe. These events could be routinely detected by existing gamma-ray monitors, yet previous observations failed to identify them without the aid of GW triggers. Here we show that GRB150101B is an analogue of GRB170817A located at a cosmological distance. GRB150101B is a faint short burst characterized by a bright optical counterpart and a long-lived X-ray afterglow. These properties are unusual for standard short GRBs and are instead consistent with an explosion viewed off-axis: the optical light is produced by a luminous kilonova, while the observed X-rays trace the GRB afterglow viewed at an angle of ~13°. Our findings suggest that these properties could be common among future electromagnetic counterparts of GW sources.

A faint gamma-ray burst (GRB 170817A) has been recently detected in coincidence with the gravitational wave (GW) event GW 170817. Here, the authors report that another faint short GRB at a cosmological distance (GRB150101B) and its late time emission are analogous to the neutron star merger event GRB 170817A.

Prediction of radiographic abnormalities by the use of bag-of-features and convolutional neural networks

This study evaluated the feasibility of bag-of-features (BOF) and convolutional neural networks (CNN) for computer-aided detection in distinguishing normal from abnormal radiographic findings. Computed thoracic radiographs of dogs were collected. For the purposes of this study, radiographic findings were used to distinguish between normal and abnormal in the following areas: (1) normal cardiac silhouette vs. cardiomegaly, (2) normal lung vs. abnormal lung patterns, (3) normal mediastinal position vs. mediastinal shift, (4) normal pleural space vs. pleural effusion, and (5) normal pleural space vs. pneumothorax. Images for training and testing the models consisted of ventrodorsal and lateral projection images of the same scale. The number of images used for each finding are as follow: 3142 for cardiomegaly (1571 normal and 1571 abnormal from 1143 dogs), 2086 for lung pattern (1043 normal and 1043 abnormal from 1247 dogs), 892 for mediastinal shift (446 normal and 446 abnormal from 387 dogs), 940 for pleural effusion (470 normal and 470 abnormal from 284 dogs), and 78 for pneumothorax (39 normal and 39 abnormal from 61 dogs). All data samples were divided so that 60% would be used for training the algorithms and 40% for testing the two models. The performance of the classifiers was evaluated by calculating the accuracy, sensitivity and specificity. The accuracy of both models ranged from 79.6% to 96.9% in the testing set. CNN showed higher accuracy (CNN; 92.9-96.9% and BOF; 79.6-96.9%) and sensitivity (CNN; 92.1-100% and BOF; 74.1-94.8%) than BOF. In conclusion, both BOF and CNN have potential to be useful for improving work efficiency by double reading.

Pharmacokinetics, Biodistribution, and Toxicity Evaluation of Anti-SEMA3A (F11) in In Vivo Models

BACKGROUND/AIM

The aim of our study was to investigate the pharmacokinetics (PK), tissue distribution and toxicity of F11 antibody to semaphorin 3A in mouse models and explore its anti-angiogenic and tumor-inhibitory effect.

MATERIALS AND METHODS

Patient-derived xenograft (PDX) models were established via subcutaneous implantation of glioblastoma multiforme (GBM) cells and treated with F11.

RESULTS

F11 significantly attenuated tumor growth and angiogenesis in the GBM PDX model. Within the range of administered doses, the PK of F11 in serum demonstrated a linear fashion, consistent with general PK profiles of soluble antigen-targeting antibodies. Additionally, the clearance level was detected at between 4.63 and 7.12 ml/d/kg, while the biological half-life was measured at 6.9 and 9.4 days. Tissue distribution of F11 in kidney, liver and heart was consistent with previously reported antibody patterns. However, the presence of F11 in the brain was an interesting finding.

CONCLUSION

Collectively, our results revealed angiogenic and tumor-inhibitory effect of F11 antibody and its potential therapeutic use within a clinical framework based on PK, biodistribution and toxicity evaluation in mouse models.

Anti-SEMA3A Antibody: A Novel Therapeutic Agent to Suppress Glioblastoma Tumor Growth

Purpose

Glioblastoma (GBM) is classified as one of the most aggressive and lethal brain tumor. Great strides have been made in understanding the genomic and molecular underpinnings of GBM, which translated into development of new therapeutic approaches to combat such deadly disease. However, there are only few therapeutic agents that can effectively inhibit GBM invasion in a clinical framework. In an effort to address such challenges, we have generated anti-SEMA3A monoclonal antibody as a potential therapeutic antibody against GBM progression.

Materials and Methods

We employed public glioma datasets, Repository of Molecular Brain Neoplasia Data and The Cancer Genome Atlas, to analyze SEMA3AmRNA expression in human GBM specimens. We also evaluated for protein expression level of SEMA3A via tissue microarray (TMA) analysis. Cell migration and proliferation kinetics were assessed in various GBM patient-derived cells (PDCs) and U87-MG cell-line for SEMA3A antibody efficacy. GBM patient-derived xenograft (PDX) models were generated to evaluate tumor inhibitory effect of anti-SEMA3A antibody in vivo.

Results

By combining bioinformatics and TMA analysis, we discovered that SEMA3A is highly expressed in human GBM specimens compared to non-neoplastic tissues. We developed three different anti-SEMA3A antibodies, in fully human IgG form, through screening phage-displayed synthetic antibody library using a classical panning method. Neutralization of SEMA3A significantly reduced migration and proliferation capabilities of PDCs and U87-MG cell line in vitro. In PDX models, treatment with anti-SEMA3A antibody exhibited notable tumor inhibitory effect through down-regulation of cellular proliferative kinetics and tumor-associated macrophages recruitment.

Conclusion

In present study, we demonstrated tumor inhibitory effect of SEMA3A antibody in GBM progression and present its potential relevance as a therapeutic agent in a clinical framework.

In vivo RNAi screen identifies NLK as a negative regulator of mesenchymal activity in glioblastoma

Glioblastoma (GBM) is the most lethal brain cancer with profound genomic alterations. While the bona fide tumor suppressor genes such as PTEN, NF1, and TP53 have high frequency of inactivating mutations, there may be the genes with GBM-suppressive roles for which genomic mutation is not a primary cause for inactivation. To identify such genes, we employed in vivo RNAi screening approach using the patient-derived GBM xenograft models. We found that Nemo-Like Kinase (NLK) negatively regulates mesenchymal activities, a characteristic of aggressive GBM, in part via inhibition of WNT/β-catenin signaling. Consistent with this, we found that NLK expression is especially low in a subset of GBMs that harbors high WNT/mesenchymal activities. Restoration of NLK inhibited WNT and mesenchymal activities, decreased clonogenic growth and survival, and impeded tumor growth in vivo. These data unravel a tumor suppressive role of NLK and support the feasibility of combining oncogenomics with in vivo RNAi screen.

Evaluation of Salmonella Growth at Low Concentrations of NaNO2 and NaCl in Processed Meat Products Using Probabilistic Model

This study developed probabilistic models to predict Salmonella growth in processed meat products formulated with varying concentrations of NaCl and NaNO2. A five-strain mixture of Salmonella was inoculated in nutrient broth supplemented with NaCl (0%, 0.25%, 0.5%, 0.75%, 0.5%, 1.0%, 1.25%, and 1.75%) and NaNO2 (0, 15, 30, 45, 60, 75, 90, 105, and 120 ppm). The inoculated samples were then incubated under aerobic and anaerobic conditions at 4°C, 7°C, 10°C, 12°C, and 15°C for up to 60 days. Growth (assigned the value of 1) or no growth (assigned the value of 0) for each combination was evaluated by turbidity. These growth response data were analyzed with a logistic regression to evaluate the effect of NaCl and NaNO2 on Salmonella growth. The results from the developed model were compared to the observed data obtained from the frankfurters to evaluate the performance of the model. Results from the developed model showed that a single application of NaNO2 at low concentrations did not inhibit Salmonella growth, whereas NaCl significantly (p<0.05) inhibited Salmonella growth at 10°C, 12°C, and 15°C, regardless of the presence of oxygen. At 4°C and 7°C, Salmonella growth was not observed in either aerobic or anaerobic conditions. When NaNO2 was combined with NaCl, the probability of Salmonella growth decreased. The validation value confirmed that the performance of the developed model was appropriate. This study indicates that the developed probabilistic models should be useful for describing the combinational effect of NaNO2 and NaCl on inhibiting Salmonella growth in processed meat products.

Quantitative analysis of a spinal surgeon’s learning curve for scoliosis surgery

Aims

The aim of this study was a quantitative analysis of a surgeon’s learning curve for scoliosis surgery and the relationship between the surgeon’s experience and post-operative outcomes, which has not been previously well described.

Patients and Methods

We have investigated the operating time as a function of the number of patients to determine a specific pattern; we analysed factors affecting the operating time and compared intra- and post-operative outcomes. We analysed 47 consecutive patients undergoing scoliosis surgery performed by a single, non-trained scoliosis surgeon. Operating time was recorded for each of the four parts of the procedures: dissection, placement of pedicle screws, reduction of the deformity and wound closure.

Results

The median operating time was 310 minutes (interquartile range 277.5 to 432.5). The pattern showed a continuous decreasing trend in operating time until the patient number reached 23 to 25, after which it stabilised with fewer patient-dependent changes. The operating time was more affected by the patient number (r =- 0.75) than the number of levels fused (r = 0.59). Blood loss (p = 0.016) and length of stay in hospital (p = 0.012) were significantly less after the operating time stabilised. Post-operative functional outcome scores and the rate of complications showed no significant differences. Take home message: We describe a detailed learning curve for scoliosis surgery based on a single surgeon’s practise, providing useful information for novice scoliosis surgeons and for those responsible for training in spinal surgery. Cite this article: Bone Joint J 2016;98-B:679–85.

Investigations on flame dynamics of premixed H2–air mixtures in microscale tubes

The flame propagation is affected by flame shape angle and wall heat transfer coeff. A minimum flame propagation speed is observed for planar flames with nearly zero flame shape angle for 580 h⁻² K⁻¹ wall heat transfer coeff. range.

Natural killer (NK) cells inhibit systemic metastasis of glioblastoma cells and have therapeutic effects against glioblastomas in the brain

BACKGROUND

Glioblastoma multiforme (GBM) is characterized by extensive local invasion, which is in contrast with extremely rare systemic metastasis of GBM. Molecular mechanisms inhibiting systemic metastasis of GBM would be a novel therapeutic candidate for GBM in the brain.

METHODS

Patient-derived GBM cells were primarily cultured from surgical samples of GBM patients and were inoculated into the brains of immune deficient BALB/c-nude or NOD-SCID IL2Rgamma(null) (NSG) mice. Human NK cells were isolated from peripheral blood mononucleated cells and expanded in vitro.

RESULTS

Patient-derived GBM cells in the brains of NSG mice unexpectedly induced spontaneous lung metastasis although no metastasis was detected in BALB/c-nude mice. Based on the difference of the innate immunity between two mouse strains, NK cell activities of orthotopic GBM xenograft models based on BALB/c-nude mice were inhibited. NK cell inactivation induced spontaneous lung metastasis of GBM cells, which indicated that NK cells inhibit the systemic metastasis. In vitro cytotoxic activities of human NK cells against GBM cells indicated that cytotoxic activity of NK cells against GBM cells prevents systemic metastasis of GBM and that NK cells could be effective cell therapeutics against GBM. Accordingly, NK cells transplanted into orthotopic GBM xenograft models intravenously or intratumorally induced apoptosis of GBM cells in the brain and showed significant therapeutic effects.

CONCLUSIONS

Our results suggest that innate NK immunity is responsible for rare systemic metastasis of GBM and that sufficient supplementation of NK cells could be a promising immunotherapeutic strategy for GBM in the brain.

GC1118, an Anti-EGFR Antibody with a Distinct Binding Epitope and Superior Inhibitory Activity against High-Affinity EGFR Ligands

The EGFR-targeted monoclonal antibodies are a valid therapeutic strategy for patients with metastatic colorectal cancer (mCRC). However, only a small subset of mCRC patients has therapeutic benefits and there are high demands for EGFR therapeutics with a broader patient pool and more potent efficacy. In this study, we report GC1118 exhibiting a different character in terms of binding epitope, affinity, mode of action, and efficacy from other anti-EGFR antibodies. Structural analysis of the EGFR-GC1118 crystal complex revealed that GC1118 recognizes linear, discrete N-terminal epitopes of domain III of EGFR, critical for EGF binding but not overlapping with those of other EGFR-targeted antibodies. GC1118 exhibited superior inhibitory activity against high-affinity EGFR ligands in terms of EGFR binding, triggering EGFR signaling, and proliferation compared with cetuximab and panitumumab. EGFR signaling driven by low-affinity ligands, on the contrary, was well inhibited by all the antibodies tested. GC1118 demonstrated robust antitumor activity in tumor xenografts with elevated expression of high-affinity ligands in vivo, whereas cetuximab did not. Considering the significant role of high-affinity EGFR ligands in modulating tumor microenvironment and inducing resistance to various cancer therapeutics, our study suggests a potential therapeutic advantage of GC1118 in terms of efficacy and a range of benefited patient pool. Mol Cancer Ther; 15(2); 251-63. ©2015 AACR.

Spatiotemporal Evolution of the Primary Glioblastoma Genome

Tumor recurrence following treatment is the major cause of mortality for glioblastoma multiforme (GBM) patients. Thus, insights on the evolutionary process at recurrence are critical for improved patient care. Here, we describe our genomic analyses of the initial and recurrent tumor specimens from each of 38 GBM patients. A substantial divergence in the landscape of driver alterations was associated with distant appearance of a recurrent tumor from the initial tumor, suggesting that the genomic profile of the initial tumor can mislead targeted therapies for the distally recurred tumor. In addition, in contrast to IDH1-mutated gliomas, IDH1-wild-type primary GBMs rarely developed hypermutation following temozolomide (TMZ) treatment, indicating low risk for TMZ-induced hypermutation for these tumors under the standard regimen.

USP1 targeting impedes GBM growth by inhibiting stem cell maintenance and radioresistance

BACKGROUND

Clinical benefits from standard therapies against glioblastoma (GBM) are limited in part due to intrinsic radio- and chemoresistance of GBM and inefficient targeting of GBM stem-like cells (GSCs). Novel therapeutic approaches that overcome treatment resistance and diminish stem-like properties of GBM are needed.

METHODS

We determined the expression levels of ubiquitination-specific proteases (USPs) by transcriptome analysis and found that USP1 is highly expressed in GBM. Using the patient GBM-derived primary tumor cells, we inhibited USP1 by shRNA-mediated knockdown or its specific inhibitor pimozide and evaluated the effects on stem cell marker expression, proliferation, and clonogenic growth of tumor cells.

RESULTS

USP1 was highly expressed in gliomas relative to normal brain tissues and more preferentially in GSC enrichment marker (CD133 or CD15) positive cells. USP1 positively regulated the protein stability of the ID1 and CHEK1, critical regulators of DNA damage response and stem cell maintenance. Targeting USP1 by RNA interference or treatment with a chemical USP1 inhibitor attenuated clonogenic growth and survival of GSCs and enhanced radiosensitivity of GBM cells. Finally, USP1 inhibition alone or in combination with radiation significantly prolonged the survival of tumor-bearing mice.

CONCLUSION

USP1-mediated protein stabilization promotes GSC maintenance and treatment resistance, thereby providing a rationale for USP1 inhibition as a potential therapeutic approach against GBM.

Targeting the epithelial to mesenchymal transition in glioblastoma: the emerging role of MET signaling

Glioblastoma multiforme (GBM) is the most common human primary brain malignancy and has a dismal prognosis. Aggressive treatments using maximal surgical resection, radiotherapy, and temozolomide result in median survival of only 14.6 months in patients with GBM. Numerous clinical approaches using small molecule inhibitors have shown disappointing results because of the genetic heterogeneity of GBM. The epithelial to mesenchymal transition (EMT) is a crucial biological process occurring in the early development stages of many species. However, cancer cells often obtain the ability to invade and metastasize through the EMT, which triggers the scattering of cells. The hepatocyte growth factor (HGF)/MET signaling pathway is indicative of the EMT during both embryogenesis and the invasive growth of tumors, because HGF potently induces mesenchymal transition in epithelial-driven cells. Activation of MET signaling or co-overexpression of HGF and MET frequently represents aggressive growth and poor prognosis of various cancers, including GBM. Thus, efforts to treat cancers by inhibiting MET signaling using neutralizing antibodies or small molecule inhibitors have progressed during the last decade. In this review, we discuss HGF/MET signaling in the development of diseases, including cancers, as well as updates on MET inhibition therapy.

Translational validation of personalized treatment strategy based on genetic characteristics of glioblastoma

Glioblastoma (GBM) heterogeneity in the genomic and phenotypic properties has potentiated personalized approach against specific therapeutic targets of each GBM patient. The Cancer Genome Atlas (TCGA) Research Network has been established the comprehensive genomic abnormalities of GBM, which sub-classified GBMs into 4 different molecular subtypes. The molecular subtypes could be utilized to develop personalized treatment strategy for each subtype. We applied a classifying method, NTP (Nearest Template Prediction) method to determine molecular subtype of each GBM patient and corresponding orthotopic xenograft animal model. The models were derived from GBM cells dissociated from patient's surgical sample. Specific drug candidates for each subtype were selected using an integrated pharmacological network database (PharmDB), which link drugs with subtype specific genes. Treatment effects of the drug candidates were determined by in vitro limiting dilution assay using patient-derived GBM cells primarily cultured from orthotopic xenograft tumors. The consistent identification of molecular subtype by the NTP method was validated using TCGA database. When subtypes were determined by the NTP method, orthotopic xenograft animal models faithfully maintained the molecular subtypes of parental tumors. Subtype specific drugs not only showed significant inhibition effects on the in vitro clonogenicity of patient-derived GBM cells but also synergistically reversed temozolomide resistance of MGMT-unmethylated patient-derived GBM cells. However, inhibitory effects on the clonogenicity were not totally subtype-specific. Personalized treatment approach based on genetic characteristics of each GBM could make better treatment outcomes of GBMs, although more sophisticated classifying techniques and subtype specific drugs need to be further elucidated.

Kinetic Behavior of Escherichia coli on Various Cheeses under Constant and Dynamic Temperature

In this study, we developed kinetic models to predict the growth of pathogenic Escherichia coli on cheeses during storage at constant and changing temperatures. A five-strain mixture of pathogenic E. coli was inoculated onto natural cheeses (Brie and Camembert) and processed cheeses (sliced Mozzarella and sliced Cheddar) at 3 to 4 log CFU/g. The inoculated cheeses were stored at 4, 10, 15, 25, and 30°C for 1 to 320 h, with a different storage time being used for each temperature. Total bacteria and E. coli cells were enumerated on tryptic soy agar and MacConkey sorbitol agar, respectively. E. coli growth data were fitted to the Baranyi model to calculate the maximum specific growth rate (μ max; log CFU/g/h), lag phase duration (LPD; h), lower asymptote (log CFU/g), and upper asymptote (log CFU/g). The kinetic parameters were then analyzed as a function of storage temperature, using the square root model, polynomial equation, and linear equation. A dynamic model was also developed for varying temperature. The model performance was evaluated against observed data, and the root mean square error (RMSE) was calculated. At 4°C, E. coli cell growth was not observed on any cheese. However, E. coli growth was observed at 10°C to 30°C with a μ max of 0.01 to 1.03 log CFU/g/h, depending on the cheese. The μ max values increased as temperature increased, while LPD values decreased, and μ max and LPD values were different among the four types of cheese. The developed models showed adequate performance (RMSE = 0.176-0.337), indicating that these models should be useful for describing the growth kinetics of E. coli on various cheeses.

Antiangiogenic Therapy with Human Apolipoprotein(a) Kringle V and Paclitaxel in a Human Ovarian Cancer Mouse Model

INTRODUCTION: The present study compared the effect of combination therapy using human apolipoprotein(a) kringle V (rhLK8) to conventional chemotherapy with paclitaxel for human ovarian carcinoma producing high or low levels of vascular endothelial growth factor (VEGF). MATERIALS AND METHODS: Human ovarian carcinoma cells producing high (SKOV3ip1) or low (HeyA8) levels of VEGF were implanted into the peritoneal cavity of female nude mice. Seven days later, mice were randomized into four groups: control (vehicle), paclitaxel [5 mg/kg, weekly intraperitoneal (i.p.) injection], rhLK8 (50 mg/kg, daily i.p. injection), or the combination of paclitaxel and rhLK8. Mice were treated for 4 weeks and examined by necropsy. RESULTS: In mice implanted with SKOV3ip1 cells, rhLK8 treatment had no significant effect on tumor incidence or the volume of ascites but induced a significant decrease in tumor weight compared with control mice. Paclitaxel significantly reduced tumor weight and ascites volume, and combination treatment with paclitaxel and rhLK8 had an additive therapeutic effect. Similarly, in HeyA8 mice, the effect of combination treatment on tumor weight and tumor incidence was statistically significantly greater than that of paclitaxel or rhLK8 alone. Immunohistochemical analysis showed a significant decrease in microvessel density and a marked increase of apoptosis in tumor and tumor-associated endothelial cells in response to combination treatment with paclitaxel and rhLK8. CONCLUSION: Collectively, these results suggest that antiangiogenic therapy with rhLK8 in combination with taxane-based conventional chemotherapy could be effective for the treatment of ovarian carcinomas, regardless of VEGF status.

Vaccinia-based influenza vaccine overcomes previously induced immunodominance hierarchy for heterosubtypic protection

Growing concerns about unpredictable influenza pandemics require a broadly protective vaccine against diverse influenza strains. One of the promising approaches was a T cell-based vaccine, but the narrow breadth of T-cell immunity due to the immunodominance hierarchy established by previous influenza infection and efficacy against only mild challenge condition are important hurdles to overcome. To model T-cell immunodominance hierarchy in humans in an experimental setting, influenza-primed C57BL/6 mice were chosen and boosted with a mixture of vaccinia recombinants, individually expressing consensus sequences from avian, swine, and human isolates of influenza internal proteins. As determined by IFN-γ ELISPOT and polyfunctional cytokine secretion, the vaccinia recombinants of influenza expanded the breadth of T-cell responses to include subdominant and even minor epitopes. Vaccine groups were successfully protected against 100 LD50 challenges with PR/8/34 and highly pathogenic avian influenza H5N1, which contained the identical dominant NP366 epitope. Interestingly, in challenge with pandemic A/Cal/04/2009 containing mutations in the dominant epitope, only the group vaccinated with rVV-NP + PA showed improved protection. Taken together, a vaccinia-based influenza vaccine expressing conserved internal proteins improved the breadth of influenza-specific T-cell immunity and provided heterosubtypic protection against immunologically close as well as distant influenza strains.

Tuning the Fano resonance with an intruder continuum

Through a combination of experiment and theory we establish the possibility of achieving strong tuning of Fano resonances (FRs), by allowing their usual two-path geometry to interfere with an additional, "intruder", continuum. As the coupling strength to this intruder is varied, we predict strong modulations of the resonance line shape that, in principle at least, may exceed the amplitude of the original FR itself. For a proof-of-concept demonstration of this phenomenon, we construct a nanoscale interferometer from nonlocally coupled quantum point contacts and utilize the unique features of their density of states to realize the intruder. External control of the intruder coupling is enabled by means of an applied magnetic field, in the presence of which we demonstrate the predicted distortions of the FR. This general scheme for resonant control should be broadly applicable to a variety of wave-based systems, opening up the possibility of new applications in areas such as chemical and biological sensing and secure communications.

Characterization of CD45-/CD31+/CD105+ circulating cells in the peripheral blood of patients with gynecologic malignancies

PURPOSE

Circulating endothelial cells (CEC) have been widely used as a prognostic biomarker and regarded as a promising strategy for monitoring the response to treatment in several cancers. However, the presence and biologic roles of CECs have remained controversial for decades because technical standards for the identification and quantification of CECs have not been established. Here, we hypothesized that CECs detected by flow cytometry might be monocytes rather than endothelial cells.

EXPERIMENTAL DESIGN

The frequency of representative CEC subsets (i.e., CD45(-)/CD31(+), CD45(-)/CD31(+)/CD146(+), CD45(-)/CD31(+)/CD105(+)) was analyzed in the peripheral blood of patients with gynecologic cancer (n = 56) and healthy volunteers (n = 44). CD45(-)/CD31(+) cells, which are components of CECs, were isolated and the expression of various markers (CD146, CD105, vWF, and CD144 for endothelial cells; CD68 and CD14 for monocytes) was examined by immunocytochemistry.

RESULTS

CD45(-)/CD31(+)/CD105(+) cells were significantly increased in the peripheral blood of patients with cancer, whereas evaluation of CD45(-)/CD31(+)/CD146(+) cells was not possible both in patients with cancer and healthy controls due to the limited resolution of the flow cytometry. Immunocytochemistry analyses showed that these CD45(-)/CD31(+)/CD105(+) cells did not express vWF and CD146 but rather CD144. Furthermore, CD45(-)/CD31(+)/CD105(+) cells uniformly expressed the monocyte-specific markers CD14 and CD68. These results suggest that CD45(-)/CD31(+)/CD105(+) cells carry the characteristics of monocytes rather than endothelial cells.

CONCLUSIONS

Our data indicate that CD45(-)/CD31(+)/CD105(+) circulating cells, which are significantly increased in the peripheral blood of patients with gynecologic cancer, are monocytes rather than endothelial cells. Further investigation is required to determine the biologic significance of their presence and function in relation with angiogenesis.