bluuebunny/crossref_metadata_2025_split huggingface dataset:
P09.08 Increased incidence of intracranial meningiomas in patients with acromegaly
Authors: Engelhardt J , Nunes M , Pouchieu C , San-Galli F , Gimbert E , Vignes J , Laurent F , Berge J , Baldi I , Tabarin A , Loiseau H 
Published: September 2019

Abstract

BACKGROUND
An increased incidence of various neoplasms has been described in patients with acromegaly and there is evidence to suggest that growth factors are risk factors for the development of meningiomas. We aimed to study if patients with acromegaly are more at risk for developing intracranial meningiomas

MATERIAL AND METHODS
We conducted an observational study on 221 consecutive acromegalic patients recruited between January 1, 2000 and December 31, 2015, and 357 consecutive patients with a non-somatotropic pituitary adenoma recruited between March 1, 2015 and December 31, 2016 in our institution. Patients underwent a gadolinium-enhanced 3D T1 brain MRI to look for meningiomas. The proportion of meningiomas was compared between the two groups and the standardized incidence ratio (SIR) was computed from the incidence rates of meningiomas observed in the population of acromegalic patients and compared to that of the general population given by the local registry of central nervous system tumors.

RESULTS
Patients with acromegaly had a significant risk for developing intracranial meningiomas as compared to patients without acromegaly (7.7% vs. 2.2%, p = .005, OR = 3.45 [1.46; 8.15]). There was a significant increased incidence of intracranial meningiomas in patients with acromegaly (SIR = 126 [25; 367]) as compared to the general population.

CONCLUSION
Our study provides the first evidence that patients with acromegaly are more at risk for developing intracranial meningiomas.
P10.03 Immunological differences between patient-matched normal-derived and GBM-derived pericytes
Authors: Macapagal J , Brooks A , Schweder P , Mee E , Faull R , Park T I H , Dragunow M 
Published: September 2019

Abstract

BACKGROUND
Glioblastoma Multiforme (GBM) is the most aggressive, fatal, yet most common form of brain malignancy in adults. Despite advances in immune-based treatments for other modes of cancer, GBM remains a challenge due to its ability to dampen immune responses via mechanisms not yet fully understood. With a median survival time of only 15 months following diagnosis, there is a strong push to find new targets for therapy. The microenvironment comprises a mixture of malignant tumour cells, stroma, blood vessels and infiltrating inflammatory cells. Despite advances in understanding the contribution of these cells in establishing an anti-inflammatory microenvironment, the contribution of pericytes, an important neurovascular mural cell that forms the blood-brain barrier, has been inadequately studied. Therefore, we investigated the differences in immune profile between patient-matched non-neoplastic brain- and GBM-derived pericytes under basal and induced conditions.

MATERIAL AND METHODS
Primary patient-matched non-neoplastic brain and GBM tumour derived pericytes were isolated from specimens excised from consenting patients undergoing GBM surgical resection at Auckland City Hospital. Pericytes were treated with inflammatory cytokines including IL-1β, IFN-γ, TNFα and TGFβ for up to 24 hours. Inflammatory profile changes were probed for using fluorescent immunocytochemistry, qRT-PCR and spectral flow cytometry. Media was also collected for secretome analysis via cytometric bead array.

RESULTS
GBM pericytes show decreased expression of CX3CL1, both basally and following IL-1β treatment, via qRT-PCR and CBA. In contrast, increased gene expression and secretion of IL-6 and IL-8 by GBM pericytes were observed. GBM pericytes also basally express CD90 and anti-inflammatory molecule PD-L1 compared to their normal counterparts. In terms of activated pathways, basal SMAD2/3 activation is increased in GBM pericytes, while also showing greater activation following treatment with IL-1β, IFN-γ but not TNFα. C/EBPδ is activated and translocated following inflammatory stimulation; however, shows localised expression within the cytoplasm only observed in GBM pericytes.

CONCLUSION
This immunological screen of GBM pericytes highlights them as key players in the establishment of the tumour microenvironment. With data suggesting the activation of pathways such as the SMAD2/3 pathway in an unconventional manner, it suggests the potential for pericytes to manipulate pathways towards a more immunosuppressive outcome. Further immune characterisation of such cells is required to fully understand how they might contribute to the immunosuppressive nature of GBM.
P10.05 NKG2DL expression and dormancy in cerebral metastases: impact of chemotherapeutic treatment
Authors: Flueh C , Hufnagel R , Synowitz M , Held-Feindt J 
Published: September 2019

Abstract
Background: Cerebral metastases are common intracranial lesions and have enormous prognostic impact. In many cases, brain metastases seem to be insensitive to chemotherapeutic treatment and are often source of recurrence. To date, the reasons for this are not entirely known. Dormant tumor cells are a population of non-apoptotic, low proliferating cells, which have the ability to be reactivated and can be the source of recurrence. Another mechanism of tumor cell survival are immunological escape mechanisms, involving the Natural Killer Group 2, member D (nkg2d) receptor-ligand system. In a previous study we were able to show that human brain metastases of pulmonary and breast cancer harbor a significant amount of dormant tumor cells, which often coexpress NKG2D ligands. We now wanted to investigate, whether chemotherapeutic treatment has an effect on expression of dormancy markers and nkg2d ligands.
Materials and Methods: The murine breast cancer cell line E0771 and the murine pulmonary cancer cell line LLC were treated with ascending doses of cisplatin and cyclophosphamid, two chemotherapeutics which are also used in humans, for 2 to 10 days in comparison to negative controls. We performed a cytotoxicity assay. Expression of the dormancy-associated markers pdgf, fgf2, hif1alpha, epha5, h2bk and igfbp5 and the nkg2d ligands mult1, h60a, h60b, h60c and raet1b were analyzed by qrtPCR and immunocytochemistry (IHC).
Results: Cytotoxicity assay revealed, that cells from both lines died significantly after treatment with Cisplatin in comparison to control conditions. Whereas cyclophosphamide had no effect on dormancy marker and nkg2dl expression, treatment with cisplatin led to a significant upregulation of many nkg2dl and dormancy marker expression in LLC and E0771 in a dose and time dependent manner. Results were confirmed via IHC.Conclusions: Although chemotherapy with cisplatin leads to death of many cells in culture, the surviving cells show a high expression of dormancy markers and of certain nkg2d ligands. Not only acquisition of dormancy but also nkg2d ligand expression might play an important role in chemoresistance of brain metastases. Markers from both groups could therefore be effective therapeutic targets.
P11.13 Radiotherapy combined with a multimodal imaging approach in a glioblastoma preclinical model
Authors: Salvatore D , Shaw G , Wright J , Teh I , Koch-Paszkowski J , Murray L , Scarsbrook A , Schneider J , Ottobrini L , Short S 
Published: September 2019

Abstract

BACKGROUND
Glioblastoma multiforme (GBM) carries a poor prognosis, partly due to biological and anatomical heterogeneity. Although radiotherapy (RT) is effective, high doses damage surrounding healthy tissues. Multimodal imaging with Magnetic Resonance (MRI) and Positron Emission Tomography (PET) may represent a useful approach for identifying GBM heterogeneity and visualising metabolic tumour properties. PET radiotracer [18F]-fluciclovine is preferentially accumulated in gliomas compared to healthy brain tissue via the cellular transport systems, LAT1 and ASCT2. In this study the effect of fractionated RT using multimodal imaging including [18F]-fluciclovine uptake and immunohistochemistry (IHC) in a GBM preclinical model will be validated.

MATERIAL AND METHODS
Two C57BL/6J mice cohorts were injected intracranially (i.c.) with murine CT2A-luc cells and subsequently submitted to multiparametric MRI and [18F]-fluciclovine PET imaging during hemi-brain RT (3Gy on 2 days/each week) for maximum 25 days after i.c. injection. Brains were collected for IHC characterization including LAT1 and ASCT2 staining.

RESULTS
Preliminary data showed that both MRI and PET were effective modalities to track tumour growth in this model. PET data revealed up to greater than 3-fold increase in SUVmax from regions of interest around the tumour site compared to healthy brain tissue. Time activity curves showed a steady increase in tumour uptake over 90 minutes. MRI showed a 25% increase in T2 values in tumours relative to unaffected contralateral regions. Confirmation of treatment response through matched imaging and IHC are ongoing, from which changes in glioma cell biology as well as amino acid transporter protein levels will be analysed.

CONCLUSION
These preliminary results show that multimodal imaging presents novel data in the assessment of treatment response in this model and will permit parallel IHC analyses to better define GBM tumour heterogeneity aligned with imaging changes. These data will also inform an on-going clinical study using the same imaging modalities.
Work at authors’ labs are supported by an Investigator initiated project from Blue Earth Diagnostics (AS, SCS) and a University of Leeds Biswas studentship (SCS, DS). Daniela Salvatore is also supported by a Scholarship provided by Molecular and Translational Medicine Doctorate School of University of Milan (Italy).
P11.30 Special VEGF90kDa form in exosome from GBM cells activates TAZ in endothelial cells to promote angiogenesis and contributes bevacizumab resistance
Authors: Wang Z , Yuan Y , Xu C , Liu Y 
Published: September 2019

Abstract

BACKGROUND
Glioblastoma (GBM) has obvious blood vessels proliferation, which is one of the important histological diagnostic criteria. Bevacizumab, VEGF targeted inhibitor, is found inefficient in 2/3 cases after the clinical trial. Here, we found a specific 90kDa form of VEGF (VEGF90K) in exosomes of GBM could activate TAZ expression in endothelial cells to promote angiogenesis, which might also contribute to Bevacizumab treatment resistance.

MATERIAL AND METHODS
Exosomes were isolated from U87, LN229 GBM cell culture medium and characterized using transmission electron microscopy, nanoparticle analysis, and western blotting. VEGF expression in GBM and TAZ expression in human umbilical vein endothelial cells (HUVEC) are inhibited by shRNA. In vitro migration, proliferation, and tube formation assays were used to assess the angiogenic potential of HUVEC cells. Western blotting was used to analysis TAZ expression in HUVEC. Bevacizumab or exosome inhibitor GW4869 were used separately or together to evaluation their blocking effects on angiogenic functions of GBM cells.

RESULTS
we found a unique 90kDa form of VEGF (VEGF90K) from exosome of GBM cells could activate TAZ expression in HUVEC cells which correlated with higher levels of cellular migration, proliferation, and tube formation. Knockdown VEGF expression in GBM exosomes or TAZ expression in HUVEC cells could decrease the angiogenic function of GBM cells. GW4869 combine Bevacizumab had significantly inhibited the angiogenic ability of GBM cells in vivo and in vitro.

CONCLUSION
A specific exosome-associated VEGF from GBM can promote angiogenesis by activating TAZ expression in endothelial cells. Targeted inhibition of exosome secretion can significantly inhibit tumor angiogenesis and restore bevacizumab effect. Our study highlights the unique properties of VEGF in exosome which might help to explore new treatment strategies of GBM.
P11.38 The Galectin-1 inhibitor OTX-008 has antiproliferative effects on human glioblastoma cells independent of MGMT-promotor status
Authors: Goett H , Kolodziej M , Pons-Kühnemann J , Schwarm F , Koch C , Uhl E , Stein M 
Published: September 2019

Abstract

BACKGROUND
The protein Galectin-1 (gal-1) is known to be involved in proliferation and progression of several malignancies. The allosteric gal-1 inhibitor OTX-008 has an antiproliferative effect on various tumors in vitro and in vivo. However, the effect of OTX-008 on patient derived GBM cultures is unknown. The aim of our study was to investigate the antiproliferative effects of OTX-008 on U87-MG and A172 cells, patient derived GBM cultures, and cultured human astrocytes (HCA).

MATERIAL AND METHODS
GBM specimens from 10 patients were intraoperatively retrieved out of the 5-ALA-positive areas and were cultured in DMEM. In these cell cultures, U87-MG and A172 cell lines, and in HCA the gal-1 expression was determined by quantitative RT-PCR. Gal-1 expression below the median was defined as low-gal-1 expression (LGE), above as high-gal-1 expression (HGE). OTX-008 was administered and cell viability was assessed after 72h with MTT assay. Dose-response curves and influence of gal-1 expression were calculated by probit analysis in a logit model with logarithmic transformation of x-axis. Comparison between MGMT promotor methylated and unmethylated cells was performed using the Mann-Whitney U test.

RESULTS
OTX-008 inhibited cell proliferation of all 10 patient derived GBM cell cultures with a mean ED50 of 34.28 (95% CI: 20.29- 61.57) μM and a mean ED95 of 100.90 (59.30- 199.33) μM. Antiproliferative effects of OTX-008 for U87-MG and A172 cells were found with an ED50 of 17.44 (95% CI: 13.24- 22.52) μM and 33.36 (95% CI: 24.30- 45.86) μM. In 5 cell cultures of the patient derived cells LGE and in the other 5 HGE was determined. Probit analysis showed an ED50 of 20.43 (95% CI: 16.03- 24.89) μM for the LGE group and an ED50 of 33.98 (95% CI: 28.15- 40.89) μM for the HGE-group. Between MGMT-promotor methylated and unmethylated cells no statistically significant difference for the ED50 was observed (38.36 vs. 31.56; P=0.454). Probit analysis of OTX-008 administration in HCA showed no dose-response-relation.

CONCLUSION
OTX-008 has antiproliferative effects on human glioblastoma cells independent of MGMT-promotor methylation status. The sensitivity of GBM cells to OTX-008 depends on the gal-1 expression level. In HCA no effect on cell viability was observed. OTX-008 seems a promising novel substance in glioblastoma therapy.
P11.46 Discovery of a new HDAC6 inhibitor for the treatment of glioblastoma
Authors: Auzmendi-Iriarte J , Saenz-Antoñanzas A , Andermatten J , Elua-Pinin A , Aldaba E , Vara Y , Matheu A 
Published: September 2019

Abstract

BACKGROUND
Glioblastoma’s origin and development is not only associated to genetic alterations, but also to epigenetic changes. Indeed, an altered expression or activity of epigenetic enzymes such as histone deacetylases (HDAC) has been associated to cancer stem cell activity, which has been widely described as a major feature for therapy resistance and tumor recurrence. In particular, inhibition of HDAC6 is an increasingly attractive pharmacological strategy, due to its association with low toxicity. Thus, the aim of the present study was to determine the impact of a new HDAC6-selective-inhibitor in glioblastoma and glioma stem cells.

MATERIAL AND METHODS
To test the effect of QTX compound in glioblastoma and glioma stem cell lines, cell viability after 72h of treatment was studied by MTT assay. After evaluation of IC50, QTX in vitro activity was analyzed, focusing on proliferation, apoptosis and stemness of U87-MG cell line and confirmed in a patient-derived glioma stem cell line. In vivo antitumor effect was evaluated using U87-MG cells xenografted in immunocompromised mice; after tumor formation, 5 mice were randomly selected as control group and another 5 for QTX treatment (intraperitoneal administration of 50 mg/kg; 5 days of dosing / 2 days off for 2 weeks). Mice weight was measured daily and tumor volume every two days.

RESULTS
We demonstrated that QTX reduces viability of all tested glioblastoma cells, even more greatly than normal astrocytes. Indeed, QTX diminishes proliferation and induces apoptosis in both conventional and patient-derived glioma cell lines. In particular, this effect was accompanied by a reduction of self-renewal properties of glioma stem cells. Interestingly, QTX in vitro activity was more effective comparing to the pan-inhibitor SAHA or the HDAC6-selective inhibitor Tubastatin A. Furthermore, QTX delayed tumor initiation and progression in vivo, without presenting significant side effects.

CONCLUSION
QTX compound presents a promising anti-tumor effect both in vitro and in vivo in glioblastoma, at least in part, inhibiting glioma stem cell activity.
P11.48 Dose-dependent effects of radiation exposure on the cell culture of glioblastoma G01, obtained from the patient with a long-term survival
Authors: Belyashova A , Golanov A , Pavlova G , Savchenko E , Antipina N , Panteleev D , Shamadykova D , Smirnov G , Nikolaeva A 
Published: September 2019

Abstract
Background: The predictors of a favorable prognosis regarding radiation exposure in patients with glioblastoma have not been studied enough, therefore, the search for factors determining a tumor response to the combined chemoradiation treatment is an actual task at present. DNA repair protein RAD51 homolog 1 (RAD51) is a crucial protein for homologous recombination and its inhibition has been shown to sensitize glioma stem cells to irradiation. Materials and Methods: G01 primary glioblastoma cell culture was obtained from tumor tissues from patient with long term survival (42 month).An irradiation with the energy of 6 MeV was carried out in 1 fraction 20,40,60,80,100,125,150,200,250 Gy with Linac. mRNA expression of the RAD51 gene, XRCC6, XRCC5 genes, relative amount of RAD51 protein and Ku70, Ku80 proteins, proliferative activity of cell culture was evaluated by RT-PCR, Western blotting, MTT-test, respectively.Results: When G01 cells were irradiated with doses from 5 to 180 Gy there was a uniform linear decrease in the population of proliferating cells compared to the control, but at a dose of 200 Gy a rise to 24% was observed. The mRNA expression of the RAD51 gene increased 2 times after irradiation at a dose of 20 Gy compared with control and then increased, reaching a peak at the level of 100,250 Gy. Minimal expression was observed after irradiation at a dose of 20 and also decreased at 200 Gy. The mRNA expression of the XRCC5 gene increased 2-fold after irradiation at a dose of 20 Gy compared with control and then decreased, remaining at the same level. Minimal expression was observed after irradiation at a dose of 200Gy. The relative amount of Ku80 protein reached a peak at a dose of 100 Gy, followed by a decrease. Maximum expression level of mRNA of the XRCC6 gene was observed after irradiation at a dose of 250Gy. The relative amount of Ku70 protein also decreased at 200 Gy and reached a peak at a dose of 250 Gy. Conclusions: After irradiation transplantable G01 cell culture from patient with long term survival a linear decrease in proliferative activity depending on the dose was observed with an decrease in mRNA expression of Rad51 gene and the relative amount of RAD51,Ku70 in dose level of 200Gy that could potentially indicate sensitivity point to radiation exposure in these cell culture. Further studies using cell cultures from patients may help in understanding the mechanisms of radioresistance and radiosensitivity in glioblastoma.The research was supported financially by RFBR (Project No. 18-29-01061).
P11.54 Identification of PDGFRA and MYC(N) as somatic driver genes in Glioblastoma
Authors: Berezovsky A D , Transou A , Irtenkauf S , Poisson L , Hank Wu K , Mikkelsen T , deCarvalho A 
Published: September 2019

Abstract

BACKGROUND
Somatic oncogene amplification happens frequently in glioblastoma (GBM). The second most frequently amplified gene encoding receptor tyrosine kinases in GBMs is platelet derived growth factor alpha (PDGFRA) (15%). In contrast, MYC and MYCN amplification occurs in 1.6% and 2.9%, respectively. Our goal was to characterize the role of PDGFRɑ and Myc in GBM.

MATERIAL AND METHODS
Neurosphere cultures were implanted in cohorts of 10–15 nude mice. 5 PDX lines, presenting median survival of 29–59 days were classified as short survivors, and 5 lines with median survival between 104–134 days classified as long survivors. Total RNA was extracted from PDX terminal tumors (3 biological replicates) and sequenced in a paired-end read format. Mouse reads were filtered out using Xenome. MYC and PDGFRA expression patterns were analyzed in tissue microarrays representing duplicated samples from 40 glioma neurosphere-derived PDX lines by IHC (1 anaplastic oligodendroglioma, 8 recurrent GBM with 2 newly diagnosed/recurrent pairs). Normalized staining intensity (MI) and area (A) were quantified using Fiji/ImageJ.

RESULTS
PDGFRA, MYC, MYCN gene amplifications were represented in a molecularly diverse panel of GBM patient-derived cancer stem-like cells (CSC) and orthotopic mouse xenografts (PDX). Transforming to a normal distribution (log10), 4/13 of cell lines had a PDGFRA mRNA expression (RPKM) higher than 1.5. Similarly, one PDX line had a staining index of greater than 10, 11 (27.5%) had an index between 5–10. The range of intra-tumoral variance, represented by standard deviation, was 0.09–24.25 highlighting the heterogeneity of PDGFRɑ expression. PDGFRɑ phosphorylation (Y754) did not differ between 8 cell lines cultured in NMGF, but deviated in alternate medias without growth factors, supplemented with FBS. In comparison, MYC(N) mRNA expression is only elevated in the context of a known amplification. Furthermore, a a MYC activity signature consisting of 18 target genes was only evident in the 5 amplified CSC lines. Taking advantage of genomic heterogeneity, we have isolated subclones lacking PDGFRA amplification from a PDGFRA amplified GBM CSC. The absence of PDGFRA amplification reduced the self-renewal potential to 37% of the PDGFRA amplified cell population (p=0.001) in clone 1 and 57% in clone 2 (p=0.013). Pertaining to determinants of in vivo survival, MYC was altered in 80% of short survivors (2/5 MYC, 2/5 MYCN amplification) and in 0% of long survivors. Myc signature was highly correlated with in vivo survival (Pearsons’ corr. = -0.77) and MYC gene expression was correlated with in vivo TMZ resistance (corr. = 0.7).

CONCLUSION
These results suggest that PDGFRɑ expression and activity can occur in the absence of gene amplification, while Myc activity is dependent on gene amplification. Both oncogenes drive oncogenic pathways that should be explored as therapeutic targets.