tbuckley/cabot-search huggingface dataset:
IMMU-12. TGFβ ACTIVATION BY RADIATION OPPOSES IMMUNE REJECTION OF INTRACRANIAL GL261
Authors: Mary Barcellos-Hoff, Alba Gonzalez-Junca, Denis Beckford Vera, Henry VanBrocklin, Benjamin Franc, Renate Parry
Journal: Neuro-Oncology (2018)

Enabling anti-tumor immunity in brain is a challenge due to its unique microenvironment that includes tissue-specific extracellular matrix, immune cells and vasculature, and because many glioblastoma patients require rapid treatment, usually surgery followed by radiation therapy, that may oppose immunotherapy. Here we hypothesize that transforming growth factor β (TGFβ) is at the root of the profoundly immunosuppressive tumor microenvironment, and is perpetuated by standard of care, radiation therapy. We first localized TGFβ activation in situ using GC1008, a humanized pan-isoform TGFβ neutralizing antibody, radiolabeled with 89Zr for PET-CT imaging. The antibody localized to a murine intracranial tumor compared to the injury-control brain injected with PBS. Paired comparisons of dual flank tumors in which one was irradiated (15 Gy) showed that radiation significantly increased 89Zr-GC1008 uptake (p0.0002). This was confirmed by immunostaining with an antibody that detects active TGFβ and nuclear pSMAD, indicative of signaling. Administration of TGFβ pan-isoform neutralizing antibody, 1D11 (25 mg/kg), to mice bearing irradiated intracranial tumors reduced immunostaining for active TGFβ and p-SMAD and blocked induction of a critical TGFβ target, tenascin-C, compared to treatment with isotype control antibody. These data support radiation-induction of TGFβ activation. Mice bearing i.c. GL261 (n=10–12) treated with 1D11 compared to isotype IgG had similar (17d vs 16d) median survival, which was doubled by tumor irradiation (10 Gy). Combined treatment with 1D11 and radiation led to durable control (Kaplan-Meier, p>0.0009), in which mice that showed complete regression by bioluminescence imaging for >45 days rejected a flank GL261 re-challenge. TGFβ inhibition with tumors treated with 5 daily 6 Gy fractions also eradicated most intracranial GL261. The undetectable brain bioluminescence and successful re-challenge suggest that TGFβ inhibition in the context of radiation can release the immunosuppressive microenvironment, elicit anti-tumor immunity and enable immune memory.
TMIC-52. DEXAMETHASONE-MEDIATED ACTIVATION OF FIBRONECTIN MATRIX ASSEMBLY INHIBITS DISPERSAL OF HUMAN PRIMARY GBM CELLS IN A MOUSE RETINA IN VIVO MODEL
Authors: Arthur Carminucci, Shabbar Danish, Ramsey Foty
Journal: Neuro-Oncology (2018)

Identifying drugs that can mitigate dispersal, particularly after patients undergo the Stupp protocol, may increase the length of time to radiological recurrence and improve overall survival. Previous studies have shown that Dexamethasone (Dex) treatment induces fibronectin matrix assembly (FNMA) and that this significantly reduces dispersal of primary human GBM (pGBM) cells in vitro and ex vivo. Here, we introduce an in vivo mouse retina dispersal assay to demonstrate that Dex also inhibits dispersal in vivo. Single cell dispersions of fluorescently-labeled pGBM cells were injected into mouse retinas along with soluble fibronectin, and mice were either treated with vehicle control or Dex at dose equivalents of 1mg-8mg/day for 5 days, whereupon mice were sacrificed and eyes removed and fixed in 4% PFA. Retinas were then extirpated, stained with Fn antibody and DAPI, mounted, and imaged by scanning laser confocal microscopy. z-stacks were collected and penetration distance assessed. 3-color images were generated for localization of pGBM cells, FNMA and DAPI. Additionally experiments were performed in the presence of Dex and either FUD fragment, an inhibitor of FNMA, or iii-11C control peptide. We show that Dex significantly reduces z-axis penetration of pGBM cells into mouse retina, that Dex treatment significantly alters the morphology of dispersal of injected pGBM cells within the x,y plane, that without Dex, the presence of fibronectin increases dispersal, that Dex treatment activates FNMA by pGBM cells leading to containment of the tumor mass, and that Dex-mediated activation of FNMA is fibronectin dose-dependent. Moreover, treatment with FUD but not iii-11C restores ability of tumor cells to disperse. Interestingly, dispersal inhibition could be achieved at Dex doses as low as 1mg/day. Our study defines a role for fibronectin as a facilitator of pGBM dispersal and Dex-mediated activation of FNMA as an inhibitor of that process.
CSIG-40. HETEROZYGOUS IDH1R132H/WT CREATED BY “SINGLE BASE EDITING” INHIBITS HUMAN ASTROGLIAL CELL GROWTH AND PROMOTES CELL MIGRATION
Authors: Shuang Wei, Jie Wang, Olutobi Oyinlade, Ding Ma, Shuyan Wang, Jiang Qian, Shuli Xia
Journal: Neuro-Oncology (2018)

Mutations in the isocitrate dehydrogenase 1 (IDH1) gene have been identified in a number of cancer types, including brain cancer. The Cancer Genome Atlas project has revealed that IDH1 mutations occur in 70–80% of grade II and grade III gliomas. Until recently, most of the functional studies of IDH1 mutations in cellular models have been conducted in overexpression systems with the IDH1 wild type background. In this study, we employed a modified CRISPR/Cas9 genome editing technique called “single base editing”, and efficiently introduced heterozygous IDH1 R132H mutation (IDH1R132H/WT) in human astroglial cells. Global DNA methylation profiling revealed hypermethylation as well as hypomethylation induced by IDH1R132H/WT. Global gene expression analysis identified molecular targets and pathways altered by IDH1R132H/WT, including cell proliferation, extracellular matrix, and cell migration. Our phenotype analysis indicated that compared with IDH1 wild type cells, IDH1R132H/WT promoted cell migration by up-regulating integrin b4 (ITGB4), and significantly inhibited cell proliferation. All these genotype and phenotype changes were reversed by mutant IDH1 inhibitor AGI-5198. Using our mutated IDH1 models generated by genome editing, we identified novel molecular targets of IDH1R132H/WT, namely Yes-associated protein (YAP) and its downstream signaling pathway Notch, to mediate the cell growth-inhibiting effect of IDH1R132H/WT. In summary, the “single base editing” strategy has successfully created heterozygous IDH1 R132H mutation that recapitulates the naturally occurring IDH1 mutation. Our isogenic cellular systems that differ in a single nucleotide in one allele of the IDH1 gene provide a valuable model for novel discoveries of IDH1R132H/WT-driven biological events.
COMP-05. EVALUATION OF A DEEP LEARNING ARCHITECTURE FOR MRI PREDICTION OF IDH, 1p19q AND TERT IN GLIOMA PATIENTS
Authors: Panagiotis Korfiatis, Daniel Lachance, Ian Parney, Jan Buckner, Jeanette Eckel-Passow, Paul Decker, Robert Jenkins, Margaret Wrensch, John Wiencke, Helen Hansen, Terri Rice, Lucie McCoy, Sarah Nelson, Jennifer Clarke, Jennie Taylor, Tracy Luks, Bradley Erickson
Journal: Neuro-Oncology (2018)

Recent studies have highlighted the importance of using molecular biomarkers (IDH, 1p19q, TERT) to group gliomas that have similar clinical behavior, response to therapy, and outcome. An emerging hypothesis is that glioma specific genetic and/or molecular alterations manifest as specific observable changes in MR anatomical imaging. Morphologic and texture features, originating from anatomical MRI, have been investigated as imaging biomarkers to predict MGMT and glioma group status. These texture or morphologic based approaches pose several challenges including requirements for several preprocessing steps such as intensity standardization, skull stripping, and tumor segmentation. Deep learning is an important evolving technology in many different fields, including anatomic imaging, and can be used to empirically identify important features in a variety of modalities, including MRI. Importantly deep learning precludes the need for extensive pre-processing. We describe a convolutional neural network, evaluating resnet50, vgg16, inception and xception neural network architectures, that can predict IDH, 1p19q and TERT status utilizing conventional T2 weighted MRI imaging with intensity normalization and nonuniform intensity normalization (N4) bias corrections. The dataset consisted of 432 images (340 for training and 92 for validation) from patients published by Eckel-Passow et al New England Journal of Medicine (2015). The system achieved a weighted f1 score of 0.901, 0.937 and 0.924 for IDH, 1p19q and TERT prediction on the test dataset, respectively. IDH status was misclassified in 9 out of 92 patients, while 1p19q and TERT status was misclassified in 6 and 7 patients respectively. Our results demonstrate the potential of deep learning architectures applied to conventional MRI to predict molecular glioma groups.
RTHP-08. RE-EVALUATING THE SEQUENCING OF RADIOTHERAPY AND CHEMOTHERAPY IN PEDIATRIC MEDULLOBLASTOMA
Authors: Clayton Hess, Beow Yeap, Jay Sahasakmontri, Miranda Lawell, Elizabeth Weyman, Sara Gallotto, Benjamin Bajaj, Kira Sieger, Shannon MacDonald, Karen Marcus, Mark Kieran, Mary Huang, Nancy Tarbell, David Ebb, Torunn Yock
Journal: Neuro-Oncology (2018)

Standard treatment for medulloblastoma in children over age 3 includes resection and radiotherapy, followed by chemotherapy. Some studies have found disease control decrements if chemotherapy was delivered before radiotherapy. However, these studies recommended radiation interruptions for hematologic toxicity, which were more severe in children receiving chemotherapy prior to craniospinal radiotherapy. We report outcomes of pediatric medulloblastoma patients treated post-operatively with radiotherapy-first (RT1) or chemotherapy-first CT1). POPULATION/ 206 patients age 2–23 years with medulloblastoma were treated with proton radiotherapy from May 2000 to December 2016. We analyzed the effect of sequencing radiotherapy first (n=164) or chemotherapy first (n=42) after surgery on event-free (EFS) and overall survival (OS) controlling for known risk factors. Median follow-up was 5.8 years. Children who received CT1 sequencing were younger (p<0.0001), more likely to receive high-dose chemotherapy (p<0.001), have high/intermediate risk disease (p<0.0001), M1-M3 stage (p<0.001), and large-cell/anaplastic histology (p=0.04). M1-M3 stage (p=0.01), high/intermediate risk disease (p=0.03), and anaplastic/large-cell histology (p=0.04) were all predictive of worse EFS. Despite higher proportions of risk factors in the CT1 cohort, 5-year EFS and OS in the RT1 versus CT1 groups were no different at 89% versus 84% (p=0.39) and 90% versus 84% (p=0.33), and remained equivalent when controlling for M1-M3 stage and unfavorable histology (p=0.86). Radiation treatment duration was equivalent at a median of 43 days (RT1) and 42 days (CT1) (p=0.4). Children with anaplastic/large-cell histology had lower EFS only in the RT1 cohort (64% vs. 87%, p=0.01) and equivalent EFS in the CT1 cohort (73% vs. 78%, p=0.88), suggesting a possible benefit to high-dose chemotherapy before RT in children with unfavorable histology. CONCLUSIONS: Disease control and overall survival were equivalent in the radiotherapy-first and chemotherapy-first cohorts when radiation treatment times were minimized.
TMIC-16. CORE-LIKE TUMOR CELLS PROMOTE MALIGNANCE OF GLIOBLASTOMA VIA INTERCELLULAR CROSSTALK WITH EDGE-LIKE TUMOR CELLS IN A HDAC1-CD109 DEPENDENT MANNER
Authors: Hai Yu, Marat S Pavlyukov, Mutsuko Minata, Suojun Zhang, Soniya Bastola, James Markert, Krishna Bhat, Maode Wang, Ichiro Nakano
Journal: Neuro-Oncology (2018)

Glioblastoma (GBM) is a malignant primary brain cancer without cure, due to the edge infiltrating tumor cells and non-complete resection. Although intratumoral heterogeneity is recognized in various cancers including GBM, its spatial distribution and intercellular crosstalk remain poorly understood. Previously, we identified two mutually exclusive glioma stem-like cells (GSCs) subtypes in GBM, termed mesenchymal (MES) and non-MES GSCs. Here, we tested the hypothesis that non-MES and MES GSCs have inter-cellular crosstalk to promote GBM aggressiveness and heterogeneity. We found that MES GSCs are preferentially located in the tumor core region, while non-MES GSCs subside in the tumor edge. Co-culture with MES GSC-containing cultures (glioma spheres) promoted both in vitro growth and in vivo tumorigenicity of non-MES ones. By a high throughput screening, several HDAC inhibitors selectively eliminated MES glioma spheres, while preserving non-MES glioma spheres. Among the HDAC family, HDAC1 is upregulated in GBM and associated with unfavorable outcome. Knockdown of HDAC1 blocked the intercellular pro-tumorigenic signal from MES glioma spheres to the non-MES counterparts. Mechanistically, CD109 is secreted from MES glioma spheres, thereby contributing intercellular pro-tumorigenic signals from MES to non-MES spheres. By RNA sequence, we found that HDAC1 regulates transcriptional activity of CD109 via binding to the promoter of CD109 together with the MES-specific transcription factor C/EBPb. To validate the intercellular signals in a single tumor, we established 6 clones of spheres from both tumor core and edge derived from the same GBM patient. The core lines contained those with higher resistance to irradiation (IR) treatment in comparison to the edge-derived counterparts. Furthermore, the core glioma spheres that showed higher MES signature promoted the growth and transformation of the non-MES like edge-derived glioma spheres both in vitro and in vivo. Collectively, our data identified HDAC1-CD109 dependent intercellular crosstalk from core like MES GCSs to edge like non-MES GSCs.
Associations Between Breast Cancer Survivorship and Adverse Mental Health Outcomes: A Systematic Review
Authors: Helena Carreira, Rachael Williams, Martin Müller, Rhea Harewood, Susannah Stanway, Krishnan Bhaskaran
Journal: JNCI Journal of the National Cancer Institute (2018)

We aimed to systematically review the evidence on adverse mental health outcomes in breast cancer survivors (≥1 year) compared with women with no history of cancer.
CMET-19. CLINICAL RISK ASSESSMENT SCORE TO ESTIMATE THE LIKELIHOOD OF PSEUDOPROGRESSION VERSUS TUMOR GROWTH FOLLOWING STEREOTACTIC RADIOSURGERY FOR BRAIN METASTASES
Authors: Bente Skeie, Per Øyvind Enger, Paal-Henning Pedersen, Geir Olve Skeie
Journal: Neuro-Oncology (2018)

A major challenge in the follow-up of patients managed with stereotactic radiosurgery (SRS) brain for metastases (BM) is to differentiate pseudoprogression (PP) from tumor recurrence (TR). A clinical score based on tumor and treatment related factors would be valuable when selecting appropriate treatment. Follow-up images of 97 consecutive patients treated with SRS for 406 BM were analyzed. We included 100 (24.6 %) BM in 42 (43.3 %) patients which responded either with TR (delayed growth; 53 (13.1 %) BM in 27 patients) or PP (temporary volume increase; 47 (11.6 %) BM in 15 patients). Differences between the 2 groups were analyzed and used to develop a PP risk assessment score (PP-RAS). Significant factors associated with a higher incidence of PP versus TR were: primary lung cancer vs. other primaries, BM volume < 2cc (or BM < 1.5 cm in diameter), Target cover ratio ≥ 98 % and prior radiation with SRS or WBRT. Based on the presence (0) or not (1) of these 5 parameters, a risk assessment score for PP versus TR was established. A PP-RAS score of 0 corresponds with high risk of PP vs.TR, whereas a score of 5 corresponds low risk of PP vs. TR. A score of ≤ 1 point was associated with 100 % PP, 2 points with 57 % PP and 43 % TR, 3 points with 57 % TR and 43 % PP whereas ≥ 4 points were associated with 84 % TR and 16 % PP, π=24.57, df =4, p < 0.001). Based on these 5 parameters at the time of SRS our risk assessment score could robustly differentiate between PP versus growth following SRS. The score is user-friendly and may be a useful tool to guide the decision making whether to retreat or observe at appropriate follow-up intervals.
IMMU-66. A NOVEL METABOLITE TO INCREASE EFFICACY OF CELLULAR IMMUNOTHERAPY IN THE TREATMENT OF GLIOBLASTOMA
Authors: Farhad Dastmalchi, Aida Karachi, Alexander Vlasak, Hassan Azari, Usma Baban, Duane Mitchell, Maryam Rahman
Journal: Neuro-Oncology (2018)

Immune cell migration is critical for cellular immunotherapy efficacy in the treatment of glioblastoma (GBM). Sarcosine is a non-toxic metabolite that is associated with a migratory phenotype in prostate cancer cells. We utilized sarcosine to increase migration of dendritic cells (DC) and T cells to increase efficacy of cellular immunotherapy. HYPOTHESIS: Sarcosine increases cellular migration and will improve tumor outcomes when combined with cellular immunotherapy platforms in the treatment of GBM. DC and T cell migration was evaluated in vitro using transwell plates and in vivo using flowcytometry and immunofluorescence microscopy. The impact of sarcosine loaded cells on tumor outcomes was measured by testing a DC vaccine platform in the treatment of murine tumor models. Genomic expression of cytokines on sarcosine treated cells was tested using RT-PCR. Cells were efficiently loaded with sarcosine by simply adding sarcosine to the culture media (20mM). DCs and T cells loaded with sarcosine demonstrated increased migration in vitro (p<0.0001). Mice treated with DC vaccination in the setting of sarcosine demonstrated significantly increased DC migration to draining lymph nodes and spleens (p<0.05). Gene expression analysis demonstrated that sarcosine caused upregulation of cytokines (IFNg,Xcl1,Fasl,Csf2,CCL19,Bmp2,IFNa2 and IL27) and downregulation of other cytokines (Ccl22,IL1b,Cxcl3,Ccl5,IL9 and IL18)(p<0.05). Vaccination with sarcosine loaded OVA-DCs led to increased proliferation of antigen specific T cells compared to regular OVA-DC vaccination (p<0.05). B16F10-OVA tumor bearing animals treated with sarcosine loaded OVA-DC vaccines had significantly reduced tumor growth and prolonged survival compared to animals treated with OVA-DC vaccines without sarcosine (p<0.0001). Sarcosine loaded DC vaccines resulted in suppressed tumor growth and improved survival in a murine model. These effects are partially mediated by changes in cytokine expression in sarcosine loaded DCs. Further experiments testing sarcosine loaded T cells and the mechanism of increased migration in sarcosine loaded immune cells are underway.
GENE-11. SMALL TERMINAL ALTERATIONS AND ALTERNATIVE LENGTHENING OF TELOMERES ARE A FEATURE OF IDH-MUTANT, 1p/19q NON-CODELETED GLIOMAS
Authors: Desmond Brown, Seiji Yamada, Corinne Praska, Thomas Kollmeyer, Joshua Jacobs, Paul Decker, Matt Kosel, Alissa Caron, Chandralekha Halder, Vanessa Ruiz, Benjamin Kipp, Jesse Voss, Rachel Vaubel, Caterina Giannini, Robert Jenkins
Journal: Neuro-Oncology (2018)

Gliomas are typified by genetic variability and instability. The full potential of molecular genetics to classify tumors has not been realized. We previously proposed a novel glioma classification system that increases the sensitivity and specificity of diagnosis and improve prognostication. We have completed copy number array mutational analyses and a targeted next-generation sequencing 50-gene glioma panel on 148 Mayo Clinic formalin-fixed paraffin-embedded gliomas with subsequent data validation performed on 419 gliomas from the TCGA. Median age at resection was 49 years (range: 17–80; 95% 46.5–51.6 years). There were 36 (24.3%) IDH-mutant, 1p/19q codeleted oligodendrogliomas; 46 (31.1%) IDH-mutant, 1p/19q non-codeleted astrocytomas and 66 (44.6%) IDH-wildtype gliomas. Small terminal alterations (STAs) defined as copy number variations (CNVs) IDH-mutant, 1p/19q non-codeleted tumors. Acquisition of 32 STAs was observed in 47% IDH-mutant, 1p/19q non-codeleted versus 27% IDH-wildtype tumors (P=1.8x10-5). In the TCGA dataset, these were seen in 67% versus 26% respectively (P=2.8x10-16). STAs were glioma subclass-specific and did not correlate with overall genetic instability as determined manually or with a computational method. ATRX loss was observed in 27 of 41 (65.9%) tumors with an ATRX mutation versus 20 of 106 (18.9%) ATRX-wildtype tumors (P=1.3x10-7). ATRX loss also correlated with the alternative lengthening of telomeres (ALT) phenotype and was seen in 25 of 31 (80.6%) ALT-positive versus 7 of 55 (12.7%) ALT-negative tumors (P=1.5x10-9). STAs were present in 19 of 32 (59.4%) ALT-positive cases and 8 of 35 (22.9%) ALT-negative cases (P=0.0061). IDH-mutant, 1p/19q non-codeleted astrocytomas have a high prevalence of STAs. This is associated with ATRX loss and the ALT. These alterations do not appear to have de novo implications for survival but may provide novel diagnostic tools and therapeutic targets.
ACTR-28. PHASE 1 DOSE ESCALATION TRIAL OF THE SAFETY OF BMX-001 CONCURRENT WITH RADIATION THERAPY AND TEMOZOLOMIDE IN NEWLY DIAGNOSED PATIENTS WITH HIGH-GRADE GLIOMAS
Authors: Katherine Peters, John Kirkpatrick, Ines Batinic-Haberle, Mary Affronti, Sarah Woodring, Deborah Iden, Sujata Panta, Eric Lipp, Patrick Healy, James Herndon, Ivan Spasojevic, Sara Penchev, Shayne Gad, David Siberstein, Margaret Johnson, Dina Randazzo, Annick Desjardins, Henry Friedman, David Ashley, James Crapo
Journal: Neuro-Oncology (2018)

BMX-001 (MnTnBuOE-2-PyP5+) is a metalloporphyrin with differential action in response to oxidative stress caused by radiation therapy (RT)and chemotherapy, both critical components in the treatment of high-grade gliomas (HGG). In preclinical studies, BMX-001 functions as a radioprotectant of normal tissue, for example protection of central nervous system white matter and radiosensitizer of human glioblastoma (GBM) xenografts. Therefore, we underwent a phase 1 study to evaluate safety of BMX-001 in newly diagnosed patients with HGG receiving concurrent RT and temozolomide (TMZ). We performed a phase 1, single-center, dose-escalation study of BMX-001 in combination with concurrent RT (daily fractions of 1.8–2 Gy given 5 days/week for 6 weeks for a total of 59.4–60 Gy) and TMZ (75 mg/m2 daily X 42 days). We administered BMX-001 as a subcutaneous injection at a loading dose before start of RT and TMZ and then subsequently 2 times/week for 8 weeks. Primary endpoint was determination of the maximum tolerated dose (MTD). We assessed safety using National Cancer Institute Common Terminology Criteria for Adverse Events 4.03. We enrolled 15 subjects with GBM (WHO grade IV) with age range of 19 to 80 years. BMX-001 at 42 mg loading dose and 20 mg subsequent dose was the maximum administered dose and 28 mg loading dose and 14 mg subsequent dose was the MTD. Sinus tachycardia (grade 3) was the dose-limiting toxicity at 42 mg loading dose (n=1). Only other related grade ≥ 3 event seen was hypotension (grade 3) (n=1). Most common related toxicity was grade 1 injection site reaction (n=7). BMX-001 with RT plus TMZ and post-RT TMZ for patients with newly diagnosed HGG was safe and well-tolerated. Phase II study with BMX-001 in combination with concurrent RT and TMZ in subjects with newly diagnosed HGG is planned.