bluuebunny/crossref_metadata_2025_split huggingface dataset:
DNAR-15. POLYMORPHISM AT P21 CODON 31 PROVIDED A PREDICTION FOR BEVACIZUMAB THERAPY IN GLIOBLASTOMA MULTIFORME
Authors: Cheng Wen-Yu , Shen Chiung-Chyi , Chiao Ming-Tsang 
Published: November 2022

Abstract
Glioblastoma (GBM) is a common, malignant brain tumor. While it rarely metastasizes to distant organs, the diffuse invasion of glioma cells within the brain makes it difficult to resect. P21 (Waf-1) is a cyclin-dependent kinase inhibitor that plays an essential role in cell growth arrest, terminal differentiation, and apoptosis. Thus, the existence of natural variants of p21 could be linked to specific cancer. The purpose of this study was to identify the polymorphism variants of p21 codon 31 (Ser31Arg) and to explore its role in the therapy of glioblastoma multiforme. A total of unrelated 99 GBM subjects, were enrolled in the study, and genomic DNA was obtained from each tumor sample for genotyping. Genotyping was performed by polymerase chain reaction (PCR) restriction fragment length polymorphism method (PCR-RFLP analysis. Odds ratios (Ors) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression analysis. We found that among these GBM patients, the distribution of codon 31 polymorphisms was 20.2% for Serine homozygotes (Ser/Ser), 32.3% for arginine homozygotes (Arg/Arg), and 47.5% for Serine/arginine heterozygotes (Ser/Arg). Although the polymorphisms of p21 codon 31 were not directly associated with the overall survival of GBM, both the Arg/Arg and Arg/Ser genotypes were associated with significant benefits in terms of overall survival in patients treated with CCRT plus bevacizumab compared to patients treated with CCRT alone. Our findings suggest that the p21 Ser31Arg polymorphism may play an important role in the pathogenesis and initiation of GBM. Moreover, the polymorphism seems to contribute to a significant prediction at early diagnosis for bevacizumab therapy.
SURG-42. MOLECULAR PROFILE CONSENSUS CLUSTERING DEFINES CLINICALLY DISTINCT GROUPS IN IDH WILD-TYPE GLIOBLASTOMA
Authors: Gersey Zachary , Mallela Arka , Zhang Xiaoran , Pease Matthew , Abdelhakiem Mohamed , Pearce Thomas , Lieberman Frank , Mantica Megan , Phillips Richard , Bagley Stephen , Nasrallah MacLean , Binder Zev , Brem Steven , Chen Isaac , O’Rourke Donald M , Zinn Pascal , Siddiqui Zaid , Amankulor Nduka 
Published: November 2022

Abstract

OBJECTIVES
Although the impact of surgery in glioblastoma (GBM) is well-established, there is insufficient data to determine how surgical resection affects overall survival (OS). The impact of other GBM genomic alterations on EOR-induced survival remains poorly understood. Here, we leverage a large cohort of GBM patients with genomic data to establish the impact of genomic alterations on resection-dependent overall survival in GBM.

METHODS
537 IDH WT GBMs from UPMC were analyzed using Glioseq next generation sequencing panel. Using molecular profiles derived from Glioseq data, semi-supervised Monte Carlo reference-based consensus clustering was used to define 5 distinct groups. Cox Proportional Hazards models were used to identify predictors of OS within molecular groups.

RESULTS
Clustering of 537 IDH wild-type GBM identified 5 distinct groups: 1: TERT mutated/MGMT methylated/EGFR mutated or gain; 2: TERT mutated /MGMT methylated/p53 mutated; 3: TERT WT; 4: TERT mutated/MGMT methylated/CDKN2A loss; 5: TERT mutated/MGMT unmethylated. Thresholds in postoperative residual contrast enhancing volume (rCEV) and residual non-contrast enhancing volume (rNCEV) were identified which marked significant differences in median overall survival (MOS) between molecular groups in rCEV -Group 1: 11.7cc, Group 2: 14.4cc, Group 3: 1.1cc, Group 4: 0.1cc, and Group 5 1.1cc. Sex, age, KPS &gt;70, temozolomide, and radiation along with thresholded rCEV and rNCEV were used in multivariate Cox analyses. Groups demonstrated distinct predictors of OS: radiation only in Group 1 tumors, low rCEV in Group 2 tumors, younger age, temodar, low CEV, and KPS &gt;70 in Group 3 tumors, female sex, younger age, radiation, KPS &gt;70 low rCEV in Group 4 tumors, and KPS &gt;70, temodar, and low rCEV in Group 5 tumors.

CONCLUSIONS
Clustering results suggest that there are clinically distinct molecular groups of IDH wild-type glioblastomas. Age, sex, KPS &gt;70, temozolomide treatment, radiation therapy, and EOR have varying affects on these molecular groups.
STEM-03. MOLECULAR PROFILING OF PRIMARY VERSUS RECURRENT GLIOBLASTOMA BRAIN TUMOR STEM CELLS UNCOVERS SIGNALING MECHANISMS THAT PROMOTE THE AGGRESSIVENESS OF RECURRENT GLIOBLASTOMA
Authors: Heemskerk Kyle , Hao Xiaoguang , Cseh Orsolya , Luchman H Artee , Weiss Samuel 
Published: November 2022

Abstract
Glioblastoma (GBM) is a devastating brain cancer with a median overall survival of a mere 12-15 months. Patients receive the standard of care treatment, comprised of maximum surgical resection, ionizing radiation, and temozolomide chemotherapy, however the tumor inevitably recurs. Recurrent GBM is more invasive, difficult to resect, and treatment resistant. GBM brain tumor stem cells (BTSCs), a sub-population of stem-like tumor cells with the ability to self-renew and differentiate into a heterogeneous tumor, are thought to be at the root of recurrent disease. BTSCs isolated from primary and recurrent tumors from the same patient are rare due to fewer resections of recurrent tumors and reduced quality of recurrent tumor samples used to initiate cell lines. As a result, the process of tumor recurrence is vastly understudied in BTSCs. To further understand the process of recurrence and elucidate potential mechanisms of invasion and treatment resistance, we explored global transcriptomics in 40 primary versus 17 recurrent BTSC cultures. Additionally, we profiled changes at the chromatin level in a subset of primary versus recurrent BTSCs using ATAC sequencing. Several pathways were found to be upregulated in recurrent GBM BTSCs, including innate immune signaling at the mRNA and chromatin level, which may mediate the aggressive nature of recurrent BTSCs. Moreover, these signaling changes may be unique to the stem cell population within the tumor, as they are not observed when profiling primary versus recurrent bulk tumors. We are currently targeting these pathways genetically and pharmacologically in primary and recurrent GBM BTSCs established from the same patient and have uncovered mechanisms for treatment resistance, invasion, and recurrence. Our work investigating global signaling changes in primary versus recurrent BTSCs holds promise for uncovering new therapeutic targets or biomarkers for treatment of recurrent GBM.
STEM-08. MODELING AND UNDERSTANDING GLIOBLASTOMA EDGE CELLS
Authors: Maturi Naga Prathyusha , Neves Ines , Dang Yonglong , Yildirim Irem , Latini Francesco , Bergström Tobias , Sundström Anders , Xing Pengwei , Jarvius Malin , Larsson Rolf , Fryknäs Mårten , Ryttlefors Mats , Chen Xingqi , Swartling Fredrik , Uhrbom Lene 
Published: November 2022

Abstract
Glioblastoma is a devastating disease with an overall median survival of 8 months from diagnosis. The majority of patients die of a tumor relapse in close proximity of the resected primary tumor. Glioblastoma is intensely researched but most studies have been performed on tissues and cultures derived from the bulk tumor while it is the remaining edge cells that cause lethality. Investigations of edge cells are rare and few experimental models exist. Here we have established and analyzed a series of matched cell cultures derived from the tumor bulk and outer edge of six IDH wildtype glioblastoma patients with the purpose to understand glioblastoma edge cell biology. Tumor samples were resected guided by 5-ALA fluorescence using neuro-navigation and stringent procedures to not contaminate edge samples with bulk tumor cells. First bulk tumor samples were resected from 5-ALA fluorescent tissue. After removal of all fluorescent areas and careful irrigation of the cavity the edge sample was resected 1-2 cm outside of the fluorescent border in a non-eloquent area. Following dissociation the samples were used in sphere assays and for explantation. There was a significant difference in self-renewal across all patients between matched bulk and edge cultures, in line with results from sphere assays on acute cells, suggesting maintenance of glioblastoma cell properties in established cultures. Invasion analysis showed a reverse significant difference between matched bulk and edge cultures strengthening a general functional distinction between tumor bulk and edge cells across patients. To investigate the molecular basis of our findings we performed whole exome sequencing (WES) and combined single cell RNA- and ATAC-sequencing (10X Multiome). Analyses are ongoing but WES data does not support genetic causes for their differences while the 10X Multiome data indicate that epigenetic regulation may underlie the different properties of bulk and edge glioblastoma cells.
STEM-16. MACROH2A2 REPRESSES AN EPIGENETIC SELF-RENEWAL NETWORK IN GLIOBLASTOMA STEM CELLS
Authors: Nikolic Ana , Bobyn Anna , Maule Francesca , Ellestad Katrina , Paik Seungil , Marhon Sajid , Mehdipour Parinaz , Lun Xuequng , Johnston Michael , Gafiuk Christopher , Zemp Franz , Shen Yaoqing , Ninkovic Nicoletta , Labit Elodie , Berger N Daniel , Brownsey Duncan , Kelly John , Biernaskie Jeff , Dirks Peter , Derksen Darren , Jones Steven J M , Senger Donna L , Chan Jennifer , Mahoney Douglas J , de Carvalho Daniel , Gallo Marco 
Published: November 2022

Abstract
Glioblastoma is a highly malignant tumour driven by a subset of self-renewing cells termed glioblastoma stem cells. This self-renewal phenotype is largely epigenetically driven, however, the exact epigenetic mechanisms underpinning it are poorly understood. We found that the histone variant macroH2A2 is repressed in a subset of glioblastoma tumours, and that this repression is associated with poorer survival. We interrogate the function of macroH2A2 using in vitro and in vivo patient-derived models. We show that macroH2A2 antagonizes self-renewal and expression of NPC and OPC-like markers, and rewires accessible chromatin by maintaining accessibility at a subset of enhancer elements. We identify small molecules that can upregulate macroH2A2 expression, and find that treatment with a small molecule reduces self-renewal, induces interferon sensitive genes, and a viral mimicry response, effects which are abolished by macroH2A2 knockdown. In summary, we identify macroH2A2 as a repressor of self-renewal in glioblastoma and suggest it may be a novel biomarker and potential marker of therapeutic susceptibility.
STEM-18. EPIGENETIC AND MOLECULAR COORDINATION BETWEEN HDAC2 AND SMAD3-SKI IS REQUIRED FOR GROWTH AND STEM CELL CHARACTERISTICS OF BRAIN TUMOUR STEM CELLS
Authors: Bahia Ravinder , Hao Xiaoguang , Hassam Rozina , Cseh Orsolya , Bozek Danielle , Luchman H Artee , Weiss Samuel 
Published: November 2022

Abstract
Brain tumour stem cell population in glioblastoma (GBM) display key cancer stem cell characteristics of high self-renewal and drug resistance that are maintained by the coordinated functions of epigenetic and molecular regulators. Yet, specific epigenetic mechanisms that, in collaboration with relevant molecular pathways, help maintain a stem-like state in BTSCs remain poorly understood. Here, we identify HDAC2 as a foremost epigenetic regulator in BTSCs that specifically utilizes the transforming growth factor-β (TGF-β) pathway related proteins, SMAD3-SKI, for remodelling BTSC chromatin accessibility and transcriptional programs to facilitate their stemness and tumorigenic potentials. Our initial drug screening revealed that selective inhibition of HDAC1 and 2 with romidepsin was effective in targeting BTSC viability, cell proliferation and self-renewal in vitro. Using CRISPR-cas9 knockout and shRNA knockdown strategies, we further demonstrated that loss of HDAC2 disrupts an epigenetic and molecular coordination between HDAC2 and SMAD-SKI proteins, which negatively impacts BTSC survival, cell proliferation and self-renewal in vitro and improves median survival in orthotopic xenograft mouse models. Loss of HDAC2 showed reduction in the protein abundance of transcriptional regulator, SMAD3 and negative regulator protein, SKI. However, overexpression of SMAD3 in HDAC2 deficient BTSCs could partially rescues their cell functional deficits. These findings suggest that context-specific epigenetic regulations by HDAC2 and its interaction with the critical transcriptional regulators, SMAD3-SKI, maintains the stemness and growth characteristics of BTSCs. Further HDAC2 overexpression increases cell proliferation and self-renewal abilities in normal neural stem cells (NSCs). These findings thus support the role of HDAC2 as a key epigenetic determinant of stemness in normal NSCs and of cancer stem cell characteristics and tumorigenic potential in BTSCs. Collectively, our data raises the potential that disruption of the coordinated mechanisms regulated by HDAC2-SMAD3-SKI axis may be an effective therapeutic approach for targeting GBM BTSCs.
STEM-21. REPURPOSING CLEMASTINE TO SUPPRESS GLIOBLASTOMA STEM CELLS
Authors: Sun Michael , Yang Rui , Liu Heng , Wang Wenzhe , Song Xiao , Hu Bo , Reynolds Nathan , Roso Kristen , Chen Lee , Greer Paula , Cheng Shi-Yuan , Ashley David , Pirozzi Christopher , He Yiping 
Published: November 2022

Abstract
Glioblastoma stem cells (GSCs), also known as brain tumor initiating cells (BTICs), drive tumor progression, heterogeneity, and resistance to treatments, posing formidable challenges to advancing effective treatments against glioblastoma (GBM). We postulated that inducing BTIC differentiation can serve as a solution to diminishing their stem-like features. Here, we report that clemastine, an over-the-counter oral medication for allergy relief, attenuates stemness and proliferation of BTICs. These effects of clemastine were accompanied by altered transcriptional programs suggestive of a shift from maintaining stem cell identity to differentiation, resonating with the ability of clemastine to promote oligodendrocyte precursor cell (OPC) differentiation to mature oligodendrocytes. Genetic perturbation and small-molecule inhibition of putative pharmacological targets of clemastine revealed that Emopamil-binding protein (EBP), an enzyme in the sterol biosynthesis pathway, played a pivotal role in mediating the differentiating and anti-tumor effects of clemastine. Notably, loss-of-function assays showed that EBP expression was indispensable for BTIC propagation. In contrast, overexpression of EBP stimulated BTIC proliferation, thus uncovering a previously unknown role of sterol metabolism in BTIC maintenance. Finally, we demonstrated that a mouse neural stem cell-derived glioma model was similarly susceptible to clemastine treatment. Taken together, our study identifies pathways essential for the perpetuation of stemness in GBM, and implicates a non-oncology drug with a well-established safety profile that can be repurposed to mitigate the stem-like properties of GBM.
STEM-23. SLOW CYCLING CELL RNA BASED T CELL THERAPY TO PREVENT RECURRENCE IN GBM
Authors: Dajac Mariana , Conforti Cole , Tian Guimei , Moore Ginger , Flores Catherine , Huang Jianping , Mitchell Duane , Deleyrolle Loic 
Published: November 2022

Abstract
Glioblastoma (GBM), the most common primary malignancy of the central nervous system (CNS), is almost universally fatal due to inevitable recurrence despite aggressive therapeutics. Considering the infiltrative nature of GBM, targeting residual cells after surgical tumor resection is challenging. Development of effective novel adjuvant therapies against drivers of disease recurrence is of imperative priority. Anticancer treatments most effectively eliminate rapidly dividing cells but spare dormant or infrequently dividing populations. Multiple studies have reported in numerous cancers the existence of slow-cycling cells (SCCs) that are refractory to therapies. Our laboratory identified SCCs in high-grade glioma, which represents an enriched reservoir of highly infiltrative and treatment-resistant cancer propagating cells known to drive recurrence. An effective approach to specifically eliminate this cell population is urgently required to limit recurrence and improve survival. Importantly, these cells reliably defined a cellular niche characterized by definite potentially immunogenic neoantigens, which can serve as immune targets. Our ultimate goal is to leverage the power of adoptive cellular therapy (ACT) to recognize GBM SCC-derived antigens to achieve robust tumor control through targeting of these critical drivers of recurrence. Our data revealed that dendritic cells electroporated with slow-cycling cell RNA successfully primed T cells to recognize and target glioma treatment resistant cells. These experiments demonstrated that slow cycling cell-specific T cells (SCC-T cells) exhibit enhanced activation when in presence of treatment-resistant tumor cells as shown by increased CD8 differentiation, amplified effector and memory differentiation compared to total tumor RNA-specific T cell and control groups. Additionally, SCC-T cells presented the highest anti-tumor activity, as demonstrated by the greatest decrease of tumor cell proliferation and increase of T cell apoptosis. Together these results demonstrate the efficacy and superiority of SCC-based immunotherapy platform to target treatment-resistant glioblastoma cells.
CCRG-02. THE DIFFUSE MIDLINE GLIOMA MUTATIONS, H3.3 K27M AND G34R/V, INHIBIT MITOTIC PHOSPHORYLATION OF SERINE 31, LEADING TO TUMOR FORMATION THROUGH INCREASED CHROMOSOMAL INSTABILITY
Authors: Day Charles , Grigore Florina , Langfald Alyssa , Hakkim Faruck , Daniels David , Vaughan Kevin , Robinson James , Hincliffe Edward 
Published: November 2022

Abstract
Diffuse midline gliomas (DMG) are high-grade pediatric gliomas that frequently harbor heterozygous histone H3.3 K27M, G34R, or G34V mutations. These mutations alter histone methylations, although the precise mechanism(s) of gliomagenesis remains uncertain. H3.3 contains a unique Serine at position 31 that is phosphorylated in prophase and dephosphorylated in anaphase during normal cell division. In an aberrant division, chromosome missegregation triggers S31 phosphorylation along chromosome arms in anaphase leading to p53-induced cell cycle arrest. Here we show in vitro and in vivo, that H3.3 K27M, G34R, and G34V significantly suppress S31 phosphorylation by Chk1 (the mitotic S31 kinase). In diploid cells, overexpression of H3.3 K27M, G34R, G34V, or non-phosphorylatable S31A significantly increases the frequency of chromosome missegregation, while H3.3 K36M did not. This missegregation phenotype could be rescued by overexpression of K27M/S31E or G34R/S31E double mutants. Next, we used genome editing to revert K27M or G34V patient-derived DMG cells to WT or replace the mutant allele with S31A. Reversion to WT increased metaphase S31 phosphorylation and reduced chromosome missegregations, but inserting an S31A mutation caused more mitotic defects. Following a mitotic error, newly formed aneuploid cells overexpressing K27M, G34R, or G34V suppress p53 levels and continue to divide, while WT overexpressing cells always arrest. To test the effects of diminished S31 phosphorylation on gliomagenesis, we utilized a novel mouse model of DMG. Expression of PDGFβ linked to H3.3K27M, H3.3G34R, and H3.3S31A in neural stem cells in vivo promoted the development of high-grade gliomas in under 100 days, whereas PDGFβ-H3.3WT did not. Notably, the S31A tumors had histologically normal levels of K27me3 and K36me3. This work shows that a single DMG-associated point mutation in H3.3 can generate chromosomal instability and suggests that chromosomal instability is a major contributing factor to DMG K27-altered and DMG G34-altered tumor formation.
CSIG-02. FOSL1 PROMOTES GLIOMA STEM CELLS TRAITS THROUGH INTERACTING WITH ITS BINDING PROTEIN PHOSPHORYLATED STAT3
Authors: Go Shanchun , King Pendelton , Liu Mingli 
Published: November 2022

Abstract

BACKGROUND
Glioma stem cells (GSCs) have key roles in tumorigenesis, progression, and resistance to conventional treatments for glioblastoma. We reported that TRPM7 channels, which fused with C-terminal kinase, endow glioma cells with stem cell-like capacities of self-renewal. Here, we investigated the role of TRPM7 downstream target gene FOSL1’s post transcription in glioma stemness.

METHODS
1) The immunohistochemical staining for FOSL1 was performed using the rabbit polyclonal anti-FOSL1 antibody in glioma tissue arrays from 76 Chinese patients and 10 normal individuals. The staining intensity of cells in TMA was evaluated in three different fields (≥100 cells/field). The semi-quantitative HSCORE was calculated for FOSL1. 2) Upon suppression of FOSL1 by siRNA FOSL1, GSC markers, CD133 expression was evaluated by flow cytometry using PE anti-human CD133 antibody, while ALDH1 enzymatic activity was assessed using an Aldefluor kit, in A172 and U87MG glioma cell lines and patient-derived xenoline PDX-L14 of proneural subtype. 3) To assay FOSL1 gene promoter activity, the 5’-flanking region of the human FOSL1 gene (1201bp) was inserted into the firefly luciferase reporter vector pGL3-Basic between MluI and BglII sites. For mutant construct, STAT3 binding sites were mutated using Q5 site-directed mutagenesis kit.

RESULTS
1) Quantification of the IHC results showed that FOSL1’s positive nuclear staining was significantly higher in GBM (n=13, p=0.0005), grade III (n=12, p=0.0116), and grade II astrocytoma (n=51, p=0.0485) compared to that of normal brain tissue (n=10). 2) GSC markers CD133 and ALDH1 were positively associated with FOSL1 in glioma. 3) Phosphorylated STAT3 directly binds to the FOSL1 promoter and the activation levels of STAT3 have a positive effect on the transcriptional activity of FOSL1.

CONCLUSION
Our results demonstrated the role of TRPM7-regulated STAT3 activation directly regulated FOSL1 gene transcription, which shed new light on TRPM7/FOSL1-directed therapeutics in glioma. (This study was supported by NIH NIGMS GM121230)