Central Nervous System Malignancies Research Articles

The safety and efficacy of bevacizumab in treatment of recurrent low-grade glioma: a systematic review and meta-analysis.

Central nervous system (CNS) tumors are among the most common malignancies in various age ranges. Low-grade glioma (LGG) can account for nearly 30% of pediatric CNS malignancies. Progression or recurrence after the first-line treatments is common among these patients. Therefore, more treatments are required. Bevacizumab as an anti-VEGF antibody has come into the spotlight recently and is especially used in relapse or recurrence settings. This review aims to study the safety and efficacy of bevacizumab for patients with recurrent LGG. This study was conducted according to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses. PubMed, Scopus, Web of Science, and Embase were comprehensively searched using the relevant key terms until 24th August 2023 to retrieve the studies that investigated clinical outcomes of bevacizumab in patients with recurrent LGG. All statistical analysis was performed by STATA v.17. A total of 1306 papers were gathered, out of which 13 were incorporated in the meta-analysis. The pooled incidence rate of treatment according to the RANO scale was 70% (95% CI = 43-98%) for objective response rate, 26% (95% CI = 58-96%) for partial response, 21% (95% CI = 15-28%) for minor response, 14% (95% CI = 3-24%) for complete response, 48% (95% CI = 37-59%) for stable disease, and 8% (95% CI = 4-11%) for progressive disease. Furthermore, according to progressive survival after treatment, it was 4% (95% CI = -1 to 9%) for 6-month PFS, 41% (95% CI = 32-50%) for 2-year PFS, and 29% (95% CI = 22-35%) for 3-year PFS. According to the RANO scale and PFS, clinicians should be aware that Bevacizumab could be a favorable alternative therapy for recurrent LGG. Furthermore, bevacizumab exhibits minimal toxicity and high tolerability in recurrent LGG.

Glioblastoma: a comprehensive approach combining bibliometric analysis, Latent Dirichlet Allocation, and HJ-Biplot : Glioblastoma insights and trends: a 49-year bibliometric analysis.

Glioblastoma is a common and aggressive malignant central nervous system tumor in adults. This study aims to evaluate and analyze the scientific results, collaboration countries, main research topics, and topics over time reported about glioblastoma. A bibliometric analysis of glioblastoma publications was performed mainly using R and Multbiplot software for author, journal, and resume. Associated statistic methods Latent Dirichlet Allocation (LDA) and HJ-Biplot. Inclusion criteria were research articles from the PubMed database published in English between 1973 and December 2022. A total of 64,823 documents with an annual growth rate of 8.27% indicates a consistent increase in research output over time. The results for the number of citations and significant publications showed Cancer Res, J Neuro-Oncol, and Neuro-Oncology are the most influential journals in the field of glioblastoma. The countries that concentrated research were the tumor United States, China, Germany, and Italy. Finally, there has been a marked growth in studies on prognosis and patient survival, therapies, and treatments for glioblastoma. These findings reinforce the need for increased global resources to address glioblastoma, particularly in underdeveloped countries. Glioblastoma research's exponential growth reflects sustained interest in early diagnosis and patient survival.

The importance of basic and translational research in caring for children with malignant solid tumors in Latin America.

Basic and translational research in pediatric cancer are essential to improve patient care. To critically assess the developments achieved in these areas in Latin America, we systematically reviewed information published between 2013 and 2023. Studies of basic and translational research performed by investigators in Latin America evaluating pediatric malignant solid and central nervous system tumors were retrieved from PubMed. Original articles published in English between 2013 and 2023 were included. Collaborations among Latin American authors or among Latin American authors working with researchers from other continents were also included. Studies were excluded if they focused only on adults or on basic research in tumor biology not specifically related to the tumor types analyzed in this review. A total of 550 articles were retrieved, but after removal of duplicates, 514 articles were included in the analysis, the majority of which were authored by researchers affiliated with institutions in Argentina, Brazil and Mexico. These countries also had the highest number of collaborations on original articles published with authors from Europe and North America. Argentina had the highest number of collaborations on original publications, with coauthors from Brazil and Uruguay. The median impact factor of the 244 journals in which articles were published was 3.5. The most commonly studied tumors were osteosarcomas, neuroblastomas and medulloblastomas; the most commonly studied areas were molecular analysis, tumor cell biology and biomarkers. In Latin America, research in pediatric oncology is on the agenda, despite a notable disparity in publication rates and frequency of collaboration between countries. There is a need to strengthen scientific collaboration within Latin America and with countries from other continents to promote research and to develop novel treatment strategies that reflect the local needs of children in Latin America who have solid tumors and brain cancer.

The Relationship Between the Molecular Phenotypes of Brain Gliomas and the Imaging Features and Sensitivity of Radiotherapy and Chemotherapy

Gliomas are the most common primary malignant tumors of the brain, accounting for about 80% of all central nervous system malignancies. With the development of molecular biology, the molecular phenotypes of gliomas have been shown to be closely related to the process of diagnosis and treatment. The molecular phenotype of glioma also plays an important role in guiding treatment plans and evaluating treatment effects and prognosis. However, due to the heterogeneity of the tumors and the trauma associated with the surgical removal of tumor tissue, the application of molecular phenotyping in glioma is limited. With the development of imaging technology, functional magnetic resonance imaging (MRI) can provide structural and function information about tumors in a noninvasive and radiation-free manner. MRI is very important for the diagnosis of intracranial lesions. In recent years, with the development of the technology for tumor molecular diagnosis and imaging, the use of molecular phenotype information and imaging procedures to evaluate the treatment outcome of tumors has become a hot topic. By reviewing the related literature on glioma treatment and molecular typing that has been published in the past 20 years, and referring to the latest 2020 NCCN treatment guidelines, summarizing the imaging characteristic and sensitivity of radiotherapy and chemotherapy of different molecular phenotypes of glioma. In this paper, we briefly review the imaging characteristics of different molecular phenotypes in gliomas and their relationship with radiosensitivity and chemosensitivity of gliomas.

A review of natural products and small-molecule therapeutics acting on central nervous system malignancies: Approaches for drug development, targeting pathways, clinical trials, and challenges.

In 2021, the World Health Organization released the fifth edition of the central nervous system (CNS) tumor classification. This classification uses histopathology and molecular pathogenesis to group tumors into more biologically and molecularly defined entities. The prognosis of brain cancer, particularly malignant tumors, has remained poor worldwide, approximately 308,102 new cases of brain and other CNS tumors were diagnosed in the year 2020, with an estimated 251,329 deaths. The cost and time-consuming nature of studies to find new anticancer agents makes it necessary to have well-designed studies. In the present study, the pathways that can be targeted for drug development are discussed in detail. Some of the important cellular origins, signaling, and pathways involved in the efficacy of bioactive molecules againstCNS tumorigenesis or progression, as well as prognosis and common approaches for treatment of different types of brain tumors, are reviewed. Moreover, different study tools, including cell lines, in vitro, in vivo, and clinical trial challenges, are discussed. In addition, in this article, natural products as one of the most important sources for finding new chemotherapeutics were reviewed and over 700 reported molecules with efficacy against CNS cancer cells are gathered and classified according to their structure. Based on the clinical trials that have been registered, very few of these natural or semi-synthetic derivatives have been studied in humans. The review can help researchers understand the involved mechanisms and design new goal-oriented studies for drug development against CNS malignancies.

Molecular characterization and survival analysis of a cohort of glioblastoma, IDH-wildtype

Glioblastoma, IDH-wild type, the most common malignant primary central nervous system tumor, represents a formidable challenge in clinical management due to its poor prognosis and limited therapeutic responses. With an evolving understanding of its underlying biology, there is an urgent need to identify prognostic molecular groups that can be subject to targeted therapy. This study established a cohort of 124 sequential glioblastomas from a tertiary hospital and aimed to find correlations between molecular features and survival outcomes. Comprehensive molecular characterization of the cohort revealed prevalent alterations as previously described, such as TERT promoter mutations and involvement of the PI3K-Akt-mTOR, CK4/6-CDKN2A/B-RB1, and p14ARF-MDM2-MDM4-p53 pathways. MGMT promoter methylation is a significant predictor of improved overall survival, aligned with previous data. Conversely, age showed a marginal association with higher mortality. Multivariate analysis to account for the effect of MGMT promoter methylation and age showed that, in contrast to other published series, this cohort demonstrated improved survival for tumors harboring PTEN mutations, and that there was no observed difference for most other molecular alterations, including EGFR amplification, RB1 loss, or the coexistence of EGFR amplification and deletion/exon skipping (EGFRvIII). Despite limitations in sample size, this study contributes data to the molecular landscape of glioblastomas, prompting further investigations to examine these findings more closely in larger cohorts.

Abstract LB200: Defining the mechanisms of cancer specific transcription factor, tGLI1

Abstract Glioblastoma (GBM) is the most common malignant central nervous system tumor in adults with a five-year survival rate of less than 7%. First identified in GBM, truncated GLI1 (tGLI1), an alternative splicing isoform of GLI1, has emerged as a cancer specific GLI1 variant as tGLI1 is highly expressed in both GBM cell lines and primary specimens but not in normal tissue. Despite an in-frame loss of 41 amino acids, the tGLI1 protein has retained all known GLI1 functional domains and appears to respond to sonic hedgehog in a similar manner as GLI1. However, tGLI1 operates as a gain of function transcription factor with the ability to bind to and activate genes unique from GLI1 to promote invasion, migration, angiogenesis, and stemness in both GBM and breast cancer. Despite the advancements in our understanding of tGLI1, a genome wide DNA binding pattern of tGLI1 has not been established and the mechanism by which tGLI1 gains access to these genes is unknown. To establish a more robust understanding of the differential DNA binding patterns of GLI1 and tGLI1, we carried out ChIP-sequencing (ChIP-seq) and found only 14% of GLI1 and tGLI1 binding sites are shared. These results suggest GLI1 and tGLI1 have even more unique binding pattens across the entire genome that previously thought. However, the underlying mechanism for why GLI1 and tGLI1 bind different regions of the genome remains elusive. To determine whether variations in protein interactions of GLI1 and tGLI1 contribute to the unique binding pattern of tGLI1, we carried out immunoprecipitation (IP) followed by mass spectrometry (mass spec). Results identified 45 GLI1 associated proteins and 52 tGLI1 associated proteins with only a 29% overlap between the two. Furthermore, gene ontology analysis revealed 43% of the tGLI1-specific associated proteins are involved in processes related to RNA binding, processing, and metabolism. From these RNA-related proteins, we validated an interaction between tGLI1 and the protein NONO. NONO, which can bind both RNA and DNA, is involved in a range of molecular processes including paraspeckle formation and transcriptional regulation. In GBM, high NONO expression correlated with poor patient outcomes and the mesenchymal subtype. Interestingly, we observed that NONO, along with another essential paraspeckle component, SFPQ, had a greater interaction with tGLI1 compared to GLI1. Furthermore, co-expressing NONO with tGLI1 significantly increased clonogenic growth as well as CD44 gene transactivation using a luciferase reporter, suggesting it may play a role in tGLI1-driven stem-like properties. Furthermore, co-expression of NONO and tGLI1 increased the nuclear localization of both proteins. Together, these results show NONO may enhance tGLI1 nuclear localization, transcriptional activity, and exacerbate tGLI1-driven phenotypes. These effects of NONO could also contribute to the differential binding pattern between GLI1 and tGLI1. Citation Format: Haddie DeHart, Nolan Gregg, Richard Carpenter. Defining the mechanisms of cancer specific transcription factor, tGLI1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB200.

AZD1390, an ataxia telangiectasia mutated inhibitor, attenuates microglia-mediated neuroinflammation and ischemic brain injury.

Excessive neuroinflammation mediated mainly by microglia plays a crucial role in ischemic stroke. AZD1390, an ataxia telangiectasia mutated (ATM) specific inhibitor, has been shown to promote radio-sensitization and survival in central nervous system malignancies, while the role of AZD1390 in ischemic stroke remains unknown. Real-time PCR, western blot, immunofluorescence staining, flow cytometry and enzyme-linked immunosorbent assays were used to assess the activation of microglia and the release of inflammatory cytokines. Behavioral tests were performed to measure neurological deficits. 2,3,5-Triphenyltetrazolium chloride staining was conducted to assess the infarct volume. The activation of NF-κB signaling pathway was explored through immunofluorescence staining, western blot, co-immunoprecipitation and proximity ligation assay. The level of pro-inflammation cytokines and activation of NF-κB signaling pathway was suppressed by AZD1390 invitro and invivo. The behavior deficits and infarct size were partially restored with AZD1390 treatment in experimental stroke. AZD1390 restrict ubiquitylation and sumoylation of the essential regulatory subunit of NF-κB (NEMO) in an ATM-dependent and ATM-independent way respectively, which reduced the activation of the NF-κB pathway. AZD1390 suppressed NF-κB signaling pathway to alleviate ischemic brain injury in experimental stroke, and attenuated microglia activation and neuroinflammation, which indicated that AZD1390 might be an attractive agent for the treatment of ischemic stroke.

PSMC2 promotes glioma progression by regulating immune microenvironment and PI3K/AKT/mTOR pathway

BackgroundGlioma, the most frequent and malignant central nervous system (CNS) cancer, has a bad outcome. Proteasome 26S subunit ATPase 2 (PSMC2) is an essential part of the 26S proteasome and promotes the development of several tumors. However, the pathway and function of PSMC2 in glioma have not been unelucidated. MethodsThis study analyzed PSMC2 expression in glioma tissues and its predictive significance for patients. We examined the link between PSMC2 and DNA methylation, immune cell infiltration, tumor immune cycle, immune cell homeostasis, and immune checkpoints. Subsequently, immunohistochemistry and in vitro trials were employed to validate the expression, prognostic potential, and function of PSMC2 in glioma. The mechanisms of PSMC2 in glioma were further explored. ResultsOur study revealed that PSMC2 expression increased in glioma tissues contrasted with healthy tissues, and patients with high PSMC2 glioma exhibited poor overall survival (OS) compared to the low-PSMC2 group. Immune profile analysis revealed that PSMC2 was positively related to immunosuppressive cell infiltration and immune checkpoints and adversely related to the cancer immune cycle and immune cell homeostasis. In cell-based investigations, the inhibition of PSMC2 was found to effectively suppress the aggressiveness and proliferation of glioma cell lines while also enhancing cell cycle arrest and promoting cell death. Gene Set Enrichment Analysis (GSEA), Gene Set Variation Analysis (GSVA), and in vitro experiments showed that PSMC2 promoted glioma development through the PI3K/AKT/mTOR pathway. ConclusionsPSMC2 was upregulated in glioma and promoted cancer progression by modulating the tumor immune microenvironment, cancer cell biological behavior, immune cell homeostasis, and the PI3K/AKT/mTOR pathway, providing a new option to treat glioma.

Abstract 1108: The impact of adjuvant radiotherapy (ART) and survival prediction by machine learning in intracranial hemangiopericytoma (HPC)

Abstract Background: Intracranial HPC is a rare brain tumor that accounts for less than 1% of all primary central nervous system malignancies. Surgery is the primary treatment, and while radiation may reduce the risk of local recurrence, its overall effectiveness remains uncertain. Therefore, it is crucial to develop reliable predictions for personalized care and improved management. In this study, we used machine learning (ML) techniques to predict the survival of patients with intracranial HPC. Methods: Data were obtained from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2019). Patients with other malignancies or lack of pathological diagnosis were excluded. T-tests and chi-square tests compared variables, while Kaplan-Meier, log-rank tests, and Cox regression identified prognostic factors for overall survival (OS) and cancer-specific survival (CSS). Patient records were randomly divided into training (80 %) and validation (20 %) sets. Univariate Cox regression and least absolute shrinkage and selection operator were used to identify the significant factors linked to survival, which were used to establish a nomogram for predicting the 3- and 5-year OS and CSS. Results: Of the 367 included patients, 121 underwent surgery and 246 underwent surgery + ART. The median survival time was 54 months. Patients who underwent surgery had 5-year OS rates of 61% and 86% for CSS, while those treated with surgery + ART had 81% and 96% survival rates, respectively. The two treatment groups showed significant differences in the OS and CSS (p<0.022 and p<0.017, respectively). Age ≥ 50 years was a poor prognostic factor for OS, whereas ART, localized stage and regional stage were good prognostic factors. No significant factors were associated with CSS. To construct the OS Nomogram, three predictors, age, stage, and treatment method, were chosen. In the training and validation sets, the C-indices are 0.799 and 0.736, respectively. The receiver operating characteristic curves (AUCs) for the 3- and 5-year OS in the training set were 0.594 and 0.617, respectively, whereas those in the validation set were 0.56 and 0.59. For the CSS nomogram, two factors, age and stage, were utilized. The C-indices for the training and validation sets are 0.814 and 0.774, respectively. In the training set, the AUCs for 3- and 5-year CSS were 0.585 and 0.605, respectively, and 0.563 in the validation set. The most important risk factor was the distant stage, while the most important protective factor was age less than 50 years. Conclusion: This study shows that ART has a significant impact on the treatment of Intracranial HPC and provides better survival outcomes. ML has been used to create prediction models to support personalized patient care. These findings provide valuable insights into the management of this rare brain tumor and the potential of data-driven approaches to improve treatment and outcomes. Citation Format: Sakhr Alshwayyat, Anas Alaa Al-Khalili, Ayah Erjan, Haya Kamal, Tala Abdulsalam, Mustafa Alshwayyat. The impact of adjuvant radiotherapy (ART) and survival prediction by machine learning in intracranial hemangiopericytoma (HPC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1108.

Abstract 5666: Exploring spatially resolved intra-tumoral heterogeneity of glioblastoma and neuronal mechanisms facilitating brain invasion

Abstract Glioblastoma (GBM) is a highly lethal brain cancer, comprising about half of all central nervous system malignancies. Its recurrence and resistance to aggressive treatments, such as surgery, radiation, and chemotherapy, underscore its biological complexity. A key feature of GBM is intra-tumoral heterogeneity (ITH), stemming from a diversity of transcriptional cell states within the tumor. While genetic contributions to ITH are well-researched, the role of non-genetic factors, especially in promoting transitions between the various transcriptional cell states (referred to as plasticity), is less understood. This plasticity enables GBM cells to survive treatment pressures, necessitating a deeper dive into the epigenetic underpinnings that govern it and the role of the tumor microenvironment (TME) in influencing it. We proposed that the TME significantly impacts the epigenetic landscape of both malignant and surrounding non-malignant cells, thereby promoting ITH and cell state plasticity. To assess this, we analyzed samples from different anatomical areas of GBM tumors collected using MRI-guided selection. Utilizing advanced multimodal single-cell sequencing technologies, we profiled the transcriptomes and epigenomes of individual cells, revealing their spatially dependent phenotypic and epigenetic diversity. Our results indicated a higher enrichment of progenitor-like malignant cells, resembling neural or oligodendrocyte progenitors, around the tumor margins. In contrast, the core mainly contained differentiated cells with mesenchymal-like characteristics. Intriguingly, progenitor-like cells in the peri-tumoral zone expressed a unique neuronal activity program, including elevated levels of PRC2 complex targets, which are critical for maintaining the pluripotency and self-renewal capabilities of neural stem cells. Additionally, our analysis of cell-cell interactions between neurons and malignant cells identified ligand-receptor pairs crucial for axon guidance, neurogenesis, and tumor invasion. Proneural factors, critical for neural differentiation, were more accessible in peri-tumoral progenitor-like cells, suggesting that malignant cells might exploit neurodevelopmental routes for growth and invasion. This work underscores the significant spatial cellular heterogeneity of GBM and the variation in epigenetic states across the tumor, demonstrating how GBM cells can hijack neurodevelopmental pathways to foster invasion. Although surgical resection can target the tumor core, our insights into the invasive mechanisms of malignant cells provide a foundation for developing targeted therapies to combat the highly invasive cells persisting in regions adjacent to the tumor. Citation Format: Federico Gaiti, Yiyan Wu, Sheila Mansouri, Benson Wu, Yosef Ellenbogen, Xuyao Li, Parnian Habibi, Joan Kant, Pathum Kossinna, Sandra Ruth Lau Rodriguez, Gelareh Zadeh. Exploring spatially resolved intra-tumoral heterogeneity of glioblastoma and neuronal mechanisms facilitating brain invasion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5666.

Abstract 3331: Preclinical combination of ONC206 with radiotherapy and temozolomide in a GBM mouse orthotopic model

Abstract Glioblastoma multiforme (GBM) is the most common form of primary malignant brain tumor in adults. It is also the most aggressive and lethal. Standard of care therapy comprises maximal safe surgical resection followed by adjuvant alkylating agent temozolomide (TMZ) and radiotherapy (RT). There have only been five drugs and one device ever approved by the FDA for the treatment of GBM. The five-year survival rate for GBM patients has shown no notable improvement in the last three decades. We previously reported that the first-in-class imipridone small-molecule Dordaviprone (ONC201) decreases protein chaperone ClpX to unleash mitochondrial protease ClpP activity, integrated stress response and cell death. Preclinical combination of ONC201 (100 mg/kg weekly) with radiotherapy and Temozolomide in a GBM mouse orthotopic model results in reduced tumor burden and prolonged survival. The second generation imipridone ONC206 also activates integrated stress response and decreases ClpX in GBM cells but ONC206 is approximately 20 times more potent than its parent imipridone ONC201. ONC206 0.08 uM in combination with 12.5 uM TMZ and 2 Gy RT reduced the cell viability of GBM cells significantly compared to all single treatments and double treatments. During a short-term treatment of a GBM mouse orthotopic model, ONC206 (50 mg/kg weekly, half of ONC201 doses) synergizes with TMZ and RT to induce more tumor cell apoptosis and inhibits more tumor cell proliferation compared to other groups with single or double treatments. There are two ongoing clinical trials with ONC206: single weekly or multiple-day weekly dose regimens of single-agent, oral ONC206 in patients with recurrent, primary central nervous system (CNS) neoplasms (NCT04541082) and ONC206 alone or in combination with radiation therapy in treating patients with diffuse midline gliomas that is newly diagnosed or has come back (recurrent) or other recurrent primary malignant CNS tumors (NCT04732065). Future studies evaluating the role of immune function, mitochondrial metabolism, dopamine receptors, the ISR and TRAIL pathway in the synergistic effect would support further development of the triple combination regimen of ONC206, TMZ and radiation therapy for GBM clinical trial. Citation Format: Lanlan Zhou, Leiqing Zhang, Jun Zhang, Shengliang Zhang, Wafik S. El-Deiry. Preclinical combination of ONC206 with radiotherapy and temozolomide in a GBM mouse orthotopic model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3331.

Abstract 1174: Incorporation of multisector analysis into the design of personalized DNA vaccines for patients with newly diagnosed glioblastoma

Abstract Glioblastoma (GBM) is the most common malignant central nervous system (CNS) tumor in adults. Despite multimodality treatment including surgery, radiation, and chemotherapy, patients with GBM have a median survival of less than 2 years. Recent clinical trials have reported promising results using cancer vaccines to stimulate a tumor-directed immune response in several histologies. The majority of trials targeted tumor neoantigens derived from a single tumor sample, which limits the antigen pool in spatially heterogeneous cancers like GBM. Our group previously implemented multisector sequencing into the design of personalized peptide vaccines to increase the candidate pool of targetable neoantigens (NCT03422094). Although the peptide vaccine treatment was successful in stimulating an effector T cell response, it was limited by a long turnaround time from vaccine design to administration and a low peptide production rate. Therefore, we incorporated multisector sampling into the design of a personalized DNA-based GBM vaccine (NCT04015700). An average of 33% of the candidate targetable neoantigens were spatially restricted to a single sampled region, which would have been missed without multisector sequencing. DNA-based vaccines are potentially advantageous over peptide-based vaccines because they enable a higher neoantigen payload and faster manufacturing time with potent immunogenicity. Here, we report the results from 9 subjects enrolled onto the study. Spatially distinct tumor regions were subjected to whole exome sequencing (WES) and RNA-sequencing (RNA-seq), data from which were used to identify neoantigens through the pVACseq algorithm (http://pvactools.org). An average of 32 neoantigens were included in each DNA vaccine, compared to an average of only 9 for the peptide vaccine, and the turnaround time from date of surgery to administration of the DNA vaccine was about half the time. Three subjects had radiographic evidence of tumor progression prior to vaccination, highlighting the aggressive nature of GBM and the need for short manufacturing timeframes. PBMCs pre- and post-DNA vaccination were collected from 7/9 subjects. All subjects presented detectable responses and 6/7 tested revealed a sustained increment in T cell reactivity against tumor neoantigens post-treatment by IFN-γ ELISpot. Intracellular staining showed a neoantigen-specific antitumor CD8/CD4 T cell cytolytic (CD69+, CD107a+) and proliferative (Ki67+) profile. Post-vaccination tumor resections were performed for 2 subjects who also were treated with PD1 blockade upon progression, providing an opportunity to explore vaccine-induced changes in the tumor microenvironment. Herein, we demonstrate the advantages of incorporating multisector sequencing into the development of DNA-based GBM vaccines and provide insights into the resulting immune responses. Citation Format: Elizabeth A. Garfinkle, Katherine E. Miller, Alexandra J. Livingstone, Renzo Perales-Linares, Neil Cooch, Alfredo Perales-Puchalt, Sarah Rochestie, Joann Peters, Niranjan Y. Sardesai, William E. Gillanders, Elaine R. Mardis, Gavin P. Dunn, Tanner M. Johanns. Incorporation of multisector analysis into the design of personalized DNA vaccines for patients with newly diagnosed glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1174.

Adeno-associated virus-mediated trastuzumab delivery to the central nervous system for human epidermal growth factor receptor 2+ brain metastasis.

Trastuzumab improves overall survival for HER2+ breast cancer, but its short half-life in the cerebrospinal fluid (~2-4 days) and delivery limitations restrict the ability to target HER2+ central nervous system (CNS) disease. We developed an adeno-associated virus (AAV) vector expressing a codon-optimized, ubiquitin C (UbC)-promoter-driven trastuzumab sequence (AAV9.UbC.trastuzumab) for intrathecal administration. Transgene expression was evaluated in adult Rag1 knockout mice and rhesus nonhuman primates (NHPs) after a single intracerebroventricular (ICV) or intra-cisterna magna (ICM) AAV9.UbC.trastuzumab injection, respectively, using real-time PCR, ELISA, Western blot, in situ hybridization, single-nucleus RNA sequencing, and liquid chromatography-mass spectrometry; antitumor efficacy was evaluated in brain xenografts using HER2+ breast cancer cell lines (BT-474, MDA-MB-453). Transgene expression was detected in brain homogenates of Rag1 knockout mice following a single ICV injection of AAV9.UbC.trastuzumab (1 × 1011 vector genome copies [GC]/mouse) and tumor progression was inhibited in xenograft models of breast-to-brain metastasis. In NHPs, ICM delivery of AAV9.UbC.trastuzumab (3 × 1013 GC/animal) was well tolerated (36-37 days in-life) and resulted in transgene expression in CNS tissues and cerebrospinal fluid at levels sufficient to induce complete tumor remission in MDA-MB-453 brain xenografts. With AAV9's proven clinical safety record, this gene therapy may represent a viable approach for targeting HER2 + CNS malignancies.

Genetically Distinct Oligosarcoma Arising from Oligodendroglioma: Systematic Review & Illustrative Case Example

BackgroundOligosarcoma is a rare central nervous system (CNS) neoplasm that may arise following oligodendroglioma resection, which demonstrates a unique genetic profile and aggressive clinical phenotype. We present a systematic review and illustrative case example emphasizing the clinical and prognostic features of this unusual and unfavorable neuro-oncologic disease. MethodsSystematic literature review and illustrative case report. ResultsA 41-year-old man who had undergone two neurosurgical resections for a WHO grade II oligodendroglioma (Ki-67=5-10%, 1p/19q co-deleted, IDH2 mutated), without adjuvant chemoradiation, presented with seizures seven years after resection. An extra-axial mass was identified adjacent to the resection cavity, in which gross total resection was achieved. Pathology confirmed WHO grade IV oligosarcoma (Ki-67=20%). Adjuvant chemoradiation was initiated, with disease control observed over 6 months of follow-up.7 publications met inclusion criteria. Oligosarcoma has been confirmed in 36 lesions, arising in 35 patients; 5 were primary oligosarcoma, while 31 occurred in the setting of prior resected oligodendroglioma or oligoastrocytoma. Features shared by these lesions include re–gain of H3K27me3 expression, 1p/19q codeletion, homozygous deletion of CDKN2A/B, loss of 6q, loss of NF1 and YAP1, and attenuation of CpG island methylator (G-CIMP). Median survival after oligosarcoma diagnosis was 1.3 years (range, 0-5.2; n=35). ConclusionOligosarcoma is a prognostically unfavorable CNS neoplasm with characteristic imaging and pathologic features, and a strong association with previously resected oligodendroglioma. Aggressive treatment is recommended, including gross total resection and adjuvant chemoradiation. Further study is required to define optimal treatment protocol for this CNS malignancy.

Myeloid cells as potential targets for immunotherapy in pediatric gliomas.

Pediatric high-grade glioma (pHGG) including pediatric glioblastoma (pGBM) are highly aggressive pediatric central nervous system (CNS) malignancies. pGBM comprises approximately 3% of all pediatric CNS malignancies and has a 5-year survival rate of approximately 20%. Surgical resection and chemoradiation are often the standard of care for pGBM and pHGG, however, even with these interventions, survival for children diagnosed with pGBM and pHGG remains poor. Due to shortcomings associated with the standard of care, many efforts have been made to create novel immunotherapeutic approaches targeted to these malignancies. These efforts include the use of vaccines, cell-based therapies, and immune-checkpoint inhibitors. However, it is believed that in many pediatric glioma patients an immunosuppressive tumor microenvironment (TME) possess barriers that limit the efficacy of immune-based therapies. One of these barriers includes the presence of immunosuppressive myeloid cells. In this review we will discuss the various types of myeloid cells present in the glioma TME, including macrophages and microglia, myeloid-derived suppressor cells, and dendritic cells, as well as the specific mechanisms these cells can employ to enable immunosuppression. Finally, we will highlight therapeutic strategies targeted to these cells that are aimed at impeding myeloid-cell derived immunosuppression.

Cancer Type and Histology Influence Cutaneous Immunotherapy Toxicities: A Multi-Institutional Cohort Study.

Cutaneous immune-related adverse events (cirAEs) are the most common toxicities to occur in the setting of immune checkpoint inhibitor (ICI) therapy. Identifying patients who are at increased risk of developing cirAEs may improve quality of life and outcomes. To investigate the influence of cancer type and histology on the development of cirAEs in the setting of ICI therapy and survival outcomes. This retrospective cohort study included patients between December 1, 2011, and October 30, 2020. They received ICIs from 2011-2020 with follow-up of outcomes through October 2021. We identified 3,668 ICI recipients who were seen at Mass General Brigham and Dana-Farber. Of these, 669 developed cirAEs. Records that were incomplete or categories of insufficient sample size were excluded from the study cohort. Multivariate Cox proportional hazards models were utilized to investigate the impact of cancer organ system and histology on cirAE development, after adjusting for demographics, Charlson Comorbidity Index, ICI type, cancer stage at ICI initiation, and year of ICI initiation. Time-varying Cox proportional hazards modeling was utilized to examine the impact of cirAE development on mortality. Compared to other non-epithelial cancers (neuroendocrine, leukemia, lymphoma, myeloma, sarcoma, and central nervous system malignancies), cutaneous squamous cell carcinoma (cSCC) (HR = 3.57, p < 0.001), melanoma (HR = 2.09, p < 0.001), head and neck adenocarcinoma (HR = 2.13, p = 0.009), genitourinary transitional cell carcinoma (HR = 2.15, p < 0.001), and genitourinary adenocarcinoma (HR = 1.53, p = 0.037) were at significantly higher risk of cirAEs in multivariate analyses. The increased risk of cirAEs translated into an adjusted survival benefit for melanoma (HR = 0.37, p < 0.001) and cSCC (HR = 0.51, p = 0.011). The highest rate of cirAEs and subsequent survival benefits were observed in cutaneous malignancies treated with ICIs. This study improves our understanding of patients who are at highest risk of developing cirAEs and would, therefore, benefit from appropriate counseling and closer monitoring by their oncologists and dermatologists throughout their ICI therapy. Limitations include its retrospective nature and cohort from one geography.

Abstract TMP105: Development and Validation of a Risk Prediction Model for Ischemic Stroke Among Individuals Newly Diagnosed With Cancer

Introduction: Cancer is an emerging risk factor for ischemic stroke. The risk of stroke is highest during the first year after a new diagnosis of cancer, but no tools exist to identify which patients are at the highest risk.. Methods: Using linked clinical and administrative health databases, we conducted a population-based retrospective cohort study of adults in Ontario, Canada with newly diagnosed cancer from 2010 - 2021 (excluding non-melanoma skin cancer &amp; central nervous system malignancies). Patients were randomly selected for model derivation (60%) or validation (40%). The final model predicting stroke within 1 year following cancer diagnosis was derived using multivariable Fine-Gray regression with candidate predictors selected via backward elimination. Sub-distribution adjusted hazard ratios (aHR) and 95% confidence intervals (CI) were calculated, where all-cause mortality was treated as a competing event. Model performance of the validation cohort was assessed using the C-statistic &amp; calibration plots for discrimination and calibration, respectively. Results: Of the 698,566 eligible patients, 418,911 were randomly allocated to derivation, and 279,576 to validation. The overall rate of stroke per 1000 person-years was 6.7 (6.4 - 6.9) for the derivation cohort. The final model included 22 predictors: age, sex, long-term care residency, history of heart failure, hypertension, dementia, asthma, atrial fibrillation, dyslipidemia, liver disease, ischemic stroke, transient ischemic attack, valvular disease, venous thromboembolism, hospitalization within the last 3 months, cancer type, cancer stage, cancer surgery or chemotherapy 3 months following diagnosis, and several 2-way interactions with age &amp; cancer type. Discrimination was good, with a c-statistic of 0.73 in the validation cohort. The model was well calibrated, with points following the 45-degree line (Fig 1). Conclusion: We derived and validated a risk prediction model for ischemic stroke in patients with a new cancer diagnosis with good discrimination. Although our results require external validation, it has potential to identify individuals at highest risk for future randomized trials.

B7-H3 Inhibitors in Oncology Clinical Trials: A Review.

B7-H3 is a transmembrane receptor highly prevalent on malignant cells and plays an important role in adaptive immunity that is not fully elucidated. Targeted B7-H3 inhibitors, including antibody-drug conjugates, radioimmunotherapy, and monoclonal antibodies, are a new class of antineoplastic agents showing promising preliminary clinical efficacy, observed with several of these agents against multiple tumor types. Particularly promising treatments are enoblituzumab for prostate cancer, 131I-omburtamab for central nervous system malignancies, and HS-20093 for small-cell lung cancer but further studies are warranted. There are clinical trials on the horizon that have not yet enrolled patients examining chimeric antigen receptor T-cell therapies, bi- and tri-specific killer engagers, and dual-affinity retargeting proteins. These data will be telling of the efficacy of B7-H3 inhibitors in both hematologic and solid malignancies. This study aimed to compile available results of B7-H3 inhibitors in oncology clinical trials.

Brain Tumor Imaging in Adolescents and Young Adults: 2021 WHO Updates for Molecular-based Tumor Types.

Published in 2021, the fifth edition of the World Health Organization (WHO) classification of tumors of the central nervous system (CNS) introduced new molecular criteria for tumor types that commonly occur in either pediatric or adult age groups. Adolescents and young adults (AYAs) are at the intersection of adult and pediatric care, and both pediatric-type and adult-type CNS tumors occur at that age. Mortality rates for AYAs with CNS tumors have increased by 0.6% per year for males and 1% per year for females from 2007 to 2016. To best serve patients, it is crucial that both pediatric and adult radiologists who interpret neuroimages are familiar with the various pediatric- and adult-type brain tumors and their typical imaging morphologic characteristics. Gliomas account for approximately 80% of all malignant CNS tumors in the AYA age group, with the most common types observed being diffuse astrocytic and glioneuronal tumors. Ependymomas and medulloblastomas also occur in the AYA population but are seen less frequently. Importantly, biologic behavior and progression of distinct molecular subgroups of brain tumors differ across ages. This review discusses newly added or revised gliomas in the fifth edition of the CNS WHO classification, as well as other CNS tumor types common in the AYA population.