Publications by authors named "Keith L Ligon"

Background: Molecular features have been incorporated alongside histologic criteria to improve glioma diagnostics and prognostication. CDKN2A/B homozygous-loss associates with worse survival in IDH1/2-mutant astrocytomas (IDHmut-astrocytomas), the presence of which denotes grade 4 tumor independent of histologic features. However, no molecular features distinguish survival amongst histologically-defined grade 2 and 3 IDHmut-astrocytomas.

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Purpose: Radiation therapy may enhance anti-tumor immune responses by several mechanisms including induction of immunogenic cell death. We performed a phase 2 study of pembrolizumab with re-irradiation in patients with recurrent glioblastoma.

Methods: Sixty recurrent glioblastoma patients received pembrolizumab with re-irradiation alone (cohort A, bevacizumab-naïve; n=30) or with bevacizumab continuation (cohort B, n=30).

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Article Synopsis
  • Diffuse hemispheric gliomas, specifically H3G34R/V-mutant, are aggressive brain tumors with no current targeted therapies and come from neural precursor cells.
  • Researchers found that these tumors display developmental patterns similar to healthy brain interneurons and identified key genes that these tumor cells depend on, especially CDK6.
  • Targeting CDK6 with inhibitors showed promising results in reducing tumor growth and improving survival in experimental models, with one patient showing a significant response to treatment.
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  • - Histopathology image evaluation is crucial for cancer diagnosis, but traditional AI methods struggle with generalizing across different imaging protocols and sample populations due to their specialized nature.
  • - The Clinical Histopathology Imaging Evaluation Foundation (CHIEF) model is introduced as a general-purpose, weakly supervised machine learning framework designed to systematically evaluate cancer by extracting diverse imaging features through two complementary pretraining methods.
  • - CHIEF, trained on over 60,000 whole-slide images from various sites, demonstrated improved performance over existing deep learning approaches by up to 36.1%, showing its effectiveness in adapting to diverse samples and enhancing digital pathology evaluations for cancer patients.
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Background: Postoperative recurrence risk for pediatric low-grade gliomas (pLGGs) is challenging to predict by conventional clinical, radiographic, and genomic factors. We investigated if deep learning of MRI tumor features could improve postoperative pLGG risk stratification.

Methods: We used pre-trained deep learning (DL) tool designed for pLGG segmentation to extract pLGG imaging features from preoperative T2-weighted MRI from patients who underwent surgery (DL-MRI features).

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Unlabelled: We investigated the effectiveness of navtemadlin (KRT-232) in treating recurrent glioblastoma. A surgical window-of-opportunity trial ( NCT03107780 ) was conducted on 21 patients to determine achievable drug concentrations within tumor tissue and examine mechanisms of response and resistance. Both 120 mg and 240 mg daily dosing achieved a pharmacodynamic impact.

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Background: Velcrins are molecular glues that kill cells by inducing the formation of a protein complex between the RNase SLFN12 and the phosphodiesterase PDE3A. Formation of the complex activates SLFN12, which cleaves tRNA(TAA) and induces apoptosis. Velcrins such as the clinical investigational compound, BAY 2666605, were found to have activity across multiple solid tumor cell lines from the cancer cell line encyclopedia, including glioblastoma cell lines.

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  • A study examined how molecular features, clinical metrics, and treatment affect the overall survival of glioma patients amidst recent changes in classification and care standards.
  • The research involved analyzing 4,400 gliomas from various sources, finding that 27.2% had updated molecular classifications that differed from their initial diagnoses; survival rates varied significantly between different patient groups.
  • The study identified key prognostic factors for different glioma types and created survival prediction tools based on age, molecular features, and treatment, aiming to enhance understanding and research on gliomas.
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Background: The frequency and significance of IDH mutations in glioma across age groups are incompletely understood. We performed a multi-center retrospective age-stratified comparison of patients with IDH-mutant gliomas to identify age-specific differences in clinico-genomic features, treatments, and outcomes.

Methods: Clinical, histologic, and sequencing data from patients with IDH-mutant, grades 2-4 gliomas, were collected from collaborating institutions between 2013 and 2019.

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  • A study conducted at Dana-Farber/Boston Children's Cancer and Blood Disorders Center focused on classifying pediatric solid tumor diagnoses and analyzing genomic mutations to improve clinical trial design and treatment options.
  • Over 6.5 years, the research included 888 pediatric cancer patients, revealing that 33% had genomic variants that aligned with precision oncology trials, while 14% received targeted therapies.
  • The findings stress the significance of using genomic data for enhancing treatment strategies and the necessity for data sharing, particularly for addressing rare pediatric cancers in clinical settings.
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Cell density, the ratio of cell mass to volume, is an indicator of molecular crowding and therefore a fundamental determinant of cell state and function. However, existing density measurements lack the precision or throughput to quantify subtle differences in cell states, particularly in primary samples. Here we present an approach for measuring the density of 30,000 single cells per hour with a precision of 0.

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Over-activation of the epidermal growth factor receptor (EGFR) is a hallmark of glioblastoma. However, EGFR-targeted therapies have led to minimal clinical response. While delivery of EGFR inhibitors (EGFRis) to the brain constitutes a major challenge, how additional drug-specific features alter efficacy remains poorly understood.

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Background: Glutamatergic neuron-glioma synaptogenesis and peritumoral hyperexcitability promote glioma growth in a positive feedback loop. The objective of this study was to evaluate the feasibility and estimated effect sizes of the AMPA-R antagonist, perampanel, on intraoperative electrophysiologic hyperexcitability and clinical outcomes.

Methods: An open-label trial was performed comparing perampanel to standard of care (SOC) in patients undergoing resection of newly-diagnosed radiologic high-grade glioma.

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Wilms tumor (WT) is the most common renal malignancy of childhood. Despite improvements in the overall survival, relapse occurs in ~15% of patients with favorable histology WT (FHWT). Half of these patients will succumb to their disease.

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Article Synopsis
  • * Researchers used advanced RNA-sequencing techniques on tumor samples taken from patients after four weeks of IDHi treatment to examine cellular changes.
  • * Findings reveal that IDHi promotes differentiation of tumor cells toward a specific brain cell type (astrocytes), reduces stem-like cells, and highlights a mutation (NOTCH1) that may hinder this differentiation and affect treatment response.
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Purpose To develop and externally test a scan-to-prediction deep learning pipeline for noninvasive, MRI-based mutational status classification for pediatric low-grade glioma. Materials and Methods This retrospective study included two pediatric low-grade glioma datasets with linked genomic and diagnostic T2-weighted MRI data of patients: Dana-Farber/Boston Children's Hospital (development dataset, = 214 [113 (52.8%) male; 104 (48.

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Purpose: Adverse clinical events cause significant morbidity in patients with GBM (GBM). We examined whether genomic alterations were associated with AE (AE) in patients with GBM.

Experimental Design: We identified adults with histologically confirmed IDH-wild-type GBM with targeted next-generation sequencing (OncoPanel) at Dana Farber Cancer Institute from 2013 to 2019.

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  • Glioblastoma (GBM) is a challenging brain cancer with poor outcomes, and understanding its tumor microenvironment could improve treatment effectiveness.
  • The study adapts stereotactic biopsies to gather multi-omics data from GBM patients, revealing detailed insights into the tumor and immune response.
  • Results indicate that stereotactic needle biopsies can provide high-quality samples for comprehensive analysis, aiding in monitoring treatment responses and furthering research.
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A hallmark of high-risk childhood medulloblastoma is the dysregulation of RNA translation. Currently, it is unknown whether medulloblastoma dysregulates the translation of putatively oncogenic non-canonical open reading frames (ORFs). To address this question, we performed ribosome profiling of 32 medulloblastoma tissues and cell lines and observed widespread non-canonical ORF translation.

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Nuclear atypia, including altered nuclear size, contour, and chromatin organization, is ubiquitous in cancer cells. Atypical primary nuclei and micronuclei can rupture during interphase; however, the frequency, causes, and consequences of nuclear rupture are unknown in most cancers. We demonstrate that nuclear envelope rupture is surprisingly common in many human cancers, particularly glioblastoma.

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  • Antibody-drug conjugates (ADCs) are designed to deliver chemotherapeutic agents to specific cancer cells, and recent research shows that even low levels of target proteins like HER2 can lead to effective treatment in certain brain tumors.
  • A study analyzing gene expression data from over 500 CNS tumors revealed that various tumor types express different ADC targets, with ependymomas having high HER2 levels, while meningiomas and other tumors exhibited specific patterns of target protein expression.
  • The findings suggest that understanding the unique expression profiles of ADC targets in CNS tumors can guide future treatment strategies and help develop new therapies tailored for specific cancer types.
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