Investigation of tumor stem cell maintenance and cellular hierarchy in pediatric high-grade glioma

Document text

Principal Investigator: John A DeSisto
Organization: UNIVERSITY OF COLORADO DENVER
Fiscal Year: 2024
Award: $93,872
Funding agency: National Cancer Institute

Project Summary
The project’s overall goal is to determine important biological characteristics and investigate therapeutic 
options for pediatric high-grade gliomas (PHGG), the most aggressive of childhood central nervous system 
tumors and most common cause of childhood cancer mortality. PHGG survival rates are less than 5% for the 
subtype diffuse midline glioma and 20% for hemispheric histone 3-wild type (H3-wt) PHGG. PHGG are highly 
invasive and often grow diffusely among normal cells, limiting surgery as a therapeutic option. Radiation 
therapy (RT) is transiently effective, but the tumors nearly always recur. Despite hundreds of clinical trials, no 
chemotherapy has shown a definitive survival benefit in PHGG. Effective PHGG therapies are critically 
needed.
PHGG likely originates from stemlike tumor initiating cells (PICs). PHGG tumors comprise several 
distinct cell types of glial origin, in varying proportions. This tumor heterogeneity complicates understanding 
PHGG tumor biology and designing therapies. Aim 1 will investigate how each distinct cell type in PHGG 
contributes to overall tumorigenesis in a mouse model. Single-cell RNA-Seq (scRNA-Seq) analysis of 
orthotopic patient derived PHGG xenografts (PDX) will be used to define the cell types present and identify 
differentially regulated oncogenic pathways that drive their growth. Pathway expression will be knocked down 
by targeting key effector genes with shRNA using stable lentiviral transduction. The effect on tumor growth will 
be evaluated using survival, histology and single-cell RNA-Seq. 
Aim 2 will perform lineage tracing to determine whether a single PIC cell type produces all of the 
proliferating cell types that comprise PHGG. Lineage tracing will be performed in a mouse PDX model. Singlecell genomic DNA sequencing will be performed on PDX tumors. Mutational signatures consisting of single and 
multiple nucleotide variations as well as copy number variation will be used to define each cell type. Conserved 
patterns of mutation among cell types will be used to determine the hierarchical relationships among cell types. 
Once the lineage relationships are worked out, resistance to RT will be studied in the PDX model. RT is the 
most consistently effective therapy against PHGG but works only temporarily before cells regrow. RT 
resistance by cell type will be determined based upon differential survival of cell types versus control following 
RT. Drug screening of resistant cell types to identify radiation sensitizers will be performed. The candidate 
drugs will be combined with RT to investigate their effectiveness at increasing the duration of the RT effect.

Terms: <Astrocytes><Astrocytus><Astroglia><Biologic Characteristic><Biological><Biological Characteristics><Cancers><Cell Body><Cell Growth and Maintenance><Cell Growth in Number><Cell Maintenance><Cell Multiplication><Cell Proliferation><Cell Survival><Cell Viability><Cells><Cellular Expansion><Cellular Growth><Cellular Proliferation><Characteristics><Childhood><Childhood Brain Neoplasm><Childhood Brain Tumor><Childhood CNS Neoplasm><Childhood CNS Tumor><Childhood Central Nervous System Neoplasm><Childhood Central Nervous System Tumor><Childhood Glioma><Clinical Trials><Complementary DNA><Control Groups><Copy Number Polymorphism><DNA seq><DNA sequencing><DNAseq><Data><Development><Disease><Disorder><Drug Screening><Drugs><Effectiveness><Foundations><Generalized Growth><Genes><Genetic Alteration><Genetic Change><Genetic defect><Goals><Growth><Heterogeneity><Heterograft><Heterologous Transplantation><Histology><Histones><Individual><Institution><Intratumoral heterogeneity><Investigation><Knowledge><L-Lysine><Lysine><Malignant Neoplasms><Malignant Tumor><Mediating><Medication><Methionine><Methods><Mice><Mice Mammals><Molecular><Murine><Mus><Mutation><Neoplastic Colony-Forming Units><Neoplastic Stem Cells><Normal Cell><Nucleotides><Oncogenesis><Oncogenic><Operative Procedures><Operative Surgical Procedures><PDX model><Pathway interactions><Patient derived xenograft><Patients><Pattern><Pediatric Glioma><Pediatric high-grade glioma><Pharmaceutical Preparations><Phenotype><Play><Population><Population Decreases><Postdoc><Postdoctoral Fellow><Predisposition><Progenitor Cells><Proliferating><Radiation Sensitizers><Radiation therapy><Radiation-Sensitizing Agents><Radiation-Sensitizing Drugs><Radiosensitizing Agents><Radiosensitizing Drugs><Radiotherapeutics><Radiotherapy><Radiotherapy sensitizer><Recurrence><Recurrent><Research><Research Associate><Resistance><Role><Sampling><Somatic Mutation><Surgical><Surgical Interventions><Surgical Procedure><Survival Rate><Susceptibility><Testing><Therapeutic><Therapeutic Effect><Tissue Growth><Tumor Bank><Tumor Biology><Tumor Cell><Tumor Stem Cells><Variant><Variation><Work><Xenograft><Xenograft Model><Xenograft procedure><Xenotransplantation><astrocytic glia><biologic><cDNA><cancer death in children><cancer mortality in children><cancer related death in children><cell growth><cell type><chemotherapy><childhood cancer death><childhood cancer mortality><copy number variant><copy number variation><developmental><diffuse midline glioma><drug candidate><drug/agent><effective therapy><effective treatment><genome mutation><heterogeneity in tumors><in vivo><intervention design><intra-tumoral heterogeneity><intratumor heterogeneity><knock-down><knockdown><lentiviral-transduced><lentivirally transduced><lentivirus transduced><malignancy><mouse model><murine model><neoplasm/cancer><neoplastic cell><neural><oligodendrocyte precursor><oligodendrocyte progenitor><oligodendrocyte stem cell><ontogeny><pathway><patient derived xenograft model><pediatric><pediatric CNS neoplasm><pediatric CNS tumor><pediatric brain neoplasm><pediatric brain tumor><pediatric central nervous system neoplasm><pediatric central nervous system tumor><pharmacologic><post-doc><post-doctoral><post-doctoral trainee><pre-doc><pre-doctoral><predoctoral><progenitor><progenitor cell differentiation><progenitor cell population><progenitor differentiation><progenitor population><radiation effect><radiation treatment><radiosensitizer><research associates><resistance mechanism><resistance to therapy><resistant><resistant mechanism><resistant to therapy><scRNA-seq><self-renew><self-renewal><shRNA><short hairpin RNA><single cell RNA-seq><single cell RNAseq><single cell analysis><single cell expression profiling><single cell genomics><single cell transcriptomic profiling><single-cell RNA sequencing><small hairpin RNA><social role><somatic variant><stem><stem and progenitor cell population><stem and progenitor differentiation><stem cell differentiation><stem cell population><stem cells><surgery><therapeutic resistance><therapy design><therapy resistant><tool><treatment design><treatment resistance><treatment with radiation><tumor><tumor growth><tumor heterogeneity><tumor initiation><tumor progenitor><tumor xenograft><tumorigenesis><xeno-transplant><xeno-transplantation><xenograft transplant model><xenotransplant model>