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bioRxiv · 10.1101/2023.09.11.557112

Insight into spatial intratumoral genomic evolution in glioblastoma

Abstract

Glioblastoma undergoes a complex and dynamic evolution involving genetic and epigenetic changes. Understanding the mechanisms underlying this evolution is vital for the development of efficient therapeutic strategies. Although treatment resistance is associated with intratumoral heterogeneity in glioblastoma, it remains uncertain whether hypometabolic and hypermetabolic lesions observed through positron emission tomography (PET) imaging are influenced by spatial intratumoral genomic evolution. In this study, we precisely isolated autologous hypometabolic and hypermetabolic lesions from glioblastoma using advanced neurosurgical and brain tumor imaging technologies, followed by comprehensive whole-genome exome and transcriptome analyses. Our findings revealed that hypermetabolic lesions evolved from hypometabolic lesions, harbored shrewd focal amplifications and deletions, and exhibited a higher frequency of critical genomic alterations linked to increased aggressiveness, upregulated APOBEC3 and hypoxic genes, and downregulated putative tumor suppressors. This study highlights spatial genomic evolution with diagnostic implications and unveils the obstacles and possibilities that should be considered in the development of novel therapeutic strategies. Statement of significanceGlioblastoma is a multifaceted disease that is difficult to treat, and insights into the metabolic gradient observed in imaging and the underlying role of genomic evolution are lacking. This study is the first to investigate the molecular basis of hypermetabolic tumor lesions in glioblastoma using precise three-dimensional biopsy isolation, whole genome/exome, and mRNA sequencing. These findings have diagnostic significance, provide insights into therapeutic resistance, and shed light on the obstacles encountered by precision therapeutics for glioblastoma.

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BibTeXRIS

Anand, A., Petersen, J. K., Andersen, L. v. B., Burton, M., Larsen, M. J., Pedersen, C. B., Poulsen, F. R., Grupe, P., Kruse, T. A., Thomassen, M., Kristensen, B. W.. 2023-09-12. Insight into spatial intratumoral genomic evolution in glioblastoma. https://doi.org/10.1101/2023.09.11.557112

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