RESUMEN
Tumor adaptation or selection is thought to underlie therapy resistance in glioma. To investigate longitudinal epigenetic evolution of gliomas in response to therapeutic pressure, we performed an epigenomic analysis of 132 matched initial and recurrent tumors from patients with IDH-wildtype (IDHwt) and IDH-mutant (IDHmut) glioma. IDHwt gliomas showed a stable epigenome over time with relatively low levels of global methylation. The epigenome of IDHmut gliomas showed initial high levels of genome-wide DNA methylation that was progressively reduced to levels similar to those of IDHwt tumors. Integration of epigenomics, gene expression, and functional genomics identified HOXD13 as a master regulator of IDHmut astrocytoma evolution. Furthermore, relapse of IDHmut tumors was accompanied by histologic progression that was associated with survival, as validated in an independent cohort. Finally, the initial cell composition of the tumor microenvironment varied between IDHwt and IDHmut tumors and changed differentially following treatment, suggesting increased neoangiogenesis and T-cell infiltration upon treatment of IDHmut gliomas. This study provides one of the largest cohorts of paired longitudinal glioma samples with epigenomic, transcriptomic, and genomic profiling and suggests that treatment of IDHmut glioma is associated with epigenomic evolution toward an IDHwt-like phenotype. SIGNIFICANCE: Standard treatments are related to loss of DNA methylation in IDHmut glioma, resulting in epigenetic activation of genes associated with tumor progression and alterations in the microenvironment that resemble treatment-naïve IDHwt glioma.
Asunto(s)
Neoplasias Encefálicas , Glioma , Isocitrato Deshidrogenasa , Humanos , Neoplasias Encefálicas/patología , Epigénesis Genética , Epigenómica , Glioma/patología , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Mutación , Recurrencia Local de Neoplasia/genética , Microambiente TumoralRESUMEN
A 67-year-old Dutch woman presented with neurological symptoms of several months duration. MRI scans of the brain showed intracerebral lesions. Brain biopsy revealed granulomatous inflammation and remnants of worm eggs. Eggs of Schistosoma mansoni were found in the stools and serological tests were positive for Schistosoma. From additional history taking it became clear that the patient contracted schistosomiasis when visiting Brazil several years before. She was treated with praziquantel and corticosteroids. Neuroschistosomiasis is a rare but severe complication of Schistosoma infection. This diagnosis should be considered in patients that travelled to or originate from endemic schistosomiasis areas.