Clinical outcomes in patients with WHO grade II/III astrocytoma, oligodendroglioma or secondary glioblastoma remain poor. Isocitrate dehydrogenase 1 (IDH1) is mutated in > 70% of these tumors, making it an attractive therapeutic target. To determine the efficacy of our newly developed mutant IDH1 inhibitor, SYC-435 (1-hydroxypyridin-2-one), we treated orthotopic glioma xenograft model (IC-BT142AOA) carrying R132H mutation and our newly established orthotopic patient-derived xenograft (PDX) model of recurrent anaplastic oligoastrocytoma (IC-V0914AOA) bearing R132C mutation.
View Article and Find Full Text PDFAnn Clin Transl Neurol
October 2021
Exome sequencing (ES) has revolutionized rare disease management, yet only ~25%-30% of patients receive a molecular diagnosis. A limiting factor is the quality of available phenotypic data. Here, we describe how deep clinicopathological phenotyping yielded a molecular diagnosis for a 19-year-old proband with muscular dystrophy and negative clinical ES.
View Article and Find Full Text PDFAtypical teratoid/rhabdoid tumor (ATRT) is a high-grade central nervous system tumor, with poor prognosis despite intensive multimodal therapy. Loss of nuclear immunostaining for INI1 due to inactivation of the hSNF5/INI1 tumor suppressor gene is pathognomonic of ATRT. We present a patient with congenital ATRT, who had spontaneous tumor regression without therapy, and is disease-free 4 years later.
View Article and Find Full Text PDFTo identify cellular and molecular changes that driver pediatric low grade glioma (PLGG) progression, we analyzed putative cancer stem cells (CSCs) and evaluated key biological changes in a novel and progressive patient-derived orthotopic xenograft (PDOX) mouse model. Flow cytometric analysis of 22 PLGGs detected CD133 (<1.5%) and CD15 (20.
View Article and Find Full Text PDFFOXG1 is a transcription factor that interacts with multiple signaling pathways and modulates neuronal differentiation in the telencephalon. Dysregulation of FOXG1 expression has been previously reported in medulloblastoma. In this study, we demonstrate a regional specific expression of FOXG1 and its colocalization with Nestin expression in the premigratory mitotically active (outer) layer of the external granular layer of the cerebellum.
View Article and Find Full Text PDFBackground: Adult pilocytic astrocytomas (PAs) are rare and have an aggressive clinical course compared with pediatric patients. Constitutive Ras/RAF/MAPK signaling appears to be an important oncogenic event in sporadic PA. We evaluated clinical data and molecular profiles of adult PAs at our institution.
View Article and Find Full Text PDFAn atypical teratoid/rhabdoid tumor (AT/RT) is a highly malignant embryonal tumor most often occurring in the posterior fossa in children younger than 3 years of age. Adult cases of AT/RT are very rare, and 27 cases with a diagnosis of either AT/RT or (malignant) rhabdoid tumor have been reported to date. The authors report an adult case of an AT/RT occurring in the pineal region with molecular cytogenetic and immunohistochemical confirmation.
View Article and Find Full Text PDFObject: Medulloblastoma (MB) is a malignant embryonal tumor of the cerebellum. Amplification of c-myc or N-myc is infrequently identified and, when present, is often associated with the large cell/anaplastic (LC/A) phenotype. The frequency of low-level copy gain of myc oncogenes and its relationship to prognosis of MB has not been explored.
View Article and Find Full Text PDFThe growth pattern of pilocytic astrocytoma (PAs) is unpredictable. Gene expression profiling has recently demonstrated an inverse relationship between myelin basic protein (MBP) expression and progression free survival (PFS) in PAs. We present here the pattern of expression of oligodendroglial differentiation markers (ODMs) in PAs by immunohistochemistry and their correlation with PI and PFS.
View Article and Find Full Text PDFMedulloblastomas represent 20% of malignant brain tumors of childhood. Although, they show multiple, non-random genomic alterations, no common, early genetic event involving all histologic types of medulloblastomas have been described. Nineteen medulloblastomas were analyzed using chromosomal comparative genomic hybridization (cCGH).
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