Resistance to chemotherapy remains a major hurdle to the cure of Acute Myeloid Leukemia (AML) patients. Recent studies indicate a minority of malignant cells, termed drug-tolerant persisters (DTPs), stochastically upregulate stress pathways to evade cell death upon acute exposure to chemotherapy without acquiring new genetic mutations. This chemoresistant state is transient and the cells return to baseline after removal of chemotherapy.
View Article and Find Full Text PDFPatients with brain metastases (BM) face a 90% mortality rate within one year of diagnosis and the current standard of care is palliative. Targeting BM-initiating cells (BMICs) is a feasible strategy to treat BM, but druggable targets are limited. Here, we apply Connectivity Map analysis to lung-, breast-, and melanoma-pre-metastatic BMIC gene expression signatures and identify inosine monophosphate dehydrogenase (IMPDH), the rate-limiting enzyme in the de novo GTP synthesis pathway, as a target for BM.
View Article and Find Full Text PDFLiquid chromatography-mass spectrometry (LC-MS)-based metabolomics and lipidomics have recently been used to show that MYC-amplified group 3 medulloblastoma tumors are driven by metabolic reprogramming. Here, we present a protocol to extract metabolites and lipids from human medulloblastoma brain tumor-initiating cells and normal neural stem cells. We describe untargeted LC-MS methods that can be used to achieve extensive coverage of the polar metabolome and lipidome.
View Article and Find Full Text PDFCommonly, in MS-based untargeted metabolomics, some metabolites cannot be confidently identified due to ambiguities in resolving isobars and structurally similar species. To address this, analytical techniques beyond traditional MS analysis, such as MS fragmentation, can be applied to probe metabolites for additional structural information. In MS fragmentation, recursive cycles of activation are applied to fragment ions originating from the same precursor ion detected on an MS spectrum.
View Article and Find Full Text PDFMYC-driven medulloblastoma (MB) is an aggressive pediatric brain tumor characterized by therapy resistance and disease recurrence. Here, we integrated data from unbiased genetic screening and metabolomic profiling to identify multiple cancer-selective metabolic vulnerabilities in MYC-driven MB tumor cells, which are amenable to therapeutic targeting. Among these targets, dihydroorotate dehydrogenase (DHODH), an enzyme that catalyzes de novo pyrimidine biosynthesis, emerged as a favorable candidate for therapeutic targeting.
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