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Agathocleous, M.

Publications and source records attributed to Agathocleous, M..

2 recordsLinked to original sources

Cell-type specific requirement for pyruvate dehydrogenase in hematopoiesis and leukemia development.

Cancer cells have different metabolic requirements as compared to their corresponding normal tissues. This is thought to reflect metabolic reprogramming during transformation. An alternative possibility is that some metabolic requirements of cancer cells reflect a maintenance of the metabolism of the specific normal cell type from which cancer cells originate. Here, we investigate this hypothesis by comparing glucose use in normal hematopoiesis and in leukemia. T cell progenitors in the thymus were glucose avid and oxidized more glucose in the tricarboxylic acid (TCA) cycle through pyruvate dehydrogenase (PDH) as compared to hematopoietic stem cells (HSCs) or other hematopoietic cells. PDH deletion reduced the number of double positive (DP) T cell progenitors but had no effect on HSCs, myeloid progenitors and other hematopoietic cells we examined. PDH deletion blocked the development of T cell leukemia from Pten-deficient DP progenitors, but not the development of a myeloid neoplasm from Pten-deficient HSCs or myeloid progenitors. Therefore, the requirement of glucose oxidation for leukemia development is inherited from the normal cell of origin and occurs independently of the driver genetic lesion. PDH was not required in vivo to generate acetyl-CoA or maintain levels of TCA cycle metabolites but to prevent pyruvate accumulation and to maintain glutathione levels and redox homeostasis.

cancer biology↗

Metabolomic profiling of rare cell populations isolated by flow cytometry from tissues

Little is known about the metabolic regulation of rare cell populations because most metabolites are hard to detect in small numbers of cells. We previously described a method for metabolomic profiling of flow cytometrically-isolated hematopoietic stem cells (HSCs) that detects approximately 60 metabolites in 10,000 cells (Agathocleous et al., 2017). Here we describe a new method involving hydrophilic liquid interaction chromatography (HILIC) and high-sensitivity orbitrap mass spectrometry that detected approximately 160 metabolites in 10,000 HSCs, including many more glycolytic and lipid intermediates. We improved chromatographic separation, increased mass resolution, minimized ion suppression, extracted with acetonitrile, and eliminated sample drying. Most metabolites did not significantly change during cell preparation and sorting. We used this method to profile HSCs and circulating melanoma cells. HSCs exhibited increased glycerophospholipid metabolites relative to unfractionated bone marrow cells and altered purine biosynthesis after methotrexate treatment in vivo. Circulating melanoma cells were depleted for purine intermediates relative to subcutaneous tumors, suggesting they decrease purine synthesis during metastasis. These methods facilitate the routine metabolomic analysis of rare cell populations from tissues. Impact statementWe developed a method for metabolomic analysis of small numbers of flow cytometrically isolated cells from rare cell populations such as hematopoietic stem cells and circulating cancer cells.

cell biology↗