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Biology subjects

De Mas, V.

Publications and source records attributed to De Mas, V..

2 recordsLinked to original sources

FAO-supported OxPhos leukemic stem cells are sensitive to cold.

Targeting mitochondrial oxidative phosphorylation (OxPhos) metabolism has revealed a potential weakness for leukemic stem cells (LSCs) that can be exploited for therapeutic purposes. Fatty acids oxidation (FAO) is a crucial OxPhos-fueling catabolic pathway for some AML and for chemotherapy-resistant AML cells. Here, we identified cold sensitivity at 4{degrees}C (cold killing challenge: CKC4), as a novel vulnerability that selectively kills FAO-supported OxPhos LSCs in Acute Myeloid Leukemia while sparing normal hematopoietic stem cells (HSCs). Cell death of OxPhos leukemic cells was induced by membrane permeabilization at 4{degrees}C while by sharp contrast, leukemic cells relying on glycolysis were resistant. Forcing glycolytic cells into OxPhos metabolism sensitized them to CKC4. We show using lipidomic and proteomic analyzes that OxPhos shapes the composition of the plasma membrane and introduce variation of 22 lipid subfamilies between cold-sensitive and cold-resistant cells. Cold sensitivity is a potential OxPhos biomarker. SignificanceThis study reveals that mitochondrial energetics fueled by FAO metabolism introduces membrane fragility upon cold exposure in OxPhos-driven AMLs and in LSCs. This novel physical property of Leukemic cells and LSCs opens new avenues for biomarker and diagnostics as well as for anti-OxPhos drug screening and LSCs targeting. One Sentence SummaryOxPhos leukemic cells die at 4{degrees}C

cancer biology↗

STAT5-dependent regulation of CDC25A by miR-16 controls proliferation and differentiation in FLT3-ITD acute myeloid leukemia

We recently identified the CDC25A phosphatase as a key actor in proliferation and differentiation in acute myeloid leukemia which expresses the FLT3-ITD mutation. In this paper we demonstrate that CDC25A level is controlled by a complex STAT5/miR-16 transcription and translation pathway working downstream of this receptor. First, we established by CHIP analysis that STAT5 is directly involved in FLT3-ITD-dependent CDC25A gene transcription. In addition, we determined that miR-16 expression is repressed by FLT3-ITD activity, and that STAT5 participates in this repression. In accordance with these results, miR-16 expression was significantly reduced in a panel of AML primary samples carrying the FLT3-ITD mutation when compared with FLT3wt cells. The expression of a miR-16 mimic reduced CDC25A protein and mRNA levels, and RNA interference-mediated down modulation of miR-16 restored CDC25A expression in response to FLT3-ITD inhibition. Finally, decreasing miR-16 expression partially restored the proliferation of cells treated with the FLT3 inhibitor AC220, while the expression of miR-16 mimic stopped this proliferation and induced monocytic differentiation of AML cells. In summary, we identified a FLT3-ITD/STAT5/miR-16/CDC25A axis essential for AML cell proliferation and differentiation.

cancer biology↗