Project description:To better understand proteostasis in health and disease, determination of protein half-lives is essential. We improved the precision and accuracy of peptide-ion intensity based quantification in order to enable accurate determination of protein turnover in non-dividing cells using dynamic-SILAC. This enabled precise and accurate protein half-life determination ranging from 10 to more than 1000 hours. We achieve good proteomic coverage ranging from four to six thousand proteins in several types of non-dividing cells, corresponding to a total of 9699 unique proteins over the entire dataset. Good agreement was observed in half-lives between B-cells, natural killer cells and monocytes, while hepatocytes and mouse embryonic neurons showed substantial differences. Our comprehensive dataset enabled extension and statistical validation of the previous observation that subunits of protein complexes tend to have coherent turnover. Furthermore, we observed complex architecture dependent turnover within complexes of the proteasome and the nuclear pore complex. Our method is broadly applicable and might be used to investigate protein turnover in various cell types.
Project description:FMS-like tyrosine kinase 3 (FLT3) mutations in acute myeloid leukemia (AML) are associated with adverseprognosis. FLT3 inhibitors (FLT3i) improve therapeutic response, however diverse resistance mechanisms such as adaptations in lipid metabolism have been identified. We hypothesized that a lipid-rich ketogenic diet (KD) might alter both host and tumoral lipid metabolism, enhancing responses to FLT3i. In FLT3-mutated AML mouse models, three weeks of lard- or plant-based KD improved efficacy of FLT3i by two-fold reduction of engraftment and tumor burden. KD increased ketone bodies and lipid accumulation inplasma, liver and AML cells, and also induced a PUFA:MUFA imbalance. KD impacted pentoses, hexoses and amino acid metabolism, enhancing sugar phosphates and vitamins in host. Mechanistically, KD rewired anabolism towards fatty acid oxidation and glycine-utilizing pathways, modulated the expression of FLT3 signaling pathways and lipid biosynthesis, and promoted tumor cell differentiation. In conclusion, this study shows that KD reduces FLT3i-resistance, offering a promising therapeutic solution.
Project description:FMS-like tyrosine kinase 3 (FLT3) mutations in acute myeloid leukemia (AML) are associated with adverseprognosis. FLT3 inhibitors (FLT3i) improve therapeutic response, however diverse resistance mechanisms such as adaptations in lipid metabolism have been identified. We hypothesized that a lipid-rich ketogenic diet (KD) might alter both host and tumoral lipid metabolism, enhancing responses to FLT3i. In FLT3-mutated AML mouse models, three weeks of lard- or plant-based KD improved efficacy of FLT3i by two-fold reduction of engraftment and tumor burden. KD increased ketone bodies and lipid accumulation inplasma, liver and AML cells, and also induced a PUFA:MUFA imbalance. KD impacted pentoses, hexoses and amino acid metabolism, enhancing sugar phosphates and vitamins in host. Mechanistically, KD rewired anabolism towards fatty acid oxidation and glycine-utilizing pathways, modulated the expression of FLT3 signaling pathways and lipid biosynthesis, and promoted tumor cell differentiation. In conclusion, this study shows that KD reduces FLT3i-resistance, offering a promising therapeutic solution.