Project description:MiR-142 is dynamically expressed and plays a regulatory role in hematopoiesis. Based on the simple observation that miR-142 levels are significantly lower in CD34+CD38- cells from blast crisis (BC) chronic myeloid leukemia (CML). CML patients compared with chronic phase (CP) CML patients (p=0.002), we hypothesized that miR-142 deficit plays a role in BC transformation. To test this hypothesis, we generated a miR-142 KO BCR-ABL (i.e., miR-142−/−BCR-ABL) mouse by crossing a miR-142−/− mouse with a miR-142+/+BCR-ABL mouse. While the miR-142+/+BCR-ABL mice developed and died of CP CML, the miR-142−/−BCR-ABL mice developed a BC-like phenotype in the absence of any other acquired gene mutations and died significantly sooner than miR-142+/+BCR-ABL CP controls (p=0.001). Leukemic stem cell (LSC)-enriched Lineage-Sca-1+c-Kit+ cells (LSKs) from diseased miR-142−/−BCR-ABL mice transplanted into congenic recipients, recapitulated the BC features thereby suggesting stable transformation of CP-LSCs into BC-LSCs in the miR-142 KO CML mouse. Single cell (sc) RNA-seq profiling showed that miR-142 deficit changed the cellular landscape of the miR-142−/−BCR-ABL LSKs compared with miR-142+/+BCR-ABL LSKs with expansion of myeloid-primed and loss of lymphoid-primed factions. Bulk RNA-seq analyses along with unbiased metabolomic profiling and functional metabolic assays demonstrated enhanced fatty acid β-oxidation (FAO) and oxidative phosphorylation (OxPhos) in miR-142−/−BCR-ABL LSKs vs miR-142+/+BCR-ABL LSKs. MiR-142 deficit enhanced FAO in miR-142−/−BCR-ABL LSKs by increasing the expression of CPT1A and CPT1B, that controls the cytosol-to-mitochondrial acyl-carnitine transport, a critical step in FAO. MiR-142 deficit also enhanced OxPhos in miR-142−/−BCR-ABL LSKs by increasing mitochondrial fusion and activity. As the homeostasis and activity of LSCs depend on higher levels of these oxidative metabolism processes, we then postulate that miR-142 deficit is a potentially druggable target for BC-LSCs. To this end, we developed a novel CpG-miR-142 mimic oligonucleotide (ODN; i.e., CpG-M-miR-142) that corrected the miR-142 deficit and alone or in combination with a tyrosine kinase inhibitor (TKI) significantly reduced LSC burden and prolonged survival of miR-142−/−BCR-ABL mice. The results from murine models were validated in BC CD34+CD38- primary blasts and patient-derived xenografts (PDXs). In conclusion, an acquired miR-142 deficit sufficed in transforming CP-LSCs into BC-LSCs, via enhancement of bioenergetic oxidative metabolism in absence of any additional gene mutations, and likely represent a novel therapeutic target in BC CML.
Project description:To gain insight into how miR-142 deficit drives a BC-like transformation, we performed RNA-seq on bone marrow (BM) Lin-Sca-1+c-Kit+ cells (LSKs) harvested from normal miR-142+/+ (wt) and miR-142−/− (miR-142 KO) mice, as well as from leukemic miR-142+/+ BCR-ABL (CP CML) and miR-142−/− BCR-ABL (BC CML) mice, two weeks after BCR-ABL induction. We then performed gene expression profiling analysis using data obtained from RNA-seq of 24 samples of LSK cells from 4 mouse strains (KO vs WT, KO CML vs CML).
Project description:Transcriptional profiling of postpartum day 0 mouse brain, comparing TDAG51 wild-type (WT) vs TDAG51 knockout (KO), and TDAG51 KO transgenic (Tg) vs TDAG51 KO.
Project description:Mutations in the E3 ubiquitin ligase Mkrn3 are associated with precocious puberty in humans. In order to determine the targets of Mkrn3, we performed a TMT-based proteomic analysis of Mkrn3 WT vs KO mouse brains.
Project description:We examined, compared, and analyzed the transcriptome profile (RNA-seq) of WT vs Reck vascular KO (Reck flex2/Δex1; Tie2Cre) P0 mouse brains. Specifically, cortical transcriptomic differences (between WT and mutant genotypes) were compared separately from subcortical transcriptomic changes.
