Project description:DNA methyltransferase 3A (DNMT3A) gene is mutated in various myeloid neoplasms including acute myeloid leukemia (AML), especially at the Arg882 and associated with inferior outcomes. Despite the current progress of functional role of DNMT3A mutations, the molecular pathogenesis of myeloid malignancies remains poorly understood. The mechanisms of AML transformation and functional role of DNMT3A mutations through its target genes in the leukemogenesis remain to be explored. Here we wished to perform the differential genomic-methylation profile in U937 cells over-expressed with DNMT3A-Arg882His/Cys (R882H/C) mutations including DNMT3A-WT and vector using Illumina MethylationEPIC BeadChip microarray. Results: Differential genomic-methylation assess identified both hypo- and hypermethylation features in different regions throughout the whole genome of DNMT3A mutants-transduced U937 cells.
Project description:DNA methyltransferase 3A (DNMT3A) gene is mutated in various myeloid neoplasms including acute myeloid leukemia (AML), especially at the Arg882 and associated with inferior outcomes. Despite the current progress of functional role of DNMT3A mutations, the molecular pathogenesis of myeloid malignancies remains poorly understood. The mechanisms of AML transformation and functional role of DNMT3A mutations through its target genes in the leukemogenesis remain to be explored. Here we wished to perform the differential gene expression profile in U937 cells over-expressed with DNMT3A-Arg882His/Cys (R882H/C) mutations including DNMT3A-WT and vector. Results: Gene expression profiling analysis revealed aberrant expression of several cell-cycle and apoptosis-related genes in U937 cells transduced with mutant DNMT3A compared to WT- or vector control.
Project description:DNA methyltransferase 3A (DNMT3A) gene is mutated in various myeloid neoplasms including acute myeloid leukemia (AML), especially at the Arg882 and associated with inferior outcomes. Here we wished to perform the differential genomic-methylation profile in EOL-1 cells over-expressed with DNMT3A-Arg882Cys(R882C) and DNMT3A-Ser714Cys (S714C) mutations including DNMT3A-WT and vector. Results: Differential genomic-methylation assess identified both hypo- and hypermethylation features in different regions throughout the whole genome of DNMT3A mutants-transduced EOL-1 cells.
Project description:TP53 is the most commonly mutated gene in cancer, and gain-of-function mutations have wide-ranging effects. Efforts to reactivate wild-type p53 function and inhibit mutant functions have been complicated by the variety of TP53 mutations. Identified from a screen, the NSC59984 compound has been shown to restore activity to mutant p53 in colorectal cancer cells. Here, we investigated its effects on esophageal adenocarcinoma cells with specific p53 hot-spot mutations. NSC59984 treatment of cells reactivated p53 transcriptional regulation, inducing mitochondrial intrinsic apoptosis. Analysis of its effects on cellular metabolism demonstrated increased utilization of the pentose phosphate pathway and inhibition of glycolysis at the fructose-1,6-bisphosphate to fructose 6-phosphate junction. Furthermore, treatment of cells with NSC59984 increased reactive oxygen species production and decreased glutathione levels; these effects were enhanced by the addition of buthionine sulfoximine and inhibited by N-acetyl cysteine. We found that the effects of NSC59984 were substantially greater in cells harboring the p53 R248W mutation. Overall, these findings demonstrate p53-dependent effects of NSC59984 on cellular metabolism, with increased activity in cells harboring the p53 R248W mutation. This research highlights the importance of defining the mutational status of a particular cancer to create a patient-centric strategy for the treatment of p53-driven cancers.
Project description:Dnmt3a is the most recurrently mutated gene in clonal hematopoiesis (CH), and it is a critical regulator of hematopoietic stem cells (HSCs). Conditional deletion of Dnmt3a in mouse HSC results in enhanced self-renewal but impaired differentiation. Dnmt3a encodes for a de novo DNA methyltransferase enzyme but both mouse and human cells with loss of Dnmt3a show minimal change in DNA methylation levels which do not correlate with gene expression differences. To understand if there are methylation differences between control and mutant (R878H) Dnmt3a, we are performing WGBS.
Project description:Despite the impact of DNMT3A mutation in acute myeloid leukemia has been emphasized, the precise molecular mechanisms in leukemogenesis are largely unknown. Here we show that, in murine transplantation experiments, recipients transplanted with DNMT3A mutant-transduced cells exhibit aberrant hematopoietic stem cell (HSC) accumulation. Differentiation-associated genes are down-regulated without accompanying changes in methylation status of their promoter-associated CpG islands in DNMT3A mutant-transduced stem/progenitor cells. DNMT3A mutant also promotes monoblastic transformation in vitro in combination with HOXA9. Molecularly, DNMT3A mutant interacts with polycomb repressive complex 1 (PRC1), leading to transcriptional silencing of PU.1. Suppression of PRC1 impairs aberrant HSC accumulation and monoblastic transformation. Taken together, our results highlight the functional role of DNMT3A mutation, forming the basis for leukemia development.