Project description:We report the DNA methylation and transcriptional molecular features of paired diagnosis and relapsed Acute Myeloid Leukemia samples
Project description:We report the DNA methylation and transcriptional molecular features of paired diagnosis and relapsed Acute Myeloid Leukemia samples
Project description:Hematopoietic stem cells (HSCs) engage in complex bidirectional signals with the hematopoietic microenvironment (HM), and there is emerging evidence that leukemia stem cells (LSCs) may use similar interactions. Using a syngeneic retroviral model of MLL-AF9 induced acute myeloid leukemia (AML), we have identified 2 different stages of leukemia progression, propagated by "pre-LSCs" and established leukemia (LSCs) and compared the homing properties of these distinctive entities to that of normal HSCs. The homing and microlocalization of pre-LSCs was most similar to long-term HSCs and was dependent on cell-intrinsic Wnt signaling. In contrast, the homing of established LSCs was most similar to that of committed myeloid progenitors and distinct from HSCs. Although osteoblast-derived Dickkopf-1, a potent Wnt inhibitor known to impair HSC function, dramatically impaired normal HSC localization within the bone marrow, it did not affect pre-LSCs, LSC homing, or AML development. Mechanistically, cell-intrinsic Wnt activation was observed in human and murine AML samples, explaining the independence of MLL-AF9 LSCs from niche-derived Wnt signals. These data identify differential engagement of HM associated with leukemic progression and identify an LSC niche that is physically distinct and independent of the constraints of Wnt signaling that apply to normal HSCs.
Project description:BackgroundAcute myeloid leukemia (AML) is a myeloid neoplasm accounts for 7.6% of hematopoietic malignancies. AML is a complex disease, and understanding its pathophysiology is contributing to the improvement in the treatment and prognosis of AML. In this study, we assessed the expression profile and molecular functions of CCAAT enhancer binding protein gamma (CEBPG), a gene implicated in myeloid differentiation and AML progression.MethodsshRNA mediated gene interference was used to down-regulate the expression of CEBPG in AML cell lines, and knockdown efficiency was detected by RT-qPCR and western blotting. The effect of knockdown on the growth of AML cell lines was evaluated by CCK-8. Western blotting was used to detect PARP cleavage, and flow cytometry were used to determine the effect of knockdown on apoptosis of AML cells. Genes and pathways affected by knockdown of CEBPG were identified by gene expression analysis using RNA-seq. One of the genes affected by knockdown of CEBPG was Eukaryotic translation initiation factor 4E binding protein 1 (EIF4EBP1), a known repressor of translation. Knockdown of EIF4EBP1 was used to assess its potential role in AML progression downstream of CEBPG.ResultsWe explored the ChIP-Seq data of AML cell lines and non-AML hematopoietic cells, and found CEBPG was activated through its distal enhancer in AML cell lines. Using the public transcriptomic dataset, the Cancer Cell Line Encyclopedia (CCLE) and western blotting, we also found CEBPG was overexpressed in AML. Moreover, we observed that CEBPG promotes AML cell proliferation by activating EIF4EBP1, thus contributing to the progression of AML. These findings indicate that CEBPG could act as a potential therapeutic target for AML patients.ConclusionIn summary, we systematically explored the molecular characteristics of CEBPG in AML and identified CEBPG as a potential therapeutic target for AML patients. Our findings provide novel insights into the pathophysiology of AML and indicate a key role for CEBPG in promoting AML progression.
Project description:ObjectiveTo investigate the role of lncRNA AL645608.3 in the malignant progression of acute myeloid leukemia (AML) cells and explore relevant molecular mechanisms.MethodsThe expression level of AL645608.3 was measured in AML cell lines (THP-1, HL-60, KG-1, and AML-193) via real-time quantitative polymerase chain reaction (RT-qPCR). Small hairpin RNA (shRNA) and open reading frame of AL645608.3 were cloned into lentiviral vectors and were infected into THP-1 and AML-193 cells. The expression of casitas B-lineage lymphoma (CBL), interferon regulatory factor 6 (IRF6), and interferon beta 1 (IFNB1) was detected through RT-qPCR, and western blot. Co-immunoprecipitation (Co-IP) on IRF6 was conducted. Matrix metalloprotease-9 (MMP-9) activity was evaluated via gelatin zymography assay.ResultsLncRNA AL645608.3 was expressed in the four AML cell lines (THP-1, HL-60, KG-1, and AML-193). Silencing AL645608.3 mitigated the expression of IRF6 and IFNB1 but elevated the expression of CBL in THP-1 cells. Oppositely, AL645608.3 overexpression up-regulated the expression of IRF6 and IFNB1 but decreased the expression of CBL in AML-193 cells. Co-IP results proved that AL645608.3 could directly mediate IRF6 activity in THP-1 and AML-193 cells. MMP-9 activity was decreased by AL645608.3 knockdown and was improved by AL645608.3 overexpression in AML-193 cells.ConclusionAL645608.3 is expressed in different AML cell lines, and mediates the expression of CBL, IRF6, IFNB1, and MMP-9. These findings might deepen our comprehension of the molecular mechanisms underlying AML.
Project description:<p>Acute Myeloid Leukemia (AML) remains a clinical challenge since most patients diagnosed with AML will die from the disease. Some patients harbor treatment-refractory disease and others relapse with disease that in many cases is resistant to treatments. Our study was designed to understand the molecular basis of disease progression in AML through interrogation of patient samples collected through an international collaboration which assembled 138 paired (diagnosis and relapse) patient specimens.</p> <p>It is hoped that this resource will help researchers understand mechanisms of disease relapse in AML and contribute to the general pool of data available for analyses for this disease and general research use.</p>
Project description:Acute myeloid leukemia (AML) is an aggressive hematological malignancy with high relapse/refractory rate. Genetic and epigenetic abnormalities are driving factors for leukemogenesis. RUNX1 and RUNX2 from the Runt-related transcription factor (RUNX) family played important roles in AML pathogenesis. However, the relationship between RUNX3 and AML remains unclear. Here, we found that RUNX3 was a super-enhancer-associated gene and highly expressed in AML cells. The Cancer Genome Atlas (TCGA) database showed high expression of RUNX3 correlated with poor prognosis of AML patients. We observed that Runx3 knockdown significantly inhibited leukemia progression by inducing DNA damage to enhance apoptosis in murine AML cells. By chromatin immunoprecipitation sequencing (ChIP-seq) analysis, we discovered that RUNX3 in AML cells mainly bound more genes involved in DNA-damage repair and antiapoptosis pathways compared to that in normal bone marrow cells. Runx3 knockdown obviously inhibited the expression of these genes in AML cells. Overall, we identified RUNX3 as an oncogene overexpressed in AML cells, and Runx3 knockdown suppressed AML progression by inducing DNA damage and apoptosis.