Project description:We have developed a new conditional transgenic mouse showing that MLL-ENL, at an endogenous-like expression level, induces leukemic transformation selectively in LT-HSCs. To investigate the molecular mechanism of leukemic transformation in LT-HSCs conditionally expressing MLL-ENL, we preliminarily performed comprehensive gene expression profiling of CreER-transduced LT-HSCs and ST-HSCs using cDNA microarray analysis.
Project description:We have developed a new conditional transgenic mouse showing that MLL-ENL, at an endogenous-like expression level, induces leukemic transformation selectively in LT-HSCs. To investigate the molecular mechanism of leukemic transformation in LT-HSCs conditionally expressing MLL-ENL, we preliminarily performed comprehensive gene expression profiling of CreER-transduced LT-HSCs and ST-HSCs using cDNA microarray analysis. For initial screening of candidate genes invloved in the leukemic transformation, total RNA was extracted from colony-forming cells derived from LT-HSCs and ST-HSCs transduced with CreER or mock. Four samples were analyzed, and CreER-transduced LT/ST-HSC-derived cells were compared with mock-transduced LT/ST-HSC-derived cells, while CreER/mock-transduced LT-HSC-derived cells were compared with CreER/mock-transduced ST-HSC-derived cells.
Project description:To investigate the molecular mechanism of leukemic transformation by MLL-ENL in HSCs and immature progenitors, we preliminarily performed comprehensive gene expression profiling of ST-HSCs and MPP2 cells by RNA-seq using a mouse model enabling to conditionally express MLL-ENL at an endogenous-like expression level.
Project description:Expression data from conditionally immortalized MLL-AF9 and MLL-ENL hematopoietic progenitor cells following loss of MLL-fusion oncogene
Project description:RNA-Seq of 1) human AML samples; 2) sorted, uncultured distinct population from human cord blood (CB); 3) short-term (ST) cultured sorted CB cells transduced with MLL-ENL, MLL-AF6 or untransduced; and 4) cultured (LT) sorted CB cells transformed with MLL-ENL or MLL-AF6. Cells from MLL-fusion AML patients are bulk. Several cords were used for the sorting (CB1, CB2, CB3, 135, 141...) and these represent biological replicates. Several samples were sequenced several times in different lanes and results were merged together for the analysis (rep1,rep2...). Samples were used to determine the different effect of MLL-fusions in different celltypes just after the transduction, and after a longer time period when cells were transformed. Sorted CB samples, uncultured as well as transformed by MLL-fusions, were used in machine learning approach to predict which of the patients originated from which cell-type of origin.
Project description:Purpose: The goal of this study is to compare NGS-derived transcriptome profiling (RNA-seq) of Ltbr-deficient and -proficient LT/ST-HSCs isolated from chimeric mice. Methods: Transcriptomic profiles of Ltbr-/- and Ly5.1 LT/ST-HSCs isolated from chimeric mice 6 weeks after reconstitution were assessed in triplicate by deep sequencing, using Illumina NextSeq 500. qRT–PCR validation was performed using TaqMan and SYBR Green assays. Results: We mapped about 60 million sequence reads per sample to the mouse genome (GRCm38 - mm10) and identified expressed transcripts in Ltbr-/- and Ly5.1 LT/ST-HSCs isolated from chimeric mice. RNA-seq. data confirmed stable expression of known housekeeping genes. Differentially expressed genes between the Ltbr-/- and Ly5.1 LT/ST-HSCs were identified with a fold change ≥1.5 and FDR p-value <0.05. Conclusions: Our study represents the first detailed transcriptome analysis of Ltbr-deficient and -proficient LT/ST-HSCs, with biologic replicates, generated by RNA-seq. technology. Our results show that Ltbr signaling regulates HSC proliferation and differentiation. Evaluation of mRNA content in Ltbr-/- LT/ST-HSCs revealed that Ltbr-deficiency enhances HSC proliferation, differentiation, cell cycle and reduces the activity of canonical NFkB signaling.
Project description:Genome wide RNA-seq from pGM and HSCs in response to expression of the MLL-ENL fusion gene Examination of mRNA abundance in two cell types with or without induction of the MLL-ENL fusion gene (following 48h of culture)
Project description:Chromosomal translocations encoding the MLL-AF9 and MLL-ENL fusion transcription factors are prevalent in infant acute leukaemia and therapy-related leukaemia. In order to conditionally express the MLL-fusion oncogene in primary haematopoietic progenitor cells (HPC), retroviral delivery of the Tet-off expression system was used (Horton et al., Cancer Res, 2005). Treatment of the conditional cells with Doxycycline caused a decrease in MLL-AF9/ENL mRNA and protein expression, and resulted in terminal differentiation of the cells. By analysing global changes in gene expression after treatment of cells with Doxycycline we were able to identify a number of potential transcriptional target genes of the MLL-AF9 and MLL-ENL fusion oncogenes.
