Project description:hESC have morphologic, genetic and genomic alternatiions when cells cultured in different passaging condition. Here transcriptome of four different hESC lines were compared in two passaging methods.
Project description:hESC have morphologic, genetic and genomic alternatiions when cells cultured in different passaging condition. Here sub-karyotypic genome change in three different hESC lines were compared in two passaging methods.
Project description:In the following experiment, three different hESC cell lines (HES2, MEL1 and H9) were grown in the presence of KOSR, KOSR or mTESR containing media respectively. KOSR (Knockout serum replacement medium) is a standard media allowing the growth of hESC without the need for manual passaging - Enzymatic passaging is used instread. mTESR (Ludwig et al., 2007) is a media allowing the growth of hESC on matrigel with enzymatic passaging. At day 7 after passaging, these cells were FACs sorted for the presence of GCTM-2 and CD9 into 4 distinct fractions (p4: GCTM-2-neg, CD9-neg; p5: GCTM-2-low, CD9-low; p6: GCTM-2-medium, CD9-medium and p7: GCTM-2-high, CD9-high). For each cell line-subfraction combination, RNA was harvested and subject to microarray. From each experiment (individual cell line), 4 samples were collected (p4, p5, p6 and p7) and these were subject to microarray. In each case the experiment was performed in triplicate
Project description:In the following experiment, three different hESC cell lines (HES2, MEL1 and H9) were grown in the presence of KOSR, KOSR or mTESR containing media respectively. KOSR (Knockout serum replacement medium) is a standard media allowing the growth of hESC without the need for manual passaging - Enzymatic passaging is used instread. mTESR (Ludwig et al., 2007) is a media allowing the growth of hESC on matrigel with enzymatic passaging. At day 7 after passaging, these cells were FACs sorted for the presence of GCTM-2 and CD9 into 4 distinct fractions (p4: GCTM-2-neg, CD9-neg; p5: GCTM-2-low, CD9-low; p6: GCTM-2-medium, CD9-medium and p7: GCTM-2-high, CD9-high). For each cell line-subfraction combination, RNA was harvested and subject to microarray. From each experiment (individual cell line), 4 samples were collected (p4, p5, p6 and p7) and these were subject to microarray. In each case the experiment was performed in triplicate Three independent experiments of three consecutive passages of ESC cells were grown and subject to FACs sorting, collection and microarray. A total of 36 samples, (3 experiments of 3 replicates of 4 sorted populations of cells (p4, p5, p6, p7))
Project description:In this study, we characterize the fusion protein produced by the EPC1-PHF1 translocation in Low Grade Endometrial Stromal Sarcoma (LG-ESS) and Ossifying FibroMyxoid Tumors (OFMT). We express the fusion protein and necessary controls in K562 Cells. The fusion protein assembles a mega-complex harboring both NuA4/TIP60 and PRC2 subunits and enzymatic activities and leads to mislocalization of chromatin marks in the genome, linked to aberrant gene expression.
Project description:In this study, we characterize the fusion protein produced by the EPC1-PHF1 translocation in Low Grade Endometrial Stromal Sarcoma (LG-ESS) and Ossifying FibroMyxoid Tumors (OFMT). We express the fusion protein and necessary controls in K562 Cells. The fusion protein assembles a mega-complex harboring both NuA4/TIP60 and PRC2 subunits and enzymatic activities and leads to mislocalization of chromatin marks in the genome, linked to aberrant gene expression.
Project description:In this study, we characterize the fusion protein produced by the EPC1-PHF1 translocation in Low Grade Endometrial Stromal Sarcoma (LG-ESS) and Ossifying FibroMyxoid Tumors (OFMT). We express the fusion protein and necessary controls in K562 Cells. The fusion protein assembles a mega-complex harboring both NuA4/TIP60 and PRC2 subunits and enzymatic activities and leads to mislocalization of chromatin marks in the genome, linked to aberrant gene expression.
Project description:The self-renewal and differentiation capacities of human pluripotent stem cells (hPSCs) make them good sources of cells for cell transplantation therapy, drug development, and studies of cellular differentiation and development. However, the large numbers of cells necessary for many of these applications require extensive expansion of hPSC cultures, a process that has been associated with genetic and epigenetic alterations. We have performed a combinatorial study on both hESCs and hiPSCs to compare the effects of enzymatic vs. mechanical passaging, and feeder-free vs. mouse embryonic fibroblast feeder substrate, to on the genetic and epigenetic stability and the phenotypic characteristics of hPSCs. In extensive experiments in hEScs involving over 100 continuous passages, , we observed that both enzymatic passaging and feeder-free culture were associated with genetic instability, higher cell proliferation, and persistence of OCT4-positive cells in teratomas, with enzymatic passaging having the stronger effect. In all combinations of culture conditions except for mechanical passaging on feeder layers, we noted recurrent deletions in the genomic region containing the tumor suppressor gene TP53, which was associated with decreased mRNA expression of TP53, as well as alterations in the expression of several downstream genes consistent with a decrease in the activity of the TP53 pathway. Among the hESC cultures, we also observedculture-dependent variations in global gene expression and DNA methylation. Verification of the negative effects of enzymatic passaging and feeder-free conditions was performed in hiPSC cultures. Our results highlight the need for careful assessment of effects of culture conditions on cells intended for clinical therapies.