Project description:Analysis of reprogrammed MEFs expressing Osr2. Results provide insight into an importance of Osr2 downregulation during the reprogramming.
Project description:Analysis of NMuMG cells expressing Osr2 or treated with TGF-ß. Results provide insight into a novel function of Osr2 in EMT induction.
Project description:Aims/hypothesis: Duct cells isolated from adult human pancreas can be reprogrammed to express islet beta cell genes by adenoviral transduction of the developmental transcription factor neurogenin3 (Ngn3). In this study we aimed to fully characterize the extent of this reprogramming and intended to improve it. Methods: The extent of the Ngn3-mediated duct-to-endocrine cell reprogramming was measured employing genome wide mRNA profiling. By modulation of the Delta-Notch signaling or addition of pancreatic endocrine transcription factors Myt1, MafA and Pdx1 we intended to improve the reprogramming. Results: Ngn3 stimulates duct cells to express a focused set of genes that are abundant in islet endocrine cells and/or neural tissues. This neuro-endocrine shift, however, covers a minor fraction (5%) of the estimated genome-wide transcriptome difference between duct and islet endocrine cells. Interestingly, transduction of exogenous Ngn3 activates endogenous Ngn3 suggesting auto-activation of this gene. Furthermore, pancreatic endocrine reprogramming of human duct cells can be moderately enhanced by inhibition of Delta-Notch signaling as well as by co-expressing the transcription factor Myt1, but not MafA and Pdx1. Conclusions/interpretation: The results provide further insight into the plasticity of adult human duct cells and suggest measurable routes to enhance Ngn3-mediated in vitro reprogramming protocols for regenerative beta cell therapy in diabetes. We used Affymetrix HG133A and HG133B to get a comprehensive view on the reprogramming potential in vitro of human pancreatic duct cell cultures (n=3-4) at 3 and 14/20 days after ectopic adenoviral expression of murine neurogenin 3 as compared to GFP-expressing control vectors. The microarray analysis was performed on 3 independent samples that each contained RNA extracted from a pool of 3 independent donor pancreata. The total number of non-selected donor organs is 9. Transcripts were considered as differentially regulated by Ngn3 when 1.5 fold (LCB, unpaired P < 0.05) up- or down-regulated in AdGFP-Ngn3 versus AdGFP controls, at 3 and/or 14 dpi. Transcripts that showed differential expression between day 3 and day 14 in AdGFP-Ngn3 duct cells but not in AdGFP control cells, were also considered Ngn3-regulated
Project description:To get insight into the mechanisms of MCL1-induced survival and transformation, we screened 41,000 human genes in a genome-wide gene expression profile analysis of MCL1 over-expressing B-NHL cells. Keywords: MCL1-induced gene expression