Dataset Information

Molecular mechanisms involved in adipose tissue-derived stromal cell hepatic conversion

ABSTRACT: Background: Adipose tissue-derived stromal cells (ATSCs) hold great promises in regenerative medicine, due to their easy retrieval, high proliferative capacity, and multi-lineage differentiation potential. In the last decade, several studies have reported the plasticity of ATSCs toward a hepatic fate. Nonetheless, the molecular mechanisms underlying the conversion from a mesenchymal to an epithelial phenotype remain poorly understood. Aim: In this study, we compared the full genome expression profiles of ATSCs cultured for 4 weeks under pro-hepatogenic conditions to undifferentiated ATSCs, in order to depict the molecular events involved in ATSC hepatic transdifferentiation. Methods: Molecular analysis was performed using the Affymetrix human focus arrays. Sets of differentially expressed genes were functionally categorized in order to understand which pathways drive the hepatic conversion and interesting target genes were validated by Q-PCR. Results: We showed that ATSC-derived hepatocyte-like cells activate several genes associated with specific liver functions, including protein metabolism, innate immune response regulation, and biodegradation of toxic compounds. Furthermore, microarray analysis highlighted the downregulation of several transcripts involved in stemness maintenance along with genes associated with a mesenchymal phenotype. Conclusion: Taken together, our data suggest that the in vitro system used in this study drove ATSCs toward a hepatic conversion through a subtle regulation of molecular pathways controlling stem cell properties and lineage commitment that promote mesenchymal-epithelial-transition.

ORGANISM(S): Homo sapiens

PROVIDER: GSE18201 | GEO | 2009/12/15

SECONDARY ACCESSION(S): PRJNA119559

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Background: Adipose tissue-derived stromal cells (ATSCs) hold great promises in regenerative medicine, due to their easy retrieval, high proliferative capacity, and multi-lineage differentiation potential. In the last decade, several studies have reported the plasticity of ATSCs toward a hepatic fate. Nonetheless, the molecular mechanisms underlying the conversion from a mesenchymal to an epithelial phenotype remain poorly understood. Aim: In this study, we compared the full genome expression profiles of ATSCs cultured for 4 weeks under pro-hepatogenic conditions to undifferentiated ATSCs, in order to depict the molecular events involved in ATSC hepatic transdifferentiation. Methods: Molecular analysis was performed using the Affymetrix human focus arrays. Sets of differentially expressed genes were functionally categorized in order to understand which pathways drive the hepatic conversion and interesting target genes were validated by Q-PCR. Results: We showed that ATSC-derived hepatocyte-like cells activate several genes associated with specific liver functions, including protein metabolism, innate immune response regulation, and biodegradation of toxic compounds. Furthermore, microarray analysis highlighted the downregulation of several transcripts involved in stemness maintenance along with genes associated with a mesenchymal phenotype. Conclusion: Taken together, our data suggest that the in vitro system used in this study drove ATSCs toward a hepatic conversion through a subtle regulation of molecular pathways controlling stem cell properties and lineage commitment that promote mesenchymal-epithelial-transition. Adipose tissue was obtained from 3 patients undergoing partial abdominoplasty. Adipose tissue-derived stromal cells (ATSC) were isolated according to standard procedures, using the in vitro adherence property of these cells. At passage culture 4, ATSC were submitted to an in vitro hepatogenic regimen, consisting of the sequential addition of growth factors. After 1 month of in vitro differentiation, cells were harvested and their transcriptome was compared to control ATSC.

Project description:Bone marrow (BM) has been considered so far the reference source for stromal cells (SC) originally called mesenchymal stem cells. Recently human adult adipose tissue (AT) has been reported as a valuable source for the isolation of cells exerting a mesenchymal-like phenotype. Though both BM- and AT- derived stromal cells (BMSC and ATSC) share similar immuno-phenotype and exhibit multi-lineage potential in vitro, a consensual panel of specific markers is still debated and the precise molecular mechanisms governing their differentiated fate are not fully understood. The aim of this study was to compare the genome wide expression profiles of stromal cells isolated from AT and BM and to emphasize the core of MSC stemness properties. Moreover we focused on the molecular characteristics of ATSC, attempting to reveal their specific features.We identified an overlapping dataset of 190 genes commonly regulated by ATSC and BMSC. Among these, we were able to categorize 6 key biological families that could be regarded as a stemness signature that underlie the self-renewal potential and the ability to generate progenitor cells. In particular, a pivotal role of signalling pathways along with the expression of numerous transcription regulators emerged from this study. Genes specifically modulated in ATSC, suggested that these cells posses anti-oxidative and neuroprotective properties. Taken together, these results provide new hints towards the understanding of the molecular basis of MSC maintenance and suggest that ATSC have interesting properties which could be useful for several potential clinical applications. Experiment Overall Design: Bone marrow and adipose tissue samples were respectively obtained from four long-term disease-free Hodgkin lymphoma patients, during follow-up investigation and from four patients subjected to partial abdominoplasty. In addition, we used in this study a cell line (MRC-5 cells) as control to rule out genes involved in homeostasis and emphasize genes specifically expressed in both types of mesenchymal stem cells. To have results statistically significant, we enrolled four patients for each tissue (4 chips/tissue) and we performed a technical replicate (triplicate) for the MRC-5 cells.

Project description:The possibility of generating neural cells from human bone marrow-derived mesenchymal stem cells by simple in vitro treatments is alluring both conceptually and practically. However, whether phenotypic modulations observed after chemical manipulation of such stem cells truly represent a genuine trans-lineage differentiation remains to be established. We have re-evaluated the effects of a frequently reported biochemical approach, based on treatment with butylated hydroxyanisole and dimethylsulphoxide, to bring about such phenotypic conversion by monitoring the morphological changes induced by the treatment in real time, by analysing the expression of phenotype-specific protein markers and by assessing the modulation of the cells’ transcriptome. Video time-lapse microscopy showed that conversion of mesenchymal stem cells to a neuron-like morphology could be reproduced in normal primary fibroblasts as well as mimicked by addition of drugs eliciting cytoskeletal collapse and disruption of focal adhesion contacts. Analysis of markers revealed that mesenchymal stem cells constitutively expressed multi-lineage traits, including several pertaining to the neural one. However, the applied “neural induction” protocol neither significantly modulated the expression of such markers, nor induced de novo translation of other neural specific proteins. Similarly, global expression profiling of over 21,000 genes demonstrated that gene transcription was poorly affected. Most strikingly, we found that the set of genes whose expression was altered by the inductive treatment did not match the set of genes found to be differentially expressed when comparing untreated mesenchymal stem cells and immature neural tissues. Conversely, by comparing these gene expression profiles with that obtained from comparisons between the same cells and an unrelated non-neural organ, such as liver, we found that the adopted “neural induction” protocol was no more effective in redirecting human mesenchymal stem cells toward a neural phenotype than toward an endodermal hepatic pathway. Keywords: Differentiation analysis

Dataset Information

Molecular mechanisms involved in adipose tissue-derived stromal cell hepatic conversion

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure