Dataset Information

Molecular profiling of the of conjunctival epithelial side population cells

ABSTRACT: Side population (SP) cells isolated from limbal and conjunctival epithelia derive from cells that are slow cycling in vivo, a known feature of tissue stem cells. The purpose of this study was to define the molecular signature of the conjunctival side population cells by global differential gene expression to identify markers and signaling pathways associated with this cell phenotype. Four overnight cultures of freshly isolated human conjunctival epithelial cells stained with Hoechst 3342 were cytometrically sorted into SP and non-SP cohorts. RNA was isolated and processed for microarray analysis using a commercial oligonucleotide array representing more than 55,000 transcripts derived from about 30,000 different genes. Selected microarray results were validated at the gene and protein levels by quantitative PCR, and immunological methods. Data mining methods were used to identify cellular processes relevant for stem cell function. Comparative analysis of transcripts expression based on expression levels and present/absent software calls across 4 replicate experiments identified 16993 expressed conjunctival epithelial transcripts including 10,266 unique known genes. Of those genes, 1254 and 363 were over expressed (> 2-fold ) or under expressed (< 0.5-fold), respectively, in the SP. The overexpressed set included genes coding for non-epithelial genes (e.g., CD62E/E-selectin and CD93), genes that have been associated with stem cell function in other cellular systems, including several homeodomain genes and genes whose over- or under-expression may underpin the stem cell slow cycling phenotype ( e.g., dual specificity phosphatases and cyclin kinases).

ORGANISM(S): Homo sapiens

PROVIDER: GSE12631 | GEO | 2009/10/30

SECONDARY ACCESSION(S): PRJNA112805

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Side population (SP) cells isolated from limbal and conjunctival epithelia derive from cells that are slow cycling in vivo, a known feature of tissue stem cells. The purpose of this study was to define the molecular signature of the conjunctival side population cells by global differential gene expression to identify markers and signaling pathways associated with this cell phenotype. Four overnight cultures of freshly isolated human conjunctival epithelial cells stained with Hoechst 3342 were cytometrically sorted into SP and non-SP cohorts. RNA was isolated and processed for microarray analysis using a commercial oligonucleotide array representing more than 55,000 transcripts derived from about 30,000 different genes. Selected microarray results were validated at the gene and protein levels by quantitative PCR, and immunological methods. Data mining methods were used to identify cellular processes relevant for stem cell function. Comparative analysis of transcripts expression based on expression levels and present/absent software calls across 4 replicate experiments identified 16993 expressed conjunctival epithelial transcripts including 10,266 unique known genes. Of those genes, 1254 and 363 were over expressed (> 2-fold ) or under expressed (< 0.5-fold), respectively, in the SP. The overexpressed set included genes coding for non-epithelial genes (e.g., CD62E/E-selectin and CD93), genes that have been associated with stem cell function in other cellular systems, including several homeodomain genes and genes whose over- or under-expression may underpin the stem cell slow cycling phenotype ( e.g., dual specificity phosphatases and cyclin kinases). Experiment Overall Design: Whole human conjunctivae from unidentifiable cadaver donors, aged 55 to 65, were obtained from the National Disease Research Interchange (NDRI, Philadelphia, PA) within 48 hours of collection. No donor details apart from age, sex, and cause of death were released. The use of human tissue in the study was in accordance with the provisions of the Declaration of Helsinki and sanctioned by the Institutional Review Board. Fresh rabbit tissue was obtained from local abattoirs within one hour of sacrifice. Unless stated otherwise all reagents were procured from Sigma (St. Louis, Mo). Experiment Overall Design: Eight microarray experiments using side population (Hoechst 33342-transporting cells; SP) or non side population (Hoechst 33342-stained cells; nSP) cells from four cadavers.

Project description:The recent identification of cancer stem cells (CSCs) in multiple human cancers provides a new inroad to understanding tumorigenesis at the cellular level. CSCs are defined by their characteristics of self-renewal, multipotentiality, and tumor initiation upon transplantation. By testing for these defining characteristics, we provide evidence for the existence of CSCs in a transgenic mouse model of glioma, S100Ã-verbB;Trp53. In this glioma model, CSCs are enriched in the side-population (SP) cells. These SP cells have enhanced tumor-initiating capacity, self-renewal, and multipotentiality compared to non-SP cells from the same tumors. Furthermore, gene expression analysis comparing FACS-sorted cancer SP cells to non-SP cancer cells and normal neural SP cells identified 45 candidate genes that are differentially expressed in glioma stem cells. We validated the expression of two genes from this list (S100a4 and S100a6) in primary mouse gliomas and human glioma samples. Analyses of xenografted human GBM (glioblatoma multiforme) cell lines and primary human glioma tissues show that S100A4 and S100A6 are expressed in a small subset of cancer cells and that their abundance is positively correlated to tumor grade. In conclusion, this study shows that CSCs exist in a mouse glioma model, suggesting that this model can be used to study the molecular and cellular characteristics of CSCs in vivo and to further test the cancer stem cell hypothesis. Experiment Overall Design: This study features two factors, injected cell origin (either tumorsphere or neurosphere) and FACS cell population (either side population or non-side population cells). There were two different tumorspheres, labeled 3447 and 4346 that were isolated from brain tumors in S100beta-verbB;p53-/- or S100beta-verbB;p53+/- mice. The tumorspheres were injected separately into the brains of NOD.Cg-Prkdc<scid>Il2rg<tm1Wjl>/SzJ mice to generate biological triplicates of each primary tumor. Tumorspheres were isolated and cultured before FACS sorting to obtain side population and non-side population cells. As a control, untransformed neurospheres from three independent S100beta-verbB;p53-/- or S100beta-verbB;p53+/- mice were isolated, cultured, and FACS sorted to obtain side population and non-side population cells. Side population and non-side population cells cultured from three mice injected with the 3447 cultured tumorspheres were assayed for gene expression (six samples). Side-population stem cells cultured from three mice injected with the 4346 cultured tumorspheres were assayed for gene expression (three samples). Side-population and non-side population cells cultured from three mice injected with the neurospheres were assayed for gene expression (six samples).

Dataset Information

Molecular profiling of the of conjunctival epithelial side population cells

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure