Expression data of mammary epithelial cells during the epithelial-mesenchymal transition
ABSTRACT: The EMT program allows epithelial cells to become endowed with motility, invasiveness and stem cell traits. We investigated difference in signaling networks that are differentially utilized in EMTed and non-EMTed cells, thereby identifying therapeutic targets that are unique to EMT/cancer stem cells. We expressed the EMT transcription factors, Twist, Snail and Slug in HMLE human mammary epithelial cells, and compared their gene expression with parental cells. We identified kinases that are more differentially regulated between the epithelial and mesenchymal cell state.
Project description:We quantified protein expression changes between epithelial and mesechymal stages in immortalized human mammary epithelial cells (HMLE). Epithelial–mesenchymal transition is induced by expressing an EMT-TF, Twist.
Project description:Regulation of cell-cell junction formation and regulation of cell migration were enriched among EMT (Epithelial-Mesenchymal Transition)-associated alternatively splicing events. Our analysis suggested that most EMT-associated alternative splicing events are regulated by one or more members of the RBFOX, MBNL, CELF, hnRNP or ESRP classes of splicing factors. The EMT alternative splicing signature was confirmed in human breast cancer cell lines, which could be classified into basal and luminal subtypes based exclusively on their EMTassociated splicing pattern. Expression of EMT-associated alternative mRNA transcripts was also observed in primary breast cancer samples, indicating that EMT-dependent splicing changes occur commonly in human tumors. The functional significance of EMT-associated alternative splicing was tested by expression of the epithelial-specific splicing factor ESRP1 or depletion of RBFOX2 in mesenchymal cells, both of which elicited significant changes in cell morphology and motility towards an epithelial phenotype, suggesting that splicing regulation alone can drive critical aspects of EMT-associated phenotypic changes. The molecular description obtained here may aid in the development of new diagnostic and prognostic markers for analysis of breast cancer progression. Examination of transcriptomes of HMLE/Twist-ER before and after induction of EMT by tamoxifen
Project description:Background: The well-characterized function of the transcriptional repressor, Slug, is to promote EMT and tumor invasion/metastasis by down-regulating E-cadherin expression. In this study, we investigated the significance of Slug during the S phase. Method: Slug mRNA expression was isolated from thymidine-arrested CL1-5/AS2neo (control) and CL1-5/AS2neo-Slug-WT stable cells. The Agilent oligonucleotide microarray analysis was performed to identify Slug downstream genes. Results: Overexpression of Slug inhibited lung [3H]-thymidine incorporation and delayed S phase progression. By using Agilent microarray we have identified panel of genes altered by Slug overexpression. Slug can down-regulate target genes about cell cycle networks for DNA replication, DNA replication checkpoint and genomic stability, such as TOP1, ORC4, RFC3, and Rad17. Conclusions: the multifaceted role of Slug in cancer progression by controlling the epithelial-mesenchymal transition and genome stability. Two-condition experiment, Vector vs. Slug overexpression cells. The cDNAs encoding full-length human Slug were amplified and subcloned into lentiviral pLKO_AS2.neo which generated full-length Slug. Vector control or Slug lentivirus were transduced into CL1-5 cells and Gentamycin was used to select stable cells.
Project description:Gene expression profiling to determine transcriptome changes following Snail or Slug expression in MCF-7 breast cancer cells Samples were isolated in three biological replicates for microarray analysis. Four MCF-7 breast cancer cell subsets: MCF-7(untreated), MCF-7 (with Control adenovirus), MCF-7 (with Snail adenovirus) and MCF-7 (with Slug adenovirus). RNA was purified on Day 0 for untreated, and on days 1,2 and 4 for the remaining three subsets for gene expression profiling on microarray.
Project description:The epithelial-mesenchymal transition (EMT) is thought to be essential for cancer metastasis. While chromatin remodeling is involved in EMT, histone variants contribution in EMT remains poorly investigated. Recently, we showed that silencing or removal of the histone variant H2A.X induced mesenchymal-like characteristics, including activation of the EMT transcription factors, Slug and ZEB1, in human colon cancer cells. Here, we provide the evidence that H2A.X loss in human non-tumorigenic breast cell line MCF10A results in a robust EMT activation, as substantiated by a genome-wide expression analysis. Cells deficient for H2A.X exhibit enhanced migration and invasion, along with an activation of a set of mesenchymal genes and a concomitant repression of epithelial genes. In the breast model, the EMT-related transcription factor Twist1 cooperates with Slug to regulate EMT upon H2A.X loss. Of interest, H2A.X expression level tightly correlates with Twist1, and to a lesser extent with Slug in the panel of human breast cancer cell lines of the NCI-60 datasets. These new findings indicate that H2A.X is involved in the EMT processes in cells of different origins but pairing with transcription factors for EMT may be tissue specific. Overall design: 10 samples in total including 5 replicates of parental MCF10A cells and 5 replicates of H2A.X knockout cells.
Project description:Two engineered HMLE cell lines representing various degrees of EMT were treated with a drug in development to target and inhibit SNAIL interaction with PTP53, called GN-25 total RNA was isolated and analyzed in an Agilent two-color experiment. Four biological replicates of each condition were directly compared, GN25 treated compared to untreated reference The impact of GN-25 on gene expression was investigated using two engineered HMLE cell lines: one stably overexpressing Kras another stably overexpressing Kras and SNAIL
Project description:Investigation of whole genome gene expression level changes in hepatocellular carcinoma cell line hepG2 in regular culture, hepG2-slug in regular culture and hepG2-slug on Matrigel. Whole genome gene expression level changes have been compared in hepatocellular carcinoma cell line hepG2 in regular culture, hepG2-slug in regular culture and hepG2-slug on Matrigel. Roche NimbleGen micro-array analysis was employed to assess global genome expression in HepG2 in regular culture, HepG2-slug in regular culture and HepG2-slug on Matrigel. The results demonstrated that the up-regulated genes and the down-regulated genes increased significantly when HepG2-slug cells with VM forming ablity were cultured on Matrigel and formed VM.
Project description:Epithelial-Mesenchymal Transition (EMT) is thought to contribute to cancer metastasis, but its underlying mechanisms are not well understood. To define early steps in this cellular transformation, we analyzed human mammary epithelial cells with tightly regulated expression of Snail-1, a master regulator of EMT. Following Snail-1 induction, epithelial markers were repressed within 6 hours and mesenchymal genes induced at 24 hours. Snail-1 binding to its target promoters was transient (6-48 hours) despite continued protein expression and it was followed by both transient and long-lasting chromatin changes. To generate a potent reversible EMT-inducing stimulus, we created a Snail-1 retroviral expression construct, using a fused estrogen receptor (ER) response element to mediate regulation by exogenous 4-hydroxy-tamoxifen (4-OHT). Since Snail-1 protein stability and nuclear localization are suppressed by GSK3-beta-mediated phosphorylation, we substituted the six targeted amino acids (ER-Snail-1(6SA)), thus conferring constitutive activity to the induced protein (Zhou et al., 2004, Pubmed ID 15448698). Infection of non-transformed, immortalized human mammary epithelial MCF10A cells with ER-Snail-1(6SA), followed by treatment with 4-OHT, triggered morphological and biomarker characteristics of EMT. At 0, 6, 48 and 120 hours after beginning exposure to 4-OHT in ethanol (or, for controls, ethanol only) we ChIPed Snail-1 and 6 histone marks. We perfomed two replicates of each, except we only had one replicate of H3K27Me3 at 6 hours.
Project description:The epithelial-mesenchymal transition (EMT), considered essential for metastatic cancer, has been a focus of much research, but important questions remain. Here, we show that silencing or removing H2A.X, a histone H2A variant involved in cellular DNA repair and robust growth, induced mesenchymal-like characteristics including activation of EMT transcription factors, Slug and ZEB1, in HCT116 human colon cancer cells. Ectopic H2A.X re-expression partially reversed these changes; as did silencing Slug and ZEB1. In an experimental metastasis model, the HCT116 parental and H2A.X-null cells exhibited similar metastases levels, but the cells with re-expressed H2A.X exhibited substantially elevated levels. We surmise that H2A.X re-expression led to partial EMT reversal and increased robustness in the HCT116 cells, permitting them to both form tumors and to metastasize. In a human adenocarcinoma panel, H2A.X levels correlated inversely with Slug and ZEB1 levels. Together, these results point to H2A.X as a novel regulator of EMT. Overall design: 9 samples in total including 4 replicates of control shRNA and 5 replicates of shH2A.X.
Project description:Microarrays were used to determine relative global gene expression changes upon introduction of EMT-inducing or control vectors. Experimentally immortalized HMLE breast epithelial cells were retrovirally transduced in culture with vectors encoding EMT-inducing genes or control vectors. There were three biologic replicates for each genetic perturbation condition. After treatment, the cells were selected and expanded, after which total RNA was isolated and subjected to microarray analysis.