Project description:SKBR-3 cells were transfected with Luciferase siRNA or VE-cadherin siRNA and then treated with 10-7M retinoic acid (RA) for 48 hours.
Project description:Polycomb-mediated repression of Dkk-1 activates Wnt signaling and enhances tumorigenic potential of lung cancer cells following tobacco smoke exposure Experiment Overall Design: microarray techniques were used to examine proliferation and gene expression in A549 and Calu-6 lung cancer cells cultured in normal media with or without tobacco smoke condensate (TSC)
Project description:As we clarified before, the FOXP3 gene is an X-linked tumor suppressor gene in mammary carcinoma in both human and mouse. We also clarified that the ERBB2 and SKP2 oncogenes were transcriptionally under control of the FOXP3 gene product in mammary epithelial cells. In order to further clarify the FOXP3 down stream target genes in human breast cancer cells, we planed to conduct a microarray analysis of FOXP3-induced gene expression profiling. MCF7, a human breast cancer cell line, with FOXP3-tet-off system was cultured with and without Doxycyclin for 2 days. In the MCF7 cell cultured without Dox, the FOXP3 transcript was significantly induced as compared to the MCF7 cultured with Dox. Total RNA from MCF7 with and wihtout Dox were extracted by Qiagen's RNeasy column and they were applied to Affymetrix Human U133 2.0 array according to the manufacture's protocol. We clarified as yet unknown FOXP3 target genes in human epithelial cells, e.g., the p21 gene, by this analysis.
Project description:ErbB receptor ligands, epidermal growth factor (EGF) and heregulin (HRG), induce dose-dependent transient and sustained intracellular signaling, proliferation and differentiation of MCF-7 breast cancer cells, respectively. In an effort to delineate the ligand-specific cell determination mechanism, we investigated time-course gene expressions induced by EGF and HRG that induce distinct cellular phenotypes in MCF-7 cells. To analyze the effects of ligand dosage and time for the gene expression independently, we developed a statistical method for decomposing the expression profiles into the two effects. Our results indicated that signal transduction pathways devotedly convey quantitative properties of the dose-dependent activation of ErbB receptor to early transcription. The results also implied that moderate changes in the expression levels of numbers of genes, not the predominant regulation of a few specific genes, might cooperatively work at the early stage of the transcription for determining the cell fate. However, the EGF- and HRG-induced distinct signal durations resulted in the ligand-oriented biphasic induction of proteins after 20 min. The selected gene list and HRG-induced prolonged signaling suggested that transcriptional feedback to the intracellular signaling results in a graded to biphasic response in the cell determination process, and that each ErbB receptor is inextricably responsible for the control of amplitude and duration of cellular biochemical reactions. MCF-7 human breast cancer cells were incubated from 5min to 90min after administration of different concentrations of the growth hormones (epidermal growth factor (EGF) and heregulin (HRG)). Control was set as growth hormone non-treated cells. For each growth hormone, one control was used.
Project description:MCF7 cells were treated with DMSO or 100 nM Dioxin for 16 hr. Gene expression changes were quantified by microarray analyses. Experiment Overall Design: HU133A and B arrays were used to quantify differences in RNA after treatment with 100 nM dioxin for 16 h. The experiment was repeated 3 times.
Project description:TGF-beta has an oncogenic response in glioblastoma and it is considered to be a therapeutic target. We evaluated the effect of TGF-beta inhibition in glioblastoma. Differential gene expression analysis of patient-derived primary cultured glioblastoma cells treated with the TGF-beta receptor inhibitor, LY2109761 11 patient-derived cell cultures from 11 patients were treated with 2microM of the TGF-beta receptor inhibitor, LY2109761, for 3 hours or left untreated and RNA was isolated and microarray analysis was performed
Project description:Purpose: A number of microarray studies have reported distinct molecular profiles of breast cancers (BC): basal-like, ErbB2-like and two to three luminal-like subtypes. These were associated with different clinical outcomes. However, although the basal and the ErbB2 subtypes are repeatedly recognized, identification of estrogen receptor (ER)-positive subtypes has been inconsistent. Refinement of their molecular definition is therefore needed. Materials and methods: We have previously reported a gene-expression grade index (GGI) which defines histological grade based on gene expression profiles. Using this algorithm, we assigned ER-positive BC to either high or low genomic grade subgroups and compared these to previously reported ER-positive molecular classifications. As further validation, we classified 666 ER-positive samples into subtypes and assessed their clinical outcome. Results: Two ER-positive molecular subgroups (high and low genomic grade) could be defined using the GGI. Despite tracking a single biological pathway, these were highly comparable to the previously described luminal A and B classification and significantly correlated to the risk groups produced using the 21-gene recurrence score. The two subtypes were associated with statistically distinct clinical outcome in both systemically untreated and tamoxifen-treated populations. Conclusions: The use of genomic grade can identify two clinically distinct ER-positive molecular subtypes in a simple and highly reproducible manner across multiple datasets. This study emphasizes the important role of proliferation-related genes in predicting prognosis in ER-positive BC. Experiment Overall Design: dataset of microarray experiments from primary breast tumors used to assess the reationship between GGI, molecular subtypes, and tamoxifen resistance. Experiment Overall Design: No replicate, no reference sample.
Project description:The estrogen receptor is the master transcriptional regulator of breast cancer phenotype and the archetype of a molecular therapeutic target. We mapped all estrogen receptor and RNA polymerase II binding sites on a genome-wide scale, identifying the authentic cis binding sites and target genes, in breast cancer cells. Combining this unique resource with gene expression data demonstrates distinct temporal mechanisms of estrogen-mediated gene regulation,particularly in the case of estrogen-suppressed genes. Furthermore, this resource has allowed the identification of cis-regulatory sites in previously unexplored regions of the genome and the cooperating transcription factors underlying estrogen signaling in breast cancer. Experiment Overall Design: This Series currently contains the gene expression data accompaning Carroll JS et al. Nature Genetics 38,1289-1297(2006). MCF7 cells were stimulated with 100 nM estrogen for 0, 3, 6, or 12h. All experiments were performed in triplicate.
Project description:"The integral role of p53 in tumor suppression has promted many laboratories to perform extensive analyses of signaling pathways downstream of the p53 family of sequence-specific DNA binding transcription factors (p53 and its homologs p63 and p73). Despite the ability of p73 to regulate many p53 family target genes, little is known about the specific pathways that modulate p73 during development, tumorigenesis and tumor therapy. In this study we present a gene signature-based approach for connecting signaling pathways to transcription factors, as exemplified by p73. We generated a p73 gene signature by integrating whole-genome chromatin immunoprecipitation and expression profiling. Experiment Overall Design: H1299 lung carcinoma cells were infected with p73 expressing or control adenovirus for 5 h and then harvested."