Differential regulation of Twist1-responsive genes in 4T1 cells
ABSTRACT: Twist1 variants including wildtype Twist1, a non-phosphorylatable mutant Twist1/S42A and a phospho-mimicking mutant Twist1/S42D were expressed in 4T1 cells in which the endogenous Twist1 was depleted. We wanted to use microarray analysis to evaluate those genes that are differentially regulated by Twist1 variants. All cell lines were grown to 70% confluency and total RNA was isolated with Qiagen kit. Each sample was prepared as triplicates. Parental 4T1 cells were used as control.
Project description:Twist1 variants including wildtype Twist1, a non-phosphorylatable mutant Twist1/S42A and a phospho-mimicking mutant Twist1/S42D were expressed in 4T1 cells in which the endogenous Twist1 was depleted. We wanted to use microarray analysis to evaluate those genes that are differentially regulated by Twist1 variants. Overall design: All cell lines were grown to 70% confluency and total RNA was isolated with Qiagen kit. Each sample was prepared as triplicates. Parental 4T1 cells were used as control.
Project description:The present study was designed to identify Mkl1 target genes whose expression requires either the B1 site of Mkl1 and serum response factor (SRF), respectively, or the SAP domain of Mkl1. For this purpose, we obtained the transcriptomes of four stable 4T1 cell lines that either overexpress full length Mkl1-RFP (4T1-FL), Mkl1-RFP with a mutated SRF-interaction site (4T1-mutB1), Mkl1-RFP with a deletion of the SAP domain (4T1-ΔSAP) or an empty vector encoding RFP alone (4T1 control). Stable 4T1 cell lines were grown in triplicates in 0.03% FCS/DMEM medium for 48 h before total RNA was extracted. RNA was converted into labeled cDNA and hybridized to Affymetrix GeneChip Mouse Gene 1.0 ST arrays. RMA normalized expression values were calculated with the affy package from the Bioconductor 2.4 release (1) and differentially expressed genes were identified using moderated t-statistics calculated with the empirical Bayes method as implemented in the Bioconductor limma package (2). To be considered as differentially expressed between 4T1-FL and 4T1-mutB1 or 4T1-∆SAP cells, genes had to pass the filters: adjusted P-value ≤ 0.01 (with Benjamin-Hochberg false discovery correction), a minimum absolute linear fold change difference of 2.0 and a minimum average expression value of 4.0 (log2). References: (1) Gentleman, R., Carey, V., Bates, D., Bolstad, B., Dettling, M., Dudoit, S., Ellis, B., Gautier, L., Ge, Y., Gentry, J., Hornik, K., Hothorn, T., Huber, W., Iacus, S., Irizarry, R., Leisch, F., Li, C., Maechler, M., Rossini, A., Sawitzki, G., Smith, C., Smyth, G., Tierney, L., Yang, J., Zhang, J. (2004) Bioconductor: open software development for computational biology and bioinformatics. Genome Biology 5, R80 (2) Smyth, G. K., Speed, T. (2003) Normalization of cDNA microarray data. Methods 31, 265-273
Project description:Endocrine therapy is the main therapeutic option for patients with estrogen receptor alpha positive (ER+) breast cancer. Nevertheless, most of them become estrogen-independent and relapse after the treatment. Ret is a tyrosine kinase receptor that shows elevated expression levels in ER+ human breast tumors. In this study, we demonstrate that activation of the Ret receptor promotes proliferation as well as cell migration irrespective of endocrine therapy. Microarray data show that Ret activation involves changes in the expression of inflammatory- and motility-related genes. In vivo treatment with a Ret pathway inhibitor in a ER+/Ret+ mouse mammary cancer model, reduces tumor growth and lung metastasis even after endocrine therapy. Additionally, we show a connection between Ret and inflammatory pathways. The pro-inflamatory cytokine IL6 lies at the core of this regulation, which involves a positive feedback loop with IL6 and the Ret pathway reciprocally stimulating each other to further leading metastasis risk. Our findings provide insight into endocrine resistance mechanism and point at the Ret pathway as a potential target for future therapies. In order to model letrozole-sensitive breast cancer we use aromatase expressing MCF7 cells (MCF7/Aro). Six-day treatment (6 days) of cultures with letrozole (L) or fulvestrant (F) reversed the proliferative effects of the exposure to the estrogen (E2) precursor androstenedione (D4A). The addition of only EtOH (E) to the cells was used as control condition of deprivation. Treatment with the Ret ligand GDNF (G) partially rescues the inhibition of estrogen-dependent proliferation in these cells. To go deeper insight into the pathways involved, we decided to perform a microarray following different treatments (1-8: E, E+G, D, D+G, L, L+G, F, F+G) used in proliferation assays. Three biological replicates (rep 1-3) were used to the array.
Project description:In the present study, we investigated the importance of histone deacetylase 6 (HDAC6) for glucocorticoid receptor (GR) mediated effects on glucose metabolism, and its potential as a therapeutic target for the prevention of glucocorticoid (GC)-induced diabetes. Dexamethasone (dex)-induced hepatic glucose output and GR translocation were analysed in wildtype (wt) and HDAC6-deficient (HDAC6ko) mice. The effect of the specific HDAC6-inhibitor tubacin was analysed in-vitro. Wt and HDAC6ko mice were subjected to 3 weeks dex treatment before analysis of glucose and insulin tolerance. HDAC6ko mice showed impaired dex-induced hepatic GR translocation. Accordingly, dex induced expression of a large number of hepatic genes was significantly attenuated in mice lacking HDAC6 and by tubacin in-vitro. Glucose output of primary hepatocytes from HDAC6ko mice was diminished. A significant improvement of dex-induced whole-body glucose intolerance as well as insulin resistance in HDAC6ko mice compared to wt littermates was observed. The present study demonstrates that HDAC6 is an essential regulator of hepatic GC stimulated gluconeogenesis and impairment of whole body glucose metabolism through modification of GR nuclear translocation. Selective pharmacological inhibition of HDAC6 may provide a future therapeutic option against the pro-diabetogenic actions of GCs. In this dataset, we include the expression data obtained from isolated RNA of dissected mouse livers using wildtype and HDAC6 deficient animals which were treated over a timespan of 3 weeks with 1mg/kg dexamethasone and vehicle respectively. These data are used to show the hdac6-deficiency mediated attenuation of several dexamethasone induced genes. 12 samples in total were analyzed. 3 samples of different animals of each group (wt vehicle, wt dexamethasone, hdac6ko vehicle and hdac6ko dexamethasone)
Project description:Dicer proteins function in RNA interference (RNAi) pathways by generating small RNAs (sRNAs). Here we report the solution structure of the C-terminal domain of Schizosaccharomyces pombe Dicer (Dcr1). The structure reveals an unusual double-stranded RNA binding domain (dsRBD) fold embedding a novel zinc-binding motif that is conserved among dicers in yeast. Although the C-terminal domain of Dcr1 still binds nucleic acids, this property is dispensable for proper functioning of Dcr1. In contrast, disruption of zinc coordination renders Dcr1 mainly cytoplasmic and leads to remarkable changes in gene expression and loss of heterochromatin assembly. In summary, our results reveal novel insights into the mechanism of nuclear retention of Dcr1 and raise the possibility that this new class of dsRBDs might generally function in nucleo-cytoplasmic trafficking and not substrate binding. The C-terminal domain of Dcr1 constitutes a novel regulatory module that might represent a potential target for therapeutic intervention with fungal diseases. 12 chips representing 4 different strains. Every condition is represented by three biological replicates
Project description:Molecular comparison between control 4T1 cells with MMP3-low 4T1 cells RNA extracted from biological triplicates of each of the above mentioned cell populations were subjected to microarray analysis
Project description:4T1 is a mammary tumor cell line to which the NFAT1 transcription factor is essential for tumorigenesis and metastasis. control or shRNA transduced 4T1 cells growing in culture were collected and RNA was extracted from each sample and processed for hybridization to Affymetrix arrays.
Project description:Novel therapies targeting cancer stem cells (CSCs), which play critical roles in chemo- and radio-resistance, metastasis, and possibly resistance against cancer immunotherapy including granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced tumor cell vaccines, may provide beneficial clinical outcomes. Here, we used syngeneic immunocompetent mice that allowed precise evaluation of the immunogenicity of the side population (SP) isolated from 4T1 murine breast carcinoma (4T1-SP) cells as putative CSCs. 4T1-SP cells showed various stem cell properties including high capacities for colony formation and tumorigenicity as well as high expression of phosphorylated signal transducer and activator of transcription-3 and vascular endothelial growth factor that are inductive of immune tolerance. Despite these progressive malignant characteristics of 4T1-SP cells, subcutaneous injection of non-transmissible Sendai virus-mediated GM-CSF gene-transduced 4T1-SP (4T1-SP/GM) cells remarkably impaired their tumorigenicity compared with that of the controls. This impairment of tumorigenicity was partially dependent on CD8+ T cells in concert with CD4+ T cells and natural killer cells. Notably, therapeutic vaccinations using irradiated 4T1-SP/GM cells markedly suppressed tumor development of subcutaneously transplanted 4T1-SP cells compared with that of the controls including irradiated 4T1-non-SP/GM cells. Tumor suppression was accompanied by robust accumulation of mature dendritic cells at vaccination sites and systemic Th1-based cellular immunity. Moreover, vaccinations comprising primary 4T1-SP cells isolated from transplanted 4T1-SP tumors elicited antitumor effects. cDNA microarray analysis showed that 4T1-SP cells predominantly expressed genes of cancer-related antigens including cancer/testis antigens. Collectively, we demonstrate that SP cell-based vaccinations induce effective antitumor immunity that may improve the efficacy of SP cell-based immunotherapy. Gene expression profiles were compared between sorted 4T1-SP and 4T1-NSP cells.
Project description:miRNAs profiling of HepG2 cells comparing vector-control treated HepG2 cells with HepG2 cells transfected with Twist1, Bcl-2, and Twist1/Bcl-2 plasmids. Microarray analysis revealed a panel of miRNAs with significant differential expression among these four HCC cell lines. Overall design: In the study presented here, four HCC cell lines ( HepG2-Twist1, HepG2-Bcl-2, HepG2-Twist1/Bcl-2 HCC cell lines, and HepG2-vector cell lines ) was used to analyze miRNA expression profiles. HepG2-Twist1, HepG2-Bcl-2, HepG2-Twist1/Bcl-2 HCC cell lines can stably express Twist1, Bcl-2, and Twist1/Bcl-2, respectively.
Project description:This SuperSeries is composed of the following subset Series: GSE23033: Polycomb function during oogenesis is required for mouse early embryonic development (germinal vesicle oocytes) GSE28710: Polycomb function during oogenesis is required for mouse early embryonic development (2-cell embryos) Refer to individual Series