Project description:H9 human pluripotent stem cells were grown in chemically defined media with Activin A and FGF2. Four 10cm plates with 70% confluency were used per sample. Cells were cross-linked by adding a final concentration of 1% PFA into culture media and incubated for 10 min at RT for Cyclin D1 ChIP. ChIP-seq experiment was performed in duplicate.
Project description:Genomic aberrations of Cyclin D1 (CCND1) and CDK4 in neuroblastoma indicate that dysregulation of the G1 entry checkpoint is an important cell cycle aberration in this pediatric tumor. Here we report that analysis of Affymetrix expression data of primary neuroblastic tumors shows an extensive over-expression of Cyclin D1 and CDK4 which correlates with histological subgroups and prognosis respectively. Immunohistochemical analysis demonstrated an over-expression of Cyclin D1 in neuroblasts and a low Cyclin D1 expression in all cell types in ganglioneuroma. This suggests an involvement of G1 regulating genes in neuronal differentiation processes which we further evaluated using RNA interference against Cyclin D1 and its kinase partner CDK4 in several neuroblastoma cell lines. This resulted in pRb pathway inhibition as shown by an almost complete disappearance of CDK4 specific pRb phosphorylation; reduction of E2F transcriptional activity and a decrease of Cyclin A protein levels. The Cyclin D1 and CDK4 knock-down resulted in a significant reduction in cell proliferation, a G1 specific cell cycle arrest and moreover an extensive neuronal differentiation. Affymetrix microarray profiling of siRNA treated cells revealed a shift in expression profile towards a neuronal phenotype. Several new potential downstream players are identified. We conclude that neuroblastoma functionally depend on over-expression of G1 regulating genes to maintain their undifferentiated phenotype. Keywords: Neuroblastoma, CCND1, Cyclin D1, CDK4
Project description:Analysis of mammary glands from tet-inducible(rtTA) transgenic mice expressing cyclin D1 using Affymetrix Mouse Gene 1.0 ST GeneChip arrays. MMTV-rtTA transgenic mice (MMTV-Mouse Mammary Tumor Virus promoter) were cross-mated to cyclin D1 transgenic mice under control of tet operon. 8-week-old tetracycline-inducible cyclin D1/rtTA bi-transgenic pregnant female mice (12 days postcoitus) were treated with doxycycline through drinking water supplementation at a final concentration of 2 mg/ml. Control mice were rtTA transgenics alone and treated in the same manner. After 7 days of doxycycline treatment, the mice were sacrificed and mammary glands taken for RNA isolation. Results provide insight into the in vivo gene expression pattern regulated by cyclin D1 through acute induction. Analysis of mammary glands from MMTV-cyclin D1/WT and MMTV-cyclin D1/KE using Affymetrix Mouse 430A v2.0 GeneChip arrays. Cyclin D1 point mutant, cyclin D1/KE K112E (K112E) contains a lysine to glutamine substitution at amino acid position 112. cyclin D1. The cyclin D1/KE mutant fails to induce cyclin D1-dependent kinase activity. Female MFD1, MFD1-KE, and WT mice were monitored twice weekly, up to 760 days, for the development of palpable tumors. Those developing palpable tumors were sacrificed within a week of tumor detection. Tumors were dissected and portions snap frozen for RNA isolation. Results provide insight into the in vivo gene expression pattern regulated by cyclin D1 that is kinase independent.
Project description:Analysis of mammary glands from tet-inducible(rtTA) transgenic mice expressing cyclin D1 using Affymetrix Mouse Gene 1.0 ST GeneChip arrays. MMTV-rtTA transgenic mice (MMTV-Mouse Mammary Tumor Virus promoter) were cross-mated to cyclin D1 transgenic mice under control of tet operon. 8-week-old tetracycline-inducible cyclin D1/rtTA bi-transgenic pregnant female mice (12 days postcoitus) were treated with doxycycline through drinking water supplementation at a final concentration of 2 mg/ml. Control mice were rtTA transgenics alone and treated in the same manner. After 7 days of doxycycline treatment, the mice were sacrificed and mammary glands taken for RNA isolation. Results provide insight into the in vivo gene expression pattern regulated by cyclin D1 through acute induction. Analysis of mammary glands from MMTV-cyclin D1/WT and MMTV-cyclin D1/KE using Affymetrix Mouse 430A v2.0 GeneChip arrays. Cyclin D1 point mutant, cyclin D1/KE K112E (K112E) contains a lysine to glutamine substitution at amino acid position 112. cyclin D1. The cyclin D1/KE mutant fails to induce cyclin D1-dependent kinase activity. Female MFD1, MFD1-KE, and WT mice were monitored twice weekly, up to 760 days, for the development of palpable tumors. Those developing palpable tumors were sacrificed within a week of tumor detection. Tumors were dissected and portions snap frozen for RNA isolation. Results provide insight into the in vivo gene expression pattern regulated by cyclin D1 that is kinase independent. Two separate control mice were positive for MMTV-rtTA transgene compared to 3 separate cyclin D1/rtTA bitransgenic female mice and 3 separate cyclin D1 KE mutant/rtTA bitransgenic female mice (Mouse Gene 1.0 ST arrays). Three separate control WT FvBmice were compared to three MMTV-cyclin D1/WT and 3 MMTV-cyclin D1/KE mice (Mouse 430A v2.0 arrays).
Project description:Genomic aberrations of Cyclin D1 (CCND1) and CDK4 in neuroblastoma indicate that dysregulation of the G1 entry checkpoint is an important cell cycle aberration in this pediatric tumor. Here we report that analysis of Affymetrix expression data of primary neuroblastic tumors shows an extensive over-expression of Cyclin D1 and CDK4 which correlates with histological subgroups and prognosis respectively. Immunohistochemical analysis demonstrated an over-expression of Cyclin D1 in neuroblasts and a low Cyclin D1 expression in all cell types in ganglioneuroma. This suggests an involvement of G1 regulating genes in neuronal differentiation processes which we further evaluated using RNA interference against Cyclin D1 and its kinase partner CDK4 in several neuroblastoma cell lines. This resulted in pRb pathway inhibition as shown by an almost complete disappearance of CDK4 specific pRb phosphorylation; reduction of E2F transcriptional activity and a decrease of Cyclin A protein levels. The Cyclin D1 and CDK4 knock-down resulted in a significant reduction in cell proliferation, a G1 specific cell cycle arrest and moreover an extensive neuronal differentiation. Affymetrix microarray profiling of siRNA treated cells revealed a shift in expression profile towards a neuronal phenotype. Several new potential downstream players are identified. We conclude that neuroblastoma functionally depend on over-expression of G1 regulating genes to maintain their undifferentiated phenotype. Experiment Overall Design: The Cell line IMR-32 at time point 0 and transiently transfected with siRNA against GFP, Cyclin D1 and CDK4 at time point 48 hours. All experiments are biological triplicates.
Project description:Mantle cell lymphoma (MCL) is an aggressive B-cell neoplasm characterized by the t(11;14)(q13;q32) translocation leading to cyclin D1 overexpression. Cyclin D1 is a major cell cycle regulator and also has a role in transcription, but the effect of the latter in tumorigenesis remains largely unknown. Here, we investigated the transcriptional role of cyclin D1 in MCL and its impact on the pathogenesis of this neoplasm. Integrating genome-wide expression analysis of cyclin D1-silenced and overexpressing cells with cyclin D1 chromatin binding profiles, we identified a cyclin D1-activated transcriptional program in MCL cells. We used microarrays to analyze the genome-wide expression modulation in cyclin D1 overexpression models established in the cyclin D1-negative lymphoblastoid cell line JVM13.
Project description:Mantle cell lymphoma (MCL) is an aggressive B-cell neoplasm characterized by the t(11;14)(q13;q32) translocation leading to cyclin D1 overexpression. Cyclin D1 is a major cell cycle regulator and also has a role in transcription, but the effect of the latter in tumorigenesis remains largely unknown. Here, we investigated the transcriptional role of cyclin D1 in MCL and its impact on the pathogenesis of this neoplasm. Integrating genome-wide expression analysis of cyclin D1-silenced and overexpressing cells with cyclin D1 chromatin binding profiles, we identified a cyclin D1-activated transcriptional program in MCL cells.
Project description:Cyclin D1 is an important cell cycle regulator but in cancer its overexpression also increases cellular migration mediated by p27KIP1 stabilization and RhoA inhibition. Recently, a common polymorphism at the exon 4-intron 4 boundary of the human cyclin D1 gene within a splice donor region was associated with an altered risk of developing cancer. Altered RNA splicing caused by this polymorphism gives rise to a variant cyclin D1 isoform termed cyclin D1b, which has the same N-terminus as the canonical cyclin D1a isoform but a distinct C-terminus. Analysis was performed of mouse cyclin D1 knockout 3T3 cells infected with splice variants of cyclin D1. 3T3 cells transduced with retroviral vectors expressing each cyclin D1 isoform were processed for expression analysis. Keywords: Cancer associated risk factor
Project description:We examined the transcriptional function of cyclin D1 in mouse development using two approaches. First, we queried association of cyclin D1 with the genome of E14.5 mouse embryos using ChIP-on-chip approach. We observed binding of cyclin D1 to several promoter regions. Second, we compared gene expression profiles between wild-type and cyclin D1-null retinas. We observed several transcripts with altered levels in cyclin D1-null organs. This SuperSeries is composed of the SubSeries listed below.
Project description:Cyclin D1 belongs to the core cell cycle machinery1, and it is frequently overexpressed in human cancers2. The full repertoire of cyclin D1 functions in normal development and in cancer cells is currently unknown. To address this question, here we introduce a novel approach that allows one to determine the set of cyclin D1-interacting proteins (D1 “interactome”) and cyclin D1-bound genomic fragments (D1 “cistrome”) in essentially any mouse organ, at any point of development or at any stage of cancer progression. Using this approach, we detected several novel tissue-specific interactors of cyclin D1. A significant number of these partners represent proteins involved in transcription. We show, using genome-wide location analysis3, that cyclin D1 occupies promoters of a very large number of genes in the developing mouse, where it binds in close proximity to transcription start sites. Bioinformatics analyses of cyclin D1-bound genomic segments in the developing embryo revealed DNA recognition sequences for several transcription factors. By querying SAGE libraries4, promoter CpG content5 and gene expression profiles of cyclin D1-null organs, we demonstrate that cyclin D1 binds promoters of highly expressed genes, and that it functions to activate or to repress gene expression in vivo. Analyses of cyclin D1 transcriptional targets reveal that cyclin D1 contributes to cell proliferation by upregulating genes required for S-phase entry and progression. Hence, cyclin D1 plays a broad transcriptional regulatory function in vivo during normal mouse development.