This SuperSeries is composed of the SubSeries listed below.
The requirement for cyclin D function in tumor maintenance.
Specimen part, Cell line
View SamplesD-cyclins represent components of cell cycle machinery. To test the efficacy of targeting D-cyclins in cancer treatment, we engineered mouse strains which allow acute and global ablation of individual D-cyclins in a living animal. Ubiquitous shutdown of cyclin D1 or inhibition of cyclin D associated kinase activity in mice bearing ErbB2-driven mammary carcinomas halted cancer progression and triggered tumor-specific senescence, without compromising the animals' health. Ablation of cyclin D3 in mice bearing T-cell acute lymphoblastic leukemias (T-ALL) triggered tumorspecific apoptosis. Such selective killing of leukemic cells can be also achieved by inhibiting cyclin D associated kinase activity in mouse and human T-ALL models. Hence, contrary to what one might expect from ablation of a cell cycle protein, acute shutdown of a D-cyclin leads not only to cell cycle arrest, but it also triggers tumor cell senescence or apoptosis, and it affects different tumor types through distinct cellular mechanisms. Inhibiting cyclin D-activity represents a highly-selective anticancer strategy which specifically targets cancer cells without significantly affecting normal tissues.
The requirement for cyclin D function in tumor maintenance.
Specimen part
View SamplesWe 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.
Transcriptional role of cyclin D1 in development revealed by a genetic-proteomic screen.
No sample metadata fields
View SamplesCyclin 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.
Transcriptional role of cyclin D1 in development revealed by a genetic-proteomic screen.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Canonical and atypical E2Fs regulate the mammalian endocycle.
Age, Specimen part
View SamplesTo understand the underlying cause and mechanisms of changes in hepatocyte ploidy upon Albumin-Cre mediated deletion of E2f7&8 and Mx1-Cre mediated deletion of E2f1,2&3, we analysed global gene expression of 6 weeks and 2 months liver tissues.
Canonical and atypical E2Fs regulate the mammalian endocycle.
Age, Specimen part
View Samples