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Homo sapiens
7 Downloadable Samples
Illumina Genome Analyzer IIx
Description
Melanocytes within benign human nevi are the paradigm for tumor suppressive senescent cells in a pre-malignant neoplasm. These cells typically contain mutations in either the BRAF or N-RAS oncogene and express markers of senescence, including p16. However, a nevus can contain 10s to 100s of thousands of clonal melanocytes and approximately 20-30% of melanoma are thought to arise in association with a pre-existing nevus. Neither observation is indicative of fail-safe senescence-associated proliferation arrest and tumor suppression. We set out to better understand the status of nevus melanocytes. Proliferation-promoting Wnt target genes, such as cyclin D1 and c-myc, were repressed in oncogene-induced senescent melanocytes in vitro, and repression of Wnt signaling in these cells induced a senescent-like state. In contrast, cyclin D1 and c-myc were expressed in many melanocytes of human benign nevi. Specifically, activated Wnt signalling in nevi correlated inversely with nevus maturation, an established dermatopathological correlate of clinical benignancy. Single cell analyses of lone epidermal melanocytes and nevus melanocytes showed that expression of proliferation-promoting Wnt targets correlates with prior proliferative expansion of p16-expressing nevus melanocytes. In a mouse model, activation of Wnt signaling delayed, but did not bypass, senescence of oncogene-expressing melanocytes, leading to massive accumulation of proliferation-arrested, p16-positive non-malignant melanocytes. We conclude that clonal hyperproliferation of oncogene-expressing melanocytes to form a nevus is facilitated by transient delay of senescence due to activated Wnt signaling. The observation that activation of Wnt signaling correlates inversely with nevus maturation, an indicator of clinical benignancy, supports the notion that persistent destabilization of senescence by Wnt signaling contributes to the malignant potential of nevi. Overall design: We used RNA-Seq to detail the global programme of gene expression in human melanoma cell lines
Publication Title
MLL1 is essential for the senescence-associated secretory phenotype.
Sample Metadata Fields
Cell line, Subject
View Samples- Homo sapiens
- 4 Downloadable Samples
- NextSeq500
Description
Oncogene-induced senescence (OIS) and therapy-induced senescence (TIS), while tumor-suppressive, also promote procarcinogenic effects by activating the DNA damage response (DDR), which in turn induces inflammation. This inflammatory response prominently includes an array of cytokines known as the senescence-associated secretory phenotype (SASP). Previous observations link the transcription-associated methyltransferase and oncoprotein MLL1 to the DDR, leading us to investigate the role of MLL1 in SASP expression. Our findings reveal direct MLL1 epigenetic control over proproliferative cell cycle genes: MLL1 inhibition represses expression of proproliferative cell cycle regulators required for DNA replication and DDR activation, thus disabling SASP expression. Strikingly, however, these effects of MLL1 inhibition on SASP gene expression do not impair OIS and, furthermore, abolish the ability of the SASP to enhance cancer cell proliferation. More broadly, MLL1 inhibition also reduces “SASP-like” inflammatory gene expression from cancer cells in vitro and in vivo independently of senescence. Taken together, these data demonstrate that MLL1 inhibition may be a powerful and effective strategy for inducing cancerous growth arrest through the direct epigenetic regulation of proliferation-promoting genes and the avoidance of deleterious OIS- or TIS-related tumor secretomes, which can promote both drug resistance and tumor progression. Overall design: This study consists of a single replicate of RNA-seq from oncogene-induced senescent (or control) IMR90 cells in a MLL1 knockdown (or WT) background, for a total of four samples
Publication Title
MLL1 is essential for the senescence-associated secretory phenotype.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- NextSeq500
Description
Oncogene-induced senescence (OIS) is a tumor suppression mechanism that blocks cell proliferation in response to oncogenic signalling. OIS is frequently accompanied by multinucleation; however, the origin of this is unknown. Here we show that multinucleate OIS cells originated mostly from failed mitosis. Prior to senescence, mutant RasV12 activation in primary human fibroblasts compromised mitosis, associated with abnormal expression of mitotic genes that enter M-phase. Simultaneously, RasV12 activation enhanced survival of damaged mitoses, culminating in extended mitotic arrest and aberrant exit from mitosis via mitotic slippage. ERK-dependent transcriptional up-regulation of Mcl1 was responsible for enhanced slippage of cells with mitotic defects and subsequent cell survival. Importantly, mitotic slippage and oncogene signalling synergistically induced senescence and key senescence regulators p21 and p16. We propose that activated Ras induces transcriptional changes that predispose cells undergoing OIS to mitotic stress and multinucleation. Overall design: We used RNA-seq of IMR90 cells with inducible expression of oncogenic RasV12 that were synchronised in mitosis, to characterise the nature of mitotic defects that lead to multinucleation of oncogene-induced senescent cells
Publication Title
Mitotic Stress Is an Integral Part of the Oncogene-Induced Senescence Program that Promotes Multinucleation and Cell Cycle Arrest.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 18 Downloadable Samples
Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Pulmonary hypertension (PH) and cancer pathophysiology share common signal transduction pathways leading to abnormal endothelial and smooth muscle cell interactions and angioproliferative vasculopathy. Sorafenib (Sor) a drug in clinical trials for cancer treatment, is an inhibitor of multiple kinases important in angiogenesis (Raf-1 kinase, VEGFR-2, VEGFR-3, PDGFR-beta). In this study, we assessed the efficacy of Sor as a potential therapy for PH, and hypothesized that Sor prevents the development of both a conventional and an augmented rodent model of PH. We performed studies in Dahl Salt-Sensitive rats (SS) exposed to hypoxia alone and in combination with the VEGFR-2 inhibitor, SU5416, known to induce a well-characterized augmented PH phenotype. Rats were, thus, divided into 5 groups: normoxia/vehicle (Norm), hypoxia/vehicle (H), hypoxia/ SU5416 (H-SU), hypoxia/Sorafenib (H-Sor) and hypoxia/ SU5416/ Sorafenib (H-SU-Sor). Except for the Norm group, all rats were maintained in a hypoxia chamber with a FiO2 of 10%. Rats received a single injection of SU5416 on Day 1 (20 mg/kg) and Sor solution was administered daily by gavage (2.5mg/kg). After 3.5 weeks, all rats were assessed by open chest catheterizations for pulmonary vascular and right ventricular pressures. Lung and heart tissue were harvested for histological and microarray analyses. Our results showed H-SU rats developed severe PH with changes in hemodynamic and histologic parameters when compared to Norm controls while rats exposed to H alone only displayed mildly elevated pressures compared with Norm. There was no significant change in pressures in the H-Sor or H-SU-Sor compared to Norm. Histopathology demonstrated a dramatic prevention of the PH phenotype in the H-SU-Sor rats with no significant remodeling compared with H-SU rats. Expression profiling data from H (n=4) and H-SU (n=3) rat lungs were compared to Norm (n=4) using normalization in R and SAM (>.639,) (minimum fold change >1.4). With false discovery rates (FDR) of 6.5% in hypoxia and 1.6% in H-SU, 1019 and 465 genes, respectively, were differentially-regulated compared to Norm. In addition, 38 genes were differentially expressed between H-SU and H-SU-Sor (n=4, FDR 6.7%) revealing a molecular signature with potentially novel target genes of Sor. Five differentially expressed genes (Tgfbeta3, C1qg, Nexn, Frzb, and Plaur) were examined by real-time RT-PCR and three were further validated by immunohistochemistry confirming the regulation on protein level. Based on the known pathways of hypoxic-induced PH and Sor, we further utilized immunohistochemistry to show the up-regulation of mediators of the MAPK cascade in the H and H-SU models of PH with subsequent, down-regulation by Sor. We therefore present Sor as a novel treatment for the development of severe PH and theorize that the MAPK cascade is a canonical pathway involved both in the development of PH and in the attenuation by Sor.
Publication Title
Genomic assessment of a multikinase inhibitor, sorafenib, in a rodent model of pulmonary hypertension.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 11 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Pulmonary hypertension (PH) and cancer pathophysiology share common signal transduction pathways leading to abnormal endothelial and smooth muscle cell interactions and angioproliferative vasculopathy. Sorafenib (Sor) a drug in clinical trials for cancer treatment, is an inhibitor of multiple kinases important in angiogenesis (Raf-1 kinase, VEGFR-2, VEGFR-3, PDGFR-beta). In this study, we assessed the efficacy of Sor as a potential therapy for PH, and hypothesized that Sor prevents the development of both a conventional and an augmented rodent model of PH. We performed studies in Dahl Salt-Sensitive rats (SS) exposed to hypoxia alone and in combination with the VEGFR-2 inhibitor, SU5416, known to induce a well-characterized augmented PH phenotype. Rats were, thus, divided into 5 groups: normoxia/vehicle (Norm), hypoxia/vehicle (H), hypoxia/ SU5416 (H-SU), hypoxia/Sorafenib (H-Sor) and hypoxia/ SU5416/ Sorafenib (H-SU-Sor). Except for the Norm group, all rats were maintained in a hypoxia chamber with a FiO2 of 10%. Rats received a single injection of SU5416 on Day 1 (20 mg/kg) and Sor solution was administered daily by gavage (2.5mg/kg). After 3.5 weeks, all rats were assessed by open chest catheterizations for pulmonary vascular and right ventricular pressures. Lung and heart tissue were harvested for histological and microarray analyses. Our results showed H-SU rats developed severe PH with changes in hemodynamic and histologic parameters when compared to Norm controls while rats exposed to H alone only displayed mildly elevated pressures compared with Norm. There was no significant change in pressures in the H-Sor or H-SU-Sor compared to Norm. Histopathology demonstrated a dramatic prevention of the PH phenotype in the H-SU-Sor rats with no significant remodeling compared with H-SU rats. Expression profiling data from H (n=4) and H-SU (n=3) rat lungs were compared to Norm (n=4) using normalization in R and SAM (>.639,) (minimum fold change >1.4). With false discovery rates (FDR) of 6.5% in hypoxia and 1.6% in H-SU, 1019 and 465 genes, respectively, were differentially-regulated compared to Norm. In addition, 38 genes were differentially expressed between H-SU and H-SU-Sor (n=4, FDR 6.7%) revealing a molecular signature with potentially novel target genes of Sor. Five differentially expressed genes (Tgfbeta3, C1qg, Nexn, Frzb, and Plaur) were examined by real-time RT-PCR and three were further validated by immunohistochemistry confirming the regulation on protein level. Based on the known pathways of hypoxic-induced PH and Sor, we further utilized immunohistochemistry to show the up-regulation of mediators of the MAPK cascade in the H and H-SU models of PH with subsequent, down-regulation by Sor. We therefore present Sor as a novel treatment for the development of severe PH and theorize that the MAPK cascade is a canonical pathway involved both in the development of PH and in the attenuation by Sor.
Publication Title
Genomic assessment of a multikinase inhibitor, sorafenib, in a rodent model of pulmonary hypertension.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 7 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Pulmonary hypertension (PH) and cancer pathophysiology share common signal transduction pathways leading to abnormal endothelial and smooth muscle cell interactions and angioproliferative vasculopathy. Sorafenib (Sor) a drug in clinical trials for cancer treatment, is an inhibitor of multiple kinases important in angiogenesis (Raf-1 kinase, VEGFR-2, VEGFR-3, PDGFR-beta). In this study, we assessed the efficacy of Sor as a potential therapy for PH, and hypothesized that Sor prevents the development of both a conventional and an augmented rodent model of PH. We performed studies in Dahl Salt-Sensitive rats (SS) exposed to hypoxia alone and in combination with the VEGFR-2 inhibitor, SU5416, known to induce a well-characterized augmented PH phenotype. Rats were, thus, divided into 5 groups: normoxia/vehicle (Norm), hypoxia/vehicle (H), hypoxia/ SU5416 (H-SU), hypoxia/Sorafenib (H-Sor) and hypoxia/ SU5416/ Sorafenib (H-SU-Sor). Except for the Norm group, all rats were maintained in a hypoxia chamber with a FiO2 of 10%. Rats received a single injection of SU5416 on Day 1 (20 mg/kg) and Sor solution was administered daily by gavage (2.5mg/kg). After 3.5 weeks, all rats were assessed by open chest catheterizations for pulmonary vascular and right ventricular pressures. Lung and heart tissue were harvested for histological and microarray analyses. Our results showed H-SU rats developed severe PH with changes in hemodynamic and histologic parameters when compared to Norm controls while rats exposed to H alone only displayed mildly elevated pressures compared with Norm. There was no significant change in pressures in the H-Sor or H-SU-Sor compared to Norm. Histopathology demonstrated a dramatic prevention of the PH phenotype in the H-SU-Sor rats with no significant remodeling compared with H-SU rats. Expression profiling data from H (n=4) and H-SU (n=3) rat lungs were compared to Norm (n=4) using normalization in R and SAM (>.639,) (minimum fold change >1.4). With false discovery rates (FDR) of 6.5% in hypoxia and 1.6% in H-SU, 1019 and 465 genes, respectively, were differentially-regulated compared to Norm. In addition, 38 genes were differentially expressed between H-SU and H-SU-Sor (n=4, FDR 6.7%) revealing a molecular signature with potentially novel target genes of Sor. Five differentially expressed genes (Tgfbeta3, C1qg, Nexn, Frzb, and Plaur) were examined by real-time RT-PCR and three were further validated by immunohistochemistry confirming the regulation on protein level. Based on the known pathways of hypoxic-induced PH and Sor, we further utilized immunohistochemistry to show the up-regulation of mediators of the MAPK cascade in the H and H-SU models of PH with subsequent, down-regulation by Sor. We therefore present Sor as a novel treatment for the development of severe PH and theorize that the MAPK cascade is a canonical pathway involved both in the development of PH and in the attenuation by Sor.
Publication Title
Genomic assessment of a multikinase inhibitor, sorafenib, in a rodent model of pulmonary hypertension.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Illumina HiSeq 2000
Description
The ability to generate defined null mutations in mice revolutionized the analysis of gene function in mammals. However, gene-deficient mice generated by using 129-derived embryonic stem (ES) cells may carry large segments of 129 DNA, even when extensively backcrossed to reference strains, such as C57BL/6J, and this may confound interpretation of experiments performed in these mice. Tissue plasminogen activator (tPA), encoded by the PLAT gene, is a fibrinolytic serine protease that is widely expressed in the brain. A large number of neurological abnormalities have been reported in tPA-deficient mice. The studies here compare genes differentially expressed in the brains of Plat-/- mice from two independent Plat-/- mouse derivations to wild-type C57BL/6J mice. One strain denoted “Old” was constructed in ES cells from a 129 mouse and backcrossed extensively to C57BL/6J, and one denoted “New” Plat-/- mouse was constructed using zinc finger nucleases directly in the C57BL/6J-Plat-/- mouse strain. We identify a significant set of genes that are differentially expressed in the brains of Old Plat-/- mice that preferentially cluster in the vicinity of Plat on chromosome 8, apparently linked to more than 20 Mbp of DNA flanking Plat being of 129 origin. No such clustering is seen in the New Plat-/- mice. Overall design: Whole-transcriptome profiling of the cerebral cortex of wild-type control C57BL/6J mice and two independent Plat-/- mice strains on the C57BL/6J background.
Publication Title
Passenger mutations and aberrant gene expression in congenic tissue plasminogen activator-deficient mouse strains.
Sample Metadata Fields
Age, Specimen part, Cell line, Subject
View Samples
GSE2368- Mus musculus, Rattus norvegicus
- 8 Downloadable Samples
- Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
This series contain mouse and rat lung samples treated with mechanical ventilation and corresponded controls.
Publication Title
Bioinformatic identification of novel early stress response genes in rodent models of lung injury.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 18 Downloadable Samples
- Affymetrix Yeast Genome S98 Array (ygs98)
Description
We are investigating the transcriptional response of yeast to treatment with enediynes or gamma radiation, which generate different extents of double or single strand breaks in DNA.
Publication Title
The DNA-damage signature in Saccharomyces cerevisiae is associated with single-strand breaks in DNA.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 12 Downloadable Samples
- Affymetrix Yeast Genome S98 Array (ygs98)
Description
We are investigating the transcriptional response of Anc1 deficient yeast under basal and MMS exposed conditions
Publication Title
Anc1, a protein associated with multiple transcription complexes, is involved in postreplication repair pathway in S. cerevisiae.
Sample Metadata Fields
No sample metadata fields
View Samples