Project description:Mammalian genomes contain several billion base pairs of DNA which are packaged in chromatin fibers. At selected gene loci, cohesin complexes have been proposed to arrange chromatin fibers into higher-order structures, but it is poorly understood how cohesin performs this task, how important this function is for determining the structure of chromosomes, and how this process is regulated to allow changes in gene expression. Here we show that the cohesin release factor Wapl controls chromatin structure and gene regulation at numerous loci throughout the mouse genome. Conditional deletion of the Wapl gene leads to stable accumulation of cohesin on chromatin, chromatin compaction, altered gene expression, cell cycle delay, chromosome segregation defects and embryonic lethality. In Wapl deficient chromosomes, cohesin accumulates in an axial domain, similar to how condensins form a M-bM-^@M-^\scaffoldM-bM-^@M-^] in mitotic chromosomes. We propose that Wapl controls chromatin structure and gene regulation by determining the residence time with which cohesin binds to DNA. 4 biological replicates for each genotype (Wapl +/F; Wapl -/F) treated with/without 4-OHT =16 samples
Project description:RNA of control mouse mammary epithelial cells (EpH4 control) and corresponding fra1 overexpressing cells (EpH4fra1 cl1 and EpH4fra1 cl2) was hybridized onto an 53MM chip and differentially expressed targets were further analysed. For each sample hybridization was performed in technical triplicate By comparison of the gene expression profiles of these samples, genes with significantly altered expression levels will be selected and further characterized.
Project description:Liver carcinogenesis induced by DEN closely mimics the pathologies observed during human liver tumor initiation and progression. DEN treatment triggered c-Jun expression lasting up to at least 1 week in mouse livers as measured by Western blots and immunohistochemical staining. DEN-induced liver tumorigenesis was also dramatically reduced in Alfp-cre+/c-jun f/f mice, in which c-Jun is constitutively deleted in hepatocytes around birth. These data unambiguously demonstrate that c-Jun is specifically required during liver cancer initiation. We searched for cell death effectors downstream of c-Jun operating in cancer initiation. Expression profiling revealed that several cell death-associated genes were deregulated by comparing Alfp-cre+/c-junf/f and Alfp-cre-/c-jun f/f livers. Mouse livers were collected before and 48hours after diethylnitrosamine treament (100mg/kg body weight). Whole genome expression profiles were analyzed using total RNAs extracted from the whole liver samples. By comparison of the gene expression profiles of these samples, genes with significantly altered expression levels will be selected and further characterized for their roles in DEN-induce liver cell death in tumor initiation.
Project description:Liver carcinogenesis induced by DEN closely mimics the pathologies observed during human liver tumor initiation and progression. DEN treatment triggered c-Jun expression lasting up to at least 1 week in mouse livers as measured by Western blots and immunohistochemical staining. DEN-induced liver tumorigenesis was also dramatically reduced in Alfp-cre+/c-jun f/f mice, in which c-Jun is constitutively deleted in hepatocytes around birth. These data unambiguously demonstrate that c-Jun is specifically required during liver cancer initiation. We searched for cell death effectors downstream of c-Jun operating in cancer initiation. Expression profiling revealed that several cell death-associated genes were deregulated by comparing Alfp-cre+/c-junf/f and Alfp-cre-/c-jun f/f livers. Mouse livers were collected before and 48hours after diethylnitrosamine treament (100mg/kg body weight). Whole genome expression profiles were analyzed using total RNAs extracted from the whole liver samples. By comparison of the gene expression profiles of these samples, genes with significantly altered expression levels will be selected and further characterized for their roles in DEN-induce liver cell death in tumor initiation.
Project description:Liver carcinogenesis induced by DEN closely mimics the pathologies observed during human liver tumor initiation and progression. DEN treatment triggered c-Jun expression lasting up to at least 1 week in mouse livers as measured by Western blots and immunohistochemical staining. DEN-induced liver tumorigenesis was also dramatically reduced in Alfp-cre+/c-jun f/f mice, in which c-Jun is constitutively deleted in hepatocytes around birth. These data unambiguously demonstrate that c-Jun is specifically required during liver cancer initiation. We searched for cell death effectors downstream of c-Jun operating in cancer initiation. Expression profiling revealed that several cell death-associated genes were deregulated by comparing Alfp-cre+/c-junf/f and Alfp-cre-/c-jun f/f livers. Mouse livers were collected before and 48hours after diethylnitrosamine treament (100mg/kg body weight). Whole genome expression profiles were analyzed using total RNAs extracted from the whole liver samples. By comparison of the gene expression profiles of these samples, genes with significantly altered expression levels will be selected and further characterized for their roles in DEN-induce liver cell death in tumor initiation.
Project description:This SuperSeries is composed of the following subset Series: GSE39928: Murine livers post DEN treatment: c-Jun f/f vs. c-Jun Dli [35MM] GSE39929: Murine livers post DEN treatment: c-Jun f/f vs. c-Jun Dli [40MM] GSE39930: Murine livers post DEN treatment: c-Jun f/f vs. c-Jun Dli [41MM] GSE39931: Murine livers post DEN treatment: c-Jun f/f vs. c-Jun Dli [43MM] Refer to individual Series ** Six samples in each Series represent the same set of biological source material hybridized to 4 different arrays (named IMP internal: 35MM, 40MM, 41MM, and 43MM).
Project description:Liver carcinogenesis induced by DEN closely mimics the pathologies observed during human liver tumor initiation and progression. DEN treatment triggered c-Jun expression lasting up to at least 1 week in mouse livers as measured by Western blots and immunohistochemical staining. DEN-induced liver tumorigenesis was also dramatically reduced in Alfp-cre+/c-jun f/f mice, in which c-Jun is constitutively deleted in hepatocytes around birth. These data unambiguously demonstrate that c-Jun is specifically required during liver cancer initiation. We searched for cell death effectors downstream of c-Jun operating in cancer initiation. Expression profiling revealed that several cell death-associated genes were deregulated by comparing Alfp-cre+/c-junf/f and Alfp-cre-/c-jun f/f livers. Mouse livers were collected before and 48hours after diethylnitrosamine treament (100mg/kg body weight). Whole genome expression profiles were analyzed using total RNAs extracted from the whole liver samples. By comparison of the gene expression profiles of these samples, genes with significantly altered expression levels will be selected and further characterized for their roles in DEN-induce liver cell death in tumor initiation.
Project description:Transcriptional profiling of control and MKK7-deficient primary mouse pneumocytes after oncogenic KRasG12 induction Two-condition experiment, MKK7 proficient vs. MKK7 deficient pneumocytes. 3 Biological replicates: 3 control, 3 knock out, independently grown and harvested. 3 technical replicates per array (each sample was hybridized to 3 in-house arrays (47MM, 51MM and 46MM - see HybridisationInfo.xls) for a total of 54 hybridizations).
Project description:DNA methylation plays a significant role in assuring cell identity, thus potentiating its application in molecular classification of cancers in respect of tissue origins or clinically and aetiologically distinct subtypes. In this study, we adapted our liquid hybridization capture-based bisulfite sequencing approach on the targeted sequencing of promoter methylomes. We detected ten cell lines originated from different tissue origins and demonstrated a similar potentiality of promoter methylomes as classifiers for cancer cell lines from different tissue origins in comparison with gene expression profiles. Furthermore, promoter methylome can sensitively differentiate two different cell lines from the same tissue origin in respect of the CpG island methylator phenotype (CIMP), as in the case of AGS and BGC-823 gastric cancer cell lines. These results potentiate the targeted sequencing of promoter methylomes as a means for comprehensive screening and classifying cancer cells with respect to tissue-origins and CIMP subtypes in the future studies. We proved the potentiality of promoter-targeted LHC-BS that requires reduced experimental cost and less amount of initial DNA samples in comparison with a previous design [23] using YH cell line. In addition, we generated single-base promoter methylomes for ten cell lines, including eight cancer cell lines generated from four types of tissues and one pair of model cell lines for ovarian cancer (T29 and T29H). We proved the potentiality of promoter-targeted LHC-BS that requires reduced experimental cost and less amount of initial DNA samples in comparison with a previous design using YH cell line. In addition, we generated single-base promoter methylomes for ten cell lines, including eight cancer cell lines generated from four types of tissues and one pair of model cell lines for ovarian cancer (T29 and T29H).
Project description:Colorectal cancer (CRC) is a genetically heterogeneous disease with several distinct morphological growth patterns. This study was aimed to investigate genes differentially expressed between ulcerative and polypoid colorectal CRC. cDNA microarray was first employed to compare the gene expression profiling of ulcerative and polypoid CRC with paired normal mucosa. Potential candidates identified by data filtering were further validated using quantitative real-time polymerase chain reaction, western blot and immunohistochemistry. Epigenetic regulation of gene expression was investigated using methylation-specific PCR (MSP). cDNA microarray identified 11 up-regulated and 14 down-regulated genes differentially expressed in both types of tumor compared to matched normal mucosa. Among them, S100P was the only upregulated gene preferentially associated with polypoid CRC (p = 0.032), whereas no genes demonstrated significantly differential association with ulcerative CRC. S100P protein and mRNA expression level of polypoid CRC was significantly higher than that of ulcerative CRC (p < 0.05, respectively). Immunoreactivity of S100P protein was localized predominantly in the nuclei and to a less extent in the cytoplasm. Overexpression of S100P occurred early in the adenoma stage. 80% (24/30) and 20% (6/30) polypoid CRC showed diffusely strong and moderate overexpression, respectively. In contrast, S100P was diffusely and strongly expressed in 15% (6/40) ulcerative CRC, with 52.5% (21/40) and 32.5% (13/40) tumors having moderate and weak overexpression, respectively. S100P overexpression was preferentially associated with polypoid CRC (p < 0.001). The relative methylation level determined by MSP was not statistically different between polypoid and ulcerative CRC (43.36% vs. 49.10%, p = 0.168), indicating that promoter hypomethylation was directly related to upregulation of S100P mRNA. The gene expression profiling of ulcerative and polypoid CRC with paired normal mucosa were compared. Dye swapping experiments with ulcerative CRC vs normal mucosa or polypoid CRC vs normal mucosa were performed and we averaged the log ratios of the duplicated spots on each slide.