Project description:Two molecular subtypes of pancreatic ductal adenocarcinoma (PDAC) have been proposed: the “Classical” and “Basal-like” subtypes. However, the “molecular” classification has not been applied in real-world clinical practice. This study aimed to establish patient-derived organoids (PDOs) for PDAC and evaluate their application in subtype classification and clinical outcome prediction. We constructed a PDO library for morphologic and RNA-seq analyses and drug response assays in vitro. PDOs of PDAC were established at a high efficiency (> 70%) with at least 100,000 live cells. Morphologically, PDOs were classified as gland-like structures (GL type) or densely proliferating inside (DP type). RNA-seq analysis revealed that the “morphological” subtype (GL vs. DP) roughly corresponded to the “molecular” subtype (“Classical” vs. “Basal-like”). The proposed “morphological” classification predicted clinical treatment response and prognosis; the median overall survival of patients with GL type were significantly longer than that of those with DP type (P < 0.005). The GL type showed a better response to gemcitabine than the DP type in vitro, whereas the drug response of the DP type was improved by the combination of ERK and autophagy inhibition. PDAC PDOs facilitated subtype determination and clinical outcome prediction, thereby advancing precision medicine for PDAC.
Project description:Our study focuses on understanding the genomic occupancy profile of Rbf and Dp in flight muscles of D. melanogaster. We analyzed Rbf and Dp occupancy by ChIP-seq using Rbf and Dp antibodies in dissected flight muscles of pharate flies (WT)
Project description:We performed ChIP-Seq for hallmark TFs (Ets1, Runx1), histone modification marks (H3K4me1, H3K4me2, H3K4me3, H3K27me3, H3K36me3), total RNA Pol II, short RNA-Seq as well as nucleosome mapping mainly in murine Rag2 -/- thymocytes. We also performed ChIP-Seq for E47 as well as nucleosome mapping, gene expression microarray analysis in CD4+ CD8+ DP thymocytes. Overall, we find a key role for the transcription factor Ets1, contributing towards alpha beta T cell lineage commitment via differential transactivation of stage-specific genes orchestrated by dynamic, co-association -mediated chromatin remodeling, as well as transcription dependent generation of a specialized chromatin structure at the TCR beta locus. Genome-wide analysis via ChIP-Seq for Ets1, Runx1, total RNA Pol II binding, H3K4me1, H3K4me2, H3K4me3, H3K27me3, H3K36me3, short RNA-Seq, Mnase-Seq in murine Rag2 -/- thymocytes, ChIP-Seq for E47, Mnase-Seq and gene expression microarray analysis in DP thymocytes This Series represents ChIP-Seq data.
Project description:Transforming growth factor (TGF) plays an important role in tooth morphogenesis and mineralization. During postnatal development, the dental pulp (DP) mesenchyme secretes neurotrophic factors that guide trigeminal nerve fibers into and throughout the DP. This process is tightly linked with dentin formation and mineralization. Our laboratory established a mouse model in which Tgfbr2 was conditionally deleted in DP mesenchyme using an Osterix promoter-driven Cre recombinase (Tgfbr2cko). These mice survived postnatally with significant defects in bones and teeth, including reduced mineralization and short roots. Hematoxylin and eosin staining revealed reduced axon-like structures in the mutant mice. Reporter imaging demonstrated that Osterix-Cre activity within the tooth was active in the DP and derivatives, but not in neurons. Immunofluorescence staining for 3 tubulin (neuronal marker) was performed on serial cryosections from control and mutant molars on postnatal days 7 and 24 (P7, P24). Confocal imaging and pixel quantification demonstrated reduced innervation in Tgfbr2cko first molars at both stages compared to controls, indicating that signals necessary to promote neurite outgrowth were disrupted by Tgfbr2 deletion. We performed mRNA-Sequence (RNA-Seq) and gene onotology analyses using RNA from the DP of P7 control and mutant mice to investigate the pathways involved in Tgfbr2-mediated tooth development. These analyses identified downregulation of several mineralization-related and neuronal genes in the Tgfbr2cko DP compared to controls. Select gene expression patterns were confirmed by quantitative real-time PCR and immunofluorescence imaging. Lastly, trigeminal neurons were co-cultured atop Transwell filters overlying primary Tgfbr2f/f DP cells. Tgfbr2 in the DP was deleted via adenovirus-expressed Cre recombinase. Confocal imaging of axons through the filter pores showed increased axonal sprouting from neurons cultured with Tgfbr2-positive DP cells compared to neurons cultured alone. Axon sprouting was reduced when Tgfbr2 was knocked down in the DP cells. Immunofluorescence of dentin sialophosphoprotein in co-cultured DP cells confirmed reduced mineralization potential in cells with Tgfbr2 deletion. Both our proteomics and RNA-Seq analyses indicate that axonal guidance cues, particularly semaphorin signaling, were disrupted by Tgfbr2 deletion. Thus, Tgfbr2 in the DP mesenchyme appears to regulate differentiation and the cells’ ability to guide neurite outgrowth during tooth mineralization and innervation.
Project description:We performed ChIP-Seq for hallmark TFs (Ets1, Runx1), histone modification marks (H3K4me1, H3K4me2, H3K4me3, H3K27me3, H3K36me3), total RNA Pol II, short RNA-Seq as well as nucleosome mapping mainly in murine Rag2 -/- thymocytes. We also performed ChIP-Seq for E47 as well as nucleosome mapping, gene expression microarray analysis in CD4+ CD8+ DP thymocytes. Overall, we find a key role for the transcription factor Ets1, contributing towards alpha beta T cell lineage commitment via differential transactivation of stage-specific genes orchestrated by dynamic, co-association -mediated chromatin remodeling, as well as transcription dependent generation of a specialized chromatin structure at the TCR beta locus. Genome-wide analysis via ChIP-Seq for Ets1, Runx1, total RNA Pol II binding, H3K4me1, H3K4me2, H3K4me3, H3K27me3, H3K36me3, short RNA-Seq, Mnase-Seq in murine Rag2 -/- thymocytes, ChIP-Seq for E47, Mnase-Seq and gene expression microarray analysis in DP thymocytes This Series represents Mnase-Seq data.
Project description:H3K27Ac ChIP-seq in wild type and cohesin-deficient thymocytes Rad21 was deleted in CD4+ CD8+ double positive (DP) thymocytes by crossing a Rad21 floxed allele with a Cd4-driven Cre transgene. DP positive thymocytes were FACS-sorted from control and Rad21-/- littermates, which were then used to perform chromatin immunoprecipitation for histone H3 acetylated on lysine 27 (H3K27Ac).
Project description:Pancreatic adenocarcinoma (PDAC) is one of the most lethal human malignancies and a major health problem. Patient-derived tumor xenografts (PDTXs) have been increasingly used as a prime approach for preclinical studies despite being insufficiently characterized as a model of the human disease and its diversity. Extensive multiomics characterization of these PDTXs have demonstrated their utility as a suitable model for preclinical studies, representing the diversity of the primary cancers. We performed a multi-factorial integrative analysis of genome-wide ChIP-seq on multiple histone modifications, as well as RNA-seq on subcutaneous PDTXs from 24 PDAC samples obtained either surgically or using diagnostic biopsies (endoscopic ultrasound guided fine needle aspirate). In the dataset, ChIP-seq for five distinct histone marks (H3K4me1, H3K27ac, H3K4me3, H3K27me3, and H3K9me3) and RNA-seq was carried out to generate new knowledge on the epigenetic landscapes underlying the heterogeneity of PDAC tissues grown in this manner.
Project description:Chromatin remodeling proteins are frequently dysregulated in human cancer, yet little is known about how they control tumorigenesis. Here, we uncover an epigenetic program mediated by the NAD+-dependent histone deacetylase Sirtuin 6 (SIRT6) that is critical for suppression of pancreatic ductal adenocarcinoma (PDAC), one of the most lethal malignancies. SIRT6 inactivation accelerates PDAC progression and metastasis via upregulation of Lin28b, a negative regulator of the let-7 microRNA. SIRT6 loss results in histone hyperacetylation at the Lin28b promoter, Myc recruitment, and pronounced induction of Lin28b and downstream let-7 target genes, HMGA2, IGF2BP1 and IGF2BP3. This epigenetic program defines a distinct subset representing 30-40% of human PDAC, characterized by poor prognosis and an exquisite dependence on Lin28b for tumor growth. Thus, we identify SIRT6 as an important PDAC tumor suppressor, and uncover the Lin28b pathway as a potential therapeutic target in a molecularlydefined PDAC subset. ChIP-Seq experiments to examine H3K56ac histone modifications in murine PDAC cells that are Sirt6 wild type (WT), Sirt6 knock-out (KO), and Sirt6 KO cells engineered to express Sirt6 WT (Sirt6 KO + Sirt6 WT Restored).