Project description:To investigate the relation of small intestine neuroendocrine tumor (SI-NET) properties and epigenetics to normal human enteroendocrine cell differentiation [scATAC-seq] We established Neurog3ER inducible cell lines and then performed chromatin analysis at single cell level using data obtained from normal EEC single cell ATAC-seq at various time points.
Project description:Part I - SI-NET tumors High Resolution Isoelectric Focusing (HiRIEF) LC-MS and relative quantification by iTRAQ 8-plex was used to analyze 14 small intestinal neuroendocrine tumors (SI-NETs). The data was obtained from two separate TMT10plex sets and linked by a single internal pooled standard. The internal pooled standard was made by combining equal aliquots of the tryptic peptide mixtures from each of the 14 tissue samples. iTRAQ set1 was composed of 7 SI-NET samples, all from different individuals, and internal pooled standard labelled as follows: Channel 113 (sample Screen-1 with liver metastasis), Channel 114 (sample Screen-8 with liver metastasis), Channel 115 (sample Screen-3 with liver metastasis), Channel 116 (sample Screen-2 with liver metastasis), Channel 117 (sample Screen-5 no liver metastasis), Channel 118 (sample Screen-4 no liver metastasis), Channel 119 (sample Screen-10 no liver metastasis), Channel 121 (internal pooled standard). iTRAQ set2 was composed of 7 SI-NET samples, all from different individuals, and internal pooled standard labelled as follows: Channel 113 (sample Screen-7 with liver metastasis), Channel 114 (sample Screen-11 with liver metastasis), Channel 115 (sample Screen-13 with liver metastasis), Channel 116 (sample Screen-6 no liver metastasis), Channel 117 (sample Screen-12 no liver metastasis), Channel 118 (sample Screen-9 no liver metastasis), Channel 119 (sample Screen-14 no liver metastasis), Channel 121 (internal pooled standard). Part II - time course profiling in cell lines High Resolution Isoelectric Focusing (HiRIEF) LC-MS and relative quantification by TMT 10-plex was used to analyze cellular response to the neddylation inhibitor pevonedistat (MLN4924) at different timepoints in two SI-NET (small intestinal neuroendocrine tumors) cell lines. The data was obtained from two separate TMT 10-plex experiments. TMT set1 includes a time course experiment upon pevonedistat treatment of CNDT2 cells with harvests at 2h, 6h, 12h and 24h after treatment as well as of untreated control cells. Isobaric tag labelling of peptide samples with TMT10plex was used as follows. Biological duplicate controls (TMT channels 126, 127N), duplicate 2h (127C, 128N), duplicate 6h (128C, 129N), duplicate 12h (129C, 130N) and duplicate 24h (130C, 131) samples were employed. TMT set2 includes a time course experiment upon pevonedistat treatment of HC45 cells with harvests at 2h, 6h, 12h and 24h after treatment as well as of untreated control cells. Isobaric tag labelling of peptide samples with TMT10plex was used as follows. Biological duplicate controls (TMT channels 126, 127N), duplicate 2h (127C, 128N), duplicate 6h (128C, 129N), duplicate 12h (129C, 130N) and duplicate 24h (130C, 131) samples were employed.
Project description:Associated to PXD009877 which contains Part I and Part II. Part III – Pevonedistat/MLN4924 and Bortezomib treatment of the SI-NET (small intestinal – neuroendocrine tumor) cell line CNDT2. High Resolution Isoelectric Focusing (HiRIEF) LC-MS and relative quantification by TMT 10-plex was used to analyze cellular response to the proteasome inhibitor Bortezomib alone or in combination with the neddylation inhibitor pevonedistat (MLN4924) at 12h after treatment in the CNDT2 cell line. The data was obtained from one TMT 10-plex experiment which included 4 untreated controls (TMT channels 126, 127N, 127C and 128N), 3 samples treated with 500 nM Bortezomib for 12 hours (TMT channels 128C, 129N and 129C) as well as 3 samples treated with both Bortezomib and Pevonedistat at 500 nM respectively for 12 hours (TMT channels 130N, 130C and 131).
Project description:Expression profile of human GEP-NET tumors, including 113 fresh frozen biopsies of primary and metastatic tumours originating from pancreas (P-NET, 83 primary and 30 metastasis), 81 from small intestine (SI-NET, 44 primary and 37 metastasis), and 18 from rectum (RE-NET, 3 primary and 15 metastasis).
Project description:Mutationally silent small intestinal neuroendocrine tumors (SI-NETs) characterized by few recurrent alterations, such as those that inactivate the cyclin-dependent kinase (CDK) inhibitor CDKN1B in <10% of cases are not well defined at the molecular level. Since the native enteroendocrine cells (EECs), which these tumors resemble, are scarce; the lack of reference data from normal EECs limits identification of gene and cis-element dysregulation in SI-NETs. We established transcriptional landscapes (RNA-seq) in bulk cultures and at single-cell (sc) resolution during the trajectory of normal human EEC differentiation from ileal stem cells in vitro (PMID 38733993). We compared the findings in SI-NETs against the novel reference profiles of normal human EEC differentiation and maturation. SI-NETs correspond principally to mature EC cells, with discernible features of non-EC and progenitor cells; persistent expression of the latter genes likely contributes to malignant properties. Underlying this aberrant expression pattern we found diverse SI-NET enhancers. EECs normally differentiate through an intermediate HES6hi/ASCL1+ oscillatory state before NEUROD1+ pre-terminal cells emerge; ASCL1 expression then persists only in mature EC cells. In contrast, although SI-NETs express NEUROD1, they strictly lack ASCL1 and other genes normally co-expressed with ASCL1. Notably, ASCL1 and loci encoding transcription factors that define non-EC cell types (ISL1, ARX, PAX6, PDX1) are marked with H3K27me3, signifying epigenetic silencing. SI-NETs express CDKN1B but other CDK inhibitors, e.g., CDKN2A and CDKN1C, are epigenetically silenced, suggesting that tumor cells may especially depend on wild-type CDKN1B function. Chromatin and transcriptional features of SI-NETs, revealed for the first time with respect to normal EEC differentiation, will help identify tumorigenic pathways and candidate therapeutic targets.
Project description:Mutationally silent small intestinal neuroendocrine tumors (SI-NETs) characterized by few recurrent alterations, such as those that inactivate the cyclin-dependent kinase (CDK) inhibitor CDKN1B in <10% of cases are not well defined at the molecular level. Since the native enteroendocrine cells (EECs), which these tumors resemble, are scarce; the lack of reference data from normal EECs limits identification of gene and cis-element dysregulation in SI-NETs. We established transcriptional landscapes (RNA-seq) in bulk cultures and at single-cell (sc) resolution during the trajectory of normal human EEC differentiation from ileal stem cells in vitro (PMID 38733993). We compared the findings in SI-NETs against the novel reference profiles of normal human EEC differentiation and maturation. SI-NETs correspond principally to mature EC cells, with discernible features of non-EC and progenitor cells; persistent expression of the latter genes likely contributes to malignant properties. Underlying this aberrant expression pattern we found diverse SI-NET enhancers. EECs normally differentiate through an intermediate HES6hi/ASCL1+ oscillatory state before NEUROD1+ pre-terminal cells emerge; ASCL1 expression then persists only in mature EC cells. In contrast, although SI-NETs express NEUROD1, they strictly lack ASCL1 and other genes normally co-expressed with ASCL1. Notably, ASCL1 and loci encoding transcription factors that define non-EC cell types (ISL1, ARX, PAX6, PDX1) are marked with H3K27me3, signifying epigenetic silencing. SI-NETs express CDKN1B but other CDK inhibitors, e.g., CDKN2A and CDKN1C, are epigenetically silenced, suggesting that tumor cells may especially depend on wild-type CDKN1B function. Chromatin and transcriptional features of SI-NETs, revealed for the first time with respect to normal EEC differentiation, will help identify tumorigenic pathways and candidate therapeutic targets.
Project description:Mutationally silent small intestinal neuroendocrine tumors (SI-NETs) characterized by few recurrent alterations, such as those that inactivate the cyclin-dependent kinase (CDK) inhibitor CDKN1B in <10% of cases are not well defined at the molecular level. Since the native enteroendocrine cells (EECs), which these tumors resemble, are scarce; the lack of reference data from normal EECs limits identification of gene and cis-element dysregulation in SI-NETs. We established transcriptional landscapes (RNA-seq) in bulk cultures and at single-cell (sc) resolution during the trajectory of normal human EEC differentiation from ileal stem cells in vitro (PMID 38733993). We compared the findings in SI-NETs against the novel reference profiles of normal human EEC differentiation and maturation. SI-NETs correspond principally to mature EC cells, with discernible features of non-EC and progenitor cells; persistent expression of the latter genes likely contributes to malignant properties. Underlying this aberrant expression pattern we found diverse SI-NET enhancers. EECs normally differentiate through an intermediate HES6hi/ASCL1+ oscillatory state before NEUROD1+ pre-terminal cells emerge; ASCL1 expression then persists only in mature EC cells. In contrast, although SI-NETs express NEUROD1, they strictly lack ASCL1 and other genes normally co-expressed with ASCL1. Notably, ASCL1 and loci encoding transcription factors that define non-EC cell types (ISL1, ARX, PAX6, PDX1) are marked with H3K27me3, signifying epigenetic silencing. SI-NETs express CDKN1B but other CDK inhibitors, e.g., CDKN2A and CDKN1C, are epigenetically silenced, suggesting that tumor cells may especially depend on wild-type CDKN1B function. Chromatin and transcriptional features of SI-NETs, revealed for the first time with respect to normal EEC differentiation, will help identify tumorigenic pathways and candidate therapeutic targets.
Project description:I investigated the role of insulin receptor substrate 2 (IRS2) in small-intestinal neuroendocrine tumours (SI-NETs). Using SI-NET cell lines (STC-1 and Glu-tag), I found that IRS2 was significantly upregulated. IRS2 knockdown inhibited cellular proliferation, migration, and invasion, while its overexpression promoted these processes. For in vivo validation, I established stable IRS2-knockdown cell lines and performed xenograft experiments in nude mice. Transcriptomic profiling by RNA sequencing was conducted to identify downstream targets of IRS2 signaling.
Project description:Enteroendocrine cells (EECs) are hormone-producing cells residing in the epithelium of stomach, small intestine (SI) and colon. EECs regulate various aspects of metabolic activity including insulin levels, satiety, gastrointestinal secretion and motility. The generation of different EEC lineages of the SI is incompletely understood. We now report a TFome-wide CRISPR knockout screen in adult human intestinal organoids to identify dominant transcription factors controlling EEC differentiation. ZNF800 is discovered as a master repressor for endocrine lineage commitment, which particularly restricts enterochromaffin cell differentiation by directly controlling an endocrine TF network centered on PAX4. Thus, organoid models allow unbiased functional SCRISPR screens for genes that program cell differentiation.
Project description:Enteroendocrine cells (EECs) are hormone-producing cells residing in the epithelium of stomach, small intestine (SI) and colon. EECs regulate various aspects of metabolic activity including insulin levels, satiety, gastrointestinal secretion and motility. The generation of different EEC lineages of the SI is incompletely understood. We now report a TFome-wide CRISPR knockout screen in adult human intestinal organoids to identify dominant transcription factors controlling EEC differentiation. ZNF800 is discovered as a master repressor for endocrine lineage commitment, which particularly restricts enterochromaffin cell differentiation by directly controlling an endocrine TF network centered on PAX4. Thus, organoid models allow unbiased functional SCRISPR screens for genes that program cell differentiation.