Project description:We present a new high-throughput sequencing-based technique, named Sequential Analysis of MacroMolecules accessibilitY (SAMMY-seq), for the genome-wide mapping of chromatin regions separated by differential accessibility. The method is based on the sequential extraction of multiple chromatin fractions, corresponding to increasingly compacted and less accessible chromatin regions, which are mapped along the genome using high-throughput sequencing. Using SAMMY-seq we analyzed Hutchinson-Gilford progeria syndrome (HGPS) skin fibroblasts and normal control fibroblasts. Additionally we carried out ChIP-seq for the H3K9me3 and H3K27me3 histone modifications and RNA-seq for the characterization of transcriptome changes on the same HGPS and control fibroblasts.
2020-09-05 | GSE118633 | GEO
Project description:HMGA1-mediated HGPS human skin fibroblasts Transcriptome
Project description:Analysis of BRD4 ChIP-seq data of two types of human transformed fibroblasts (WT and HGPS) to identify specific and common binding sites for BRD4. Transformed cell lines were obtained by retroviral introduction of TERT (T), V12-HRAS (R) and SV40 large and small T antigens (S) of primary skin fibroblasts for HGPS patients (TRS-HGPS) and age-matched control wild-type individuals (TRS-WT) Abstract: Advanced age and DNA damage accumulation are strong risk factors for cancer. The premature-aging disorder Hutchinson Gilford Progeria Syndrome (HGPS) provides a unique opportunity to study the interplay between DNA damage and aging-associated tumor mechanisms, since HGPS patients do not develop tumors despite elevated levels of DNA damage. Here, we have used HGPS patient cells to identify a protective mechanism to oncogenesis. We find that HGPS cells are resistant to neo-plastic transformation. This resistance is mediated by the bromodomain protein BRD4, which exhibits altered genome-wide binding patterns in transformation-resistant cells leading to inhibition of oncogenic de-differentiation. BRD4 also in-hibits, albeit to a lower extent, the tumorigenic potential of transformed cells from healthy individuals and BRD4-mediated tumor protection is clinically relevant, since a BRD4 gene signature predicts positive clinical outcome in breast and lung cancer. Our results demonstrate a protective function for BRD4 and suggest tissue-specific functions for BRD4 in tumorigenesis. Examination of BRD4 binding events in TRS-WT and TRS-HGPS fibroblasts (2 independent cell lines in each group)
Project description:Analysis of BRD4 ChIP-seq data of two types of human transformed fibroblasts (WT and HGPS) to identify specific and common binding sites for BRD4. Transformed cell lines were obtained by retroviral introduction of TERT (T), V12-HRAS (R) and SV40 large and small T antigens (S) of primary skin fibroblasts for HGPS patients (TRS-HGPS) and age-matched control wild-type individuals (TRS-WT) Abstract: Advanced age and DNA damage accumulation are strong risk factors for cancer. The premature-aging disorder Hutchinson Gilford Progeria Syndrome (HGPS) provides a unique opportunity to study the interplay between DNA damage and aging-associated tumor mechanisms, since HGPS patients do not develop tumors despite elevated levels of DNA damage. Here, we have used HGPS patient cells to identify a protective mechanism to oncogenesis. We find that HGPS cells are resistant to neo-plastic transformation. This resistance is mediated by the bromodomain protein BRD4, which exhibits altered genome-wide binding patterns in transformation-resistant cells leading to inhibition of oncogenic de-differentiation. BRD4 also in-hibits, albeit to a lower extent, the tumorigenic potential of transformed cells from healthy individuals and BRD4-mediated tumor protection is clinically relevant, since a BRD4 gene signature predicts positive clinical outcome in breast and lung cancer. Our results demonstrate a protective function for BRD4 and suggest tissue-specific functions for BRD4 in tumorigenesis.
Project description:We analyzed and compared global gene expression changes in fibroblasts from human subjects with HGPS compared to age matched controls. We then treated both control and HGPS fibroblasts with a protein farnesyltransferase inhibitor (FTI), a medication currently used in clinical trials to treat HGPS, to look for a reversal of the gene defects present in HGPS fibroblasts.
Project description:In this experiment, we aim to examine the role of NAT10 inhibition in Hutchinson-Gilford progeria syndrome (HGPS), a rare but devastating premature ageing syndrome caused by a mutation in the LMNA gene. NAT10 inhibition improves HGPS cellular phenotypes by releasing Transportin-1 (TNPO1) from the cytoplasm, restoring the TNPO1 pathway and allowing hnRNPA1 and NUP153 nuclear import, TPR anchorage at the nuclear pore complexes and RanGTP gradient re-balancing. We have promoted NAT10 inhibition by two ways in normal or patient derived primary skin fibroblasts; the NAT10 inhibitor Remodelin, and an siRNA directly targeting NAT10 (siNAT10). In addition, we have also used an siRNA against TNPO1 and a combined siTNPO1 and siNAT10 treatment. This is a 2-factor design, with treatment (Remodelin vs untreated, or siNAT10 vs siCT) and condition (HGPS vs normal fibroblasts) as the two conditions. Transcriptional profiling was performed using HumanHT-12 v4 Expression BeadChip microarrays, and all conditions were run in triplicate.
Project description:Hutchinson-Gilford progeria syndrome (HGPS) is a genetic disorder displaying features reminiscent of premature senescence caused by germline mutations in the LMNA gene encoding lamin A and C, essential components of the nuclear lamina. By studying a family with homozygous LMNA mutation (K542N), we showed that HGPS can also be caused by mutations affecting both isoforms, lamin A and C (J Med Genet 2004;41:609M-^V614). With the aim to elucidate the molecular mechanisms underlying the pathogenesis of lamin A/C-related (hereditary) HGPS, we investigated primary cultured skin fibroblasts from affected homozygous K542N carriers (n=3), healthy heterozygotes (n=3), and controls (n=3) for differences in global gene expression using GeneChip Human Genome U133 Plus 2.0 arrays (Affymetrix UK Ltd.).
Project description:Primary skin fibroblasts from HGPS patients and an age-matched control wild-type individuals were challenged in a standard transformation assay by retroviral introduction of TERT (T), V12-HRAS (R) and SV40 large and small T antigens (S). TERT-Immortalized cell lines from the same sources were also generated. Abstract: Advanced age and DNA damage accumulation are strong risk factors for cancer. The premature-aging disorder Hutchinson Gilford Progeria Syndrome (HGPS) provides a unique opportunity to study the interplay between DNA damage and aging-associated tumor mechanisms, since HGPS patients do not develop tumors despite elevated levels of DNA damage. Here, we have used HGPS patient cells to identify a protective mechanism to oncogenesis. We find that HGPS cells are resistant to neo-plastic transformation. This resistance is mediated by the bromodomain protein BRD4, which exhibits altered genome-wide binding patterns in transformation-resistant cells leading to inhibition of oncogenic de-differentiation. BRD4 also in-hibits, albeit to a lower extent, the tumorigenic potential of transformed cells from healthy individuals and BRD4-mediated tumor protection is clinically relevant, since a BRD4 gene signature predicts positive clinical outcome in breast and lung cancer. Our results demonstrate a protective function for BRD4 and suggest tissue-specific functions for BRD4 in tumorigenesis. 2 independent cell lines are included for each of the 4 groups (TERT-WT, TRS-WT, TERT-HGPS and TRS-HGPS)
Project description:Primary skin fibroblasts from a HGPS patient and an age-matched control wild-type individual were challenged in a standard transformation assay by retroviral introduction of TERT (T), V12-HRAS (R) and SV40 large and small T antigens (S). Knock-down of BRD4 in this TRS-HGPS cell line (TRS-HGPS-shBRD4) was achieved by retroviral introduction of independent shRNAs (shBRD4-1 to -3) Abstract: Advanced age and DNA damage accumulation are strong risk factors for cancer. The premature-aging disorder Hutchinson Gilford Progeria Syndrome (HGPS) provides a unique opportunity to study the interplay between DNA damage and aging-associated tumor mechanisms, since HGPS patients do not develop tumors despite elevated levels of DNA damage. Here, we have used HGPS patient cells to identify a protective mechanism to oncogenesis. We find that HGPS cells are resistant to neo-plastic transformation. This resistance is mediated by the bromodomain protein BRD4, which exhibits altered genome-wide binding patterns in transformation-resistant cells leading to inhibition of oncogenic de-differentiation. BRD4 also in-hibits, albeit to a lower extent, the tumorigenic potential of transformed cells from healthy individuals and BRD4-mediated tumor protection is clinically relevant, since a BRD4 gene signature predicts positive clinical outcome in breast and lung cancer. Our results demonstrate a protective function for BRD4 and suggest tissue-specific functions for BRD4 in tumorigenesis. 2 biological replicates are included for TRS-WT and TRS-HGPS cell lines. 3 biological replicates are included for TRS-HGPS-shBRD4 (derived from 3 independent shRNAs against BRD4)