Gene expression profile of HGPS skin fibroblasts upon treatment with JH4
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE84147 | GEO | 2016/07/08
SECONDARY ACCESSION(S): PRJNA328147
REPOSITORIES: GEO
Similar Datasets
Project description:Transcriptionally active loci are particularly prone to breakage and mounting evidence suggest that DNA Double-Strand Breaks arising in active genes are handled by a dedicated repair pathway, Transcription-Coupled DSB Repair (TC-DSBR), that entails R-loop accumulation and dissolution. Here, we uncovered a function for the Bloom RecQ DNA helicase (BLM) in TC-DSBR in human cells. BLM is recruited in a transcription dependent-manner at DSBs where it fosters resection, RAD51 binding and accurate Homologous Recombination repair. However, in an R-loop dissolution-deficient background, we found that BLM promotes cell death. We report that upon excessive R-loop accumulation, DNA synthesis is enhanced at DSBs, in a anner that depends on BLM and POLD3. Altogether our work unveils a role for BLM at DSBs in active chromatin, and highlights the toxic potential of RNA:DNA hybrids that accumulate at transcription-associated DSBs.
2022-04-13 | E-MTAB-11592 | biostudies-arrayexpress
Project description:Replication fork reversal is a key protective mechanism against replication stress in higher eukaryotic cells and occurs via a series of coordinated enzymatic reactions. The Bloom syndrome gene product, BLM, is a member of the highly conserved RecQ helicase family and has been implicated in this process, but its precise regulation and role remain poorly understood. Here, we show that, upon replication stress, the GCFC domain-containing protein TFIP11 competes with the BLM helicase for association with stalled replication forks, thereby facilitates RAD51-mediated stalled fork reversal. Consequently, loss of TFIP11 results in aberrant accumulation of BLM at stalled forks, which in turn compromises RAD51 recruitment, impairs replication stress-induced fork reversal and slowing, hypersensitizes cells to replication stress-inducing agents, and enhances chromosomal instability. These findings reveal a previously unidentified regulatory mechanism that modulates the activities of BLM and RAD51 at stalled forks and thus genome integrity.
2024-05-24 | PXD042222 | Pride
Project description:Systemic sclerosis (SSc) is characterized by intractable multiorgan fibrosis caused by vascular and immune dysfunction. Currently, effective therapeutic options for patients with SSc are limited. Nitrate, an abundant nutrient in the diet, has been demonstrated to be preventative and therapeutic for several diseases. To determine whether nitrate can slow or reverse SSc progression, topical application of nitrate delivered by dissolving microneedles was used to treat a bleomycin (BLM)-induced dermal fibrosis mouse model. In this study, nitrate considerably attenuated dermal thickness, stiffness, and collagen deposition.To examine the nitrate regulation of gene expression at the genome-wide level, bulk RNA sequencing of skin was performed. Bulk RNA sequencing of skin revealed that Cd4 was a key hub gene in SSc nitrate therapy. Additionally, BLM-induced cytokines and chemokines were inhibited by nitrate, and CD4+ T cells infiltration markedly declined. Il4, Il6, Il13, and Tgfb expression in CD4+ T cells isolated from skin biopsies also significantly decreased. Mechanistically, Il1rl1, a type2 immune response inducer, was markedly repressed in isolated CD4+ T cells and dermal tissues after nitrate treatment. Remarkably, compared with wild type mice, mice lacking Il1rl1 showed impaired transcriptional profiles after intradermal BLM injection. Adoptive transfer of ST2+CD4+ T cells promoted bleomycin-induced Rag2-/- mice dermal fibrosis. Collectively, these findings demonstrate that nitrate targeting ST2+CD4+ T cells is an effective therapeutic option for SSc.
2024-06-04 | GSE264187 | GEO
Project description:The poly (ADP-ribose) polymerases (PARPs) inhibitors are an exciting new class of agents that have shown efficacy in treating various cancers, especially these harboring BRCA1/2 mutations. The cancer associated BRCA1/2 mutations disrupt DNA double strand break (DSB) repair by homologous recombination (HR). PARP inhibitors (PARPi) have been applied to trigger synthetic lethality in BRCA1/2-mutated cancer cells by promoting accumulation of toxic DSBs. Unfortunately, PARP inhibitor (PARPi) resistance is common and develops through multiple mechanisms. Restoration of HR and/or stabilizing replication forks are two major mechanisms of PARPi resistance in BRCA1/2-mutated cells. To further understand the mechanisms of drug resistance to PARPi, we undertook an unbiased approach with a CRISPR-pooled library to screen new genes whose loss-of-function confers resistance to PARPi olaparib. We identified ZNF251, a transcription factor, and confirmed its loss-of-function led to the PARPi resistance in BRCA1-mutated breast and ovarian cancer lines. Elevated activities of both HR and non-homologous end joining (NHEJ) repair were detected in cancer cells harboring BRCA1 mutation and ZNF251 deletion (BRCA1mut+ZNF251del) and were associated with enhanced expression of RAD51 and Ku70/Ku80, respectively. Furthermore, we showed that DNA-PKcs inhibitor restored sensitivity of BRCA1mut+ZNF251del cells to PARPi. Taken together, our study identified a novel gene whose loss of function conferred resistance to PARPi, providing new insight into signaling pathways that contribute to acquired resistance in BRCA1-mutated breast and ovarian cancers.
2023-05-31 | GSE205221 | GEO
Project description:While BRCA-related cancers respond well to double-strand break (DSB) inducing agents, resistance is a serious clinical problem. One mechanism of resistance is reversion of the BRCA1 mutation, suggesting that BRCA1 function is required for resistance. Here we show that secondary Brca1 mutations are not always necessary, since residual activity of the mutant BRCA1 protein can be sufficient for tumor cells to withstand treatment. Genomic profiling and RAD51 foci formation are currently seen as potential biomarkers to stratify patients for therapies targeting homologous recombination deficiency (HRD). However, we show that while mouse mammary tumors with different Brca1 mutations have identical genomic profiles, they respond considerably different to HRD targeted therapy. It may therefore be useful to stratify patients according to functional assays and the underlying BRCA1 mutation.
2013-12-01 | GSE43997 | GEO
Project description:While BRCA-related cancers respond well to double-strand break (DSB) inducing agents, resistance is a serious clinical problem. One mechanism of resistance is reversion of the BRCA1 mutation, suggesting that BRCA1 function is required for resistance. Here we show that secondary Brca1 mutations are not always necessary, since residual activity of the mutant BRCA1 protein can be sufficient for tumor cells to withstand treatment. Genomic profiling and RAD51 foci formation are currently seen as potential biomarkers to stratify patients for therapies targeting homologous recombination deficiency (HRD). However, we show that while mouse mammary tumors with different Brca1 mutations have identical genomic profiles, they respond considerably different to HRD targeted therapy. It may therefore be useful to stratify patients according to functional assays and the underlying BRCA1 mutation.
2011-12-01 | GSE30710 | GEO
Project description:While BRCA-related cancers respond well to double-strand break (DSB) inducing agents, resistance is a serious clinical problem. One mechanism of resistance is reversion of the BRCA1 mutation, suggesting that BRCA1 function is required for resistance. Here we show that secondary Brca1 mutations are not always necessary, since residual activity of the mutant BRCA1 protein can be sufficient for tumor cells to withstand treatment. Genomic profiling and RAD51 foci formation are currently seen as potential biomarkers to stratify patients for therapies targeting homologous recombination deficiency (HRD). However, we show that while mouse mammary tumors with different Brca1 mutations have identical genomic profiles, they respond considerably different to HRD targeted therapy. It may therefore be useful to stratify patients according to functional assays and the underlying BRCA1 mutation. We performed aCGH on mammary tumor DNA from KB1C61GP (n=20), littermate KB1P (n=18) and KP mice (n=19). Spleen DNA of the same animal was used as control material.
2011-12-01 | E-GEOD-30710 | biostudies-arrayexpress
Project description:While BRCA-related cancers respond well to double-strand break (DSB) inducing agents, resistance is a serious clinical problem. One mechanism of resistance is reversion of the BRCA1 mutation, suggesting that BRCA1 function is required for resistance. Here we show that secondary Brca1 mutations are not always necessary, since residual activity of the mutant BRCA1 protein can be sufficient for tumor cells to withstand treatment. Genomic profiling and RAD51 foci formation are currently seen as potential biomarkers to stratify patients for therapies targeting homologous recombination deficiency (HRD). However, we show that while mouse mammary tumors with different Brca1 mutations have identical genomic profiles, they respond considerably different to HRD targeted therapy. It may therefore be useful to stratify patients according to functional assays and the underlying BRCA1 mutation. We performed aCGH on mammary tumor DNA from KB1(185stop)P (n=20), KB1(5382stop)P (n=20) and littermate KB1P (n=22). Spleen DNA of the same animal was used as control material.
2013-12-01 | E-GEOD-43997 | biostudies-arrayexpress
Project description:Although PARP inhibitors (PARPi) now form part of the standard-of-care for the treatment of homologous recombination defective cancers, de novo and acquired resistance limits their overall effectiveness. Previously, overexpression of the BRCA1-∆11q splice variant has been shown to cause PARPi resistance. How cancer cells achieve increased BRCA1-∆11q expression has remained unclear. Using isogenic cells with different BRCA1 mutations, we show that reduction in HUWE1 leads to increased levels of BRCA1-∆11q and PARPi resistance. This effect is specific to cells able to express BRCA1-∆11q (e.g. BRCA1 exon 11 mutant cells) and is not seen in BRCA1 mutants that cannot express BRCA1-∆11q, nor in BRCA2 mutant cells. As well as increasing levels of BRCA1-∆11q protein in exon 11 mutant cells, HUWE1 silencing also restores RAD51 nuclear foci and platinum salt resistance. HUWE1 catalytic domain mutations were also seen in a case of PARPi resistant, BRCA1 exon 11 mutant, high grade serous ovarian cancer. These results suggest how elevated levels of BRCA1-∆11q and PARPi resistance can be achieved, identify HUWE1 as a candidate biomarker of PARPi resistance for assessment in future clinical trials and illustrate how some PARPi resistance mechanisms may only operate in patients with particular BRCA1 mutations.
2023-07-18 | PXD040430 | Pride
Project description:Focal adhesion kinase (FAK) is required for the expression of pro-inflammatory genes that inhibit anti-tumour immunity. Here, we show a novel and crucial role for the dual-function cytokine IL33 in FAK-dependent immune evasion. Specifically, nuclear FAK is required for the expression of IL33, the chemokine Ccl5 and the soluble form of the IL33 receptor, sST2, which are required for evasion of CD8+ T-cell-mediated anti-tumour immunity. Mechanistically, nuclear IL33 associates with FAK and a network of chromatin modifiers and transcriptional regulators, including Taf9, WDR82 and BRD4, while sST2 likely negates effects of IL33 secreted into the tumour microenvironment by infiltrating host immune cells. Finally, protein interaction network analysis implies that nuclear FAK–IL33 complexes impact on transcription factors that regulate NFkB and chemokines like Ccl5 downstream. Our data therefore provide new mechanistic insight into how FAK controls the tumour immune environment via a FAK–IL33/sST2 pathway and demonstrate a novel role for nuclear IL33 downstream of FAK as a component of transcription regulatory complexes that critically modulate anti-tumour immunity.
2017-12-06 | PXD007698 | Pride