Telomere length effect on genes near the telomere in myoblasts
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE48973 | GEO | 2014/07/17
SECONDARY ACCESSION(S): PRJNA212501
REPOSITORIES: GEO
Similar Datasets
Project description:We examined differential expression of genes within 10MBs of telomeres in myoblasts with long or short telomeres We offer telomere looping with telomere length as a partial mechanistic explanation for the changes gene expression that is observed. Compare expression of genes within 10MB of the telomere in normal myoblasts with long (15 kb) and short (6 kb) telomeres.
2014-07-17 | E-GEOD-48973 | biostudies-arrayexpress
Project description:Reporter genes inserted immediately adjacent to telomeres are frequently repressed in cells of model organisms as well as human cells, a phenomena referred to as telomere position effect (TPE). TPE has been proposed to be involved in regulation of cellular senescence, cancer and aging. However, the identification of endogenous genes in human cells regulated by natural telomeres has not been reported. Here we show that the expression of interferon simulated gene 15 (ISG15, located on 1p36.33, G1P2) varies with telomere length. ISG15 expression (RNA and protein) increases in human cells with short telomeres, and decreases with the elongation of telomeres by human telomerase reverse transcriptase (hTERT). The up-regulation of ISG15 is independent of p53 and type I interferon, and is not due to replicative senescence and DNA damage. In human skin specimens obtained from various aged individuals, ISG15 was up-regulated in a subset of cells in older individuals. Our results demonstrate that endogenous human genes can be regulated by the length of telomeres prior to the onset of DNA damage signals, and it suggests that telomeres may be involved in the regulation of human physiology that contributes to the process of aging. Keywords: cell type comparison
2007-12-07 | GSE6799 | GEO
Project description:We performed single-molecule telomere length and telomere fusion analysis in patients at different stages of chronic lymphocytic leukaemia (CLL). Our work identified the shortest telomeres ever recorded in primary human tissue reinforcing the concept that there is significant cell division in CLL. Furthermore, we provide direct evidence that critical telomere shortening, dysfunction and fusion contribute to disease progression. The frequency of short telomeres and fusion events increased with advanced disease, but importantly these were also found in a subset of early-stage patient samples indicating that these events can precede disease progression. Sequence analysis of fusion events isolated from individuals with the shortest telomeres revealed limited numbers of repeats at the breakpoint, sub-telomeric deletion and microhomology. Array-CGH analysis of individuals displaying evidence of telomere dysfunction revealed large-scale genomic rearrangements that were concentrated in the telomeric regions; this was not observed in samples with longer telomeres. Array CGH was undertaken on six individuals (five CLL stage C and one stage A) that displayed evidence of telomere dysfunction, and four (three CLL stage A and one stage B) that displayed longer and apparently stable telomeres.
2010-05-28 | E-GEOD-22016 | biostudies-arrayexpress
Project description:Telomeres, TTAGGGn DNA repeat sequences located at the ends of eukaryotic chromosomes, play a pivotal role in ageing and are targets of DNA damage and DNA damage response. Although short telomeres have been implicated in heart failure, little is known about the role of telomeres in cardiomyocytes.To fill this gap in knowledge, we studied myocardial ageing in the form of telomere lengths under isogenic background.
2023-12-31 | GSE217702 | GEO
Project description:Telomeres, TTAGGGn DNA repeat sequences located at the ends of eukaryotic chromosomes, play a pivotal role in ageing and are targets of DNA damage and DNA damage response. Although short telomeres have been implicated in heart failure, little is known about the role of telomeres in cardiomyocytes.To fill this gap in knowledge, we studied myocardial ageing in the form of telomere lengths under isogenic background.
2023-12-31 | GSE217701 | GEO
Project description:Telomeres, TTAGGGn DNA repeat sequences located at the ends of eukaryotic chromosomes, play a pivotal role in ageing and are targets of DNA damage and DNA damage response. Although short telomeres have been implicated in heart failure, little is known about the role of telomeres in cardiomyocytes.To fill this gap in knowledge, we studied myocardial ageing in the form of telomere lengths under isogenic background.
2023-12-31 | GSE230455 | GEO
Project description:Diseases caused by gene haploinsufficiency in humans commonly lack a phenotype in mice heterozygous for the orthologous factor, although the source of this discrepancy is unknown. The inability to accurately model human disease in mice impedes the study of complex phenotypes and critically limits the discovery and testing of potential therapeutics. Laboratory mice have longer telomeres (>40 kilobases (kb)) compared to humans (~5-15 kb), potentially protecting them from age-related disease caused by haploinsufficiency. In humans, heterozygous non-sense mutations in the transcription factor, NOTCH1 (N1), lead to severe age-dependent aortic valve (AV) calcification. However, mice heterozygous for N1 do not develop calcific AV disease (CAVD)5. Here, we show that telomere shortening is sufficient to elicit age-dependent cardiac valve disease in N1+/- mice that closely mimics the human disease and that progressive shortening correlates with severity of disease, extending to AV thickening in the neonate. N1 haploinsufficiency led to increased proliferation in valves that further reduced telomere length. Calcified AVs exhibited downregulation of osteoclast factors and upregulation of pro-calcific regulatory nodes concordant with gene network alterations in human N1 heterozygous endothelial cells. Dysregulated genes in valves were enriched for those that have promoters normally contacted by telomere looping. These findings reveal a critical role for telomere length in a mouse model of age-dependent human disease that may have broader implications and provides an in vivo model in which to test therapeutic candidates to prevent or delay the progression of CAVD.
2017-08-22 | GSE83963 | GEO
Project description:Limitless reproductive potential is one of the hallmarks of cancer cells1. This ability is accomplished by maintaining telomeres, which erosion otherwise causes cellular senescence or death. Human cancer cells often maintain shorter telomeres than do cells in surrounding normal tissues2-5. While most cancer cells activate telomerase, which can elongate telomeres6, it remains elusive why cancer cells keep telomeres short. Here we show that forced elongation of telomeres in cancer cells promotes their differentiation in a tumor microenvironment in vivo. We elongated telomeres of human prostate cancer PC-3 cells, which possess short telomeres7, by enhancing their telomerase activity. The resulting cells with long telomeres retain an ability to form tumors in a mouse xenograft model. Strikingly, these tumors exhibit many duct-like structures and reduced N-cadherin expression, reminiscent of well-differentiated adenocarcinoma. These phenotypic changes are caused by telomere elongation per se but not enhanced telomerase activity. Gene expression profiling revealed that telomere elongation correlates with inhibition of cell-cycle processes. Together, our results suggest a functional contribution of short telomeres to tumor malignancy by regulating cancer cell differentiation. Two samples are telomere-elongated cells, both in the presence and absence of the exogenous hTERT. The other two samples are control cell lines.
2013-05-31 | E-GEOD-36649 | biostudies-arrayexpress
Project description:Telomere erosion causes cell mortality, suggesting that longer telomeres allow greater number of cell division. In telomerase-positive human cancer cells, however, telomeres are often kept shorter than the surrounding normal tissues. Recently, we have shown that telomere elongation in cancer cells represses innate immune genes and promotes their differentiation in vivo. This implies that short telomeres contribute to cancer malignancy, but it is unclear how such genetic repression is caused by long telomeres. Here we report that telomeric repeat-containing RNA (TERRA) induces genome-wide alteration of gene expression in telomere-elongated cancer cells in vivo. Using three different cell lines, we found that telomere elongation upregulates TERRA and downregulates innate immune genes in vivo xenograft tumors. Most of the suppressed genes belonged to innate immune system categories and were upregulated in various cancers. We propose that TERRA G4 counteracts cancer malignancy through suppression of innate immune genes. Four samples are telomere-elongated cells (PC3/LhTERTL, PC3/LhTERTL/cre, HBC4/hTERT and MKN74/hTERT), and the other four samples are control cell lines.
2015-02-05 | E-GEOD-56177 | biostudies-arrayexpress
Project description:Limitless reproductive potential is one of the hallmarks of cancer cells1. This ability is accomplished by maintaining telomeres, which erosion otherwise causes cellular senescence or death. Human cancer cells often maintain shorter telomeres than do cells in surrounding normal tissues2-5. While most cancer cells activate telomerase, which can elongate telomeres6, it remains elusive why cancer cells keep telomeres short. Here we show that forced elongation of telomeres in cancer cells promotes their differentiation in a tumor microenvironment in vivo. We elongated telomeres of human prostate cancer PC-3 cells, which possess short telomeres7, by enhancing their telomerase activity. The resulting cells with long telomeres retain an ability to form tumors in a mouse xenograft model. Strikingly, these tumors exhibit many duct-like structures and reduced N-cadherin expression, reminiscent of well-differentiated adenocarcinoma. These phenotypic changes are caused by telomere elongation per se but not enhanced telomerase activity. Gene expression profiling revealed that telomere elongation correlates with inhibition of cell-cycle processes. Together, our results suggest a functional contribution of short telomeres to tumor malignancy by regulating cancer cell differentiation. Two cell lines are telomere-elongated cells, both in the presence and absence of the exogenous hTERT. The other two lines are control PC-3 cell lines. We extracted RNA from four independent xenograft tumors per original cell line.
2013-05-31 | E-GEOD-41559 | biostudies-arrayexpress