Homo sapiens
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PROVIDER: PRJNA132283 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:16 replication error proficient (RER-/MSI-) and 14 replication error deficient (RER+/MSI+) colorectal cancer cell lines Replication error deficient (RER+) colorectal cancers are a distinct subset of colorectal cancers, characterised by inactivation of the DNA mismatch repair system. They are typically pseudodiploid, accumulate mutations in repetitive sequences as a result of their mismatch repair deficiency, and have distinct pathologies. Regulatory sequences controlling all aspects of mRNA processing, including especially message stability are found in the 3âUTR sequence of most genes. The relevant sequences are typically A/U rich elements and/or U repeats. Microarray analysis of 14 RER+ (deficient) and 16 RER- (proficient) colorectal cancer (CRC) cell lines confirms a striking difference in expression profiles. Analysis of the incidence of mononucleotide repeat sequences in the 3âUTRs, 5âUTRs and coding sequences of those genes most differentially expressed in RER+ versus â cell lines has shown that much of this differential expression can be explained by the occurrence of a massive enrichment of genes with 3âUTR T repeats longer than 11 base pairs in the most differentially expressed genes. This enrichment was confirmed by analysis of two published consensus sets of RER differentially expressed probe sets for a large number of primary colorectal cancers. Sequence analysis of the 3âUTRs of a selection of the most differentially expressed genes shows that they all contain deletions in these repeats in all RER+ cell lines studied. These data strongly imply that deregulation of mRNA stability through accumulation of mutations in repetitive regulatory 3âUTR sequences underlies the striking difference in expression profiles between RER+ and RER- colorectal cancers. 16 replication error proficient (RER-/MSI-) and 14 replication error deficient (RER+/MSI+) colorectal cancer cell lines.
2010-10-19 | E-GEOD-24795 | biostudies-arrayexpress
Project description:16 replication error proficient (RER-/MSI-) and 14 replication error deficient (RER+/MSI+) colorectal cancer cell lines Replication error deficient (RER+) colorectal cancers are a distinct subset of colorectal cancers, characterised by inactivation of the DNA mismatch repair system. They are typically pseudodiploid, accumulate mutations in repetitive sequences as a result of their mismatch repair deficiency, and have distinct pathologies. Regulatory sequences controlling all aspects of mRNA processing, including especially message stability are found in the 3’UTR sequence of most genes. The relevant sequences are typically A/U rich elements and/or U repeats. Microarray analysis of 14 RER+ (deficient) and 16 RER- (proficient) colorectal cancer (CRC) cell lines confirms a striking difference in expression profiles. Analysis of the incidence of mononucleotide repeat sequences in the 3’UTRs, 5’UTRs and coding sequences of those genes most differentially expressed in RER+ versus – cell lines has shown that much of this differential expression can be explained by the occurrence of a massive enrichment of genes with 3’UTR T repeats longer than 11 base pairs in the most differentially expressed genes. This enrichment was confirmed by analysis of two published consensus sets of RER differentially expressed probe sets for a large number of primary colorectal cancers. Sequence analysis of the 3’UTRs of a selection of the most differentially expressed genes shows that they all contain deletions in these repeats in all RER+ cell lines studied. These data strongly imply that deregulation of mRNA stability through accumulation of mutations in repetitive regulatory 3’UTR sequences underlies the striking difference in expression profiles between RER+ and RER- colorectal cancers.
2010-10-19 | GSE24795 | GEO
Project description:An enduring issue in evolutionary and cancer biology is how replication infidelity influences genome composition and vice versa. Here we examine this issue by sequencing the genomes of diploid budding yeast strains that are either mismatch repair (MMR) proficient or deficient and encode wild type or mutator variants of the three major nuclear DNA replicases. Analysis of over 43,000 mutations that accumulated in the absence of selective pressure demonstrates that the nuclear DNA replication machinery generates less than one mismatch per genome and in combination with MMR, achieves a genome-wide per base error rate of 1.7 x 10-10. Absent both MMR and purifying selection, replication error patterns strongly depend on replication origin proximity, replication fork direction, and the local DNA sequence. Preferred sequences were observed for base substitutions and deletions. Error rates also vary with replication time, in linker versus nucleosome-bound DNA, in 5'- and 3'-untranslated regions, in coding regions and in intergenic DNA. This genome-wide view shows that replication fidelity is amazingly high but heterogeneous, in patterns that suggest the underlying mechanisms by which replication modulates genome stability and composition and vice versa. Six to ten isolates were sequenced for each combination of DNA polymerase (WT, pol1-L868M, pol2-M644G, pol3-L612M) and mismatch repair (proficient, deficient) genotypes. A single WT isolate was sequenced following micrococcal nuclease digestion.
2014-08-25 | E-GEOD-56939 | biostudies-arrayexpress
Project description:An enduring issue in evolutionary and cancer biology is how replication infidelity influences genome composition and vice versa. Here we examine this issue by sequencing the genomes of diploid budding yeast strains that are either mismatch repair (MMR) proficient or deficient and encode wild type or mutator variants of the three major nuclear DNA replicases. Analysis of over 43,000 mutations that accumulated in the absence of selective pressure demonstrates that the nuclear DNA replication machinery generates less than one mismatch per genome and in combination with MMR, achieves a genome-wide per base error rate of 1.7 x 10-10. Absent both MMR and purifying selection, replication error patterns strongly depend on replication origin proximity, replication fork direction, and the local DNA sequence. Preferred sequences were observed for base substitutions and deletions. Error rates also vary with replication time, in linker versus nucleosome-bound DNA, in 5'- and 3'-untranslated regions, in coding regions and in intergenic DNA. This genome-wide view shows that replication fidelity is amazingly high but heterogeneous, in patterns that suggest the underlying mechanisms by which replication modulates genome stability and composition and vice versa.
2014-08-25 | GSE56939 | GEO
Project description:Lynch syndrome and Familial colorectal cancer type X (FCCTX) are clinically diagnosed using the same criteria, but genomic differences exist between these two groups and the genomic profiles share similarities with their sporadic counterparts, mismatch repair (MMR) deficient and proficient tumors, respectively. Array-based comparative genomic hybridization was performed on 91 tumors, comprising 23 Lynch syndrome (AH), 23 FCCTX (AA), 23 sporadic MMR deficient (AM) and 22 sporadic MMR proficient tumors, in order to identify differences between Lynch syndrome and FCCTX.
2012-06-01 | E-GEOD-38405 | biostudies-arrayexpress
Project description:DNA replication errors occurring in mismatch repair (MMR) deficient cells persist as mismatch mutations and predispose to a range of tumors. Here, we sequenced the first whole-genomes from MMR-deficient tumors and observed that mutation rates were drastically increased relative to MMR-proficient endometrial tumors.
| EGAS00001000182 | EGA
Project description:Aberrant glycosylation is a crucial strategy employed by cancer cells to evade cellular immunity. However, homologous recombination (HR) status-dependent glycosylation has never been explored therapeutically. Here, we show that the inhibition of branched N-glycans sensitizes HR-proficient, but not HR-deficient, epithelial ovarian cancers (EOCs) to immune checkpoint blockade (ICB). In contrast to fucosylation whose inhibition sensitizes EOCs to anti-PD-L1 immunotherapy regardless of HR-status, we observe a unique enrichment of branched N-glycans on HR-proficient compared to HR-deficient EOCs. Mechanistically, BRCA1/2 transcriptionally promotes the expression of MGAT5, the enzyme responsible for catalyzing branched N-glycans. The branched N-glycans on HR-proficient tumors augment their resistance to anti-PD-L1 by enhancing its binding with PD-1 on CD8_ T cells. In orthotopic syngeneic EOC mouse models, inhibiting branched N-glycans, using 2-Deoxy-D-glucose, sensitizes HR-proficient, but not HR-deficient EOCs, to anti-PD-L1. These findings indicate branched N-glycans as promising therapeutic targets whose inhibition sensitizes HR-proficient EOCs to ICB by overcoming immune evasion
2024-09-29 | GSE244367 | GEO
Project description:Aberrant glycosylation is a crucial strategy employed by cancer cells to evade cellular immunity. However, homologous recombination (HR) status-dependent glycosylation has never been explored therapeutically. Here, we show that the inhibition of branched N-glycans sensitizes HR-proficient, but not HR-deficient, epithelial ovarian cancers (EOCs) to immune checkpoint blockade (ICB). In contrast to fucosylation whose inhibition sensitizes EOCs to anti-PD-L1 immunotherapy regardless of HR-status, we observe a unique enrichment of branched N-glycans on HR-proficient compared to HR-deficient EOCs. Mechanistically, BRCA1/2 transcriptionally promotes the expression of MGAT5, the enzyme responsible for catalyzing branched N-glycans. The branched N-glycans on HR-proficient tumors augment their resistance to anti-PD-L1 by enhancing its binding with PD-1 on CD8_ T cells. In orthotopic syngeneic EOC mouse models, inhibiting branched N-glycans, using 2-Deoxy-D-glucose, sensitizes HR-proficient, but not HR-deficient EOCs, to anti-PD-L1. These findings indicate branched N-glycans as promising therapeutic targets whose inhibition sensitizes HR-proficient EOCs to ICB by overcoming immune evasion
2024-03-11 | GSE244012 | GEO
Project description:Most BRCA1-deficient BLBCs carry a dysfunctional INK4-RB pathway. Thus, we have created genetically engineered mice with Brca1 loss and deletion of p16INK4A, or separately p18INK4C, to model the deficient INK4-RB signaling in human BLBC. By using these mutant mice and human BRCA1 deficient and proficient breast cancer tissues and cells, we tested if there exists a druggable target in BRCA1 deficient breast cancers.
2021-01-27 | GSE155239 | GEO
Project description:Polybromo-1 (PBRM1), which encodes a specific subunit of the pBAF chromatin remodeling complex, is inactivated in multiple malignancies including 50% of clear cell renal cell carcinoma. At present, a therapeutic strategy that selectively targets PBRM1 defects does not exist. PBRM1 is involved in multiple cellular processes including transcription, replication and DNA repair. Using high-throughput screens and multiple isogenic and non-isogenic models, we found that PBRM1 defects cause synthetic lethality with several clinical PARP inhibitors, both in vitro and in vivo. This effect was enhanced using combinations with either small molecule ATR or BET inhibitors. Mechanistically, PBRM1 defects caused increased replication stress, R-loop formation and genomic instability that was exacerbated by PARP inhibitors. We also found that PARP and ATR inhibitors activate the cGAS-STING innate immunity pathway in PBRM1-deficient but not in PBRM1-proficient cells. These data provide the pre-clinical rationale for assessing PARP inhibitors as a monotherapy or in combination with ATR inhibitors or immune checkpoint inhibitors, in patients with PBRM1-deficient cancers.
2022-02-21 | PXD017826 | Pride