Similar Datasets
Project description:Richter syndrome (RS) occurs in up to 15% of patients with chronic lymphocytic leukemia (CLL). While RS, usually represented by the histologic transformation to a diffuse large B-cell lymphoma (DLBCL), is associated with a very poor outcome, especially when clonally related to the pre-existing CLL, mechanisms leading to RS have not been clarified yet. To better understand the pathogenesis of RS, we analyzed a series of cases including: 59 RS, 28 CLL-phase of RS, 315 CLL and 127 de novo DLBCL. RS demonstrated a genomic complexity intermediate between CLL and DLBCL. Cell cycle deregulation via inactivation of TP53 and of CDKN2A was a main mechanism in the histologic transformation from CLL-phase, being present in approximately half of the cases, and affected the outcome of the RS patients. A second major subgroup was characterized by the presence of trisomy 12 and comprised one third of the cases. While RS shared some of the lesions seen in de novo DLBCL, its genomic profile was clearly separate. The CLL-phase preceding RS had not a generalized increase in genomic complexity when compared with untransformed CLL, but it presented clear differences in the frequency of specific genetic lesions.
2013-09-20 | GSE50252 | GEO
Project description:Human embryonic stem cells (hESC) and cancer cells rapidly divide with a short G1/S-phase causing increased replicative stress (RS). Since both in vitro cultured hESCs and most high-risk neuroblastomas have large chromosome 17q gains (17q+), we hypothesize that this may provide a "RS-resistance phenotype". We co-cultured parental cells and a derived hESC line with 17q+ under normal growth conditions and under RS. We could show a proliferative ad-vantage of hESC with 13q+17q+ over wild type by measurement of the cumulative growth and molecular analysis for chromosomal copy number analysis. To monitor effects of 17q+ on RS-resistance, cell cycle and transcriptome analysis were performed. In conclusion, we show that extra chromosomal aberrations, such as 17q+, provide proliferative advantage to hESC under RS and suggest that this phenomenon explains the high incidence of 17q+ in in vitro cultured hESC lines.
2021-05-11 | GSE155181 | GEO
Project description:Senescence, a stable state of growth arrest, affects many physiological and pathophysiological processes, especially aging. Previous work has indicated that transcription factors (TFs) play a role in regulating senescence. However, a systematic study of regulatory TFs during replicative senescence (RS) using multi-omics analysis is still lacking. Here, we generated time-resolved RNA-seq, reduced representation bisulfite sequencing (RRBS) and ATAC-seq datasets during RS of mouse skin fibroblasts, which demonstrated that an enhanced inflammatory response and reduced proliferative capacity were the main characteristics of RS in both the transcriptome and epigenome. Through integrative analysis and genetic manipulation, we found that transcription factors E2F4, TEAD1 and AP-1 are key regulators of RS. Overexpression of E2f4 improved cellular proliferative capacity, attenuated SA-β-Gal activity and changed RS-associated differentially methylated sites (DMSs). Moreover, knockdown of Tead1 attenuated SA-β-Gal activity and partially altered the RS-associated transcriptome. In addition, knockdown of Atf3, one member of AP-1 superfamily TFs, reduced Cdkn2a (P16) expression in pre-senescent fibroblasts. Taken together, results of this study identified transcription factors regulating the senescence program through multi-omics analysis, providing potential therapeutic targets for anti-aging.
2021-10-08 | GSE185416 | GEO
Project description:Prostate cancer cell lines DU145 and LNCaP were purchased from the American Type Culture Collection. Radioresistant (RR) sublines were generated form these original parental radiosensitive (RS) cell lines. aCGH profiles of radiosensitive (RS) and radioresistant (RR) prostate cancer cell lines were measured and compared to normal DNA.
2019-10-11 | GSE134498 | GEO
Project description:Cellulosimicrobium sp. RS strain:RS Genome sequencing
| PRJNA1186700 | ENA
Project description:ralstonia solanacearum Rs strain:Rs Genome sequencing
| PRJNA221562 | ENA
Project description:Ringsideroblasts(RS) emerge as result of aberrant erythroid differentiation leading to excessive mitochondrial iron accumulation. This feature is characteristic for myelodysplastic syndromes with mutations in spliceosome gene SF3B1. However, RS can also be observed in patients diagnosed with acute myeloid leukemia (AML). The objective of this study was to characterize the presence of RS in a cohort of 109 AML and 17 high-risk MDS patients. Clinically, RS-AML is enriched for ELN adverse-risk (55%). In line with this finding, 35% of all cases had complex cytogenetic aberrancies and TP53 was most recurrently mutated in this cohort (42%), followed by DNMT3A (29%), RUNX1 (21%) and ASXL1 (19%). In contrast to RS-MDS, the incidence of SF3B1 mutations was low (8%). Whole exome sequencing and SNP array analysis on a subset of patients did not uncover one single defect underlying the RS phenotype. Shared genetic defects between erythroblasts and total mononuclear cell fraction indicate common ancestry for the erythroid lineage and the myeloid blast cells in RS-AML patients. Gene expression analysis by performing RNA sequencing on CD34+ AML cells revealed differential gene expression between RS-AML and a separate AML cohort, including genes involved in megakaryocytic/erythroid differentiation and mRNA splicing. Furthermore, several heme-metabolism-related genes were found upregulated in RS-AML, as was observed in SF3B1mut MDS. These results demonstrate that erythroblasts share ancestry with malignant myeloid blast cells in RS-AML. The genetic background of RS-AML differs from that of RS-MDS, however downstream effector pathways may be comparable, providing a possible explanation for presence of RS in AML.
2020-03-17 | GSE127861 | GEO
Project description:Since oncogenes induce DNA replication stress (RS), cancer cells rely on the intra S-phase checkpoint for survival. Consequently, RS inducing drugs and ATR and CHK1 inhibitors are exploited as anti-cancer therapy. However, drug resistance limits efficient use. This raises the question what determines sensitivity of individual cancer cells to RS. Here, we report that oncogenic RAS dampens the P53 checkpoint which confers sensitivity to RS. We demonstrate that inducible expression of HRASG12V leads to mild RS in RPE-hTERT cells and was sufficient to sensitize cells to ATR and CHK1 inhibitors. Using RNA-sequencing we discovered that P53 signaling is essential for the response to RS. However, oncogenic RAS attenuates transcription of P53 and its target genes. Accordingly, live cell imaging shows that HRASG12V exacerbates RS in S/G2-phase. Thus, our results suggest that hyperactivation of the MAPK pathway could predict durable responses to RS inducing drugs in cancer patients
2022-04-05 | GSE168987 | GEO