Similar Datasets
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: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 | GSE150645 | 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 | GSE150639 | GEO
Project description:We identified several hub genes and key pathways associated with GAC initiation and progression by analysising the microarray data on DEGs, whcih provided a detailed molecular mechanism underlying GAC occurrence and progression.
2019-06-10 | GSE118916 | GEO
Project description:The gene GLS generates the phosphate activated glutaminase C (GAC) isoform by alternative splicing. GAC, compared to the other isoform, kidney-type glutaminase (KGA), has been characterized as more active and particularly important for cancer cell growth. Very little is known about post-translational modifications regulating GAC function. Hereby we describe the identification of a phosphorylation on the serine 95, located at the GLS N-terminus, a domain shared by both isoforms. A GAC phosphomimetic mutant (S95D) ectopically expressed in breast cancer cells presented decreased enzymatic activity, and its expression impacted on cell’s glutamine uptake, glutamate release and intracellular glutamate levels (compared to expressing wild type GAC) without changing GAC sub-cellular localization. Curiously, replacing S95 by an alanine in the ectopically expressed GAC (S95A) increased cell proliferation and migration. Taken together, these results reveal that GAC is post-translationally regulated by phosphorylation, which impacts on cancer phenotype.
2018-08-13 | PXD008338 | Pride
Project description:Dysregulated transcription due to disruption in histone lysine methylation dynamics is an established contributor to tumorigenesis. However, whether analogous pathologic epigenetic mechanisms act directly on the ribosome to advance oncogenesis is unclear. Here we find that trimethylation of the core ribosomal protein L40 at lysine 22 (rpL40K22me3) by the lysine methyltransferase (KMT) SMYD5 regulates mRNA translation output to promote gastric adenocarcinoma (GAC) malignant progression with lethal peritoneal ascites. A biochemical-proteomic strategy identifies the mono-ubiquitin fusion protein partner rpL40 as the principal physiologic substrate of SMYD5 across diverse samples. Inhibiting the SMYD5-rpL40K22me3 axis in GAC cell lines reprograms protein synthesis to attenuate oncogenic gene expression signatures. SMYD5 and rpL40K22me3 are upregulated in GAC patient samples and negatively correlate with clinical outcomes. SMYD5 ablation in vivo in familial and sporadic mouse models of malignant GAC blocks metastatic disease including peritoneal carcinomatosis (PC). Suppressing SMYD5 methylation of rpL40 inhibits human cancer cell and patient-derived GAC xenograft growth and renders them hypersensitive to PI3K/mTOR inhibitors. Finally, combining SMYD5 depletion with PI3K/mTOR inhibition and CAR-T administration cures an otherwise lethal in vivo mouse model of aggressive GAC-derived PC. Together, our work uncovers a ribosome-based epigenetic mechanism that facilitates evolution of malignant GAC and nominates SMYD5 targeting as part of a potential cornerstone combination therapy to treat a deadly cancer.
2024-03-01 | GSE238257 | GEO
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:The phylum of Apicomplexa groups intracellular parasites that employ substrate-dependent gliding motility to invade host cells, egress from the infected cells and cross biological barriers. The glideosome associated connector (GAC) is a conserved protein essential to this process. GAC facilitates the association of actin filaments with surface transmembrane adhesins and the efficient transmission of the force generated by myosin translocation of actin to the cell surface substrate. Here, we present the crystal structure of Toxoplasma gondii GAC and reveal a unique, supercoiled armadillo repeat region that adopts a closed ring conformation. Characterisation of the membrane binding interface within the C-terminal PH domain as well as an N-terminal fragment necessary for association with F-actin suggest that GAC adopts multiple conformations. A multi-conformational model for assembly of GAC within the glideosome is proposed
2023-05-10 | PXD039335 | Pride