TY  - JOUR
A1  - Sbirkov, Yordan
A1  - Kwok, Colin
A1  - Bhamra, Amandeep
A1  - Thompson, Andrew J.
A1  - Gil, Veronica
A1  - Zelent, Arthur
A1  - Petrie, Kevin
T1  - Semi-quantitative mass spectrometry in AML cells identifies new non-genomic targets of the EZH2 methyltransferase
JF  - International Journal of Molecular Sciences
N2  - Alterations to the gene encoding the EZH2 (KMT6A) methyltransferase, including both gain-of-function and loss-of-function, have been linked to a variety of haematological malignancies and solid tumours, suggesting a complex, context-dependent role of this methyltransferase. The successful implementation of molecularly targeted therapies against EZH2 requires a greater understanding of the potential mechanisms by which EZH2 contributes to cancer. One aspect of this effort is the mapping of EZH2 partner proteins and cellular targets. To this end we performed affinity-purification mass spectrometry in the FAB-M2 HL-60 acute myeloid leukaemia (AML) cell line before and after all-trans retinoic acid-induced differentiation. These studies identified new EZH2 interaction partners and potential non-histone substrates for EZH2-mediated methylation. Our results suggest that EZH2 is involved in the regulation of translation through interactions with a number of RNA binding proteins and by methylating key components of protein synthesis such as eEF1A1. Given that deregulated mRNA translation is a frequent feature of cancer and that eEF1A1 is highly expressed in many human tumours, these findings present new possibilities for the therapeutic targeting of EZH2 in AML.
KW  - acute myeloid leukaemia
KW  - EZH2
KW  - mass spectrometry
KW  - methylation
KW  - eEF1A1
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285541
SN  - 1422-0067
VL  - 18
IS  - 7
ER  - 
TY  - JOUR
A1  - Maierhofer, Anna
A1  - Flunkert, Julia
A1  - Dittrich, Marcus
A1  - Müller, Tobias
A1  - Schindler, Detlev
A1  - Nanda, Indrajit
A1  - Haaf, Thomas
T1  - Analysis of global DNA methylation changes in primary human fibroblasts in the early phase following X-ray irradiation
JF  - PLoS ONE
N2  - Epigenetic alterations may contribute to the generation of cancer cells in a multi-step process of tumorigenesis following irradiation of normal body cells. Primary human fibroblasts with intact cell cycle checkpoints were used as a model to test whether X-ray irradiation with 2 and 4 Gray induces direct epigenetic effects (within the first cell cycle) in the exposed cells. ELISA-based fluorometric assays were consistent with slightly reduced global DNA methylation and hydroxymethylation, however the observed between-group differences were usually not significant. Similarly, bisulfite pyrosequencing of interspersed LINE-1 repeats and centromeric α-satellite DNA did not detect significant methylation differences between irradiated and non-irradiated cultures. Methylation of interspersed ALU repeats appeared to be slightly increased (one percentage point; p = 0.01) at 6 h after irradiation with 4 Gy. Single-cell analysis showed comparable variations in repeat methylation among individual cells in both irradiated and control cultures. Radiation-induced changes in global repeat methylation, if any, were much smaller than methylation variation between different fibroblast strains. Interestingly, α-satellite DNA methylation positively correlated with gestational age. Finally, 450K methylation arrays mainly targeting genes and CpG islands were used for global DNA methylation analysis. There were no detectable methylation differences in genic (promoter, 5' UTR, first exon, gene body, 3' UTR) and intergenic regions between irradiated and control fibroblast cultures. Although we cannot exclude minor effects, i.e. on individual CpG sites, collectively our data suggest that global DNA methylation remains rather stable in irradiated normal body cells in the early phase of DNA damage response.
KW  - DNA methylation
KW  - fibroblasts
KW  - methylation
KW  - alu elements
KW  - DNA damage
KW  - epigenetics
KW  - cancer treatment
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170895
VL  - 12
IS  - 5
ER  -