The clinical impact of aberrant CEBPA promoter methylation (PM) in AML is controversial discussed. The aim of this study was to clarify the significance of aberrant CEBPA PM with regard to clinical features in a cohort of 572 de novo AML with wildtype CEBPA and normal karyotype. The distal promoter was methylated in 54/572 cases (9.41%) whereas proximal PM was never detected. Methylation of the core promoter was detected in only 8 of 326 cases (2.45%) and thus seems to be a rare event in AML. There was no correlation between CEBPA distal PM, age, sex, white blood cell (WBC) count or Hb levels at diagnosis. We also were not able to detect a significant correlation between the presence of CEBPA distal PM and molecular mutations such as FLT3-ITD, NPM1, AML1, MLL-PTD and IDH1. Solely the frequency of IDH2R140 mutations was significantly reduced in CEBPA distal PM positive compared to CEBPA distal PM negative cases (p=0.01). Furthermore, analysis of CEBPA mRNA expression level revealed no difference between CEBPA distal PM positive and CEBPA distal PM negative cases, suggesting that CEBPA distal PM has no influence on CEBPA expression. CEBPA distal PM did not show impact on overall survival (OS), event free survival (EFS) or incidence of relapse. Also when other mutations were taken into regard no prognostic impact of CEBPA distal PM could be shown. In contrast, a distinct expression profile of CEBPA distal PM positive cases compared to CEBPA mutated and CEBPA distal PM negative cases was observed. In addition, a significantly higher frequency of CEBPA distal PM was detected in RUNX1-RUNX1T1 positive AML compared to the CEBPA witdtype cases. We conclude that the presence of aberrant CEBPA PM has no clinical relevance and is therefore a negligible prognostic marker in de novo AML with normal karyotype.
Frequency and prognostic impact of CEBPA proximal, distal and core promoter methylation in normal karyotype AML: a study on 623 cases.
Disease
View SamplesExpression analysis of mature Arabidopsis trichomes in Col-0 and two mutants, triptychon (try-JC) and glabra3 (gl3-3)
Transcriptional profiling of mature Arabidopsis trichomes reveals that NOECK encodes the MIXTA-like transcriptional regulator MYB106.
Specimen part
View SamplesFull Title: Multilineage Dysplasia (MLD) in AML correlates with MDS-related cytogenetic abnormalities and a prior history of MDS or MDS/MPN but has no independent prognostic relevance: A comparison of 408 cases classified as AML not otherwise specified or AML with myelodysplasia-related changes
Multilineage dysplasia (MLD) in acute myeloid leukemia (AML) correlates with MDS-related cytogenetic abnormalities and a prior history of MDS or MDS/MPN but has no independent prognostic relevance: a comparison of 408 cases classified as "AML not otherwise specified" (AML-NOS) or "AML with myelodysplasia-related changes" (AML-MRC).
No sample metadata fields
View SamplesBy WHO 2008, CEBPA-mutated AML became a provisional subentity, but it remains to be clarified how CEBPAmut AML with multilineage dysplasia (MLD; 50% dysplastic cells in 2-3 lineages) but no other MDS-related feature should be classified. We investigated 108 CEBPAmut AML (15.7-87.6 years) for the impact of MLD and genetic features. MLD-positive patients differed from MLD-negative only by lower mean WBC counts (p=0.004), but not by other blood values, biologic characteristics, cytogenetic risk profiles, or additional molecular markers (NPM1mut, FLT3-ITD/TKD, RUNX1, MLL-PTD, IDH1/2). Biallelic CEBPAmut differed from wild-type-cases by differential expression of 213 genes, but did not differ significantly between MLD-positive/-negative patients. Survival outcomes were improved for females and those <60 years, intermediate versus adverse karyotypes (p=0.021), and for biallelic versus monoallelic/homozygous CEBPAmut (p=0.060) in case of FLT3-ITD-negativity. In contrast, 2-year OS (MLD+: 56.5%; MLD-: 65.5%) and 2-year EFS (MLD+: 13.8 months; MLD-: 16.3 months) did not differ significantly between MLD-positive/-negative patients. By univariable Cox regression analysis, gender, age, WBC count and MRC-cytogenetic risk category only were prognostically relevant for OS, while MLD was irrelevant. Therefore, CEBPAmut AML patients should be characterized only according to mut-status, cytogenetic risk groups, or additional mutations, whereas dysplasia is not relevant for this subtype.
Multilineage dysplasia does not influence prognosis in CEBPA-mutated AML, supporting the WHO proposal to classify these patients as a unique entity.
Specimen part, Disease, Disease stage
View SamplesInterest focuses on genes encoding histone demethylases in hematologic malignancies, such as EZH2 (enhancer of zeste homolog 2). EZH2 mutations were recurrently observed in lymphomas and chronic myeloid malignancies, but data in acute leukemias are limited. We investigated 13 PICALM-MLLT10 (=CALM-AF10) rearranged acute leukemia predominantly of T-lineage (7 m/6 f; 653 years) by deep-sequencing for EZH2mut and identified 3 (23%) EZH2mut carriers: one splice site mutation in exon 14, while two patients had missense mutations in the D1 region of exon 5 which interacts with different DNA methyltransferase genes (but no DNMT3Amut was detected in the 13 PICALM-MLLT10-positive patients).
EZH2 mutations and their association with PICALM-MLLT10 positive acute leukaemia.
Specimen part, Disease, Disease stage
View SamplesEstrogen has vascular protective effects in premenopausal women and in women under 60 receiving hormone replacement therapy. However, estrogen also increases risks of breast and uterine cancers and of venous thromboses linked to upregulation of coagulation factors in the liver. In mouse models, the vasoprotective effects of estrogen are mediated by the estrogen receptor alpha (ERa) transcription factor. Here, through next generation sequencing approaches, we show that almost all of the genes regulated by 17-b-estradiol (E2) differ between mouse aorta and mouse liver, and that this is associated with a distinct genomewide distribution of ERa on chromatin. Bioinformatic analysis of E2-regulated promoters and ERa binding site sequences identify several transcription factors that may determine the tissue specificity of ERa binding and E2-regulated genes, including the enrichment of NFkB, AML1 and AP-1 sites in the promoters of E2 downregulated inflammatory genes in aorta but not liver. The possible vascular-specific functions of these factors suggests ways in which the protective effects of estrogen could be promoted in the vasculature without incurring negative effects in other tissues. Our results also highlight the likely importance of rapid signaling of membrane-associated ERa to cellular kinases (altering the activities of transcription factors other than ER itself) in determining tissue specific transcriptional responses to estrogen. Overall design: The aortas or liver fragments of wild-type C57/BL6 mice were incubated ex vivo with 10nM E2 or ethanol vehicle for 4 hours before harvesting for RNA collection. Each condition was performed with two biological replicates, and each replicate contained aortas or liver fragments from 4 mice.
Research resource: Aorta- and liver-specific ERα-binding patterns and gene regulation by estrogen.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MicroRNA-Offset RNA Alters Gene Expression and Cell Proliferation.
Specimen part, Treatment
View SamplesMicroRNA-offset RNAs (moRs) were first identified in simple chordates and subsequently in mouse and human cells by deep sequencing of short RNAs. MoRs are derived from sequences located immediately adjacent to microRNAs (miRs) in the primary miR (pri-miR). Currently moRs are considered to be simply a by-product of miR biosynthesis that lack biological activity. Here we show for the first time that a moR is biologically active. We now demonstrate that endogenous and over-expressed moR-21 significantly alters gene expression and inhibits the proliferation of vascular smooth muscle cells (VSMC). We report that the seed region of moR-21 as well as the seed match region in the target gene 3'UTR are indispensable for moR-21-mediated gene down-regulation. We further demonstrated that moR-21-mediated gene repression is Argonaute 2 (Ago2) dependent. In addition, we find that miR-21 and moR-21 may regulate different genes in a given pathway and can oppose each other in regulating certain genes. Taken together, these findings provide the first evidence that microRNA offset RNA regulates gene expression and is biologically active.
MicroRNA-Offset RNA Alters Gene Expression and Cell Proliferation.
Specimen part, Treatment
View SamplesAcute myeloid leukemia (AML) with CEBPA mutations is determined as provisional entity in the current WHO. A difference in clinical outcome between single- (sm) and double-mutated (dm) cases has been reported, whereupon dm cases were shown to be associated with longer overall survival (OS). The occurrence and prognostic impact of concomitant molecular mutations in addition to CEBPAdm has not been assessed until now. Here, we investigated a cohort of 95 AML CEBPAdm cases for concomitant mutations. TET2 was found to be the most frequent mutation (32/94, 34.0%), followed by GATA2 (20/95, 21.0%), WT1 (13/95, 13.7%), DNMT3A (9/94, 9.6%), ASXL1 (9/95, 9.5%), NRAS (8/95, 8.4%), KRAS (3/94, 3.2%), IDH1/2 (6/95, 6.3%), FLT3-ITD (6/95, 6.3%), FLT3-TKD (2/95, 2.1%), NPM1 (2/95, 2.1%), and RUNX1 (1/94). No mutation was detected in MLL-PTD and TP53. With respect to prognostic impact, we observed that those cases harboring additional mutations in TET2 showed significant worse survival than wild-type cases (P=0.035), whereas GATA2 mutated cases showed improved survival (P=0.032). Further, using gene expression microarray analysis we identified no clear different clustering within the CEBPAdm cases with the distinct concomitant mutated genes. In conclusion, we demonstrated that 76.8% of CEBPAdm cases harbored additional alterations in other molecular markers and that CEBPA is a suitable MRD marker to control therapy.
CEBPA double-mutated acute myeloid leukaemia harbours concomitant molecular mutations in 76·8% of cases with TET2 and GATA2 alterations impacting prognosis.
Disease, Disease stage
View SamplesMicroarrays were used to determine relative global gene expression changes in WT and BRCA1-mutation carrier breast epithelium as well as tumors created from WT and BRCA1-mutation carrier breast epithelial cells.
Genetic predisposition directs breast cancer phenotype by dictating progenitor cell fate.
Specimen part, Disease, Disease stage
View Samples