We retrospectively analyzed AML patients enrolled in the AIEOP since 2000, 42 patients with 11q23 rearrangement were analyzed by gene expression profile
MLL partner genes drive distinct gene expression profiles and genomic alterations in pediatric acute myeloid leukemia: an AIEOP study.
Disease, Disease stage
View SamplesWe examined if the minimal residual disease (MRD) and the Allelic Ratio (AR) of FLT3 internal tandem duplication (ITD) mutated patients may be prognostic factors. We correlated these parameters both with event free survival (EFS), with incidence of relapse and with gene expression profile (GEP). GEP showed that patients with high-ITD-AR or persistent MRD had different expression profiles. Results indicated that the ITD-AR levels and the MRD after I induction course are associated with transcriptional oncogenic profiles, which highlight differences in epigenetic control that may explain the variability in outcome among FLT3-ITD patients
Characterization of children with FLT3-ITD acute myeloid leukemia: a report from the AIEOP AML-2002 study group.
Specimen part, Disease
View SamplesSeventeen T-ALL patients out of 120 (14.2%) presented CRLF2 expression 5 times higher than the median (CRLF2-high) with a significantly inferior 5-y EFS and an increased CIR compared to CRLF2-low patients.GEP of 15 T-ALL patients with (CRLF2-high) were compared to 15 CRLF2-low patients. GSEA identified cell cycle deregulating gene sets.
CRLF2 over-expression is a poor prognostic marker in children with high risk T-cell acute lymphoblastic leukemia.
Disease
View SamplesEstrogen receptor-{alpha} (ER{alpha}) and its ligand estradiol play critical roles in breast cancer growth and are important therapeutic targets for this disease. Using chromatin immunoprecipitation (ChIP)-on-chip, ligand-bound ER{alpha} was recently found to function as a master transcriptional regulator via binding to many cis-acting sites genome-wide. Here, we used an alternative technology (ChIP cloning) and identified 94 ER{alpha} target loci in breast cancer cells. The ER{alpha}-binding sites contained both classic estrogen response elements and nonclassic binding sequences, showed specific transcriptional activity in reporter gene assay, and interacted with the key transcriptional regulators, including RNA polymerase II and nuclear receptor coactivator-3. The great majority of the binding sites were located in either introns or far distant to coding regions of genes. Forty-three percent of the genes that lie within 50 kb to an ER{alpha}-binding site were regulated by estradiol. Most of these genes are novel estradiol targets encoding receptors, signaling messengers, and ion binders/transporters. mRNA profiling in estradiol-treated breast cancer cell lines and tissues revealed that these genes are highly ER{alpha} responsive both in vitro and in vivo. Among estradiol-induced genes, Wnt11 was found to increase cell survival by significantly reducing apoptosis in breast cancer cells. Taken together, we showed novel genomic binding sites of ER{alpha} that regulate a novel set of genes in response to estradiol in breast cancer. Our findings suggest that at least a subset of these genes, including Wnt11, may play important in vivo and in vitro biological roles in breast cancer.
Novel estrogen receptor-alpha binding sites and estradiol target genes identified by chromatin immunoprecipitation cloning in breast cancer.
No sample metadata fields
View SamplesGonadal sex determining (GSD) genes that initiate fetal ovarian and testicular development and differentiation are expressed in the cells of the urogenital ridge that differentiate as somatic support cells (SSCs), i.e., granulosa cells of the ovary and Sertoli cells of the testis. To identify potential new mammalian GSD genes, we analyzed the gene expression differences between XX and XY SSCs cells isolated from the gonads of embryonic day (E) 13 mouse fetuses carrying an EGFP reporter transgene expressed specifically in SSCs. In addition, genome wide expression differences between XX and XY E13 whole gonads were examined. Newly identified differentially expressed transcripts are potential GSD genes involved in unexplained human sex reversal cases.
Transcriptional profile of mouse pre-granulosa and Sertoli cells isolated from early-differentiated fetal gonads.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Genome-wide promoter analysis of the SOX4 transcriptional network in prostate cancer cells.
No sample metadata fields
View SamplesSOX4 is a critical developmental transcription factor in vertebrates and is required for precise differentiation and proliferation in multiple tissues. In addition, SOX4 is overexpressed in many human malignancies, but the precise role of SOX4 in cancer progression is not well understood. Here we have performed an expression profiling experiment of LNCaP cells either overexpressing SOX4 or GFP to identify SOX4 target genes.
Genome-wide promoter analysis of the SOX4 transcriptional network in prostate cancer cells.
No sample metadata fields
View SamplesSOX4 is a critical developmental transcription factor in vertebrates and is required for precise differentiation and proliferation in multiple tissues. In addition, SOX4 is overexpressed in many human malignancies, but the precise role of SOX4 in cancer progression is not well understood. Here we have either eliminated SOX4 using siRNA or overexpressed a SOX4 cDNA and compared the gene expression patterns against control GFP transfections to identify SOX4 target genes.
Genome-wide promoter analysis of the SOX4 transcriptional network in prostate cancer cells.
No sample metadata fields
View SamplesAcute myeloid leukemia (AML) is a heterogeneous disease and AML with normal karyotype (AML-NK) is categorized as an intermediate-risk group. Over the past years molecular analyses successfully identified biomarkers that will further allow to dissecting clinically meaningful subgroups in this disease. Thus far, somatic mutations were identified which elucidate the disturbance of cellular growth, proliferation, and differentiation processes in hematopoietic progenitor cells. In AML-NK, acquired gene mutations with prognostic relevance were identified for FLT3, CEBPA, and NPM1. FLT3-ITD mutations were associated with short relapse-free and overall survival, while mutations in CEBPA or NPM1 (without concomitant FLT3-ITD) had a more favorable outcome.
Quantitative comparison of microarray experiments with published leukemia related gene expression signatures.
Sex, Age, Disease, Disease stage
View SamplesAlternative mRNA splicing represents an effective mechanism of regulating gene function and is a key element to increase the coding capacity of the human genome. Today, an increasing number of reports illustrates that aberrant splicing events are common and functionally important for cancer development. However, more comprehensive analyses are warranted to get novel insights into the biology underlying malignancies like e.g. acute myeloid leukemia (AML). Here, we performed a genome-wide screening of splicing events in AML using an exon microarray platform. We analyzed complex karyotype and core binding factor (CBF) AML cases (n=64) in order to evaluate the ability to detect alternative splicing events distinguishing distinct leukemia subgroups. Testing different commercial and open source software tools to compare the respective AML subgroups, we could identify a large number of potentially alternatively spliced transcripts with a certain overlap of the different approaches. Selected candidates were further investigated by PCR and sequence analysis: out of 24 candidate genes studied, we could confirm alternative splice forms in 8 genes of potential pathogenic relevance, such as PRMT1 regulating transcription through histone methylation and participating in DNA damage response, and PTPN6, which encodes for a negative regulator of cell cycle control and apoptosis. In summary, this first large Exon microarray based study demonstrates that transcriptome splicing analysis in AML is feasible but challenging, in particular with regard to the currently available software solutions. Nevertheless, our results show that alternatively spliced candidate genes can be detected, and we provide a guide how to approach such analyses.
A robust estimation of exon expression to identify alternative spliced genes applied to human tissues and cancer samples.
Specimen part, Disease, Disease stage
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