Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA125447 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Relapse is the most common cause of treatment failure in pediatric acute lymphoblastic leukemia (ALL) and is often difficult to predict. To explore the prognostic impact of recurrent DNA copy number abnormalities on relapse, we performed high-resolution genomic profiling of 34 paired diagnosis-relapse ALL samples. Recurrent lesions detected at diagnosis, including PAX5, CDKN2A, and EBF1, were frequently absent at relapse, indicating that they represent secondary events that may be absent in the relapse-prone therapy-resistant progenitor cell. In contrast, deletions and nonsense mutations in IKZF1 (IKAROS), were highly enriched and consistently preserved at the time of relapse. A targeted copy number screen in an unselected cohort of 131 precursor B-ALL cases, enrolled in the dexamethasone-based Dutch Childhood Oncology Group treatment protocol ALL9, revealed that IKZF1 deletions are significantly associated with poor relapse-free and overall survival rates. Separate analysis of ALL9-treatment subgroups revealed that non-high-risk patients with IKZF1 deletions exhibited a ~12-fold higher relative relapse rate than those without IKZF1 deletions. Consequently, IKZF1 deletion status allowed the prospective identification of 53% of the relapse-prone non-high-risk-classified patients within this subgroup and, therefore, serves as one of the strongest predictors of relapse at the time of diagnosis with high potential for future risk stratification. Affymetrix NspI 250k array data of 34 paired diagnosis and relapse samples of pediatric ALL. From 13 patients a complete remission sample was available. Four cases had 2 relapses.
2010-03-01 | GSE20353 | GEO
Project description:We studied a cohort of 221 high-risk pediatric B-progenitor ALL patients that excluded known high risk ALL subtypes (BCR-ABL1 and infant ALL), using Affymetrix single nucleotide polymorphism microarrays, gene expression profiling and candidate gene resequencing. A CNA poor outcome predictor was identified using a semi-supervised principal components approach, and tested in an independent validation cohort of 258 pediatric B-progenitor ALL cases. Over 50 regions of recurring somatically acquired CNA, with the most frequently targeted genes encoding regulators of B-lymphoid development (66.8% of cases; with PAX5 targeted in 31.7% and IKZF1 in 28.6%). A CNA classifier identified a very poor outcome subgroup in the high-risk cohort (P=4.2x10-5) and was strongly associated with the presence of deletions involving IKZF1, which encodes the early lymphoid transcription factor IKAROS. This classifier, and IKZF1 deletions, also predicted poor outcome and elevated minimal residual disease at the end of induction therapy in the validation cohort. The gene expression signature of the poor outcome group was characterized by reduced expression of B lineage specific genes, and was highly related to the expressing signature of BCR-ABL1 ALL, a known high-risk ALL subtype also characterized by a high frequency of IKZF1 deletion.Somatically acquired deletions involving IKZF1 identify a very poor outcome subgroup of pediatric ALL patients. Incorporation of molecular tests to identify IKZF1 deletion in diagnostic leukemic blasts should improve the ability to accurately risk stratify patients for appropriate therapy. Affymetrix U133A arrays were performed according to the maufacturers directions on RNA extracted from cryopreserved diagnostic bone marrow or peripheral blood samples. Samples with less than 80% blasts were flow sorted prior to RNA extraction Experiment Overall Design: One hundred seventy five pediatric B-progenitor ALL samples were studied using either Affymetrix U133A
2008-10-26 | E-GEOD-12995 | biostudies-arrayexpress
Project description:We studied a cohort of 221 high-risk pediatric B-progenitor ALL patients that excluded known high risk ALL subtypes (BCR-ABL1 and infant ALL), using Affymetrix single nucleotide polymorphism microarrays, gene expression profiling and candidate gene resequencing. A CNA poor outcome predictor was identified using a semi-supervised principal components approach, and tested in an independent validation cohort of 258 pediatric B-progenitor ALL cases. Over 50 regions of recurring somatically acquired CNA, with the most frequently targeted genes encoding regulators of B-lymphoid development (66.8% of cases; with PAX5 targeted in 31.7% and IKZF1 in 28.6%). A CNA classifier identified a very poor outcome subgroup in the high-risk cohort (P=4.2x10-5) and was strongly associated with the presence of deletions involving IKZF1, which encodes the early lymphoid transcription factor IKAROS. This classifier, and IKZF1 deletions, also predicted poor outcome and elevated minimal residual disease at the end of induction therapy in the validation cohort. The gene expression signature of the poor outcome group was characterized by reduced expression of B lineage specific genes, and was highly related to the expressing signature of BCR-ABL1 ALL, a known high-risk ALL subtype also characterized by a high frequency of IKZF1 deletion.Somatically acquired deletions involving IKZF1 identify a very poor outcome subgroup of pediatric ALL patients. Incorporation of molecular tests to identify IKZF1 deletion in diagnostic leukemic blasts should improve the ability to accurately risk stratify patients for appropriate therapy. Affymetrix U133A arrays were performed according to the maufacturers directions on RNA extracted from cryopreserved diagnostic bone marrow or peripheral blood samples. Samples with less than 80% blasts were flow sorted prior to RNA extraction
2008-10-02 | GSE12995 | GEO
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
| S-EPMC2531291 | biostudies-literature
Project description:RNA extracted at 240min. Samples are rRNA depleted. Expression measurement of Homo sapiens genes.
2019-07-31 | GSE114179 | GEO
Project description:As the evolution of miRNA genes has been found to be one of the important factors in formation of the modern type of man, we performed a comparative analysis of the evolution of miRNA genes in two archaic hominines, Homo sapiens neanderthalensis and Homo sapiens denisova, and elucidated the expression of their target mRNAs in bain.A comparative analysis of the genomes of primates, including species in the genus Homo, identified a group of miRNA genes having fixed substitutions with important implications for the evolution of Homo sapiens neanderthalensis and Homo sapiens denisova. The mRNAs targeted by miRNAs with mutations specific for Homo sapiens denisova exhibited enhanced expression during postnatal brain development in modern humans. By contrast, the expression of mRNAs targeted by miRNAs bearing variations specific for Homo sapiens neanderthalensis was shown to be enhanced in prenatal brain development.Our results highlight the importance of changes in miRNA gene sequences in the course of Homo sapiens denisova and Homo sapiens neanderthalensis evolution. The genetic alterations of miRNAs regulating the spatiotemporal expression of multiple genes in the prenatal and postnatal brain may contribute to the progressive evolution of brain function, which is consistent with the observations of fine technical and typological properties of tools and decorative items reported from archaeological Denisovan sites. The data also suggest that differential spatial-temporal regulation of gene products promoted by the subspecies-specific mutations in the miRNA genes might have occurred in the brains of Homo sapiens denisova and Homo sapiens neanderthalensis, potentially contributing to the cultural differences between these two archaic hominines.
| S-EPMC4686780 | biostudies-literature
Project description:PurposeWe investigated the evidence of recent positive selection in the human phototransduction system at single nucleotide polymorphism (SNP) and gene level.MethodsSNP genotyping data from the International HapMap Project for European, Eastern Asian, and African populations was used to discover differences in haplotype length and allele frequency between these populations. Numeric selection metrics were computed for each SNP and aggregated into gene-level metrics to measure evidence of recent positive selection. The level of recent positive selection in phototransduction genes was evaluated and compared to a set of genes shown previously to be under recent selection, and a set of highly conserved genes as positive and negative controls, respectively.ResultsSix of 20 phototransduction genes evaluated had gene-level selection metrics above the 90th percentile: RGS9, GNB1, RHO, PDE6G, GNAT1, and SLC24A1. The selection signal across these genes was found to be of similar magnitude to the positive control genes and much greater than the negative control genes.ConclusionsThere is evidence for selective pressure in the genes involved in retinal phototransduction, and traces of this selective pressure can be demonstrated using SNP-level and gene-level metrics of allelic variation. We hypothesize that the selective pressure on these genes was related to their role in low light vision and retinal adaptation to ambient light changes. Uncovering the underlying genetics of evolutionary adaptations in phototransduction not only allows greater understanding of vision and visual diseases, but also the development of patient-specific diagnostic and intervention strategies.
| S-EPMC3743458 | biostudies-literature
Project description:Cortical thickness has been investigated since the beginning of the 20th century, but we do not know how similar the cortical thickness profiles among humans are. In this study, the local similarity of cortical thickness profiles was investigated using sliding window methods. Here, we show that approximately 5% of the cortical thickness profiles are similarly expressed among humans while 45% of the cortical thickness profiles show a high level of heterogeneity. Therefore, heterogeneity is the rule, not the exception. Cortical thickness profiles of somatosensory homunculi and the anterior insula are consistent among humans, while the cortical thickness profiles of the motor homunculus are more variable. Cortical thickness profiles of homunculi that code for muscle position and skin stimulation are highly similar among humans despite large differences in sex, education, and age. This finding suggests that the structure of these cortices remains well preserved over a lifetime. Our observations possibly relativize opinions on cortical plasticity.
| S-EPMC5738339 | biostudies-literature
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
2010-09-25 | GSE24338 | GEO
Project description:There is a distinct signature of differentially expressed probes from diagnosis to relapse Gene expression profiles of pediatric patients with B-precursor ALL were compared to at 2 time points, diagnosis and relapse. The overall design was a comparison of gene expression at diagnosis and relapse within individual patients. A subset analysis (comparing diagnosis to relapse expression within individuals), was done for early relapse (less than 36 months) cases only and late relapse (greater than 36 months) cases only.
2011-09-23 | E-GEOD-28460 | biostudies-arrayexpress