Systemic lupus erythematosous (SLE) is an autoimmune disease with an important clinical and biological heterogeneity. B lymphocytes appear central to the development of SLE which is characterized by the production of a large variety of autoantibodies and hypergammaglobulinemia. In mice, immature B cells from spontaneous lupus prone animals are able to produce autoantibodies when transferred into immunodeficient mice, strongly suggesting the existence of intrinsic B cell defects during lupus. In order to approach these defects in humans, we compared the peripheral B cell transcriptomes of quiescent lupus patients to normal B cell transcriptomes.
B cell signature during inactive systemic lupus is heterogeneous: toward a biological dissection of lupus.
Specimen part, Disease, Disease stage, Subject
View SamplesThe epidermal specific ablation of Trp53 gene leads to the spontaneous development of aggressive tumors in mice through a process that is accelerated by the simultaneous ablation of Rb gene. Since alterations of p53-dependent pathway are common hallmarks of aggressive, poor prognostic human cancers, these mouse models can recapitulate the molecular features of some of these human malignancies. To evaluate this possibility, gene expression microarray analysis was performed in mouse samples. The mouse tumors display increased expression of cell cycle and chromosomal instability associated genes. Remarkably, they are also enriched in human embryonic stem cell gene signatures, a characteristic feature of human aggressive tumors. Using cross-species comparison and meta-analytical approaches, we also observed that spontaneous mouse tumors display robust similarities with gene expression profiles of human tumors bearing mutated TP53, or displaying poor prognostic outcome, from multiple body tissues. We have obtained a 20-gene signature whose genes are overexpressed in mouse tumors and can identify human tumors with poor outcome from breast cancer, astrocytoma and multiple myeloma. This signature was consistently overexpressed in additional mouse tumors using microarray analysis. Two of the genes of this signature, AURKA and UBE2C, were validated in human breast and cervical cancer as potential biomarkers of malignancy. Our analyses demonstrate that these mouse models are promising preclinical tools aimed to search for malignancy biomarkers and to test targeted therapies of prospective use in human aggressive tumors and/or with p53 mutation or inactivation.
Gene expression profiling of mouse p53-deficient epidermal carcinoma defines molecular determinants of human cancer malignancy.
Age, Specimen part
View SamplesHuman cell line HCT116 incubated with Myxothiazol for 5 or 17 hours
A sustained deficiency of mitochondrial respiratory complex III induces an apoptotic cell death through the p53-mediated inhibition of pro-survival activities of the activating transcription factor 4.
No sample metadata fields
View SamplesBackground: Differences in breast cancer outcomes according to race/ethnicity have been reported. Hispanic/Latino (H/L) populations are a genetically admixed and heterogeneous group, with variable fractions of European, Indigenous American and African ancestries. Some studies suggest that breast cancer-specific mortality is higher in U.S. Hispanic/Latinas compared to non-Hispanic Whites (NHW) even after adjustment for socioeconomic status and education. The molecular profile of breast cancer has been widely described in NHWs but equivalent knowledge is lacking in Hispanic/Latinas. We have previously reported that the most prevalent breast cancer intrinsic subtype in Colombian H/L women was Luminal B as defined by surrogate St. Gallen 2013 criteria. In this study we explored ancestry-associated differences in molecular profiles of Luminal B tumors among these highly admixed women. Methods: We performed whole-transcriptome RNA-seq analysis in 42 Luminal tumors (21 Luminal A and 21 Luminal B) from Colombian women. Genetic ancestry was estimated from a panel of 80 ancestry-informative markers (AIM). We categorized patients according to Luminal subtype and to the proportion of European and Indigenous American ancestry and performed differential expression analysis comparing Luminal B against Luminal A tumors according to the assigned ancestry groups. Results: We found 5 genes potentially modulated by genetic ancestry: ERBB2 (Fold Change = 2.367, padj < 0.01), GRB7 (Fold Change = 2.327, padj < 0.01), GSDMB (Fold Change = 1.723, padj < 0.01, MIEN1 (Fold Change = 2.195, padj < 0.01 and ONECUT2 (Fold Change = 2.204, padj < 0.01). In the replication set we found a statistical significant association between European ancestry fraction and the expression levels of ERBB2 (p = 0.02, B = 2.49) and ONECUT2 (p = 0.04, B = -4.87). We also observed statistical significant associations for ERBB2 expression with Indigenous American ancestry (p < 0.001, B = 3.82). This association was not biased by the distribution of HER2+ tumors among the groups analyzed. Conclusions: Our results suggest that genetic ancestry in Hispanic/Latina women might modify ERBB2 gene expression in Luminal tumors. Further analyses are needed to confirm these findings and explore their prognostic value. Overall design: RNA profile of 42 luminal breast cancer tumors (21 luminal A and 21 luminal B) from Colombian patients
Ancestry as a potential modifier of gene expression in breast tumors from Colombian women.
No sample metadata fields
View SamplesHuman umbilical cord Whartons jelly stem cells (WHJSC) are gaining attention as a possible clinical source of mesenchymal stem cells for use in cell therapy and tissue engineering due to their high accessibility, expansion potential and plasticity. However, the cell viability changes that are associated to sequential cell passage of these cells are not known. In this analysis, we have identified the gene expression changes that are associated to cell passage in WHJSC.
Evaluation of the cell viability of human Wharton's jelly stem cells for use in cell therapy.
Specimen part
View SamplesCompare the behaviour of two populations of non-hematopoetic stem cells (MSC and MAPC) isolated from human bone marrow. The effect of culture conditions on the behaviour of MSC was also characterised by isolating MSC and then culturing the cells for 96h in MAPC growth conditions
Validation of COL11A1/procollagen 11A1 expression in TGF-β1-activated immortalised human mesenchymal cells and in stromal cells of human colon adenocarcinoma.
Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrative analysis of DNA copy number, DNA methylation and gene expression in multiple myeloma reveals alterations related to relapse.
Sex, Age, Specimen part
View SamplesMultiple myeloma (MM) remains incurable despite the introduction of novel agents and a relapsing course is observed in the majority of patients. Although the development of genomic technologies has greatly improved our understanding of MM pathogenesis, the mechanisms underlying relapse have been less investigated. In this study, an integrative analysis of DNA copy number, DNA methylation and gene expression was conducted in matched diagnosis and relapse samples from 17 MM patients. Overall, the acquisition of abnormalities at relapse was much more frequent than the lost of lesions present at diagnosis, and DNA losses were significantly more frequent at relapse than in diagnosis samples. Interestingly, copy number abnormalities involving more than 100 Mb of DNA at relapse significantly impact the gene expression of these samples, provoking a particular deregulation of IL-8 pathway. On the contrary, no relevant modifications of gene expression were observed in those samples with less than 100 Mb affected by chromosomal changes. Although different statistical approaches were used to uncover genes whose abnormal expression at relapse was regulated by DNA methylation, only two genes significantly deregulated in relapse samples (SORL1 and GLT1D1) showed a negative methylation-expression correlation. A deeper analysis demonstrated that DNA methylation was involved in regulation of SORL1 expression in MM. Finally, relevant changes in gene expression observed in relapse samples, such us downregulation of CD27 and P2RY8, were not apparently preceded by alterations in corresponding DNA. Taken together, these results showed that genomic heterogeneity, both at the DNA and RNA level, is a hallmark of MM transition from diagnosis to relapse.
Integrative analysis of DNA copy number, DNA methylation and gene expression in multiple myeloma reveals alterations related to relapse.
Sex, Specimen part
View SamplesDespite recent advances in the treatment of multiple myeloma (MM), it remains an incurable disease potentially due to the presence of resistant myeloma cancer stem cells (MM-CSC). Although the presence of clonogenic cells in MM was described more than 30 years ago, the phenotype of MM-CSC is still a matter of debate, especially with respect to the expression of syndecan- 1 (CD138). Here, we demonstrate the presence of two subpopulations - CD138++ (95-99%) and CD138low (1-5%) - in eight MM cell lines. To find out possible stem-cell-like features, we have phenotypically, genomic and functionally characterized the two subpopulations. Our results show that the minor CD138low subpopulation is morphologically identical to the CD138++ fraction and does not represent a more immature B-cell compartment (with lack of CD19, CD20 and CD27 surface expression). Moreover, both subpopulations have similar gene expression and genomic profiles. Importantly, both CD138++ and CD138low subpopulations have similar sensitivity to bortezomib, melphalan and doxorubicin. Finally, serial engraftment in SCID mice shows that CD138++ as well as CD138low cells have self-renewal potential and they are also phenotypically interconvertible. Overall, our results differ from previously published data which attribute a B-cell phenotype to MM-CSC and urge the need to explore more reliable markers to discriminate true clonogenic myeloma cells.
Phenotypic, genomic and functional characterization reveals no differences between CD138++ and CD138low subpopulations in multiple myeloma cell lines.
Disease, Cell line
View SamplesHeart formation requires the fusion of bilateral cardiomyocyte populations as they move toward the embryonic midline. The bHLH transcription factor Hand2 is essential for cardiac fusion; however, the effector genes that execute this function of Hand2 are unknown. Here, we provide the first evidence for a downstream component of the Hand2 pathway that mediates cardiac morphogenesis. Although hand2 is expressed in cardiomyocytes, mosaic analysis demonstrates that hand2 plays a non-autonomous role in regulating cardiomyocyte movement. Gene expression profiles reveal heightened expression of fibronectin 1 (fn1) in hand2 mutant embryos. Reciprocally, overexpression of hand2 leads to decreased Fibronectin levels. Furthermore, reduction of fn1 function enables rescue of cardiac fusion in hand2 mutants: bilateral cardiomyocyte populations merge and exhibit improved tissue architecture, albeit without major changes in apicobasal polarity. Together, our data provide a novel example of a tissue creating a favorable environment for its morphogenesis: the Hand2 pathway establishes an appropriate environment for cardiac fusion through negative modulation of Fn1 levels.
Hand2 ensures an appropriate environment for cardiac fusion by limiting Fibronectin function.
Specimen part
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