Background: 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.
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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 SamplesMesenchymal stromal cells (MSCs) derived from the BM of healthy donors (dMSCs) and myeloma patients (pMSCs) were co-cultured with the model myeloma cell line - MM.1S -, and the gene expression profile of MSCs induced by this interaction was analyzed using high density oligonucleotide microarrays. Deregulated genes in co-culture common to both d/pMSCs revealed functional involvement in tumor microenvironment cross-talk, myeloma growth induction and drug resistance, angiogenesis and signals for osteoclast activation and inhibition of osteoblasts. Additional genes induced by co-culture were exclusively deregulated in pMSCs and were predominantly associated to RNA processing, the ubiquitine-proteasome pathway, regulation of cell cycle and Wnt signaling.
Transcriptomic profile induced in bone marrow mesenchymal stromal cells after interaction with multiple myeloma cells: implications in myeloma progression and myeloma bone disease.
Specimen part
View SamplesLymphatic endothelial cells were grown under normoxia, hypoxia (1% 0xygen) and conditioned medio from NSLCN growth under normoxia or hypoxia. Gene expression was measured and comparition between samples performed
Hypoxia alters the adhesive properties of lymphatic endothelial cells. A transcriptional and functional study.
No sample metadata fields
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 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 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 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 SamplesAlthough new therapies have doubled the survival of multiple myeloma (MM) patients, this remains an incurable disease. It has been postulated that the so-called MM Cancer Stem Cells (MM-CSC) would be responsible for tumor initiation and relapse but their unequivocal identification remains unclear. Here, we investigated in a panel of MM cell lines the presence of CD20+ cells harboring a MM-CSC phenotype. Among the multiple cell lines investigated, only a small population of CD20dim+ cells (0.3%) in the RPMI-8226 cell line was found. CD20dim+ RPMI-8226 cells expressed the plasma cell markers CD38 and CD138 and were CD19-CD27-. Additionally, CD20dim+ RPMI-8226 cells did not exhibit stem-cell markers as shown by gene expression profiling and the aldehyde dehydrogenase (ALDH) assay. Moreover, we demonstrated that CD20dim+ RPMI-8226 cells are not essential for CB17-SCID mice engraftment and show lower self-renewal potential than the CD20- RPMI-8226 cells. These results do not support CD20+ expression for the identification of MM-CSC.
CD20 positive cells are undetectable in the majority of multiple myeloma cell lines and are not associated with a cancer stem cell phenotype.
No sample metadata fields
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
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