Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA98943 | ENA |
REPOSITORIES: ENA
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Project description:Goal of this study was to investigate gene expression profiling across different molecular subtypes of breast cancers, such as Estrogen Receptor (ER) positive, HER2 amplified, Triple negative Basal A, Triple negative Basal B.
2022-08-29 | GSE212143 | GEO
Project description:Expression profiling studies have classified breast carcinomas into luminal, normal breast-like, HER2 expressing and basal-like groups, with the latter two associated with poor outcomes. This study's objectives were to define an immunohistochemical profile that identifies basal-like tumors, to identify the presence of potential drug targets, and to determine the prognostic significance of the basal-like immunophenotype in a large series with long-term follow-up. On a panel of 21 breast tumors with basal-like expression profiles, we determined that this subtype was immunohistochemically negative for estrogen receptor and HER2, but positive for basal cytokeratins, HER1 and/or c-KIT. Using breast carcinoma tissue microarrays representing 930 patients with 17.4 years mean follow-up, basal cytokeratin expression was associated with decreased disease-specific survival. HER1 expression was observed in 54% of cases positive for basal cytokeratins (vs. 11% of negative cases) and was associated with poor survival independent of nodal status and size. c-KIT expression was more common in basal-like tumors than in other breast cancers, but did not influence prognosis. A panel of four antibodies (ER, HER1, HER2, and cytokeratin 5/6) can accurately identify basal-like tumors and suggests candidate drugs for therapies targeting HER1 or c-KIT.
2006-09-15 | E-SMDB-2863 | biostudies-arrayexpress
Project description:Long non-coding RNAs (lncRNAs) play key roles in the regulation of breast cancer initiation and progression. LncRNAs are differentially expressed in breast cancer subtypes. Basal-like breast cancers are generally poorly differentiated tumors, are enriched in embryonic stem cell signatures, lack expression of estrogen receptor, progesterone receptor, and HER2 (triple negative breast cancer, TNBC), and show activation of proliferation-associated factors. We hypothesized that lncRNAs are key regulators of basal breast cancers. Using The Cancer Genome Atlas we identified lncRNAs that are overexpressed in basal tumors compared to other breast cancer subtypes and expressed in at least 10% of patients. Remarkably, we identified lncRNAs whose expression correlated with patient prognosis. We then evaluated the function of a subset of lncRNA candidates in the oncogenic process in vitro. Here, we report the identification and characterization of the chromatin-associated lncRNA, RP11-19E11.1, which is up-regulated in 40% of basal primary breast cancers. Gene set enrichment analysis in primary tumors and in cell lines uncovered a correlation between RP11-19E11.1 expression level and the E2F oncogenic pathway. We show that this lncRNA is chromatin-associated and an E2F1 target, and its expression is necessary for cancer cell proliferation and survival. Finally, we used lncRNA expression levels as a tool for drug discovery in vitro, identifying Protein Kinase C (PKC) as a potential therapeutic target for a subset of basal-like breast cancers. Our findings suggest lncRNA overexpression is clinically relevant. Understanding deregulated lncRNA expression in basal-like breast cancer may lead to potential prognostic and therapeutic applications.
2019-12-11 | GSE138606 | GEO
Project description:Breast cancer is a heterogeneous disease comprised of at least five major subtypes. Luminal subtype tumors confer a more favourable patient prognosis, which is in part, attributed to the Estrogen Receptor-alpha (ER) positivity and anti-hormone responsiveness of these tumors. Expression of the forkhead box transcription factor, FOXA1, also correlates with the luminal subtype and patient survival, but is present in a subset of ER-negative tumors. Similarly, FOXA1 is consistently expressed in luminal breast cancer cell lines even in the absence of ER. In contrast, basal breast cancer cell lines do not express FOXA1, and loss of FOXA1 in luminal cells increases migration and invasion, characteristics of the basal subtype. To delineate an ER-independent role for FOXA1 in maintaining the luminal phenotype, and hence a more favourable prognosis, we performed cDNA microarray analyses on luminal FOXA1-positive, ER-positive (MCF7, T47D) and FOXA1-positive, ER-negative (MDA-MB-453, SKBR3) cell lines in the presence or absence of transient FOXA1 silencing. This resulted in three FOXA1 transcriptomes: (1) a luminal-signature (consistent across cell lines), (2) an ER-positive signature (restricted to MCF7 and T47D) and (3) an ER-negative signature (restricted to MDA-MB-453 and SKBR3). Use of Gene Set Enrichment Analyses (GSEA) as a phenotyping tool revealed that FOXA1 silencing resulted in a transcriptome shift from luminal to basal gene expression signatures. FOXA1 binds to both luminal and basal genes within luminal breast cancer cells, suggesting that it not only transactivates luminal genes, but also represses basal-associated genes. From these results we conclude that FOXA1 controls plasticity between basal and luminal cells, playing a dominant role in repressing the basal phenotype, and thus tumor aggressiveness, in luminal breast cancer cells. Although it has been proposed that FOXA1-targeting agents may be useful for treating luminal tumors, these data suggest that this approach may promote transitions toward a more aggressive cancer. FOXA1 siRNA treated breast cell lines compared directly to nonspecific siRNA treated cell lines using Agilent 4X44 microarrays.
2012-03-09 | E-GEOD-31003 | biostudies-arrayexpress
Project description:SNP6 profiling of metaplastic breast carcinoma Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic type of breast cancer, preferentially displaying a triple-negative phenotype (i.e. lacking estrogen receptor, progesterone receptor and HER2 expression). We sought to define the transcriptomic heterogeneity of MBCs on the basis of current gene expression microarray-based classifiers and to determine whether MBCs display gene copy number profiles consistent with those of BRCA1-associated breast cancers.
2014-10-31 | E-GEOD-57548 | biostudies-arrayexpress
Project description:INTRODUCTION: Basal-phenotype or basal-like breast cancers are characterized by basal epithelium cytokeratin (CK5/14/17) expression, negative estrogen receptor (ER) status and distinct gene expression signature. We studied the clinical and biological features of the basal-phenotype tumors determined by immunohistochemistry (IHC) and cDNA microarrays especially within the ER-negative subgroup. METHODS: IHC was used to evaluate the CK5/14 status of 445 stage II breast cancers. The gene expression signature of the CK5/14 immunopositive tumors was investigated within a subset (100) of the breast tumors (including 50 ER-negative tumors) with a cDNA microarray. Survival for basal-phenotype tumors as determined by CK5/14 IHC and gene expression signature was assessed. RESULTS: From the 375 analyzable tumor specimens, 48 (13%) were immunohistochemically positive for CK5/14. We found adverse distant disease-free survival for the CK5/14-positive tumors during the first years (3 years hazard ratio (HR) 2.23, 95% confidence interval (CI) 1.17 to 4.24, p = 0.01; 5 years HR 1.80, 95% CI 1.02 to 3.15, p = 0.04) but the significance was lost at the end of the follow-up period (10 years HR 1.43, 95% CI 0.84 to 2.43, p = 0.19). Gene expression profiles of immunohistochemically determined CK5/14-positive tumors within the ER-negative tumor group implicated 1,713 differently expressed genes (p < 0.05). Hierarchical clustering analysis with the top 500 of these genes formed one basal-like and a non-basal-like cluster also within the ER-negative tumor entity. A highly concordant classification could be constructed with a published gene set (Sorlie's intrinsic gene set, concordance 90%). Both gene sets identified a basal-like cluster that included most of the CK5/14-positive tumors, but also immunohistochemically CK5/14-negative tumors. Within the ER-negative tumor entity there was no survival difference between the non-basal and basal-like tumors as identified by immunohistochemical or gene-expression-based classification. CONCLUSION: Basal cytokeratin-positive tumors have a biologically distinct gene expression signature from other ER-negative tumors. Even if basal cytokeratin expression predicts early relapse among non-selected tumors, the clinical outcome of basal tumors is similar to non-basal ER-negative tumors. Immunohistochemically basal cytokeratin-positive tumors almost always belong to the basal-like gene expression profile, but this cluster also includes few basal cytokeratin-negative tumors. Keywords: Disease state analysis
2007-02-26 | GSE6768 | GEO
Project description:We developed a mouse model that captures radiation effects on host biology by transplanting unirradiated Trp53 null mammary tissue to sham or irradiated hosts. Gene expression profiles of tumors that arose in irradiated mice are distinct from those that arose in naïve hosts. Host irradiation induces a metaprofile consisting of gene modules representing stem cells, cell motility, macrophages and autophagy. Human orthologs of the host irradiation metaprofile discriminated between radiation-preceded and sporadic human thyroid cancers. An irradiated host centroid was strongly associated with estrogen receptor negative breast cancer. When applied to sporadic human breast cancers, the irradiated host metaprofile strongly associated with basal-like and claudin-low breast cancer intrinsic subtypes. Comparing host irradiation in the context of TGFβ levels showed that inflammation was robustly associated with claudin-low tumors. The association of the irradiated host metaprofiles with estrogen receptor negative status and claudin-low subtype suggests that host processes similar to those induced by radiation underlie sporadic cancers.
2013-04-04 | GSE42742 | GEO
Project description:We developed a mouse model that captures radiation effects on host biology by transplanting unirradiated Trp53 null mammary tissue to sham or irradiated hosts. Gene expression profiles of tumors that arose in irradiated mice are distinct from those that arose in naM-CM-/ve hosts. Host irradiation induces a metaprofile consisting of gene modules representing stem cells, cell motility, macrophages and autophagy. Human orthologs of the host irradiation metaprofile discriminated between radiation-preceded and sporadic human thyroid cancers. An irradiated host centroid was strongly associated with estrogen receptor negative breast cancer. When applied to sporadic human breast cancers, the irradiated host metaprofile strongly associated with basal-like and claudin-low breast cancer intrinsic subtypes. Comparing host irradiation in the context of TGFM-NM-2 levels showed that inflammation was robustly associated with claudin-low tumors. The association of the irradiated host metaprofiles with estrogen receptor negative status and claudin-low subtype suggests that host processes similar to those induced by radiation underlie sporadic cancers. Total RNA was extracted from mammary tumors derived from transplantations of non-irradiated p53null mammary fragments into irradiated hosts. We analyized a total of 32 p53null tumors from irradiated wild type mice: 9 from sham-irradiated hosts, and 23 from irradiated hosts. We also analyzed 24 tumors from irradiated TGFb1 heterozygote hosts: 6 from sham-irradiated hosts, and 18 from irradiated hosts.
2013-04-04 | E-GEOD-42742 | biostudies-arrayexpress
Project description:Purpose: To characterize the expression of phosphatases in estrogen receptor negative breast cancer Little is known about the role of phosphatases in the major estrogen receptor negative breast cancer phenotypes (i.e. those overexpressing ERBB2 and the triple negative). We carried out microarray phosphatome profiling in 41 estrogen receptor negative (ER-) breast cancer patients (as determined by immunohistochemistry (IHC)) containing both ERBB2+ and ERBB2- in order to characterize the differences between these groups by Statistical Analysis of Microarrays (SAM). Our findings point to the importance of the MAPK and PI3K pathways in ER- BCs as some of the most differentially expressed phosphatases (like DUSP4 and DUSP6) share ERK as substrate, or regulate the PI3K pathway (INPP4B, PTEN). These observations are also confirmed by pathway and GSEA analysis. It is shown that both ER- ERBB2+ and triple negative breast cancers have a distinctive pattern of phosphatase RNA expression. Surgical specimens from primary breast cancers that were estrogen receptor negative according to immunohistochemistry
2014-06-30 | E-GEOD-51999 | biostudies-arrayexpress
Project description:Tumor heterogeneity complicates patient treatment and can be due to transitioning of cancer cells across phenotypic cell states. This process is associated with the acquisition of independence from an oncogenic driver, such as the estrogen receptor (ER) in breast cancer, resulting in tumor progression, therapeutic failure and metastatic spread. Here we identify the transcription factor ONECUT2 (OC2) as a lineage plasticity regulator of breast cancer (BC) that suppresses the estrogen axis and promotes luminal to basal transition. OC2 is highly expressed in a substantial subset of hormone receptor negative human BC tumors and is associated with poor clinical outcome, lymph node metastasis and heightened clinical stage. We also show that OC2 is required for cell growth and survival in metastatic BC models and that it can be targeted with a small molecule inhibitor providing a novel therapeutic strategy for patients with OC2 active tumors.
2024-05-23 | GSE242540 | GEO