Over one million prostate biopsies are performed in the U.S. every year. However, pathology examination is not definitive in a significant percentage of cases due limited diagnostic tumor. We have observed that the microenvironment of prostate tumor cells exhibits numerous differential gene expression changes and have asked whether such information can be used to distinguish tumor from nontumor. We initially compared expression analysis data (Affymetrix U133plus2) from 18 volunteer biopsy specimens to 17 specimens containing largely tumor-adjacent stroma and identified 964 significant (p_adj < 0.01 and B > 0) expression changes. These genes were filtered to eliminate possible aging-related genes and genes expressed in tumor cells > 10% of the stroma cell expression level leading to 23 candidate genes (28 Affymetrix probe sets). A classifier based on the 28 probe sets was tested on 289 independent cases, including 195 tumor-bearing cases, 99 nontumor cases (normal biopsies, normal autopsies, remote stroma as well as pure tumor adjacent stroma) all with accuracies >85%, sensitivities >90% and specificities >85%. These results indicate that the prostate cancer microenvironment exhibits reproducible changes useful for categorization as tumor and nontumor.
In silico estimates of tissue components in surgical samples based on expression profiling data.
Subject
View SamplesProstate cancer gene expression profiles were studied in this project. A total RNA from 148 prostate sample with various amount of different cell types were hybridized to Affymetrix U133A arrays. The percentage of different cell types vary considerably among samples and were determined by pathologist. Cell type specific genes can be determined by linear regression using the methods of Stuart et al, PNAS, 2004.
In silico estimates of tissue components in surgical samples based on expression profiling data.
No sample metadata fields
View SamplesThe Her-2/Neu-positive mouse breast cancer cell line was serially co-cultured with minced brain, bone marrow, and lung tissue in an intravital microscopy chamber mounted on the dorsal skinfold of nude mice, alternating with growth in vitro. Gene expression analysis was performed on the cells grown in culture after sorting and further growth in vitro. Gene expression under these growth conditions differed in time and according to the co-cultivated organ tissue. This study reveals genes that are expressed by cells as they adapt differentially to various foreign tissue microenvironments, and may represent a paradigm to discover gene expression changes that occur immediately upon extravasation when cancer metastasizes.
Effects of different tissue microenvironments on gene expression in breast cancer cells.
Cell line
View SamplesPrevious studies have revealed that UV-stimulation of a variety of cells leads to activation of the EGF receptor, induction of Egr1, growth inhibition and apoptosis. On the other hand both Egr1 and EGF receptor activation are implicated in promoting the progression of prostate cancer. We treated M12 tumorigenic prostate epithelial cells which express little Egr1 with UV irradiation which rapidly activated the EGF receptor and elevated Egr1. Treatment with specific EGFR and ERKI/II inhibitors (PD153035 and UO126, respectively) confirmed that the upregulation of Egr1 was downstream of EGFR and ERKI/II Map kinase pathway. ChIP on chip experiments using Egr1 antibody identified 288 significantly bound promoters upon UV stimulation. Of these target genes, 40% had consensus Egr1 site in their promoters, considerably greater than that expected by chance (p < 0.005). The array binding results were validated by PCR analysis of 25 genes using DNA from conventional IP experiment. Affymetrix gene expression analysis of UV treated and control cells confirmed that a significant number of these bound promoters showed gene expression changes. Addition of siRNA to Egr1 confirmed that the gene expression changes were dependent upon Egr1 expression. Addition of EGF led to similar expression changes for nine tested genes. Proliferation and apoptosis assays confirmed that M12 cells undergo growth arrest and apoptosis following UV irradiation. Moreover, addition of EGF also promoted significant growth inhibition. These results indicate the M12 cells undergo a EGF receptor dependent apoptosis response upon UV-stimulation and that Egr1 mediates the regulation of numerous genes downstream of the EGF receptor that are associated with this response.
Egr1 regulates the coordinated expression of numerous EGF receptor target genes as identified by ChIP-on-chip.
No sample metadata fields
View SamplesThe Murphy Roth Large (MRL) mouse, a strain capable of regenerating right ventricular myocardium, has a high post-myocardial infarction (MI) survival rate compared with C57BL6/J (C57) mice. The biological processes responsible for this survival advantage are unknown.
Early postmyocardial infarction survival in Murphy Roths Large mice is mediated by attenuated apoptosis and inflammation but depends on genetic background.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A distinct microRNA signature for definitive endoderm derived from human embryonic stem cells.
Cell line, Time
View SamplesTotal RNA microarray data from Fresh-Frozen Glioblastoma tumor samples.
Epigenetic suppression of EGFR signaling in G-CIMP+ glioblastomas.
Specimen part, Disease stage
View SamplesHigh-fat diet (HFD) in normoxia causes a worsened phenotype in adult female flies compared to regular diet (RD). Intermittent hypoxia (IH) causes an opposite phenotype both when flies are on RD in IH compared to normoxia and even more dramatically when on HFD in IH compared to HFD in normoxia.
No associated publication
Sex, Specimen part
View SampleshESCs can differentiate into the three primary embryonic lineages (endoderm, mesoderm, ectoderm) as well as extraembryonic tissues. Definitive endoderm (DE) is the first step into the pathway to endoderm derived tissues: pancreas, liver, gut, lung.
A distinct microRNA signature for definitive endoderm derived from human embryonic stem cells.
Cell line, Time
View SamplesChanges occur in the lung epithelium after allergen challenge that may give insight into asthma pathogenesis and we sought to identify novelepithelial genes induced by allergen exposure.
Alternaria induces STAT6-dependent acute airway eosinophilia and epithelial FIZZ1 expression that promotes airway fibrosis and epithelial thickness.
Age, Specimen part
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