The Fra-1 transcription factor promotes tumor cell growth, invasion and metastasis. While characterizing five breast cancer cell lines derived from primary human breast tumors, we identified BRC-31 as a novel basal-like cell model that expresses elevated Fra-1 levels. BRC-31 cells display elevated FAK, SRC and ERK2 phosphorylation relative to luminal breast cancer models. Inhibition of this signaling axis, through the use of pharmacological inhibitors, reduces the phosphorylation and stabilization of Fra-1. Elevated integrin V3 expression in these cells suggested that integrin receptors might activate this FAK-SRC-ERK2 signaling axis to enhance Fra-1 phosphorylation. These cells also express high levels of uPAR, a GPI-anchored receptor that has been shown to enhance integrin-mediated signaling initiated by Vitronectin engagement. Transient knockdown of uPAR in BRC31 cells grown on Vitronectin reduces Fra-1 phosphorylation and stabilization and uPAR and Fra-1 are required for Vitronectin-induced cell invasion. In clinical samples, a molecular component signature consisting of Vitronectin-uPAR-uPA-Fra-1 predicts poor overall survival in patients with breast cancer and correlates with a Fra-1 transcriptional signature. Taken together, we have identified a novel-signaling axis that leads to phosphorylation and stabilization of Fra-1, a transcription factor that is emerging as an important modulator of breast cancer progression and metastasis.
Integrin-uPAR signaling leads to FRA-1 phosphorylation and enhanced breast cancer invasion.
Age, Disease, Disease stage
View SamplesIn this study, we used conditional knockout and gene expression approaches to understand global molecular and transciptional changes due to ablation of each integrin subunit.
Functional Redundancy between β1 and β3 Integrin in Activating the IR/Akt/mTORC1 Signaling Axis to Promote ErbB2-Driven Breast Cancer.
Specimen part
View SamplesMonoclonal antibodies (mAbs) targeting the oncogenic receptor tyrosine kinase ERBB2/HER2, such as Trastuzumab, are the standard of care therapy for breast cancers driven by ERBB2 overexpression and activation. However, a substantial proportion of patients exhibits de novo resistance. Here, by comparing matched Trastuzumab-naïve and post-treatment patient samples from a neoadjuvant trial, we link resistance with elevation of H3K27me3, a repressive histone modification catalyzed by Polycomb Repressor Complex 2 (PRC2). In ErbB2+ breast cancer models, PRC2 silences endogenous retroviruses (ERVs) to suppress anti-tumor Type-I interferon (IFN) responses. In patients, elevated H3K27me3 in tumor cells following Trastuzumab treatment correlates with suppression of IFN-driven viral defense gene expression signatures and poor response. Using an immunocompetent model, we provide evidence that EZH2 inhibitors promote IFN-driven immune responses that enhance the efficacy of anti-ErbB2 mAbs, suggesting the potential clinical benefit of epigenomic reprogramming by H3K27me3 depletion in Trastuzumab-resistant disease.
Reduction of Global H3K27me<sup>3</sup> Enhances HER2/ErbB2 Targeted Therapy.
Sex, Specimen part, Treatment
View SamplesTranscriptional profiles of HCMV or Mock infected neonatal and adult were anayzed
IL-12 and type I IFN response of neonatal myeloid DC to human CMV infection.
Specimen part, Time
View SamplesBackground: Kaposis sarcoma associated herpes virus (KSHV) is associated with tumors of endothelial and lymphoid origin. During latent infection, KSHV expresses miR-K12-11, an ortholog of the human tumor gene hsa-miR-155. Both gene products are microRNAs (miRNAs), which are important post-transcriptional regulators that contribute to tissue specific gene expression. Advances in target identification technologies and molecular interaction databases have allowed a systems biology approach to unravel the gene regulatory networks (GRNs) triggered by miR-K12-11 in endothelial and lymphoid cells. Understanding the tissue specific function of miR-K12-11 will help to elucidate underlying mechanisms of KSHV pathogenesis. Results: Ectopic expression of miR-K12-11 differentially affected gene expression in BJAB cells of lymphoid origin and TIVE cells of endothelial origin. Direct miRNA targeting accounted for a small fraction of the observed transcriptome changes: only 29 common genes were identified as putative direct targets of miR-K12-11 in both cell types. However, a number of commonly affected biological pathways, such as carbohydrate metabolism and interferon response related signaling, were revealed by gene ontology analysis. Integration of transcriptome profiling, bioinformatic algorithms, and databases of protein-protein interactome from the ENCODE project identified different nodes of GRNs utilized by miR-K12-11 in a tissue-specific fashion. These effector genes, including cancer associated transcription factors (TFs) and signaling proteins, amplified the regulatory potential of a single miRNA, from a small set of putative direct targets to a larger set of genes. Conclusions: This is the first comparative analysis of miRNA-K12-11s effects in endothelial and B cells, from tissues infected with KSHV in vivo. MiR-K12-11 was able to broadly modulate gene expression in both cell types. Using a systems biology approach, we inferred that miR-K12-11 establishes its GRN by both repressing master TFs and influencing signaling pathways, to counter the host anti-viral response and to promote proliferation and survival of infected cells. The targeted GRNs are more reproducible and informative than target gene identification, and our approach can be applied to other regulatory factors of interest.
A systems biology approach identified different regulatory networks targeted by KSHV miR-K12-11 in B cells and endothelial cells.
Specimen part, Cell line
View SamplesThe premature aging disorder Werner Syndrome (WS) is characterized by early onset of aging phenotypes resembling natural aging. In most WS patients there are mutations in the DNA helicase WRN, an enzyme important in maintaining genome stability and telomere replication. Interestingly, its clinical manifestations reflect a severe degree of deterioration for connective tissue, whereas the central nervous system is less affected. We suggest that the varied vulnerability to aging is regulated by an unknown mechanism that protects specific lineages of stem cells from premature senescence. To address this problem, we reprogrammed patient skin fibroblasts to induced pluripotent stem cells (iPSC). The expression profile for the differentiated normal and WS fibroblasts and undifferentiated iPSC were compared. A distinct expression profile was found between normal and WS fibroblasts, however, few changes of gene expression were found in iPSC. Our findings suggest an erasure of aging phenotype associated with WS in reprogrammed iPSC.
Telomerase protects werner syndrome lineage-specific stem cells from premature aging.
Sex, Age, Specimen part
View SamplesGene expression profiling of three PEL cell lines compare to three Burkitt's lymphoma lines to figure out the changed genes under KSHV latent infection.
The latency-associated nuclear antigen of Kaposi's sarcoma-associated herpesvirus modulates cellular gene expression and protects lymphoid cells from p16 INK4A-induced cell cycle arrest.
No sample metadata fields
View SamplesAberrant methylation has been postulated to play an important role in tumorigenesis. We report the use of methylated DNA immunoprecipitation (MeDIP) and whole-genome tiling arrays to investigate methylation changes in testicular germ cell tumor (TGCT) cells. Coupled to expression profiling changes, we found that only 22-26% of differentially methylated genes were also expressed differentially. This phenomenon was independent of the presence of CpG islands in the promoter. Differential methylation and expression of some of these genes were confirmed in testicular tumor tissue. A substantial number of differentially methylated regions in the human genome were not linked to annotated gene loci. Subsequent analysis indicated several microRNAs and small nucleolar RNAs were regulated by these differentially methylated regions. Our results demonstrate the power of the combination of MeDIP-chip analysis and expression profiling for discovery in cancer cells of epigenetically regulated genes and non-coding RNAs in cancer cells.
Genome-wide DNA methylation profiling reveals novel epigenetically regulated genes and non-coding RNAs in human testicular cancer.
Sex, Age, Specimen part, Cell line
View SamplesWe performed Ago HITS-CLIP to identify targets of viral and human miRNAs in latently KSHV-infected PEL cells Overall design: Ago HITS-CLIP was performed in two latently infected PEL cell lines, BCBL-1 and BC-3; Argonaute-immunoprecipitation of UV cross-linked Ago-miRNA-mRNA complexes, followed by RNA isolation, library construction, and high-throughput sequencing (Illumina GAxII); we performed 3 biological replicates for each cell line, two technical (sequencing) replicates of BCBL-1 biological replicate 1
Ago HITS-CLIP expands understanding of Kaposi's sarcoma-associated herpesvirus miRNA function in primary effusion lymphomas.
Cell line, Subject
View SamplesIn response to acute loss of the Ulp2 SUMO-specific protease, yeast become disomic for chromosome I (ChrI) and ChrXII. Here we report that ChrI disomy, which creates an adaptive advantage in part by increasing the dosage of the Ccr4 deadenylase, was eliminated by extended passaging. Loss of aneuploidy is often accompanied by mutations in essential SUMO-ligating enzymes, which reduced polySUMO-conjugate accumulation. The mRNA levels for almost all ribosomal proteins increases transiently upon initial loss of Ulp2, but elevated Ccr4 levels limit excess ribosome formation. Notably, extended passaging leads to increased levels of many small nucleolar RNAs (snoRNAs) involved in ribosome biogenesis, and higher dosage of three linked ChrXII snoRNA genes suppressed ChrXII disomy in ulp2? cells. Our data reveal that aneuploidy allows rapid adaptation to Ulp2 loss, but long-term adaptation restores euploidy. Cellular evolution restores homeostasis through countervailing mutations in SUMO-modification pathways and regulatory shifts in ribosome biogenesis. Overall design: In these comparisons, the ulp2? cells either carried a WT ULP2 plasmid or empty vector and were passaged for 50 or 500 generations. mRNA profiles of them were generated by sequencing, in triplicate, using Illumina HiSeq 2500 .
Distinct adaptive mechanisms drive recovery from aneuploidy caused by loss of the Ulp2 SUMO protease.
Subject
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