Expression data from Control, Uninfected and BRAF infected cells
Transcriptomics Dataset
FAIR Metrics
0 evaluations
General Information
AccessionGSE46801
TitleExpression data from Control, Uninfected and BRAF infected cells
DescriptionMelanocytes within benign human nevi are the paradigm for tumor suppressive senescent cells in a pre-malignant neoplasm. These cells typically contain mutations in either the BRAF or N-RAS oncogene and express markers of senescence, including p16. However, a nevus can contain 10s to 100s of thousands of clonal melanocytes and approximately 20-30%% of melanoma are thought to arise in association with a pre-existing nevus. Neither observation is indicative of fail-safe senescence-associated proliferation arrest and tumor suppression. We set out to better understand the status of nevus melanocytes. Proliferation-promoting Wnt target genes, such as cyclin D1 and c-myc, were repressed in oncogene-induced senescent melanocytes in vitro, and repression of Wnt signaling in these cells induced a senescent-like state. In contrast, cyclin D1 and c-myc were expressed in many melanocytes of human benign nevi. Specifically, activated Wnt signalling in nevi correlated inversely with nevus maturation, an established dermatopathological correlate of clinical benignancy. Single cell analyses of lone epidermal melanocytes and nevus melanocytes showed that expression of proliferation-promoting Wnt targets correlates with prior proliferative expansion of p16-expressing nevus melanocytes. In a mouse model, activation of Wnt signaling delayed, but did not bypass, senescence of oncogene-expressing melanocytes, leading to massive accumulation of proliferation-arrested, p16-positive non-malignant melanocytes. We conclude that clonal hyperproliferation of oncogene-expressing melanocytes to form a nevus is facilitated by transient delay of senescence due to activated Wnt signaling. The observation that activation of Wnt signaling correlates inversely with nevus maturation, an indicator of clinical benignancy, supports the notion that persistent destabilization of senescence by Wnt signaling contributes to the malignant potential of nevi. We used microarrays to detail the global programme of gene expression after lentiviral infection of BRAF in 3 replicates.
Landing Pagehttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE46801
RepositoryGene Expression Omnibus
Tools used to analyze the dataset

Keyword
Dataset Accession

Enrichr
Published May 2016
A comprehensive gene set enrichment analysis web server 2016 update
7759
65
Characteristic Direction
Published March 2014
A geometrical multivariate approach to identify differentially expressed genes
26829
GeneMANIA
Published June 2010
Biological network integration for gene prioritization and predicting gene function
7435
L1000CDS2
Published August 2016
An ultra-fast LINCS L1000 Characteristic Direction signature search engine
7756
PAEA
Published November 2015
Enrichment analysis tool implementing the principal angle method
3879
Canned Analyses generated with the dataset

Dataset Accession
Tool Name
Direction
Geneset

Small molecules which mimic BRAF overexpression
The L1000 database was queried in order to identify small molecule perturbations which mim...
Small molecules which reverse BRAF overexpression
The L1000 database was queried in order to identify small molecule perturbations which rev...
Enrichment analysis of genes dysregulated in BRAF overexpression
An enrichment analysis was performed on the top most dyresgulated genes determined by appl...
Interaction network and enrichment analysis of genes downregulated in BRAF overexpression
The analysis explores the gene interaction network and pathway enrichment of the top 50 mo...
Interaction network and enrichment analysis of genes upregulated in BRAF overexpression
The analysis explores the gene interaction network and pathway enrichment of the top 50 mo...
Enrichment analysis of genes downregulated in BRAF overexpression
An enrichment analysis was performed on the top 500 most downregulated genes identified by...
Enrichment analysis of genes upregulated in BRAF overexpression
An enrichment analysis was performed on the top 500 most upregulated genes identified by a...
FAIR Evaluation
Sorry, you must be signed in to evaluate this object.