Mountain View
biomedical and healthCAre Data Discovery Index Ecosystem
help Advanced Search
Title: Over-expression of miR-146a in basal-like breast cancer cells confers enhanced tumorigenic potential in association with altered p53 status      
availability:
available
aggregation:
instance of dataset
privacy:
not applicable
refinement:
curated
dateReleased:
07-14-2014
ID:
E-GEOD-52783
description:
The tumor suppressor p53 is the most frequently mutated gene in human cancers, mutated in 25-30% of breast cancers. However, mutation rates differ according to breast cancer subtype, being more prevalent in aggressive estrogen receptor (ER) negative tumors, basal-like and HER2 amplified subtypes. This heterogeneity suggests that p53 may function differently across breast cancer subtypes. We used RNAi-mediated p53 knockdown (KD) and antagomir-mediated KD of microRNAs to study how gene expression and cellular response to p53 loss differ in luminal vs. basal-like breast cancer. As expected, p53 loss caused down regulation of established p53 targets (e.g. p21 and miR-34 family) and increased proliferation in both luminal and basal-like cell lines. However, some p53-dependent changes were subtype-specific, including expression of miR-134, miR-146a, and miR-181b. To study the cellular response to miR-146a upregulation in p53-impaired basal-like lines, antagomir knockdown of miR-146a was performed. KD of miR-146a caused decreased proliferation and increased apoptosis, effectively ablating the effects of p53 loss. Furthermore, we found that miR-146a upregulation decreased NF-kB expression and downregulated the NF-kB-dependent extrinsic apoptotic pathway (including TNF, FADD, and TRADD) and antagomir-mediated miR-146a KD restored expression of these components, suggesting a plausible mechanism for miR-146a-dependent cellular responses. These findings are relevant to human basal-like tumor progression in vivo, since miR-146a is highly expressed in p53-mutant basal-like breast cancers. These findings suggest that targeting miR-146a expression may have value for altering the aggressiveness of p53 mutant basal-like tumors. reference x sample
keywords:
transcription profiling by array
format:
HTML
storedIn:
Array Express
qualifier:
not compressed
accessType:
landing page
authorization:
none
authentication:
none
primary:
true
accessURL: https://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-52783
format:
JSON
storedIn:
OmicsDI
qualifier:
not compressed
accessType:
download
authorization:
none
authentication:
none
primary:
false
accessURL: www.omicsdi.org/ws/dataset/arrayexpress-repository/E-GEOD-52783.json
format:
XML
storedIn:
OmicsDI
qualifier:
not compressed
accessType:
download
authorization:
none
authentication:
none
primary:
false
accessURL: http://www.omicsdi.org/ws/dataset/arrayexpress-repository/E-GEOD-52783.xml
ID:
SCR:014747
name:
Omics Discovery Index
abbreviation:
OmicsDI
homePage: http://www.omicsdi.org/