E-GEOD-46200 - LGR5 positivity defines stem-like cells in colorectal cancer

Status
Released on 19 April 2013, last updated on 3 June 2014
Organism
Homo sapiens, Mus musculus
Samples (42)
Arrays (2)
Protocols (13)
Description
To further elucidate the role of the intestinal stem cell marker Leucine-rich-repeat-containing G-protein-coupled receptor 5 (LGR5) in colorectal cancer (CRC), we exposed Lgr5-EGFP-IRES-Cre-ERT2 mice to azoxymethane/dextrane sodium sulfate (AOM/DSS) which induces inflammation-driven colon tumors. Tumors were then flow-sorted into fractions of epithelial cells that expressed high or low levels of Lgr5 and were characterized using gene expression profiling. In the AOM/DSS-induced mouse colon tumors Lgr5 high cells showed higher levels of several stem cell-associated genes and higher Wnt signaling than Lgr5 low tumor cells and Lgr5 high normal colon epithelial cells. To further elucidate the role of the intestinal stem cell marker Leucine-rich-repeat-containing G-protein-coupled receptor 5 (LGR5) in colorectal cancer (CRC), we transduced SW480 CRC cells with lentiviral shRNA constructs to silence LGR5 expression. This resulted in a depletion of spheres but did not affect adherently growing cells. Spheres expressed higher levels of several stem cell-associated genes than adherent cells. Notch signaling was down-regulated upon LGR5 silencing. This was confirmed by immunohistochemistry against cleaved NOTCH1. Normal mouse colons and AOM/DSS-induced mouse colon tumors were flow-sorted into Lgr5 high and low cells before gene expression was measured. Fifteen independent experiments were performed using seven individual mice for normal colons and eight for tumors. Appropriate LGR5 status was confirmed by real-time qRT-PCR before measuring silencing induced gene expression. Three independent experiments were performed for each cell fraction using separately cultured cells for each experiment.
Experiment type
transcription profiling by array 
Contacts
Daniela D Hirsch, Thomas Ried, Timo Gaiser, Yue Hu
MIAME
PlatformsProtocolsFactorsProcessedRaw
Files
Investigation descriptionE-GEOD-46200.idf.txt
Sample and data relationshipE-GEOD-46200.sdrf.txt
Raw data (1)E-GEOD-46200.raw.1.zip
Processed data (1)E-GEOD-46200.processed.1.zip
Array designsA-GEOD-13497.adf.txt, A-MEXP-724.adf.txt
Links