Clara, CA, USA) was used to define gene expression profiles from the samples.
Synthesis and labeling of cDNA targets, hybridization, and scanning of GeneChips
were carried out by the Integrative Genomics Core Facility at City of Hope.
Briefly, cRNA was generated according to the manufacturer’s protocol
using Affymetrix’s GeneChip Whole Transcript Sense Target Labeling Assay
Hybridization cocktails containing 5.5 μg of fragmented, end-labeled cDNA
were prepared and applied to GeneChip Human Gene 1.0 ST arrays. Hybridization
was performed for 16 h, and the arrays were washed and stained with a GeneChip
Fluidics Station 450 using FS450_0007 script. Arrays were scanned at 5 μm
resolution using Affymetrix GCS 3000 7G.
Raw intensity measurements of all probe sets were background-corrected,
normalized, and converted into expression measurements using Affymetrix’s
Expression Console v1.1.1. The Bioconductor “ArrayTools” package
was then used to identify the genes differentially expressed between the treated
and untreated samples. Significant genes were selected with a cutoff of adjusted
P < 0.05 and fold change of 2. The DAVID functional
annotation tool
then used to identify modulated KEGG signaling pathways.