Total RNA was prepared by using RNeasy kit (Invitrogen, Carlsbad, CA). Samples were prepared in biological triplicates. Equal amount from each sample was subjected to biotinylation using BioArray High Yield RNA Transcript Labeling System (Enzo Life Sciences, Farmingdale, NY, USA). Equal amount cRNA from each sample was labeled, purified and fragmented by using GeneChip Sample Cleanup Module (Affymetrix, Santa Clara, CA, USA). Following the manufacturer's protocols, the Human Genome U133 Plus 2.0 Array (Affymetrix, Santa Clara, CA) was applied for gene expression analysis (UCLA Microarray Core Facility).
