Clinical implications of gene dosage and gene expression patterns in diploid breast carcinoma (transcriptomic profiling)

Genomic and expression profiling using 38K BAC array-CGH and Illumina HT-12 beadchips were performed on 97 diploid invasive breast tumors to assess the impact of gene dosage on gene expression patterns and the effect of other mechanisms on transcriptional levels. Patient stratification was performed according to axillary lymph node status (node-negative, pN0; node-positive, pN1) and overall survival (>8-year survivors; breast cancer-specific mortality within 8 years of diagnosis). Array-CGH results was validated by FISH using tumors showing HER2/neu gene amplification and expression profiling was confirmed using qPCR for 16 transcripts. Total RNA was isolated from fresh-frozen tissue samples