microRNA expression profiling of paired primary and lymph node metastatic breast cancer patients

Extracted total RNA from FFPE tissue were used for RNA labeling and hybridization on to the Agilent Human SurePrint 8 × 60k v16 miRNA microarray chip according to the manufacturer's protocol. Total RNA was extracted from FFPE tissue using the recover all total nucleic acid isolation kit (Ambion Inc., Life Technologies, USA) according to the manufacturer’s protocol. RNA was then subjected to labeling and hybridization on to the Agilent Human SurePrint 8×60k v16 miRNA microarray chip according to the manufacturer's protocol.