Atra effect on ERBB2 and RARA-coamplified SKBR-3 cells

RNA was extracted with Rneasy Micro Kit (Qiagen, France) from SKBR3 cells treated with 1 uM ATRA. The quantity and purity of the extracted RNA was evaluated using a NanoDropTM spectrophotometer and its integrity measured using an Agilent BioanalyzerTM. For microarray hybridizations, 500 ng of total RNA from each RNA sample was amplified and labeled with two fluorescents dye (Cy5 and Cy3) using the Quick Amplification Labeling kit (Agilent Technologies, Palo Alto, CA, USA) following the manufacturer's protocol. Cy3-labeled and Cy5-labelled cRNA were hybridized to the Agilent Human Whole Genome Oligo Microarray format 4x44K (Agilent Technologies), prior to washing and scanning.