Description
SW480 were stably transfected with an episomal plasmid expressing GFP and miRNA34 from a bidirectional doxycyclin regulatable promoter (Bornkamm et al Nucleic Acids Res. 2005 Sep 7;33(16)). Polyclonal cell lines were obtained by selection with Hygromycin at 350ug/ml for 10 days. The cell llnes identified as GFP only express GFP, whereas the cell lines identified as miRNA34a express both GFP and miRNA34 under doxycyclin control. For the present experiment, cells were treated with 1ug/ml Docycyclin for 72h. Cells were harvested and total RNA was isolated using Trizol (Invitrogen). After RNA cleanup (RNeasy, Qiagen) Affymetrix 133 Plus 2.0 micorarrays were hybridized using standard techniques.