p53 reactivation in liver tumors

We induced liver tumors by transforming liver progenitor cells (LPC) with retroviruses expressing oncogenic Ras coupled to tetracycline transactivator together with an inducible shRNA targeting p53. Transformed LPCs were orthotopical transplanted into recipient livers and after tumor onset mice were fed with either Doxycycline containing chow or normal chow. 8 days later tumors were harvested and RNA was extracted. RNA was extracted using Trizol. For microarray experiment, HrasV12 driven liver tumors harboring tet-off shp53 were treated with Doxycycline for 0 day (p53 OFF, as control) or 8 days (p53 ON). Samples were assessed by Affymetrix 430 2.0 mouse microarray.