Gene expression changes induced by bezafibrate, gemfibrozil, simvastatin, and atorvastatin on the β-oxidation and cholesterol biosynthesis pathways. The accession numbers and a short description of the genes present on the RU1 chip and belonging to the two pathways are shown on the left. Four treatments for each drug are shown. Treatments are labeled as drug name_dose_time. The gemfibrozil and simvastatin panels are placed between the columns corresponding to the fibrate and statin class averages, to highlight the fact that they share properties from both classes.