Although avasimibe inhibited fluvastatin-induced ACAT2 mRNA expression in the breast tissue of the combination-treated mice, confirming that avasimibe effectively hit its target, the fluvastatin and avasimibe combination was completely ineffective in preventing breast cancer in vivo, with approximately 90% of mice developing tumors by 22 weeks, similar to the vehicle control group animals. This evidence concerns the gene ACAT2 and breast cancer.