These effects, however, appear to be cancer type-specific, with DECR1 shown to be decreased in mouse models of breast cancer and in clinical breast tumors compared to normal mammary gland [302, 303], and ectopic expression of DECR1 in HER2/neu-transformed breast cancer cells reducing tumorigenesis—an effect linked to reduced de novo lipogenesis [303]. This evidence concerns the gene ERBB2 and breast cancer.