SREBF1 and neoplasm: At week 14 (end of the dietary experiments), tumour growth was significantly enhanced in the HFD group compared with the LFD group (P=0.025, Supplementary Figure S1), but there were no significant differences in serum levels of insulin and insulin-like growth factor 1 (IGF-1) in the two groups, consistent with the results of our previous study.6 Next, we investigated the expression of FASN and SREBP-1, the critical transcriptional factor for FASN, in the xenograft mice.