The FASN gene has been investigated as a possible oncogene. FAS is upregulated in breast and gastric cancers, as well as being an indicator of poor prognosis, and so may be worthwhile as a chemotherapeutic target. FAS inhibitors are therefore an active area of drug discovery research.
FAS may also be involved in the production of an endogenous ligand for the nuclear receptor PPARalpha, the target of the fibrate drugs for hyperlipidemia, and is being investigated as a possible drug target for treating the metabolic syndrome. Orlistat which is a gastrointestinal lipase inhibitor also inhibits FAS and has a potential as a medicine for cancer.
In some cancer cell lines, this protein has been found to be fused with estrogen receptor alpha (ER-alpha), in which the N-terminus of FAS is fused in-frame with the C-terminus of ER-alpha.
An association with uterine leiomyomata has been reported.