Fatty Acid Synthase (FASN)

Fatty acid synthase (FAS) is enzymatic system composed of 272 kDa multifunctional polypeptide, in which substrates are handed from one functional domain to the next,  It has been investigated as a possible oncogene. FAS is up-regulated in breast cancers and as well as being an indicator of poor prognosis may also be worthwhile as a chemotherapeutic target.

Fatty acid synthase (FAS) is a multifunctional protein. Its main function is to catalyze the synthesis of palmitate from acetyl-CoA and malonyl-CoA, in the presence of NADPH, into long-chain saturated fatty acids. 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.