Fatty acid synthase expression is increased in neoplastic lesions of the oral tongue

Background. Fatty acid synthase (FASE) is required for fatty acid synthesis . Elevated levels of FASE have been observed in a variety of malignancies. Methods. We examined the expression of FASE in 56 primary squamous cell car cinomas (SCC) of the tongue using immunohistochemistry (IHC) with a monoclo nal antibody to FASE. Results: Immunoreactivity was low in histologically normal epithelium (0.42 +/- .07, n = 43), moderate in mildly dysplastic epithelium (1.41 +/- 11, n = 40), and strong in SCC of the tongue (1.64 +/- 10, n = 50). Both mild dy splasia and SCC stained more strongly than histologically normal epithelium (p<0.00001). Well-differentiated tumors showed increased immunoreactivity when compared to less well-differentiated tumors (p=0.044). Decreased overa ll survival was observed among patients with tumors with low immunoreactivi ty (p=0.04). Conclusions: Increased expression of FASE in dysplasia and squamous carcino mas of the oral tongue may be an indicator of both differentiation and earl y neoplastic change. FASE expression may be useful diagnostically, prognost ically, and as a potential target for therapy. (C) 1999 John Wiley & Sons, Inc.