title: Effects of olive oil polyphenols on fatty acid synthase gene expression and activity in human colorectal cancer cells.
abstract: Oleuropein (OL) and hydroxytyrosol (HT), the main olive oil polyphenols, possess anti-proliferative effects in vitro. Fatty acid synthase, a key anabolic enzyme of biosynthesis of fatty acids, plays an important role in colon carcinoma development. Our aim was to investigate whether gene expression of FAS, as well as its enzymatic activity, is regulated by HT and OL in two human colon cancer cell lines, as HT-29 and SW620. In addition, we investigated the effects of these polyphenols on growth and apoptosis in these cells. FAS gene expression and activity in treated HT-29 and SW620 cells were evaluated by real-time PCR and radiochemical assay, respectively. Cell growth and apoptosis, after polyphenols treatment, were measured by MTT test and flow cytometry, respectively. The inhibition of proliferation, detected after HT treatment, was mediated by an inhibition of FAS expression and its enzymatic activity in SW620 cells, while the anti-proliferative effect in HT-29 cells seems to be independent from FAS. OL exerted an anti-proliferative effect only on SW620 cells with a mechanism which excluded FAS. Olive oil polyphenols used were able to induce apoptosis in both cell lines studied. The increase of apoptosis in these cells was accompanied by the block of cell cycle in the S phase. This study demonstrates that HT and OL may induce anti-proliferative and pro-apoptotic effects only in certain human colorectal cancer cell types. These effects are FAS mediated only in SW620 cells after treatment with HT.
authors: Maria
authors: M
authors: Notarnicola
authors: Simona
authors: S
authors: Pisanti
authors: Valeria
authors: V
authors: Tutino
authors: Domenica
authors: D
authors: Bocale
authors: Maria Teresa
authors: MT
authors: Rotelli
authors: Antonio
authors: A
authors: Gentile
authors: Vincenzo
authors: V
authors: Memeo
authors: Maurizio
authors: M
authors: Bifulco
authors: Enzo
authors: E
authors: Perri
authors: Maria Gabriella
authors: MG
authors: Caruso