15-Lipoxygenase-1 expression suppresses the invasive properties of colorectal carcinoma cell lines HCT-116 and HT-29

Colorectal carcinoma (CRC) is often lethal when invasion and/or metastasis occur. 15-Lipoxygenase-1 (15-LO-1), a member of the inflammatory eicosanoid pathway, oxidatively metabolizes linoleic acid and its expression is repressed in CRC. In this study, we investigated the hypothesis that the lack of 15-LO-1 expression in CRC cells might contribute to tumorigenesis. Therefore we introduced 15-LO-1 into HCT-116 and HT-29 cells that do not have detectable levels of 15-LO-1. Our data indicate that expression of 15-LO-1 significantly decreased cell proliferation and increased apoptosis. In addition, we observed a reduction in adhesion to fibronectin, anchorage-independent growth on soft agar, cellular motility and ability to heal a scratch wound, and migratory and invasive capacity across Matrigel. 15-LO-1 expression also reduced the expression of metastasis associated protein-1, a part of the nucleosome remodeling and histone deacetylase silencing complex. We propose that 15-LO-1 expression in CRC might contribute to the inhibition of metastatic capacity in vitro and can be exploited for therapeutic purposes. (Cancer Sci 2009;100: 2283-2291).