Among diet components, some
fatty acids are known to affect several stages of colon
carcinogenesis, whereas others are probably helpful in preventing
tumors. In light of this, our aim was to determine the composition of
fatty acids and the possible correlation with apoptosis in human colon
carcinoma specimens at different Duke's stages and to evaluate the effect of enriching human
colon cancer cell line with the possible reduced
fatty acid(s). Specimens of
carcinoma were compared with the corresponding non-neoplastic mucosa: a significant decrease of
arachidonic acid,
PPARalpha, Bad, and Bax and a significant increase of COX-2, Bcl-2, and pBad were found. The importance of
arachidonic acid in apoptosis was demonstrated by enriching a Caco-2 cell line with this
fatty acid. It induced apoptosis in a dose- and time-dependent manner via induction of
PPARalpha that, in turn, decreased COX-2. In conclusion, the reduced content of
arachidonic acid is likely related to carcinogenic process decreasing the susceptibility of
cancer cells to apoptosis.