The effect of combination treatment with docosahexaenoic acid and 5-fluorouracil on the mRNA expression of apoptosis-related genes, including the novel gene BCL2L12, in gastric cancer cells

Docosahexaenoic acid (DHA) plays an important role in suppressing the growth of cancer. In this paper, the synergetic anticancer effect of combination DHA with 5-fluorouracil (5-FU) was investigated in gastric carcinoma cells. We found that DHA inhibited the growth of cultured SGC7901 cells at different concentrations in a dose- and time-dependent manner. Furthermore, the growth-inhibition activities of increasing concentration of 5-FU were markedly enhanced when different doses of 5-FU were administered in the combination with dose as low as 40 μg/ml of DHA. The early phase of apoptosis was increased in DHA- and 5-FU-treated cells. In the case of apoptotic genes expression in the combination-treated cells, BAX mRNA expression increased, whereas FAS, BCL-2, BCL2L12, and CASPASE-9 mRNA expression decreased. These results suggest that DHA strongly enhances the anticancer effect of 5-FU. Moreover, the application of both compounds on gastric cancer cells provides a new potential approach for cancer therapy.