The influence of fatty acids on normal and transformed human liver cells in culture

Mammals are incapable of the synthesis of certain polyunsaturated fatty acids and must fulfil their needs from plant sources. These polyunsaturates are further desaturated and chain elongated by the mammal, and quantitatively the most important site is the liver. The enzymes concerned with this process are the desaturases and these have been shown to be lost with cell transformation. We incubated normal human liver cells and a hepatoma cell line with fatty acids of differing degrees of unsaturation and chain length, to ascertain whether the transformed cells would exhibit the same response to the fatty acids as the normal liver cells. There were no differences in the way the two cell types reacted to the saturated fatty acid, but a mixed response to the monounsaturate. The two plant-derived polyunsaturates caused more of the hepatoma cells to die, and this effect was more pronounced with the longer chain more unsaturated compounds. The three fatty acids that are precursors for eicosanoid synthesis showed the least effect on the normal cells, but still caused hepatoma cell death to a degree very similar to that caused by the plant polyunsaturates.