Abstract
Lecithins are important constituents of biomembranes. In general, saturated fatty acids are present predominantly in the α-position and unsaturated ones in the β-position of lecithins. However, this positional specificity (of the fatty acids) is not always found, particularly in some experimental tumor lipids. It is described in this paper that lecithi ns of human stomach cancers were subjected to elucidate the positional specificity of the constituent fatty acids and the results obtained were as follows.
1. There was no significant difference in phospholipid composition between normal and cancer stomach tissues.
2. The main constituent fatty acids of the lecithins isolated from both stomach tissues were,16:0,16:1,18: 0,18:1,18:2 and 20: 4.
3. In lecithins of cancer tissues, compared to normal ones,16:0 decreased and 18:0,18: 1,18: 2 and 20: 4 increased, resulting in more unsaturates were present in th e lecithin molecules than the saturates. At the α-position, the decrease of 16:0 and increase of 18: 0,18: 1 and 18: 2 were found and the decrease of 16:0 was over the increase of 18:0. At the,β-position,18:1 and 16:0 decreased and 18: 2 a nd 20:4 increased.
The finding suggested that some metabolic disorders of lecithins were present in stomach cancer tissue.
