Studies on the Interactions between Various Lectins and Blood Group Substances Prepared from Non-cancerous Mucosae and Cancer Tissues of Human Stomachs

Blood group substances (BGS) were separated from gastric cancers and non-cancerous mucosae and their blood group specific interactions were studied by means of affinity electrophoresis using blood group specific and non-specific lectins. By this method, the extents of the affinity of BGS to the specific lectins were quantitatively evaluated. BGSs from non-cancerous mucosae of group A patients showed a strong affinity with A-specific helix pomatia lectin (HP). Their affinity to HP was on the average 10 times stronger than those to non-specific concanavalin A or to B- or O-specific lectins. On the other hand, BGSs from cancer tissues of the group A patients showed only 1.5 times stronger affinity to HP than to concanavalin A. Similarly BGSs from non-cancerous mucosae of group O patients showed strong affinity to O specific ulex europeus lectin (UE). Their affinity to UE was on the average 2.5 times stronger than those to concanavalinA. Affinity of BGSs from cancer tissues of the group O patients to UE was not different from those to concanavalinA. From the results obtained, we concluded that the blood group specificity of stomach BGS diminishes at the cancerous change. Carbohydrate analyses and hemagglutination tests for BGSs ensured the finding obtained by the affinity electrophoresis.