Histochemical properties of mucosubstances in normal mucosa and
neoplasms of 100 operated cases with colonic
carcinoma were investigated by using several new methods, such as paradoxical
concanavalin A (con A) staining and modified PAS reactions for
sialic acids. Acidity of goblet cell-type
mucin (GCM) of the normal mucosa varied with the depth of the crypt, as well as with different segments of the large intestine, whereas surface coat-type
mucin (SCM) mainly consisted of
sulfomucin throughout the large intestine. In addition, the PAS reactivity revealing the presence of O-acetylated
sialic acid and the labile class III con A reactivity were demonstrated as hallmarks characterizing the colonic GCM. In
carcinoma tissues,
sialomucin was more abundant than in the normal mucosa. Goblet-type
tumor cells were found in 59 cases. Moreover, O-acetylated
sialic acid and the labile class III con A reactivity persisted in GCM of the goblet-type
tumor cells. GCM of the adjacent mucosa of the
neoplasms showed a decrease in
sulfomucin in 95 cases and a marked increase in the labile class III con A reactivity in 97 cases, while the histochemical properties of SCM in this region remained unchanged.