ST6GAL1 and carcinoma: However, ST6Gal I seems to have no effect on it, because quantitative lectin-histochemical and immune-histochemical studies on the occurrence of α2,3 and α2,6 sialic acid residues in colorectal carcinomas showed that 2,6 sialylated glycoconjugates did not display any association with local tumor growth, while α2,3 sialylation positively correlated with tumor growth and significantly increased at tumor Stage I and Stage II, but decreased in advanced carcinomas [63].