Abstract
Sialic acids, a subset of nine carbon acidic sugars, often exist as the terminal sugars of glycans on either glycoproteins or glycolipids on the cell surface. Sialic acids play important roles in many physiological and pathological processes via carbohydrate-protein interactions, including cell–cell communication, bacterial and viral infections. In particular, hypersialylation in tumors, as well as their roles in tumor growth and metastasis, have been widely described. Recent studies have indicated that the aberrant sialylation is a vital way for tumor cells to escape immune surveillance and keep malignance. In this article, we outline the present state of knowledge on the metabolic pathway of human sialic acids, the function of hypersialylation in tumors, as well as the recent labeling and analytical techniques for sialic acids. It is expected to offer a brief introduction of sialic acid metabolism and provide advanced analytical strategies in sialic acid studies.
Highlights
The term “sialic acid” first appeared in 1952 to describe N-acetylneuraminic acid, a major product released by mild acid hydrolysis of glycolipids in the brain or salivary mucins [1,2]
The released sialic acids are pumped back into the cytosol, where they can enter into the cytosol, where they can enter another cycle of sialyl glycoconjugate production or be broken another cycle of sialyl glycoconjugate production or be broken down by N-acetylneuraminate lyase down by N-acetylneuraminate lyase (NAL) to ManNAc and pyruvate [23]
We summarize the functions of sialic acids during tumor progression, especially in immune escape, tumor proliferation and metastasis, tumor angiogenesis and apoptosis resistance
Summary
The term “sialic acid” first appeared in 1952 to describe N-acetylneuraminic acid, a major product released by mild acid hydrolysis of glycolipids in the brain or salivary mucins [1,2]. 50 -monophosphate N-acetylneuraminic acid synthetase (CMAS) to form CMP-Neu5Ac [15]. CMP-Neu5Ac is transferred to the glycoconjugates in the Golgi apparatus by family of linkage-specific sialyltransferases. The released sialic acids are pumped back into the cytosol, where they can enter into the cytosol, where they can enter another cycle of sialyl glycoconjugate production or be broken another cycle of sialyl glycoconjugate production or be broken down by N-acetylneuraminate lyase down by N-acetylneuraminate lyase (NAL) to ManNAc and pyruvate [23]. We summarize the functions of sialic acids during tumor progression, especially in immune escape, tumor proliferation and metastasis, tumor angiogenesis and apoptosis resistance. We introduce the prevalent analytical methods, including the sialic acid quantification and labeling strategies by bio-affinity, the chemical reaction, and metabolic labeling.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
