Glycan biosynthesis pathway

The glycan biosynthesis pathway is a fundamental metabolic network responsible for the assembly, attachment, and processing of complex carbohydrate structures (glycans) onto proteins and lipids [5, 11]. This process, which includes N-linked and O-linked glycosylation, occurs primarily within the endoplasmic reticulum and Golgi apparatus and is essential for protein folding, stability, and cellular recognition [11, 12]. Glycans play critical roles in mediating cell-cell interactions, immune system modulation, and signal transduction [1, 5]. Aberrant activity within this pathway is a hallmark of various diseases, particularly cancer, where altered glycosylation patterns facilitate tumor metastasis and immune evasion [3, 11]. For example, increased branching and sialylation of surface glycans can help tumor cells avoid detection by the immune system [11, 13]. Consequently, the enzymes and metabolic intermediates of this pathway, such as glycosyltransferases and nucleotide sugars, are significant therapeutic targets [2, 13]. Drugs like miglustat and swainsonine have been developed to modulate these processes by inhibiting specific enzymes within the pathway [3]. However, the ubiquitous and essential nature of glycosylation in healthy tissues presents a major challenge for achieving therapeutic selectivity and avoiding systemic toxicity [2, 8]. Ongoing research into glycomics and glycoengineering continues to uncover new opportunities for precision medicine and the development of glycan-based therapeutics [4, 6].

Other names

Glycosylation pathwayGlycan metabolic pathwayHexosamine biosynthetic pathwayN-glycan biosynthesisO-glycan biosynthesis

Drugs targeting the glycan biosynthesis pathway typically act by inhibiting specific enzymes such as glycosyltransferases (e.g., DPAGT1) or glycosidases (e.g., alpha-mannosidase II), competing with natural substrates as glycomimetics, or depleting the pool of nucleotide sugar donors like UDP-GlcNAc and GDP-fucose [2, 3, 4, 13].