The multiple alterations of Heparan sulphate in cancer

Introduction Heparan sulphate is a complex polysaccharide that contains specific structural patterns generated through a series of interdependent enzymatic reactions that can involve various isoenzymes with differences in their specificities, responsible for the modification of the structure of heparan sulphate in physiological and pathological processes. The aim of this review is to discuss the multiple alterations of heparan sulphate in cancer. Discussion Tumour cells exhibit altered growth patterns and metabolism. This is supported by deregulated expression of multiple gene sets associated with tumour development and progression. Malignant cancers are characterized by their invasiveness and can even metastasize to distant locations in the body. Heparan sulphate proteoglycans are implicated in these processes and can influence the growth, invasion and metastatic properties of cancerous cells. Cells exercise exquisite control over heparan sulphate composition and sequence, varying among cell types, development stages as a result of cell transformation in pathological processes. Numerous tumours show quantitative and structural alterations of heparan sulphate chains, largely caused by changes in the expression of the enzymes responsible for their biosynthesis, particularly at the fine structure level. Conclusion This article focuses on reviewing the type of changes that occur at different stages of heparan sulphate chain biosynthesis in various tumours. Altered transcription can occur in any phase of heparan sulphate biosynthesis, but is particularly frequent at the level of the family of the 3-O-sulphotransferases, and the families of the 6-Osulphotransferases and extracellular sulphatases. The result is the alteration of the ligand binding sites responsible for directing specific cell signalling effects, facilitating tumour progression.