Isoenzymes of N-acetyl-β-hexosaminidase in human pleomorphic adenoma and healthy salivary glands: a preliminary study

Abstract

The present data indicate that HEX activity and activity of its isoenzymes in tumour specimens is significantly and consistently elevated, and thus suggest the need for further studies on the degradation of glycoconjugates, both in healthy salivary glands and PA. It appears that HEX may be considered as a new tumour marker in these salivary gland diseases.

O-GlcNAcylation enhances anaplastic thyroid carcinoma malignancy

“…The lysosomal β-N-acetylglucosaminidase is a type of O-GlcNAcase. The enhancement of its degradative activity has been observed to be associated with O-GlcNAcylation level in a variety of human cancer types (21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Additionally, a previous study proposed OGA activity to be significantly higher and O-GlcNAcylation to be lower in tumor tissue compared with corresponding normal tissue (31).…”

The activity of selected glycosidases in salivary gland tumors.

“…HEX was the most active lysosomal exoglycosidase in tissue of salivary gland tumor, blood serum and saliva of patients with tumor [12,13]. Tumors of salivary glands and associated inflammation increase biosynthesis and movement of lysosomal exoglycosidases from tumor tissue to blood and saliva.…”

“…The exoglycosidases degrade, in consequence, glycoproteins, proteoglycans, glycolipids that form the cellular membrane and intercellular matrix. Among exoglycosidases there are: N-acetyl-β-hexosoaminidase (HEX), β-glucuronidase (GLU), β-galactosidase (GAL), α-mannosidase (MAN) and α-fucosidase (FUC) [9][10][11][12][13]. Abstract: The monitoring of the patients after salivary gland tumors surgery is an important clinical issue.…”

Elevation of nucleocytoplasmic β-N-acetylglucosaminidase (O-GlcNAcase) activity in thyroid cancers

“…The enhancement of lysosomal ß-N-acetylglucosaminidase degradative activity in different human cancers, i.e. gastric, renal, breast, lung, glial and salivary gland is well documented (6)(7)(8)(9)(10)(11)(12)(13)(14)(15).…”

“…Two major lysosomal hexosaminidase isozymes, A and B were extensively studied because dysfunction of either of them results in the accumulation of gangliosides and other glycoconjugates within the lysosome causing the neurodegenerative disorders known as Tay-Sachs and Sandhoff disease (2,5). Moreover, the enhancement of ß-hexosaminidase degradative activity in different human cancer tissues and in serum or urine of patients with cancers is well documented (6)(7)(8)(9)(10)(11)(12)(13)(14)(15).…”