BACKGROUND AND AIM:

Gastric cancer (GC) is a common and fatal malignancy with a worldwide occurrence. There still lacks effective biomarkers for precisely evaluating GC. Saliva is a biological fluid with enormous diagnostic potentials which emerged many advantages. We aimed to discover the novel biomarkers for accurately distinguishing early GC based on saliva glycopatterns.

METHODS:

We used Aleuria Aurantia Lectin (AAL)-magnetic particle conjugates to isolate fucosylated glycoproteins in the pooled saliva of healthy volunteers (HV, n = 51) and patients with atrophic gastritis (AG, n = 51) or GC ( n = 51), following to release the N - and O -linked glycans from the isolated proteins with PNGase F and NaClO, and further identified the released glycans by MALDI-TOF/TOF-MS, respectively.

RESULTS:

A total of 9/9, 8/11, and 9/9 fucosylated N -/ O -linked glycans were annotated in the isolated salivary proteins from HV, AG, and GC, respectively. Among these, six fucosylated N -linked glycansand four O -linked glycans exhibited significantly increased expression levels in GC, while five fucosylated N -linked glycans and ten fucosylated O -linked glycans exhibited significantly decreased expression levels in GC. The proportion of fucosylated N -linked glycans was decreased in GC (41.66%) compared with AG (43.63%) and HV (52.57%), as well as the fucosylated O -linked glycans was apparently decreased in GC (19.58%) compared with AG (25.43%) and HV (55.54%).

CONCLUSIONS:

This study could provide pivotal information to distinguish among HV, AG, and GC, and facilitate the discovery of biomarkers for GC diagnosis based on precise alterations of N - and O -linked glycans in saliva.