Identification of N- and O-linked glycans recognized by AAL in saliva of patients with atrophic gastritis and gastric cancer

Article type: Research Article

Authors: Shu, Jian^a | Yu, Hanjie^a | Du, Haoqi^a | Zhang, Jiaxu^a | Zhang, Kun^a | Li, Xiaojie^b | Xie, Hailong^{c; *} | Li, Zheng^{a; *}

Affiliations: [a] Laboratory for Functional Glycomics, College of Life Sciences, Northwest University, Xi’an, Shaanxi, China | [b] Department of Pothology, First People’s Hospital of Chenzhou, Chenzhou, Hunan, China | [c] Institute of Cancer Research, University of South China, Hengyang, Hunan, China

Correspondence: [*] Corresponding authors: Zheng Li, Laboratory for Functional Glycomics, College of Life Sciences, Northwest University, No. 229 Taibai Beilu, Xi’an 710069, Shaanxi, China. E-mail: [email protected]. Hailong Xie, Institute of Cancer Research, University of South China, No. 28 West Changsheng Rd., Hengyang 421001, Hunan, China. E-mail: [email protected].

Abstract: 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.

Keywords: Saliva, gastric cancer, MALDI-TOF/TOF-MS/MS, N- and O-Linked glycan

DOI: 10.3233/CBM-171087

Journal: Cancer Biomarkers, vol. 22, no. 4, pp. 669-681, 2018