Your new experience awaits. Try the new design now and help us make it even better

ORIGINAL RESEARCH article

Front. Mol. Biosci.

Sec. Molecular Diagnostics and Therapeutics

Volume 12 - 2025 | doi: 10.3389/fmolb.2025.1640508

ITRAQ and PRM-based quantitative saliva proteomics in gastric cancer: biomarker discovery

Provisionally accepted
Zhanyan LiuZhanyan Liu1Jieren LiuJieren Liu2Zaid ChacharZaid Chachar3Jimao MoJimao Mo2Haoran ChiHaoran Chi2Runtao WenRuntao Wen2Kaixin LuoKaixin Luo2Lei HuangLei Huang2Guanlin LiGuanlin Li2Chenhao ZhangChenhao Zhang2Yuanru MaoYuanru Mao2Yuanzhe CaiYuanzhe Cai2*Feijuan HUANGFeijuan HUANG4*Zhengzhi WuZhengzhi Wu4
  • 1Changsha Hospital of Traditional Chinese Medicine Affiliated to Hunan University of Traditional Chinese Medicine, Hunan, China
  • 2Shenzhen Technology University, Shenzhen, China
  • 3The Chinese University of Hong Kong, Shenzhen, China
  • 4Shenzhen Second People's Hospital, Shenzhen, China

The final, formatted version of the article will be published soon.

Select one of your emails

You have multiple emails registered with Frontiers:

Notify me on publication

Please enter your email address:

If you already have an account, please login

You don't have a Frontiers account ? You can register here

Salivary proteomics is a non-invasive, low-cost, easy-to-use, real-time method that has been widely used in cancer studies, and salivary biomarkers are of great significance in identification. Our study aims to detect saliva proteins that are changed in gastric cancer (GC) and trace out potential candidate proteins for novel noninvasive biomarkers. Here, we report the differentially expressed proteins (DEPs) in GC saliva, quantified and compared the GC group 1, 2 and normal samples through iTRAQ. We used gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, protein-protein interaction (PPI) map with validation by parallel reaction monitoring (PRM), and Kaplan–Meier (KM) survival analysis for functional annotation and to assess DEPs. We identified 671 proteins with one or more unique peptide segments in the iTRAQ analysis. Among them, 124 and 102 proteins were significantly differentially expressed in GC group 1 (n=12) and GC group 2 (n=13), respectively, compared to the non-GC group (n=11). A total of 56 overlapping DEPs were identified between GC 1 and 2, with 24 upregulated and 32 downregulated proteins. Functional enrichment analysis using GO, KEGG, PPI analysis, and PRM validation identified four key proteins, S100A8, S100A9, CST4, and CST5, which showed consistent differential expression. Notably, CST4 and CST5 were downregulated in saliva, contrary to their upregulation in GC tissue and blood. These findings highlight the potential diagnostic value of salivary proteins, particularly S100A8, S100A9, CST4, and CST5, in gastric cancer detection.

Keywords: iTRAQ, PRM, proteomic, gastric cancer, Saliva, biomarkers

Received: 04 Jun 2025; Accepted: 05 Aug 2025.

Copyright: © 2025 Liu, Liu, Chachar, Mo, Chi, Wen, Luo, Huang, Li, Zhang, Mao, Cai, HUANG and Wu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence:
Yuanzhe Cai, Shenzhen Technology University, Shenzhen, China
Feijuan HUANG, Shenzhen Second People's Hospital, Shenzhen, China

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

Supplementary Material