High-Throughput Olink Proteomics Elucidates the Immuno-Neurological Landscape of Gastric Cancer

Gastric cancer (GC) ranks as the third leading cause of cancer-related mortality globally. A comprehensive and precise proteomic study of GC tissues can yield detailed insights into its pathogenesis. This study employed the highly sensitive Olink technology to quantify the levels of 1034 selected proteins in tumor tissues, paired adjacent tissues, and normal tissues from Chinese GC patients. Through an examination of expression changing trends and differential expression across these tissue types, it was determined that the protein profile of tumor tissue exhibits distinct characteristics, whereas the protein profiles of adjacent and normal tissues are more similar. The 124 differentially expressed proteins (DEPs) are predominantly associated with inflammation, immunity, and neurology, with major contributions from protein families such as chemokines, interleukins, and CLECs. We also employed machine learning algorithms to identify potential biomarkers, including CCN4, FNDC1, and PGF. Furthermore, validation results obtained through transcriptome data and ELISA demonstrated a concordance with findings from Olink analysis. To the best of our knowledge, this study represents the inaugural proteomic investigation of GC tissue utilizing high-throughput Olink technology. It reveals distinctive proteomic characteristics at the tissue level and offers significant insights for the identification and validation of novel biomarkers.