A preliminary study on gastric cancer plasma in Singapore

B55

Gastric cancer is one of the leading causes of cancer-related death and has remarkable predominance in Asian population, especially among the Chinese ethnic group. Early detection is a key pillar in cancer management. Due to its minimally invasive nature, several groups have attempted to discover gastric cancer biomarkers from the blood using SELDI-based approach. While a certain degree of success has been achieved, we are interested to employ the state-of-the-art isotope-based, LC-MS/MS method as a complementary tool for gastric cancer biomarker discovery. This study employed IgY-12 columns to deplete the high abundant plasma proteins, with the intention to identify differentially expressed low abundant plasma proteins between health subjects and gastric cancer patients. The relative protein quantification and identification was obtained using isobaric tags (iTRAQ) coupled with LC-MALDI-MS-MS analysis. A total of 158 proteins were identified from duplicates experimental set-up, where 24 and 15 proteins were found to be decreased and increased in expression levels, respectively. Further validation will be carried out to investigate the specificity and sensitivity of candidate proteins for early detection of gastric cancer.