日本質量分析学会 第66回質量分析総合討論会

Program

Oral Sessions

Day 3, May 17(Thu.) 16:35-16:55 Room A (OrBit Hall)

Discovery of colorectal cancer biomarkers in serum extracellular vesicles by targeted proteomics

(1NIBIOHN Proteome Res, 2NIBIOHN Proteomics Drug Discovery)
oTakeshi Tomonaga1,2, Takashi Shiromizu1

Many biomarker candidate proteins for colorectal cancer (CRC) have been reported in the earlier literature including our report, however, none of them has been applied for clinical test or validated as useful biomarker. Recent advances in targeted proteomics enabled to validate hundreds of biomarker candidates. In this study, we aimed to verify previously reported CRC biomarker candidate proteins in serum extracellular vesicles (EVs) of CRC patients by selected reaction monitoring.
Using this technology, we verified 725 previously reported CRC biomarker candidate proteins that are functionally correlated with CRC in EVs from patients. Of these, 356 proteins were quantified, and 34 peptides (22 proteins) showed significant differences in the serum EVs between healthy controls and CRC patients of two independent cohorts (n = 77 and 84).
These peptides were evaluated as single or multiple markers. Four single peptides in annexin family proteins and eight combinations of peptides showed area under the curve >0.9 for discriminating between healthy controls and CRC patients. Furthermore, sensitivities of the four peptides of annexins A3, A4, and A11 for detection of stage 1 and stage 2 early CRC were >80%, which greatly exceeds the sensitivity of CEA. These peptides are promising biomarkers for early detection of CRC