Proteomics-identified serum ROBO4 and VCAM-1 enable robust diagnosis and prognosis-associated biomarkers in colorectal cancer

Early diagnosis and prognosis assessment of colorectal cancer (CRC) require more effective biomarkers. Using data-independent acquisition (DIA) proteomics, we analyzed serum samples from CRC, colorectal adenoma, and healthy control groups, identifying 50 differentially expressed proteins including ROBO4 and VCAM-1. These candidate biomarkers were further validated by ELISA in an independent cohort of 300 participants (100 per group). Serum levels of ROBO4 and VCAM-1 were significantly elevated in CRC patients, demonstrating superior diagnostic performance (AUCs: 0.886 and 0.871, respectively) compared to conventional markers CA199 (AUC = 0.757) and CEA (AUC = 0.808). Both markers were significantly associated with clinical stage and lymph node metastasis. A nomogram integrating all four markers achieved excellent diagnostic ability (AUC = 0.969). Public database analysis confirmed that high expression of ROBO4 and VCAM-1 significantly correlated with poor overall survival. This study identifies and validates serum ROBO4 and VCAM-1 as promising diagnostic and prognosis-associated biomarkers for CRC through proteomic screening and large-scale cohort validation, supporting their potential utility for CRC detection and risk assessment.