Serum EphA2 as a Promising Biomarker for the Early Detection and Diagnosis of Colorectal Cancer.

BACKGROUND: EphA2, a receptor-type tyrosine kinase, is overexpressed in several cancers, including colorectal cancer (CRC), and can be detected as soluble EphA2 in serum. This study aimed to investigate the relationship between soluble EphA2 and CRC. METHODS: Serum samples were collected from 65 patients with CRC and 19 healthy individuals. Time-series changes in soluble EphA2 levels were measured in CRC cell lines to verify the release of EphA2 into the culture medium. RESULTS: Soluble EphA2 levels were significantly higher in patients than in healthy individuals (p < 0.0001). Specifically, even in early-stage cancer, there was a notable difference between healthy individuals and patients with Stage I CRC (p = 0.00298), highlighting the potential of EphA2 as a biomarker for early detection. Additionally, correlations were observed with tumor size (p = 0.0346), depth of invasion (p = 0.0311), and lymphatic invasion (p = 0.0431). A receiver operating characteristic (ROC) analysis yielded an area under the curve (AUC) of 0.90 with 93.8% sensitivity and 78.9% specificity at a cutoff value of 448 pg/mL. CONCLUSIONS: These findings suggest that serum EphA2 could serve as a valuable biomarker for the early detection of CRC, offering a practical and minimally invasive alternative to conventional tumor markers.