Colorectal cancer (CRC) is an important global burden, and the discovery of biomarkers for screening and monitoring is a current challenge. The present study aimed to determine the serum concentration of ROBO4 and CLEC14A in CRC patients and assess the clinical value of these diagnostic and progression biomarkers in CRC. The ROBO4 and CLEC14A levels were measured using ELISA tests. Blood sera were tested in 32 CRC patients and 16 controls at two time points (before and after surgery).
The serum concentrations of ROBO4 and CLEC14A were significantly higher in CRC patients than non-cancer controls; the concentrations were already higher in TNM stage I+II CRC patients. The sensitivitiy and specificity of ROBO4 and CLEC14A in distiguishing cancer patients form controls ranged from 71.9% to 100% and from 84.5% to 100%, respectively. The serum ROBO4 concentration was associated with the TNM stage, depth of invasion, and lymph node and distant metastases. No significant relationship was observed between the CLEC14A concentration and the tumor site or the N and M stages. The level of ROBO4 was statistically lower 3 months after the surgery, compared to the level noted prior to the operation. The concentration of CLEC14A decreased in the postoperative period, compared to preoperative one; however, the decline was not statistically significant. Our preliminary study has provided evidence that ROOB4 and CLEC14A seem to be suitable biomarkers for clinical diagnostic purposes. However, ROOB4 appears to be more appropriate for assessment of CRC progression.