Plasma concentrations of angiopoietin-1, angiopoietin-2 and Tie-2 in colon cancer

Background/Aim: despite the rapidly accumulating histopathological data reporting differences in the expression of members of the angiopoietin family on the surface of various normal and tumour cells, data for these growth factors in plasma from cancer patients, including colon cancer, are scarce. The aims of the present study were to measure the plasma concentrations of Ang-1, Ang-2 and Tie-2 in colon cancer patients, and to assess the correlation between the concentrations of these factors and the stage of the tumor. Patients and methods: the study cohort included 36 patients (18 male, 18 female) with colon cancer (mean age 52.6 ± 15.0), and 36 sex- and agematched, healthy controls who were free of inflammatory, neoplastic, atherosclerotic and connective tissue disease, recruited from hospital staff and attendees at hospital for check-up. Concentrations of Ang-1, Ang-2 and Tie-2 were measured using the enzyme-linked immunosorbent assay (ELISA) method. Results: concentrations of Ang-2 (median 3,188.0 pg/mL, min: 1,070.5-max: 5,765.5) and Tie-2 (median 22 ng/mL, min:12-max:46) were significantly higher in patients with colon cancer, while concentrations of Ang-1 were not statistically different between the groups. Furthermore, concentrations of Ang-2 (median 4,292.0 pg/mL, min: 3,090.0-max: 5,765.5) were found to be significantly higher in stage III patients compared to stage II patients, whereas no difference was found between the concentrations of Ang-1 and Tie-2 in different colon cancer stages. Conclusion: plasma concentrations of Ang-1, Ang-2 and Tie-2 may be valuable, additional, tumor markers in colon cancer that should be tested in further trials