Insulin-like Growth Factors (IGF), IGF-binding Proteins (IGFBP), and Vascular Endothelial Growth Factor (VEGF) in Blood Serum of Patients with Colorectal Cancer

Serum levels of insulin-like growth factors (IGF-1 and IGF-2), IGF-binding proteins (IGFBP-1, IGFBP-2, and IGFBP-3) and vascular endothelial growth factor (VEGF) were measured by standard ELISA technique in 95 primary colorectal cancer patients and 48 healthy individuals. Significant increase in serum levels of IGF-1, IGFBP-2, and VEGF and decrease in IGFBP-3 level were demonstrated in patients in comparison with the control group; in male patients, serum level of IGF-2 was also increased. Sensitivity of IGF-1 as the prospective diagnostic marker of colorectal cancer was 80% and specificity was 75% at the threshold level of 140 ng/ml. Serum levels of IGF-1 significantly decreased with age in both patients and healthy donors, but in patients, this correlation was much weaker. These parameters did not correlate with the main clinical and morphological indices, such as dissemination, localization, and histological structure of colorectal cancer.