IGF-I and IGFBP-3 levels and their correlations with carcinoembryonic antigen in colorectal cancer patients
Background: Colorectal cancer is one of the most frequently seen cancers worldwide. Currently, CEA is the most commonly used tumor marker in colorectal cancer. The changes in IGF/IGFBP equilibrium is also known to cause carcinogenesis. In this study, we aimed to monitor IGF-I/IGFBP-3 levels, the changes in IGF-I/IGFBP-3 ratio and correlations of these peptides with the common tumor marker CEA.
Materials and methods: 55 colorectal cancer patients and 35 control group patients were included in this study. Serum CEA, IGF-I and IGFBP-3 levels of all specimens were measured with chemiluminescence method.
Results: In colorectal cancer patients, IGF-I levels was found to be increased, IGFBP-3 levels decreased and IGF-I/IGFBP-3 ratio was increased; when compared to control group (p < 0.05). A moderately significant correlation was found between the conventional tumor marker CEA and IGF-I and IGF-BP3 (p = 0.001, r = 0.533 and p = 0.001, r = 0.573 respectively).
Conclusions: IGF-I/IGFBP-3 ratio seems to be increased in the colorectal cancer patients. When considered with the moderate correlation levels of these peptides with CEA, this increase in IGF-I/IGF-BP3 ratio may be useful in monitoring carcinogenesis in colorectal cancer patients among with CEA but more detailed and extensive studies in larger study groups needed to be carried out.
Keywords: Colorectal cancer, Carcinoembryonic antigen, Insulin like growth factor-I, Insulin-like growth factor binding protein-3, Tumor marker