Stage-Dependent Levels of Brain-Derived Neurotrophic Factor and Matrix Metalloproteinase 9 in the Prognosis of Colorectal Cancer

The development of sensitive and non-invasive biomarkers for the early detection of CRC and determination of their role in the individual stages of CRC. MMP-9 expression in serum and tissue, and BDNF expression in plasma were detected using the ELISA method. MMP-9 and BDNF in the tissue were also determined by immunohistochemical staining. To assess the balance between changes in survival and tumor progression, we compared BDNF/MMP-9 ratios in tissues of living and deceased individuals. The tissue BDNF/MMP-9 ratio (evaluated immunohistochemically) decreased significantly with the progression of the disease in living patients. The BDNF/MMP-9 ratio was statistically significantly reduced in stages II and III compared to the benign group. However, in deceased individuals, the ratio showed an opposite tendency. The determination of the tissue BDNF/MMP9 ratio can be used as a prognostic biomarker of CRC.