Immunohistochemical expression of MMP-7 protein and its serum level in colorectal cancer

The study objective was to determine the presence of MMP-7 in cancer tissue in correlation with its serum level in patients diagnosed with colorectal cancer (CRC). In 45 patients with CRC, MMP-7 expression was assessed immunohistochemically on FFPE slides in tumours (N = 37) and in the corresponding surgical margin sample. MMP-7 serum level was measured preoperatively. The expression of MMP-7 in cancer tissue was much stronger as compared to the normal intestinal mucosa. Also the level of MMP-7 in the serum of CRC patients was higher than in healthy subjects (N = 24) (p < 0.01). The tumour located in the colon showed higher expression of MMP-7 than CRCs located in the rectum (p < 0.05), whereas the higher MMP-7 serum level showed correlation with older age (p = 0.005), tumour size less than 5 cm (p < 0.05), higher Dukes' stage (p < 0.05) and distant metastases (p < 0.05). The increased serum level of MMP-7 in CRC patients may indicate the presence of distant metastases.