Abstract
Colorectal cancer is one of the most frequently occurring types of cancer in developed countries and is a major cause of death from cancer. Nowadays, this type of cancer still lacks good predictive markers that both have diagnostic and prognostic value. To increase knowledge and to discover novel and potentially useful markers we investigated some members of the MMP family in relation to colorectal cancer. In tissues from colorectal cancer patients we found active and latent MMP-2 to correlate with stage of disease. They also appeared unfavourably linked, together with active and latent MMP-9, to the event of early recurrent disease after liver metastatectomy. Therefore, in cancer tissues, these MMPs may be relevant for predicting patient prognosis and this should be investigated further in larger and more divers patient groups, including more divers controls. ProMMP-2, levels in the blood of colorectal cancer patients were lower than those in healthy persons and showed potential diagnostic value in primary colorectal cancer. The latter applied also to the levels of the MMP inhibitor TIMP-1, but not to proMMP-9. Prior to disease relapse after liver metastatectomy, again, proMMP-2 levels appeared to have diagnostic value, predicting the recurrence of cancer. In blood the carcinoembryonic antigen remains the better predictive marker for patient prognosis and survival when compared to the MMPs. Ultimately, our studies, in blood and tissue, show that MMP-2 and MMP-9 relate differently to the cancer process. They should be investigated as individual markers and, in addition, we believe that future investigations should not only focus on the absolute levels of marker molecules but also on the relative levels.
