P 204 - Differences in antioxidant enzymes in tumour tissue and non-tumour adjacent tissue in colorectal cancer patients at different stages (III and IV)

Abstract

Colorectal Cancer (CRC) is one of the leading causes of death by cancer worldwide; its high mortality rate is mainly attributable to metastases. Oxidative stress has been classically related to cancer due to the harmful effects of free radicals, both in their onset and in their evolution. Recent studies have revealed the influence of non-tumour adjacent tissue on the progression and metastasis of CRC. Based on this, we have studied the protein levels of antioxidant enzymes by western blot comparing samples of non-tumour adjacent tissue and tumour tissue of CRC patients in advanced stages (III and IV). In the results obtained, higher levels of antioxidant enzymes have been observed in the tumour tissue than in the non-tumour adjacent tissue, although these differences are shortened in stage IV, due to the fact that stage IV patients present a significant increase in levels of antioxidant enzymes in non-tumour adjacent tissue. In addition, higher levels of antioxidant enzymes have been observed in the non-tumour adjacent tissue of patients in IV stage than in III This study emphasizes the importance of non-tumour adjacent tissue as a prognostic factor in the evolution of CRC cancer patients.