Activities of the enzymes participating in purine and freeradical metabolism in cancerous human colorectal tissues

ÖZTÜRK H. S., Karaayvaz M., Kaçmaz M., Kavutcu M., Akgül H., DURAK İ.

Cancer Biochemistry Biophysics, cilt.16, sa.1, ss.157-168, 1997 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 16 Sayı: 1
  • Basım Tarihi: 1997
  • Dergi Adı: Cancer Biochemistry Biophysics
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Sayfa Sayıları: ss.157-168
  • Anahtar Kelimeler: Colorectal cancer, Free radical enzymes, Purine salvage enzymes
  • Ankara Üniversitesi Adresli: Evet

Özet

Activities of adenosine deaminase, 5′-nucleotidase, xanthine oxidase, superoxide dismutase, glutathione peroxidase and catalase enzymes were measured in cancerous and non-cancerous adjacent colorectal tissues from 10 patients. Activities of DNA turn-over enzymes (ADA, 5′NT and XO) were found increased and those of free-radical metabolizing enzymes (SOD, GSH-Px and CAT) decreased in cancerous tissues compared with those of non-cancerous adjacent ones. Malondialdehyde (MDA) concentrations in cancerous tissues were also found higher than those of non-cancerous tissues, which indicated accelerated lipid peroxidation in the cancerous tissues. In the correlation analysis, disordered enzymatical relations were observed between the enzymes of both metabolic pathways. Results suggest that activities of purine metabolizing enzymes increase to cope with accelerated purine metabolism in cancerous tissues and, enzymatic antioxidant defense potential of cancerous tissues decreases due to carcinogenic processes in the tissues. Reduced antioxidant defense system makes the cancerous tissue more vulnerable to toxic effects of some freeradical species.