ACTIVITY OF CYSTEINE CATHEPSINS IN THE TISSUES AND BIOLOGICAL FLUIDS OF PATIENTS WITH ONCOLOGIC BRAIN DISEASES

Abstract

The transformation of a normal cell into an invasive cancer cell consists of several stages, which are characterised by clear histological and time periods. The aim of the work was to determine levels of activity of lysosomal cysteine cathepsins B, H and L in the blood plasma and urine of healthy and ill people with benign (benign meningiomas, neurinomas, angiomas) and malignant brain tumours (glioblastomas, astrocytomas) before and after operation.The tumours were types by histostructure, histogenesis and degree of malignancy. Cathepsin B activity was determined by hydrolysis of N,α-benzoyl-D,L-arginine-p-nitroanilide, cathepsin H activity – by hydrolysis of L-leucine β-naphthylamide (Leu-NA), cathepsin L activity – by ratio to azocasein (1%), which was denatured with 3.0 M urea. It was proved that determination of activity of cysteine cathepsins in biological fluids of patients can have an informative character in diagnostics and monitoring of the therapy of oncologic diseases of brain.It was shown that the levels of activity of lysosomal cycteine cathepsins B, L, H are definitely changed with respect to control indices in the studied biological fluids (the blood serum, urine) of patients. It was determined that in the postoperative material of benign brain tumours cathepsin L activity is higher than in case of malignant transformation of cells of brain tissues. It was shown that the level of cathepsin B activity in the postoperative material of patients with malignant brain tumours grows with the degree of the disease severity.It was supposed that in case of the brain cancerogenesis both disorganisation of membranes of lysosomes and presence of cytolytic processes of cells of tissues are identified, which results in release of lysosomal cysteine cathepsins in the blood, which in case of probable failure of mechanisms of control of proteolytic activity in the tissues of the organism under conditions of cancerogenesis, demonstrate excessive activity