Biopolymers and cell. 2001; 17 (6): 551 - 555

Investigation of DNA topoisomerase I as an autoantigen at the thyroid cancer

L. L. Sidorik, T. A. Rybkinska, O. G. Vigontina, M. I. Vudmaska, V. G. Naidenov, P. V. Pogribnyi, I. L. Lisovskii, L. P. Schvachko, I. Bronstein, V. V. Lyzogubov, E. A. Prihod'ko, V. S. Usenko, G. Kh. Matsuka

The data concerning DNA-Topoisomerase I (Topo-I) from human placenta as an autoantigen at the thyroid cancer are presented. A new effective scheme of the Topo-J purification using the High-Trap columns is described, as well as the enzyme physico-chemical properties and its immunoreactivity in the ELJSA and immunoblotting. It was shown that 46 % of the sera from patients suffering the thyroid cancer were immunoreactive against Topo-I, 36 % of autoantibodies from thyroid cancer patients sera recognized sequential determinants on the Topo-I molecule. The highest levels of immunoreacivity were observed in the sera of thyroid cancer patients accompanied by autoimmune thyroiditis. We suggest a possible linkage between the autoimmune processes and malignization of the thyroid gland cells.