[Markers and regulatory mechanisms in ovarian carcinoma].

Ovarian carcinoma is one of widely spread malignant diseases of female reproductive system. Mortality rate from it is much higher than from other female malignant diseases. During last 20 years the level of ovarian carcinoma in Ukraine and vast majority of other countries remains high manifesting no signs of decrease. This arouses interest of researchers to development of new methods of early diagnosis, therapeutic approach, prognostic criteria, especially biochemical ones, and means of prophylaxis of this pathology in medical scientific society. At present there are no specific diagnostic tests which would allow revealing the tumor on the initial stages of its development. In spite of vide arsenal of tumor markers, the only reliable test for ovarian carcinoma is determination of antigen CA-125. The results of basic modern research are discussed in this survey. They are aimed at finding out regulatory mechanisms connected with metabolism of L-arginine, activities of ATP-hydrolase systems and searching new markers of ovarian carcinoma. The main possible candidates for this role are determined.

[Arginase and NO-synthase pathways of L-arginine metabolism in peripheral blood lymphocytes of patients with ovarian cancer].

The peculiarities ofarginase and NO-synthase pathways of L-arginine metabolism in peripheral blood lymphocytes of patients with ovarian cancer were studied. It was shown that the development of cancer pathology is associated with an imbalance in the NO synthesis in blood lymphocytes. The reason for such imbalance is the activation of arginase and inducible isoform of NO-synthase (iNOS) and significant inhibition of its constitutive isoform. The analysis of the kinetic properties of NOS of blood lymphocytes of patients with ovarian cancer was carried out. It was shown that the affinity constant of iNOS affinity for L-arginine is 5.4-fold lower than for eNOS of blood lymphocytes of persons in the control group. The inhibition of eNOS occurs via non-competitive type and is related to the reduction of maximum reaction rate.