At the present time, there is no common point of view to the role of circulating neutrophils (NP) in emergence and development of neoplasia. It is suggested that due to high functional plasticity, the neutrophils may exhibit both pro- and antitumor activity. In order to study the NP phenotype at different stages of cervical neoplasia (CN), we have evaluated their absolute and relative amounts, myeloperoxidase activity, spontaneous and induced NST-test markers, and the level of intracellular cationic proteins. Spontaneous production of elastase and active forms of matrix metalloproteinases, the levels of IL-2, IL-8, IL-18, IFNy, G-CSF were determined in the NP cell lysates and in blood serum. The formation of extracellular traps (NET) was evaluated using 1-day cultures of Saccharomyces cerevisiae as an inducer. We examined 31 patients with cervical intraepithelial neoplasia (CIN) and 21 primary patients with cervical cancer (CC, Ia stage according to FIGO scale), as well as 25 practically healthy women. We revealed increased spontaneous and inducible oxygen-dependent cytolytic and phagocytic activity and spontaneous production of NET if compared to normal values, along with decreased absolute NP numbers in patients with CIN, thus suggesting the antitumor activity of NP. The levels of “pro-tumor” cytokines (MMP-9, IL-2 and G-CSF) become increased over normal levels as early as at the CIN stage, both for the neutrophils and blood plasma. High levels of regulatory IFNy and neutrophil-priming IL-8 in blood plasma do not presume any use of exogenous NP-activating factors at the stage of cervical dysplasia. At the initial stage of cervical cancer, the absolute NP amounts are significantly increased compared to normal counts. However, despite increased spontaneous oxygen-dependent cytolytic activity, the NPs have a significantly reduced activity of phagocytosis and sharply increased spontaneous production of NET, thus, generally, being characteristic to the “pro-tumorous” NP phenotype. IL-2 levels are elevated, and MMP-9 values are still increased in NP and blood plasma of patients with CC (stage Ia). Hence, the obtained results suggest some changes of NP phenotype to a pro-tumorous pattern during transition from intraepithelial dysplasia to cervical cancer. These results allowed us to design an algorithm for examining women with suspected cervical cancer, including IL-2 measurement in blood serum, and MMP-9 amounts in the NP lysates
