[The vascular endothelial growth factor in patients with advanced ovarian cancer on the background of chemotherapy according to the AP scheme.]

Antiangiogenic therapy requires to search for molecular markers of angiogenesis in ovarian cancer (OC). The diagnostic and prognostic role of VEGFA in OC is controversial today. The aim of the study was to compare the serum level of VEGF, the cytoplasmic protein content and VEGF transcript in the tumor tissue of primary patients with advanced ovarian cancer and to analyze the relationship between these parameters and the response to standard polychemotherapy using the AP scheme. 82 primary patients with advanced OC were incladed in the study. The control group included 30 healthy women. All patients received adjuvant chemotherapy according to the AP scheme after surgery. The serum VEGF-A level was determined by direct immunoassay analysis "Human VEGF ELISA Kit" ("RayBiotech", USA). Analysis of the VEGF transcript in tumor tissue was performed by PCR-RT using TaqMan® Gene Expression Assay (Thermo Scientific) probes, and for the data normalization the 18S and GAPDH referee genes were used. To calculate the IHC score of cytoplasmic expression of VEGF, immunohistochemical reactions were performed in paired samples of OC patients using antibodies (GeneTex, USA). For the genotyping of patients' DNA, test systems for the analysis of functional polymorphisms of the VEGF-A C12143A, G634C (LLC "Sintol", Moscow) were used. The level of VEGF-A in the serum of patients with OC was increased in comparison with the norm and depended on the response to chemotherapy according to the AP scheme. However, the specificity of this indicator is insufficient for use in prognostic purposes. There are no significant differences in the cytoplasmic expression of VEGF-A, depending on the response to chemotherapy. VEGF mRNA level was increased in 58% of patients. There was no correlation between serum VEGF levels and the transcript in the tumor tissue. Genotyping showed that the combination of genotypes of CC / GG reduces the risk of recurrence by 2.6 times. The results obtained make it possible to question the value of studying the serum level of VEGF for evaluating the sensitivity of patients with OС to anti-angiogenic drugs.