Objective: to assess the expression and prognostic value of vascular endothelial growth factor A (VEGF-A), fibroblast growth factor 2 (FGF-2) and their receptors VEGFR-1, -2; FGFR-1, -2, as well as platelet-derived growth factor receptors (PDGFR-α, PDGFR-β) in paired samples of primary tumors and tumor thrombi in renal cell carcinoma (RCC).Materials and methods. Expression of VEGF-A, FGF-2, VEGFR-1, -2; FGFR-1, -2; PDGFR-α, -β was studied in paired surgical samples of primary tumors and tumor thrombi in 25 patients with clear cell RCC pT3a–T4N0–1M0–1 and tumor venous thrombosis by immunohistochemical assay using the appropriate Abcam/Santa Cruz Biotech antibodies from the immunohistochemical staining kit Invitrogen. Expression levels were evaluated by a semi-quantitative method (H-score). The analysis of the correlation between expression levels of VEGF-A, FGF-2, VEGFR-1, -2; FGFR-1, -2; PDGFR-α, -β and RCC characteristics, as well as evaluation of their influence on the outcome of RCC were performed.Results. VEGF-A, FGF-2, as well as VEGFR-1, -2; FGFR-1, -2; PDGFR-α, -β were expressed in the cytoplasm and on the membrane of the primary tumor and tumor thrombus cells in RCC patients. Tumor thrombus cells were characterized by lower expression of VEGFR-1, VEGFR-2, PDGFR-α (p <0.05 for all) and tendency to lower expression of VEGF-A (p = 0.060), FGF-2 (p = 0.046), FGFR-1 (p = 0.077) and FGFR-2 (p = 0.090) compared with primary tumor cells. RCC Furman grade correlated with the expression levels of VEGFR-1 (p = 0.035) and FGFR-1 (p = 0.022) in the primary tumor cells, tumor invasion into venous wall correlated with the expression levels of VEGFR-1 (p = 0.023) and FGFR-2 (p = 0.005) on the thrombus cells. VEGFR-2 overexpression in the primary tumor cells was associated with significant decrease of overall survival (OS) rate (p = 0.011). There was a tendency to OS deterioration in cases with overexpression of VEGFR-2 (p = 0.093) and VEGF-A (p = 0.095) in the tumor thrombus cells. One-year OS in patients with ³2 identified risk factors was 27.3 %, <2 risk factors – 87.5 % (p = 0.004).Conclusion. Tumor thrombus cells in RCC patients expressed VEGF-A, FGF-2, VEGFR-1, -2; FGFR-1, -2; PDGFR-α, -β less active than the cells of the primary tumor. Overexpression of growth factors and tyrosine kinases correlated with RCC Furman grade and tumor venous wall invasion. Overexpression of VEGFR-2 in both primary tumor and thrombus cells in combination with hypoexpression of VEGF-A in the thrombus negatively influenced on OS.

Renal cell carcinoma (RCC) ranks first in mortality among urogenital tumors and is the most common disease after prostate and bladder cancer. Early detection of RCC allows immediately undertaking appropriate treatment, which significantly increases the survival of patients. In the case of the asymptomatic RCC, timely diagnosis in the early stages is usually difficult. To date, the problem of searching for molecular markers of clear cell RCC, which allows to determine the stage, metastatic potential and prognosis of disease, or select a treatment regimen remains topical. Of particular interest are early-stage biomarkers of RCC and its metastatic potential, as well as markers that can be obtained by non-invasive or minimally invasive methods. This review presents modern methods for diagnosing RCC using biomarkers.

Introduction The aim of our study was to investigate expression levels and the prognostic value of multiple growth factors and their receptors in the primary tumor cells of renal cell carcinoma (RCC). Material and methods Expression of vascular endothelial growth factor (VEGF)A, fibroblast growth factor (FGF)2, vascular endothelial growth factor receptor (VEGFR)1, VEGFR2, FGFR1, FGFR2, platelet-derived growth factor receptor (PDGFR)α, and PDGFRβ was investigated in 65 primary RCC specimens by immuhistochemical staining using the appropriate antibodies. Expression levels were evaluated by the semi-quantitative method. A search for correlations of expression levels of investigated growth factors and receptors with RCC features and patients outcomes was performed. Results Expression of all growth factors and their receptors was detected both on the surface and in the cytoplasm of the primary tumor cells in RCC patients. The expression of all analyzed factors was interconnected. FGFR2 expression correlated with the largest number of other growth factors and receptors. A strong correlation was revealed between high expression of the studied markers, high Fuhrman grade, and advanced RCC stages. In a univariate analysis overexpression of VEGFR2 (p <0.0001) and FGFR2 (p = 0.014) had negative influence on cancer-specific survival. Conclusions Expression of growth factors and tyrosine kinase receptors in the primary tumor cells is strongly interconnected and associated with unfavorable features of RCC.

Purpose: to study the expression of vascular endothelial growth factor (vegf-a) and its receptors (vegfr-1 and vegfr-2) in renal cell carcinoma (rcc) cells and assess the effect of the expression levels of these markers on the tumor characteristics and prognosis of patients with rcc.Material and methods. The study included 65 patients with rcc (pt1a-t4n0/+m0/+). All patients underwent radical surgery. Histological tumor tissue samples obtained during surgery were used for the study. Expression of vegfa, vegfr-1, -2 was studied by immunohistochemical staining using appropriate antibodies to receptors and growth factors.Results. Expression of vegf and vegfr-1 and vegfr-2 receptors was ound in the cytoplasm and on the membrane of primary tumor cells of patients with rcc. There was a significant direct correlation of overexpression of the markers with g 3-4 anaplasia (vegfr-1, -2) and signs of significant tumor extension, including high pt category (vegfr-1, -2), larger size of the primary tumor (vegfr-1 , -2), tumor invasion of paranephria (vegf, vegfr-1), tumor venous thrombosis (vegfr-1, -2), multiple metastases (vegf-2), metastases in the adrenal gland (vegf, vegfr-2) and liver (vegfr-1) (p<0.05). There was a trend towards a significant effect of the level of vegf expression on the risk of progression of rcc after cytoreductive nephrectomy (p=0.0821). A tendency towards a significant effect of the level of vegfr-2 expression on the risk of death from rcc was revealed (p=0.089). No other relationships between the expression of vegf-a/vegfr-1, -2 and the prognosis of rcc were found (p>0.05).Conclusion. Expression of vegfa, as well as vegfr-1 and vegfr-2 receptors, was found on the surface and in the cytoplasm of cells of the primary tumor of patients with rcc (pt1a-t4n0/+m0/+). There was a significant correlation between vegf/vegfr overexpression with a high grade (g3-4) tumor anaplasia and significant tumor extension. In univariate analysis, a significant adverse effect on specific survival of vegfr-2 overexpression was observed. In regression analysis, vegfr-2 overexpression tended to independently affect specific survival. These results show the importance of vegf/vegfr expression as biomarkers in renal cell carcinoma.

Background. The incidence of brain gliomas firmly occupies a leading position among all central nervous system tumors – 40–50 % of the cases detected, more than half of them are glioblastoma. Existing cell lines and cultivation methods do not reflect all the features of the three-dimensional (3D) organization of native glioblastoma. The use of temozolomide leads to the development of drug resistance and acute relapse, followed by a poor clinical outcome. The development of resistance is largely associated with the presence of tumor stem cells in the population and intratumoral heterogeneity. Obtaining 3D cultures from the primary material will allow us to save the stem cell pool and tumor-specific features.The study objective. Get a 3D model based on primary cell cultures, which allows you to save a heterogeneous population and the original phenotype of tumor cells.Materials and methods. We used U-87MG human glioma cells and GBM002 primary cell culture obtained from surgical material with a confirmed diagnosis of glioblastoma. Neurospheres were obtained from cell lines, the growth of which was monitored using the InCell Analyzer 6000 automatic cell analysis system. Flow cytometry was used to determine the CD133+ cell content. The expression of the receptor tyrosine kinases VEGFR1, VEGFR2 (endothelial growth factor type 1 and 2 receptors), FGFR2 (fibroblast growth factor receptor type 2) and the hypoxia marker HIF-1α (hypoxia inducible factor, 1α) in the neurospheres was evaluated using confocal microscopy.Results. GBM002 glioblastoma cells isolated from the surgical material formed neurospheres, while the number of CD133+ cells increased from 1–2 to 16–19 % compared with two-dimensional cultures. During long-term cultivation of cells with non-cytotoxic doses of temozolomide, it was found that such cells form smaller neurospheres compared to control cells. It was shown that the expression of receptor tyrosine kinases during cultivation of GBM002 glioblastoma cells in neurospheres differs from that in two-dimensional cultures. We found that in neurospheres, the expression of FGFR2 and VEGFR1, is significantly increased.Conclusion. 3D cultivation of primary cultures allows one to obtain a more heterogeneous population of tumor cells that reflects the spatial heterogeneity of cells, increase the pool of stem cells and recreate hypoxia conditions inside the brain micro-tumors.