Brain tumors: Regulation of angiogenesis.

Abstract

e13540 Background: Cancer implicates pathological angiogenesis. The problem of treatment for primary and metastatic brain tumors is still unsolved. In addition to main angiogenic functions, VEGF family performs important mediator functions in the immune system. The role of VEGF family in central nervous system tumors is poorly studied. Our purpose was to study the levels of factors of angio- and lymphangiogenesis in tissues of glioblastomas (G), brain metastases (MTS), meningiomas and corresponding peritumoral area. Methods: Tissues of tumor and peritumoral zone (PZ) obtained during the surgery from 22 patients with G, 14 patients with brain MTS from breast cancer and 12 meningioma patients, mean age 39.2±4.8 years, were studied. Levels of VEGF-A, VEGFR-1, VEGF-C and VEGFR-3 were determined by ELISA. The data were processed using Statistica 10 program. The significance of differences was determined by Student's t-test. Results: VEGF-A levels in tissues of G and MTS were higher than in meningioma tissues by 74.7 and 94.5 times, respectively; levels of VEGF-R1 were 2.7 and 3.9 higher, and the VEGF-A/VEGF-R1 coefficient was 28.1 and 24.1 times higher, respectively. Levels of VEGF-C and VEGF-R3 were escalated only in G tissues compared to meningiomas (by 1.7 times on average). The VEGF-С/VEGF-R3 coefficient was similar in all studied tumors. VEGF-A levels were higher in PZ of G and MTS compared to PZ of meningiomas – by 78.2 and 110.7 times, respectively, while VEGF-R1 level was higher in G PZ only (by 5.5 times). The VEGF-A/VEGF-R1 coefficient was 14.5 and 128.5 times higher, respectively. VEGF-C level in PZ of G was escalated compared to meningiomas by 6.5 times, in MTS – by 1.6 times. VEGFR-3 contents did not differ significantly in all PZ samples, but the VEGF-С/VEGF-R3 coefficient was higher in PZ in G by 9 times and in MTS by 2 times. Conclusions: Compared to benign meningiomas, angio- and lymphangiogenesis are activated in glioblastoma tissue and angiogenesis – in metastatic tissue. Lymphangiogenesis is more active in peritumoral zone of glioblastomas compared to metastatic tissue, and angiogenesis is more active in peritumoral zone of metastases.