Factors of angiogenesis (VEGF and CD34) in primary and recurrent soft tissue sarcomas.

Abstract

e23545 Background: The tumor ability to induce and maintain angiogenesis is one of the main stages of its development. Studies of molecular mechanisms of angiogenesis showed that the dynamic balance that ensures the formation and development of new vessels inside the tumor depends on pro- and anti-angiogenic factors. VEGF and the CD34 endothelial cell marker are considered among the main activators of angiogenesis. Our purpose was to study characteristics of angiogenesis in primary and recurrent soft tissue sarcomas. Methods: The study included 30 patients with primary sarcomas (group 1) and 26 patients with recurrent sarcomas (group 2). Sections of tissues embedded in paraffin blocks were studied by immunohistochemistry using the Thermo Scientific 480S automated stainer. The Reveal Polyvalent HRP-DAB Detection System was used for the visualization. The density of blood vessels stained with antibodies against VEGF and CD34 was determined. The statistical analysis of results was performed in the STATISTICA 10.0 program (StatSoftInc., USA). Results: The numbers of blood vessels ranged: CD34 in group 1 – 7-16 blood vessels in one field of view; in group 2 – 2-18 vessels. VEGF in group 1 – 2-20 vessels, with up to 40 vessels in 3 cases (11.5%) only; in group 2 – 5-11 vessels, with up to 20 vessels in 2 cases (7.7%). The average numbers of microcirculatory vessels stained with antibodies against VEGF and CD34 were: CD34 –12.2±1.04 and 8.4±1.4 (p = 0.0247) in groups 1 and 2, respectively; VEGF – 12.8±4.06 and 8.4±11.6 (p = 0.3074) in groups 1 and 2, respectively. Conclusions: The IHC analysis showed the minimal numbers of microcirculatory vessels in one field of view in patients with recurrent soft tissue sarcomas. The value was 1.5 times lower for both CD34 and VEGF, compared to patients with primary tumors. However, only CD34 value was statistically significant (the Mann–Whitney U-test). Probably, a certain decrease in angiogenesis factors in recurrent tumors can be explained by adjuvant chemotherapy suppressing tumor growth.

Predictive Biomarkers of Pathological Response to Neoadjuvant Chemoradiotherapy for Locally Advanced Soft Tissue Sarcomas

“…CD31 was also indicated to play a significant role in immune cell adhesion and integrin activation [53]. At the same time, CD34-an endothelial cell marker-is also considered as one of the main activators of angiogenesis in sarcomas, including sarcoma recurrence [54]. In a sarcoma study, median CD34 based IMVD was 44.6 for Ewing's sarcoma, 39.7 for osteosarcomas, and 12.9 for chondrosarcomas [55].…”