Abstract
Vascular endothelial growth factors are the most powerful molecules related to angiogenesis and lymph angiogenesis stimulation and are frequently associated to a worse prognosis in many malignancies. Currently, anti-angiogenic VEGF-A165b has been described and it have been demonstrated to efficiently block the angiogenic sprout. We sought to investigate the VEGF family members expression involved with angiogenesis (including the anti-angiogenic VEGF-A165b) and lymph angiogenesis. The casuistic was composed by 196 cases. The frequencies of thyroid lesions were: 53 (27%) goitres, 16 (8%) thyroiditis, 9 (5%) follicular adenomas, 84 (43%) papillary carcinomas, and 34 (17%) follicular carcinomas. The immunohistochemical reactions for VEGF-A, VEGF-A165b, VEGF-B, VEGF-C and VEGF-D were performed and semi-quantitatively assessed. We observed a widespread positive immunoexpression of VEGF-A and VEGF-A165b in benign and malignant lesions. None of the benign samples of this casuistic had positive immunoexpression of VEGF-B and only a few positive cases were detected in both papillary and follicular carcinomas. The highest levels of VEGF-C and VEGF-D expression were found in papillary carcinomas. There was a relevant association of VEGF-D and a worst tumoral staging (p=0.004) in papillary carcinomas. We also identified a significant association between VEGF-A and vascular invasion (p=0.049) and patient’s age and an increased expression of VEGF-B (p=0.047) in papillary thyroid carcinomas. No association was found for follicular carcinomas.
Highlights
The regulation of vasculogenesis, haematopoiesis, angiogenesis, lymph angiogenesis and vascular permeability are very complex
The VEGFR-1 binds to VEGF-A and-B, VEGFR-2 binds to VEGF-A, -C and-D and VEGFR-3 binds to VEGF-C and - D [6,7]
The objective of the present study was to determine the immunohistochemical expression of pro-angiogenic vascular endothelial growth factors VEGF-A, VEGF-B, VEGF-C and VEGF-D, and his anti-angiogenic variant VEGF-A165b in a series of malignant and benign thyroid lesions and correlate their expressions with the clinicopathological data
Summary
The regulation of vasculogenesis, haematopoiesis, angiogenesis, lymph angiogenesis and vascular permeability are very complex. Several molecules, such as the family of VEGFs (vascular endothelial growth factors) and other growth factors have been described as important regulators of tumour angiogenesis and lymph angiogenesis, and are considered important therapeutic targets [1,2]. The family of VEGFs comprises a group of highly conserved factors regulating vasculogenesis, haematopoiesis, angiogenesis, lymph angiogenesis and vascular permeability [5,6]. The VEGF family members in mammals comprise VEGF-A, VEGF-B, VEGF-C, VEGF-D and placental growth factor (PlGF). These glycoproteins belong to a super family of factors that include platelet-derived growth factor (PDGF). Neuropilin - 1 (NP-1) and Neuropilin - 2 (NP-2) are co-receptors for some VEGF isoforms and subtypes [7]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have