Upregulation of vascular endothelial growth factor (VEGF) and downregulation of placenta growth factor (PlGF) associated with malignancy in human thyroid tumors and cell lines.
We show that one of the most commonly encountered genetic changes detected in human cancer, i.e., expression of mutant ras oncogenes, is associated with marked up-regulation of VEGF/VPF in transformed epithelial cells.
Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), plays an important role in the increased vascular permeability and angiogenesis associated with many malignant tumors.
VPF/VEGF mRNA and protein were expressed by the neoplastic cells in all of the malignant tumors evaluated, with the majority of tumors (28 of 29) showing strong expression of mRNA.
The present study shows that insulin-like growth factor 1 (IGF-I), a mitogen that promotes the propagation of cancers through autocrine and paracrine mechanisms, increases the expression of mRNA for VEGF and production of VEGF protein by COLO 205 colon carcinoma cells.
These mechanisms may be of importance in the pathogenesis of healing wounds and some malignant tumors that are commonly characterized by hypoxia and overexpression of VPF/VEGF.
Mutation or loss of function of the von Hippel-Lindau (VHL) tumor suppressor gene is regularly found in sporadic renal cell carcinomas (RCC), well vascularized malignant tumors that characteristically overexpress vascular permeability factor/vascular endothelial growth factor (VPF/VEGF).
We studied isoform pattern (VEGF206, VEGF189, VEGF165, VEGF121) of an angiogenic factor VEGF in both esophageal primary cancers and cancer xenografts by RT-PCR analysis.
We have previously demonstrated that vascular endothelial growth factor-165 (VEGF), a tumor-secreted angiogenic factor, can acutely and chronically induce fenestrations in microvascular endothelium (Cancer Res 1997, 57:765-772).
8-Cl-cAMP treatment caused in the three cancer cell lines a significant dose- and time-dependent inhibition in the expression of various endogenous autocrine growth factors, such as transforming growth factor alpha, amphiregulin, and CRIPTO, and of two angiogenic factors, such as vascular endothelial growth factor and basic fibroblast growth factor, at both the mRNA and protein levels.
Because neoangiogenesis represents an important prognostic indicator of poor prognosis in non-small cell lung cancer (NSCLC), we investigated the influence of VEGF during progression of this type of cancer and its relationship to tumoral neovascularization.
Because of VEGF's central importance for pathophysiological angiogenesis, the development of antagonists for VEGF in the treatment of cancer, and the use of VEGF therapeutically in cardiovascular diseases are now the focus of major research efforts.
In non-small cell lung carcinoma (NSCLC), neoangiogenesis, p53 alterations, and VEGF expression seem to have meaningful implications in the development and progression of this type of cancer.
Vascular endothelial growth factor (VEGF) protein expression has shown to be strictly associated with neovascularization both in human cancer and in various type of preinvasive lesions.
Estrogen and androgen induction of VEGF expression and promotion of new vessel formation may be an important paracrine mechanism by which these hormones contribute to the early phase of tumor growth of hormonal cancer.
An immunohistochemical analysis with antibodies to 4E, VEGF, and basic (b)-FGF was performed on 115 specimens of the head and neck representing various stages of histological progression of malignancy.
Although the mechanism on the induction of VEGF gene is still unclear in human cancer tissue, we obtained the informative evidence indicating that p53 mutation is involved in VEGF expression of esophageal cancer.
VEGF overexpression occurs in most human malignancies including thyroid carcinomas in which elevated VEGF expression is associated with a high tumorigenic potential.
The low frequency of VEGF expression amongst MSI-H cancers may partially explain why these cancers are less aggressive, with a better overall prognosis.