The role of VEGF165B in pituitary adenomas pathogenesis

Abstract

Purpose. Inhibitory fraction of vascular endothelial growth factor (VEGF165b) in pituitary adenomas is also overexpressed, as a possible explanation of low microvascular density (MVD). Design and methods. For 86 retrospective cases of pituitary adenomas we established the histopathologic diagnosis by using morphological stains, followed by immunoprofile case selection and VEGF165b assessment. Results. A percentage of 16.66% of the studied cases had positive reaction to VEGF165b. The reaction was of low intensity in most of the cases, noted as +1 and in 7 cases we recorded moderate intensity reaction +2. Tumor cells that presented a granular cytoplasmic heterogeneous reaction, were noted as +1,+ 2 and +3 in relation to the number of tumor cells and the reaction intensity. In the areas of VEGF165b tumor positive, blood vessels were not observed. Instead, strongly positive cells for VEGF inhibitory fraction tended to enclose mature vessels with patent lumen. Conclusions. VEGF165b might have a role of angiogenesis inhibition in pituitary adenomas. The reduced percentage of VEGF165b positive cases also suggests the involvment of other mechanisms of angiogenesis inhibition.

Keywords

• VEGF165b
• pituitary adenomas
• angiogenesis inhibition.