Tumor Cell Microenvironment and Microvessel Density Analysis in MALT Type Lymphoma.

Background/aim: MALT type lymphoma belongs to marginal zone lymphoma (MZL). MALT lymphomas' inflammatory microenvironment contributes to the pathogenesis of this cancer. In this study, we analyzed and quantified the tumor inflammatory microenvironment in MALT lymphoma samples and in healthy controls, and the microvessel content by immunohistochemistry and morphometric estimation.

α-Methyl-prednisolone normalizes the PKC mediated brain angiogenesis in dystrophic mdx mice.

A fraction of patients affected by Duchenne Muscular Dystrophy (DMD) shows mental disability as a consequence of neuronal and metabolic alteration. In this study, we evaluated the effect of α-methyl-prednisolone (PDN) on the expression of the angiogenic marker HIF1α, VEGFA and VEGFR-2 (FLK1) in correlation with PKC expression in the brain of mdx mouse, an experimental model of DMD. We demonstrated that HIF1α, VEGFA and FLK1 are overexpressed in the brain of dystrophic mdx mice in parallel with an increase of PKC expression and reduction of the tight junctions Occludin leading to altered angiogenesis.

Angiogenic activity of multiple myeloma endothelial cells in vivo in the chick embryo chorioallantoic membrane assay is associated to a down-regulation in the expression of endogenous endostatin.

We have attempted a fine characterization of the angiogenic response induced by multiple myeloma endothelial cells (MMEC) by using the chick embryo chorioallantoic membrane (CAM) assay and by reverse transcriptase-polymerase chain reaction (RT-PCR). Results showed that in the CAM assay MMEC induced an angiogenic response comparable to that of a well-known angiogenic cytokine, namely fibroblast growth factor-2 (FGF-2), while RT-PCR demonstrated that the expression of endostatin mRNA detected in MM treated CAM was significantly lower respect to control CAM. These data suggest that angiogenic switch in MM may involve loss of an endogenous angiogenesis inhibitor, such as endostatin.

HIF activation and VEGF overexpression are coupled with ZO-1 up-phosphorylation in the brain of dystrophic mdx mouse.

In Duchenne muscular dystrophy (DMD) metabolic and structural alterations of the central nervous system are described. Here, we investigated in the brain of 10 mdx mice and in five control ones, the expression of hypoxia inducible factor-1alpha (HIF-1alpha) and we correlated it with the expression of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-2 (VEGFR-2) and of the endothelial tight junction proteins zonula occludens-1 (ZO-1) and claudin-1. Results showed an activation of mRNA HIF-1alpha by reverse transcription polymerase chain reaction (RT-PCR) and a strong HIF1-alpha labeling of perivascular glial cells and cortical neurons by immunohistochemistry, in mdx mouse.

Neovascularization and mast cells with tryptase activity increase simultaneously in human pterygium.

Mast cells (MC) have been implicated in both normal and pathological angiogenesis, such as that in chronic inflammatory diseases and tumors. This assumption is partially supported by the close structural association between MC and blood vessels and the recruitment of these cells during tumor growth. MC release a number of angiogenic factors among which tryptase, a serine protease stored in MC granules, is one of the most active.

Desmin-positive pericytes in the chick embryo chorioallantoic membrane in response to fibroblast growth factor-2.

Pericytes stabilize vessel wall, participate in the regulation of blood flow microcirculation and influence endothelial proliferation, survival, migration and maturation. Pericytes are commonly identified by molecular markers, such as desmin. The aim of this study was to analyze the pattern of distribution of desmin in the chick embryo chorioallantoic membrane (CAM) vasculature in normal condition and in response to an angiogenic cytokine, such as fibroblast growth factor-2 (FGF-2) by using conventional immunohistochemistry and confocal laser scanning microscopy.

Vascular endothelial growth factor-A, vascular endothelial growth factor receptor-2 and angiopoietin-2 expression in the mouse choroid plexuses.

In this study, for the first time, we investigated about the localization of VEGF-A, VEGFR-2 and Ang-2 in the choroid plexuses of the adult mouse by Western blot and immunohistochemistry. Results showed that VEGF-A stained epithelial cells, while anti-VEGFR-2 and -Ang-2 antibodies stained endothelial cells. These data suggest that Ang-2, converting blood vessels into a more plastic and immature phenotype, would provide more accessibility of VEGF-A to endothelial cells.

Aquaporin-1 expression in the chick embryo chorioallantoic membrane.

The chick embryo chorioallantoic membrane (CAM) is commonly used in vivo to study both angiogenesis and anti-angiogenesis. Rapid membrane water transport is mediated by a family of molecular water channels, called aquaporins (AQPs), which have been identified in the epithelial and endothelial cells of higher vertebrates. AQP1, expressed in adsorptive and secretory epithelia, is also expressed in endothelial cells of capillaries and arteries.