Raised levels of latent collagenase activating angiogenesis factor (ESAF) are present in actively growing human intracranial tumours

Abstract

Endothelial cell stimulating angiogenesis factor (ESAF) is a potent, low molecular mass mitogen, specific for endothelial cells. In common with various protein growth factors, it displays angiogenic activity in a variety of biological test systems. However, it differs from these other factors by virtue of its low molecular mass and its ability to activate latent matrix metalloproteinases in a dose dependent manner. This activity has been used to quantify the factor in both normal and diseased brain tissue. The concentration of ESAF determined in biopsies from different types of intracranial tumours varied: in some tumour types the level was close to that of control samples whereas in others it rose to levels comparable to those encountered in the pineal gland, the richest source of ESAF in mature mammals. Tumours considered to be benign contained significantly less ESAF than those neoplasms classified as being malignant (P = 0.025). There was also a correlation between the mitotic activity of tumour samples, as determined by conventional H & E histochemical staining and the ESAF concentration present. These findings agree with previous studies in which elevated ESAF levels have been found in tissue where proliferation of vascular elements has been observed. Images Figure 1

Immunohistochemical Demonstration of Vascular Endothelial Growth Factor in Vestibular Schwannomas Correlates to Tumor Growth Rate

“… 1,32,33 This knowledge is a strong indication of a probable role of angiogenic growth factors in expanding vestibular schwannomas, so far only demonstrated biochemically by the presence of endothelial cell stimulating angiogenesis factor in four tumors. 34 In an immunohistochemical investigation, Maurer et al . 35 demonstrated VEGF reactivity in only 1 of 34 vestibular schwannomas.…”

Expression neurotropher Faktoren im Vestibularisschwannom - eine Übersicht

“…Die biologische Bedeutung von angiogenen Faktoren für das VS wurde bereits 1991 von Taylor u. Mitarb. [55] diskutiert, die in verschiedenen intrakraniellen Tumoren erhöhte Werte für den Endothelial Cell Stimulating Angiogenesis Factor (ESAF) fanden. Auch die Expression von VEGF und dessen Rezeptor VEGFR-1 im VS wurde in den letzten Jahren intensiv untersucht und ist mittlerweile durch verschiedene Arbeitsgruppen demonstriert worden [56,57].…”

Suppression of matrix metalloproteinase-2-mediated cell invasion in U87MG, human glioma cells by anti-microtubule agent: in vitro study

“…extracellular matrix toward the source of the angiogenic stimulus. The induction of this endothelial cell migration requires the presence of MMPs (Taylor et al, 1991). Vaithilingam has reported an increase in the activity of general proteinases and type IV collagenases (MMP-2 and -9) in the serum, associated with the growth of C6 rat glioma cells in a spheroid implantation model (Vaithilingam et al, 1992).…”