Paracrine activity of heparin-binding-EGF-like growth factor in atherogenesis: an immunohistochemical study

AIM: Cells involved in atherogenesis produce growth factors crucial for the progression of the atherosclerotic lesions. One of them is the heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor (EGF) family, synthesized as a transmembrane precursor (proHB-EGF). This anchored insoluble juxtacrine growth factor can be converted into a soluble molecule with paracrine activity and mature HB-EGF is released in the extracellular matrix from the cell surface. HB-EGF is a potent stimulator of cell proliferation, migration and cell motility and several studies show that HB-EGF is associated with pathologies of hyperplasia of smooth muscle cells including atherosclerosis.METHODS: We localized HB-EGF by immunohistochemistry within the atherosclerotic lesions collected from right or left internal carotid artery of 20 patients with evident clinical symptoms.RESULTS: In the 20 samples we tested, the proportion of positive samples was significant. Considering the only positive samples the proportion difference related to the gender of patients was highly significant.CONCLUSION: The aim of our investigation was to better understand if this growth factor exerts its role through a juxtacrine or paracrine mechanism, or both in the process of atherogenesis. According to the results, the paracrine role of HB-EGF was clear.