Transformation of the microvascular system during multistage tumorigenesis.

摘要: Simian virus SV40 large T Antigen expression in the islets of Langerhans transgenic mice results β-cell hyperproliferation, onset new blood vessel formation and development highly vascularized solid tumors. Angiogenesis RIPTag mouse model, as well human cancer, is a hallmark multistage tumorigenesis precedes In our study, intravital microscopy was used to monitor changes phenotype, microcirculation leukocyte adhesion during progression from normal angiogenic RIP1-Tag5 mice, an aberrant microangioarchitecture becomes apparent early stages spontaneous tumor development. Notably, transition characterized by increase diameter rather than numbers. Thus, dilatation existing vessels sprouting. Once initiated, neovascularization loss hierarchy differentiation. Solid insulinomas display higher density even more dramatic heterogeneity revealed local “hot spots” irregular diameters. Strikingly, profound are already observed suggesting that key features vasculature established prior expansion mass. Moreover, leukocytes found be dramatically decreased both tumors correlates with morphological alterations vasculature. transformation reduced leukocyte-endothelium interactions not exclusively but represent events tumorigenesis. © 2002 Wiley-Liss, Inc.