Conclusions

Tumor angiogenesis and tumor growth are accompanied by only a transient increase in platelet rolling in angiogenic microvessels in close vicinity to tumor cells. This might be due to endothelial stimulation by growth factors and cytokines released partly from tumor cells. Within tumor microcirculation, adhesion molecules mediating platelet-endothelial interactions appeared to be downregulated or even absent. Platelet-endothelial interaction in response to endothelial stimulation was significantly reduced in tumor microcirculation.

Future studies are needed to identify mechanisms regulating adhesion molecule expression in tumor microcirculation. Further attempts should focus on induction of platelet aggregation by selective transport of prothrombotic agents into the tumor microcirculation. The results might provide further therapeutic aspects in targeting tumor angiogenesis.

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Capsule Biography

Dr. Dellian has been leading a research laboratory on tumor microcirculation and angiogenesis at the Institute for Surgical Research, University of Munich, since 1995. He was introduced to his research by the pioneers in tumor microcirculation, Prof. Konrad Messmer, Prof. Alwin Goetz, and Prof. Rakesh Jain.

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