Neue pathogenetische Aspekte beim Merkelzellkarzinom^[*]

Zusammenfassung

Die jüngsten Entwicklungen zur Pathogenese des Merkelzellkarzinoms haben unser Verständnis für diesen Tumor beträchtlich verbessert. Die klonale Integration des Merkelzell(polyom)virus ins Genom der Tumorzellen und die tumorspezifische verkürzende Mutation des LT-Antigens während der Integration ist dabei der wesentliche Mechanismus, der zur Entartung der Zellen führt. Weitere Ereignisse tragen offensichtlich zur Merkelzelltransformation bei, wie die simultane Expression des Stammzellfaktors und seines Rezeptors KIT, was eine autokrine Förderung des Zellwachstums bewirkt.

Abstract

Recent developments on Merkel cell carcinoma pathogenesis have substantially improved our understanding for this tumor. The clonal integration of the Merkel cell (polyoma) virus in the genome of the tumor cells and the tumor specific truncating mutation of the LT antigen during integration represent a major mechanism for carcinogenesis. Additional events apparently contribute to Merkel cell transformation, such as the simultaneous expression of stem cell factor and his receptor KIT resulting in an autocrine stimulation of cell growth.

^* Nach einem Vortrag anlässlich des 11. Jahressymposions der Berliner Stiftung für Dermatologie am 2. Juli 2011, Berlin.

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