Angiogenesis, the formation of blood and lymphatic vessels, is regulated by different pro- and anti-angiogenic molecules. The balance between pro- and anti-angiogenic molecules determines the outcome between vessel growth and vessel regression. In the skin, angiogenesis reprents a pivotal step during physiology (wound healing, hair cylce) and pathology (tumor growth and metastasis, psoriasis vulgaris). Therefore, a better knowledge of angiogenesis of the skin will improve the understanding of different dermatological diseases and hopefully increase efficacy of skin therapy.

The junior research group „Vascular Tumormicroenvironment“ studies the vascular network in different skin tumors as malignant melanomas, squamous cell carcinomas of the skin and primary cutaneous lymphomas. The group analysis the role of different pro- and anti-angiogenic molecules during skin tumor development and metastasis formation. Furthermore, we decipher the relevance of the interaction between vascular cells (endothelial cells, pericytes) and non-vascular cells (tumor cells, cancer-associated fibroblasts, lymphocytes) in skin tumors.

The current work aims to unravel

• the mechanims which decide if an angiogenic molecules acts pro- or anti-angiogenic
• which pro- and anti-angiogenic molecules are important for primary cutaneous T-cell lymphomas
• the role of angiogenic molecules for non-vascular cells in different skin tumor models (malignant melanomas, squamous cell carcinomas of the skin)

1. Teichert M, Stumpf C, Booken N, Wobser M, Nashan D, Hallermann C, Mogler C, Müller CS, Becker JC, Moritz RK, Andrulis M, Nicolay JP, Goerdt S, Thomas M, Klemke CD, Augustin HG, Felcht M: Aggressive primary cutaneous B-cell lymphomas show increased Angiopoietin-2-induced angiogenesis. Exp Dermatol. 24:424-9, 2015.
2. Mrotzek C, Felcht M, Sommer A, Schrader A, Klemke CD, Herling M, Schlaak M, Fabri M: Vitamin D controls apoptosis and proliferation of cutaneous T cell lymphoma cells. Exp Dermatol. in press, 2015.
3. Klemke CD, Booken N, Weiss C, Nicolay JP, Goerdt S, Felcht M, Géraud C, Kempf W, Assaf C, Ortonne N, Batistella M, Bagot M, Knobler R, Quaglino P, Arheiliger B, Santucci M, Jansen P, Vermeer MH, Willemze R. Histopathologic and immunophenotypical criteria for the diagnosis of Sézary syndrome in differentiation from other erythrodermic skin diseases: An EORTC Cutaneous Lymphoma Task Force Study of 97 cases. Brit J Dermatol. in press, 2015.
4. Felcht M, Thomas: Angiogenesis in malignant melanoma. J Dtsch Dermatol Ges. 13: 125-36, 2015.
5. Felcht M, R Luck, A Schering, P Seidel, K Srivastava, J Hu, A Bartol, Y Kienast, C Vettel, EK Loos, S Kutschera, S Bartels, S Appak, E Besemfelder, D Terhardt, E Chavakis, T Wieland, C Klein, M Thomas, A Uemura, S Goerdt, HG Augustin: Angiopoietin-2 differentially regulates angiogenesis through TIE2 and integrin signaling. J Clin Invest 122: 1991-2005, 2012.
6. Felcht M,* Heck M,* Weiss C, Becker JC, Dippel E, Müller CS, Nashan D, Sachse MM, Nicolay J, Booken N, Goerdt S, Klemke CD: Expression of the T-cell regulatory marker FOXP3 in primary cutaneous large B-cell lymphoma tumor cells.Brit J Dermatol 167: 348-58, 2012. [*authors contributed equally]
7. Felcht M, Klemke CD: Diagnstic criteria for primary cutaneous B-cell lymphomas. Akt Dermatol 37: 199-205, 2011.
8. Felcht M, Booken N, Ströbel P, Goerdt S, Klemke CD: The value of molecular diagnostics in primary cutaneous B-cell lymphomas in the context of clinic, histology and immunohistochemistry. J Am Acad Dermatol 25: 788-93; 2011.
9. Thomas M*, Felcht M*, Kruse K, Kretschmer S, Deppermann C, Biesdorf A, Rohr K, Benest AV, Fiedler U, Augustin HG: Angiopoietin-2 stimulation of endothelial cells induces avß3 integrin internalization and degradation. J Biol Chem 285: 23842-9, 2010. [*authors contributed equally]
10. Booken N, Utikal J, Felcht M, Weiß C, Goerdt S, Klemke CD: Extracorporeal photopheresis in the management of cutaneous T-cell lymphoma: Results of an uncontrolled retrospective study in comparison with the literature. J Dtsch Dermatol Ges 8:428-38, 2010.