Abstract 4252: Establishment of a multicellular 3D cell culture model for tumor - endothelial cell interaction
Authors: Amann Arno , Zwierzina Marit , Kern Johann , Gamerith Gabriele , Koeck Stefan , Lorenz Edith , Rainer Johannes , Zwierzina Heinz 
Published: July 2016

Abstract
Introduction: Due to the increasing understanding of the mechanisms relevant to the genesis of cancer, we are experiencing a transition from disease to target-oriented therapy. One major hurdle for the development of these targeted therapeutic regimens, however, is the limited availability of predictive in vitro models. The critical challenge is to develop culture models better reflecting in vivo conditions. We present data that highlights the differences of RNA expression of in vivo like 3D microtissues consisting of tumour cells, fibroblasts and two different endothelial cell lines compared to normal 2D cell culture conditions.
Methods: 96-well hanging drop microtiter plates (InSphero AG, Zürich, Switzerland) were applied for the production of 3D mono-, co- and tri-cultures including the human lung cancer cell lines A549 or Colo699 alone or in combination with a human lung fibroblast cell line (SV-80) and either a human umbilical vein endothelial cell line (HUVEC) or the primary human lung microvascular endothelial cell line (HMVEC-L).
In addition, to conventional histology (H&E), tumour endothelial spheroid aggregation was displayed immunohistochemically (IHC) by protein expression of e-cadherin, CD31, von Willebrand factor (vWF) and α-muscle actin (α-SMA).
RNA expression profiling by Affymetrix chip analysis was performed for multicellular 3D microtissues and 2D cultured cell lines.
Results: Endothelial cells aggregated in coherent tube like structures preferentially in the fibroblast consisting core of all microtissues. Furthermore, endothelial cells expressed α-SMA only in microtissues that consisted both of fibroblasts and tumour cells indicating an interaction between these two cell types.
RNA expression profiles revealed a high number of regulated genes in tri-cultures when compared to microtissues only consisting of mono- or co-cultures or to traditional 2D cultivated cells. Regulated genes played an important role either in cell cycle, organelle fission, wound healing and DNA packing.
Interestingly, no difference in the RNA expression was displayed in microtissues containing either immortalized or primary endothelial cells,
Finally, a relation of RNA expression between our cell culture model and patient data was identified.
Conclusion: We demonstrate that cultivation of cells as multicellular microtissues in a 3D environment led not only to a difference in RNA but also in protein expression due to cell - cell interactions. Our data support the importance of performing complex co-culture for investigating tumour stroma interactions.
Citation Format: Arno Amann, Marit Zwierzina, Johann Kern, Gabriele Gamerith, Stefan Koeck, Edith Lorenz, Johannes Rainer, Heinz Zwierzina. Establishment of a multicellular 3D cell culture model for tumor - endothelial cell interaction. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4252.