Abstract 328: Original microenvironment of different cancer types is maintained upon culture of primary tissues in perfused bioreactors
Authors: Hirt Christian , Muraro Manuele G. , Mele Valentina , Amicarella Francesca , Manfredonia Celeste , Soysal Savas D. , Muenst Simone , Mariani Luigi , Kettelhack Christoph , Heberer Michael , Spagnoli Giulio C. , Martin Ivan , Iezzi Giandomenica , Papadimitropoulos Adam 
Published: August 2015

Abstract
The development of novel three-dimensional (3D) culture systems allowing the survival/expansion of primary tumors in vitro may help to bridge the gap between conventional bi-dimensional (2D) cultures and animal models, poorly predictive of therapeutic responses.
We have investigated the suitability of a previously developed perfused bioreactor system for the in vitro culture of human primary tumor tissues.
Surgical specimens of colorectal cancer (CRC, n = 15), glioblastoma (n = 3), breast cancer (n = 3), sarcoma (n = 2), and melanoma (n = 1) were used. Tumor fragments, obtained upon mechanical mincing and enzymatic digestion, were cultured on collagen scaffolds, in medium supplemented with human serum, under alternate perfusion up to 20 days. Characterization of expanded tissues was performed by histo-morphological analysis, immunofluorescence and gene expression profiling.
CRC tissues were effectively expanded in perfused 3D cultures in 10 out of 15 cases, whereas no expansion was observed under static culture conditions. Gene profiles of expanded tumor tissues suggested a heterogeneous tissue composition, as indicated by the expression of EpCAM, CD90, CD8, CD16 and Foxp3 genes. Phenotypic analysis confirmed that expanded tissues included epithelial and stromal cells, as assessed by EpCAM and vimentin staining, respectively. Evidence of tumor cell proliferation was provided by Ki67 staining. Furthermore, infiltrating CD4+ and CD8+ lymphocytes were consistently identified within cultured tumor fragments.
The established protocol could easily be adapted to other tumor types, including breast-cancer, glioblastoma, sarcoma and melanoma, with highly effective tissue formation.
Taken together, our results indicate that culture of primary tumor fragments within perfused bioreactors can be successfully achieved over a short-time period in a reproducible manner, and results in the expansion of epithelial and interstitial cells. These ex-vivo generated tissues might mirror features of the original tumor more effectively than 2D or 3D static cultures, and of patient-derived xenografts, thus possibly representing useful tools for the evaluation of sensitivity to chemotherapies or new targeted treatments.
Citation Format: Christian Hirt, Manuele G. Muraro, Valentina Mele, Francesca Amicarella, Celeste Manfredonia, Savas D. Soysal, Simone Muenst, Luigi Mariani, Christoph Kettelhack, Michael Heberer, Giulio C. Spagnoli, Ivan Martin, Giandomenica Iezzi, Adam Papadimitropoulos. Original microenvironment of different cancer types is maintained upon culture of primary tissues in perfused bioreactors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 328. doi:10.1158/1538-7445.AM2015-328