Abstract LB-211: Development of a standardized drug-testing platform using human primary tumor samples
Authors: Chris Kidd, Oke Ebenezer, Crystal Phillips, Kyle Lewter, Allen MacDonald, Dawn Adkins, Will Taylor, Obdulio Piloto
Journal: Cancer Research (2011)

Abstract In the past few years, various groups have demonstrated the role of tumor heterogeneity and the importance of using human primary cells, over established cell lines, to understand cell-cell, cell-extracellular matrix (ECM) and cell-drug interactions. In addition, access to an array of highly annotated, viable human primary samples that are processed in a standardized fashion is often the limiting factor for many academic and industry researchers. Building on these observations, we developed a standardized platform for collecting, processing and testing human primary samples (i.e. solid tumors, normal adjacent tissue, normal or diseased bone marrow/blood) from our network of clinical sites. Tumors were collected immediately after surgical resections and transported in HypoThermosol solution. Using our optimized protocols, these tumors were enzymatically and mechanically dissociated into single cells and cryopreserved in CryoStor media. The post-thaw viability of over 100 tumor samples, representing all major tumor types, was found to be 70–100% by Trypan blue exclusion. Flow cytometric characterization of these samples revealed that most samples contained 30–80% EpCAM+ (CD326+) cells, with colorectal tumors possessing the greatest percentage of EpCAM+ cells (60–80%). Further studies demonstrated that most human primary tumors contain &amp;lt;20% hematopoietic cells (CD45+/CD31−), &amp;lt;10% endothelial cells (CD31+/CD45−) and &amp;lt;10% putative cancer stem cells (CD326+/CD133+). A select group of patient samples with a high percentage of EpCAM+ cells was plated onto tissue-culture (TC) treated and Matrigel coated plates to assess their viability / proliferation over 6 days and their response to drug treatment. Most samples remained viable or proliferated during the 6-day study, yet some differences were observed between TC-treated and Matrigel coated plates. As expected, cells from different human primary tumors responded differently to a 3-day treatment with the tool compound staurosporine (8-point dose response). These studies also revealed that large assay windows (typically &amp;gt;50) are routinely observed using human primary cells. This assay is also reproducible, since similar dose-response curves were observed when human primary tumor cells were re-tested. In one example, cells from an ovarian metastatic tumor plated on Matrigel coated plates demonstrated slight resistance to staurosporine treatment compared to the same cells plated on TC-coated plates. In summary, our data highlights our efforts to optimize and standardize the collection and processing of human primary samples and the development of a drug-testing platform that is available to the research community. An array of different in vitro (i.e. tumor spheres, 3D culture, transwells, monocultures) and in vivo assay formats is currently being explored with our human primary samples, both from solid tumors and hematopoietic malignancies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-211. doi:10.1158/1538-7445.AM2011-LB-211