Abstract C116: Phenotypic strategies for anticancer drug discovery

Abstract

Abstract Although recent innovations in anti-cancer therapies have led to better treatment strategies and improved patient outcomes, cancer is still one of the leading causes of morbidity and mortality, globally. Thus, the need to pursue better and safer therapies remains as critical and compelling as ever. Improving and streamlining drug development efforts in this area will expedite the progress already made in offering new treatment modalities for cancer patients. By incorporating more translational, predictive approaches earlier in the drug discovery pipeline, we can enable the identification of more efficacious and safer pre-clinical candidates to advance to the clinic. Eurofins Discovery BioMAP® (CRC) Oncology Panel models human tumor-immune microenvironment (TME) biology in vitro by co-culturing host stromal or vascular cell types with PBMC and the HT-29 human tumor cell line. Standard assay readouts include 42 protein biomarkers that inform on a test agent’s impact on the complex TME co-culture. We sought to expand these models to include a measure of cancer cell-specific killing relevant for clinical efficacy. Briefly, we screened a select number of reference compounds on a set of ≥240 cancer cell lines (including HT-29) available in the OncoPanel™ assay in order to select agents and concentrations specific for direct HT-29 killing. The HT-29 cells were then pre-loaded with a cell membrane-penetrant fluorescent dye, and incorporation was verified by flow cytometry. Labelled HT-29 cells were then added to a fibroblast/PBMC or HuVEC/PBMC co-culture, and the assay was performed according to our standard protocol. Briefly, test agent addition was followed by stimulation to recapitulate immune activation relevant for the TME. After 48 hours, protein-based biomarkers were measured via ELISA or electrochemiluminescence, and cancer cell death was visualized by high-content imaging. Imaging of the fluorescently-labeled HT-29 cells showed zero transfer of the dye to the host cell types present in the systems. Additionally, the TME biomarker profiles were unaffected by the incorporation of the dye into the HT-29 cells. Profiling test agents in the OncoPanel assay allows for rapid stratification of cancer cell types for sensitivity. Subsequent profiling in BioMAP Oncology systems allows for assessment of test agent impacts on the physiologically relevant TME. Here we demonstrate the ability to detect cancer cell viability within the context of the TME, either by direct action of the anti-cancer agent or indirectly via the immune-restorative effects of a test agent relevant for immune-oncology therapies. These translational assays can enable the fast and effective prioritization of test agents based on concurrent assessment of efficacy and safety towards better clinical candidates and improved patient outcomes. Citation Format: Steven M. Garner, Alyssa M. Croff, Justin H. Lipner, Alison O'Mahony, Sharlene Velichko, Alastair J. King, Jesse J. Parry. Phenotypic strategies for anticancer drug discovery [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C116. doi:10.1158/1535-7163.TARG-19-C116