Development of a liquid overlay-based three-dimensional cell culture panel for drug screening applications.

3D cell culture has emerged as a relevant and promising alternative model for improving the preclinical phase of pharmaceutical development. It mimics cell-cell and cell-matrix interactions, as well as drug penetration and toxicity responses. However, there are currently no standardized methods that could lead to highly predictive treatment responses. In this context, the focus of this study was the adaptation of a liquid overlay technique, to generate a large and reproducible panel of six spheroid models, including melanoma, small cell lung cancer, non-small cell lung cancer, ovarian cancer, non-tumorigenic breast tissue and healthy kidney tissue. In this way, four cell concentrations (200 to 10,000 cells per well) with four matrix percentages (0 to 3%) were tested to determine the optimal combination based on their compaction, proliferation and viability. The surface characterization of each model was then assessed using scanning electron microscopy. Afterwards, the cytostatic and cytotoxic responses of these models to three targeted anti-PARP therapies, Olaparib, Rucaparib and Niraparib, were analyzed, revealing their sensitivity. These results demonstrated that our liquid overlay-based technique provides both a large cell culture panel, whatever the tissue type or pathological level, and an automated drug screening process that could lead to highly predictive efficacy results.