P2.03b-096 Utilization of a Novel 3D Culture Technology for the Assessment of Chemo-Resistance in Non-Small Cell Lung Cancer: Topic: Biomarkers

Elucidation of the key mechanisms underlying resistance to chemotherapy is an on-going and complex process. Owing to its suggested increased biological relevance, many are now transitioning from two-dimensional (2D) to three-dimensional (3D) cellular-based assay systems. These systems permit the formation of 3D multicellular structures (MCS). The internal micro-environment of these structures mimics closely those found in vivo. In addition they are considered to provide a more biologically relevant model of chemo-resistance. This study focuses on the utilization of a novel 3D culture technology to compare chemo-resistant models of non-small cell lung cancer (NSCLC) in 3D culture with those cultured in 2D monolayers. Critically, this will provide a valuable tool to determine the biological discrepancies which exist between the two culture methods with the aim to identify novel mechanisms of chemo-resistance in NSCLC. Isogenic NSCLC models of cisplatin resistance, which encompassed sensitive parent (PT) and matched cisplatin resistant (CisR) cell lines, were used for this study. The 3D MCS were cultured in Happy Cell Advanced Suspension Medium™ and 2D monolayers as standard. Both 2D and 3D cultures were exposed to a range of cisplatin concentrations (0 – 100 μM) for a period of 72 h. Subsequently, cellular viability, hypoxia, proteomic and morphological assays were conducted in order to compare the response of both PT and CisR cells in 2D and 3D. High content imaging has identified a central necrotic core within the 3D MCS, which is a feature of the asymmetric growth patterns observed in vivo; that being a decrease in viable cells as you move inwards from the periphery of the MCS. Preliminary data suggests that at equivalent cisplatin concentrations, H460 3D MCS exhibit increased resistance to cisplatin compared with 2D monolayers in both PT and CisR cell lines. Proteomic analysis has also identified diverse pathway modifications in 3D compared with 2D culture, with a number of proteins expressed exclusively in each. Additional cellular characterization and further bioinformatic analysis is on-going. Chemotherapeutic intervention is most frequently employed in the treatment of NSCLC, however many patients exhibit intrinsic and acquired resistance to common chemotherapy drugs, such as cisplatin and targeted agents. As it has been argued that 3D models and their micro-environment are more reflective of the in vivo situation, 3D culture may provide a more accurate in vitro model to elucidate mechanisms of chemo-resistance and possibly aid in the identification of novel targets to re-sensitize and stratify patients for therapy.