A multidimensional impedance platform for the real-time analysis of single and combination drug pharmacology in patient-derived viable melanoma models.

In today's development of anticancer drugs, there is an enormous demand for sensitive, non-invasive real-time screening technologies to identify pharmacodynamics/-kinetics of single and combined drugs with high precision. The combination of sophisticated drug sensitivity testing with advanced in vitro tumor models reflecting heterogeneous tumor behavior in vivo is needed to more reasonably predict therapeutic outcome in vivo. In this study, the benefits of our real-time, non-invasive multidimensional impedance platform over standard in vitro drug sensitivity assays were demonstrated quantitatively using an advanced melanoma model. Detailed pharmacological profiles of clinically established targeted therapeutics in single and combination treatment have been identified in patient tissue and isolated 2D/3D cell line cultures. Impedance spectroscopy revealed significant differences in tissue structure responsible for BRAF inhibitor pharmacokinetics in BRAF tumor microfragments and cell lines. Remarkably, BRAF-/MEK inhibitor combination treatment of direct patient-derived tissue, but not melanoma cell lines, resulted in short-term antagonistic effects consistent with in vivo findings. In contrast, the clinically validated resistance delay and thus long-term synergy of targeted therapeutics in advanced melanoma models has been demonstrated using impedance technology. The results demonstrate limited clinical transferability of 2D/3D cancer cell line-based chemosensitivity data and underline the importance of in vivo-like direct patient-derived tissue for predictive drug studies. Our non-invasive and highly sensitive multidimensional impedance platform offers great potential for quantifying short- and long-term drug kinetics and synergies to identify the most effective drug combinations in advanced cancer models, thereby improving personalized drug development and treatment planning and ultimately, overall patient outcomes.