(102d) Studying the Effects of Sphingolipid Metabolites On Cells' Dielectrophoretic Properties Using Contactless Dielectrophoresis

Current conventional cancer treatment regimens often rely upon toxic chemotherapeutics or target oncogenes that are variably expressed within the heterogeneous cell population of tumors. These challenges highlight the need for novel treatment strategies that can act on cells independently of variably expressed biomarkers and are non-toxic yet able to at least partially reverse the aggressive phenotype of the disease to a benign or very slow-growing state. To investigate the effect of non-toxic concentrations of sphingosine, a tumor-suppressor metabolite, and sphingosine-1-phosphate, a tumor-promoter metabolite, on the intrinsic electrical properties of mouse ovarian surface epithelial (MOSE) cancer cells, we used a label-independent rapid microfluidic cell manipulation platform known as contactless dielectrophoresis (cDEP). cDEP uses microfluidic electrode channels to provide a non-uniform electric field, avoiding direct contact between metal electrodes and the sample traditionally required by DEP. This contactless method eliminates electrochemical contamination, extensive sample preparation (no antibody labeling), and can maintain sterility of the sample. Previously, we used cDEP to demonstrate that electrical properties change as MOSE cells progress from a benign early stage (MOSE-E) to later malignant stages. Here, we demonstrate an association between So treatment and a shift in the bioelectrical traits of late stage MOSE (MOSE-L) cells towards a profile similar to that of benign MOSE-E cells. The specific membrane capacitance of MOSE-L cells shifted toward that of MOSE-E cells, decreasing from 23.94±2.75 to 16.46±0.62 mF/m² after So treatment. In contrast, S1P did not reverse the electrical properties of MOSE-L cells. This work demonstrates the potential for this microfluidic cDEP platform to be used as a new, rapid technique for drug efficacy studies, and eventually designing more personalized treatment regimens.