Fatty Acid Ratios as Parameters to Discriminate Between Normal and Tumoral Cells and Compare Drug Treatments in Cancer Cells

The fatty acid (FA) composition of cell membranes represents a metabolic biomarker. However, the FA profile reproducibility in cell cultures remains a significant challenge. In this study, cell FA ratios are validated as metabolic markers alternative to cell FA. To this goal, cell samples belonging to cancer HeLa cells and normal 3T3 fibroblasts, from various experimental sets, are analyzed by a high-performance liquid chromatography system coupled with a photodiode array detector and evaporative light scattering detector (HPLC-DAD/ELSD), and the ratios among the main FA are calculated. Principal component analysis (PCA) separately performed on FA and FA ratio data indicates similar clustering of cell samples concerning the cell type. Moreover, similar scores values t[1] and t[2] and graphical distances are calculated in the PCA plots separately performed on FA and FA ratios measured in cancer HeLa cells subjected to various antitumoral compounds. Last, PCA applied to selected FA ratios measured in various cell lines, obtained in similar experimental conditions, allows to discriminate between normal and tumoral cells. The results substantiate FA ratios as a cell-specific fingerprint, characterized by reproducibility across intra-laboratory conditions, useful for cell characterization, discrimination between normal and tumoral cells, and the comparison of different drug treatments. Practical Applications: The reproducibility of the fatty acid (FA) profile in cell cultures remains a significant challenge. Results obtained from this study improve knowledge about the role of the FA ratio profile as a cell-specific fingerprint characterized by reproducibility across intra-laboratory conditions. The characterization of the specific FA ratio profile of a cell culture, under standardized experimental conditions, can facilitate the comparative evaluation of cell data sets for nutritional, metabolic, and pharmacological studies, overcoming differences in cell culture conditions and FA extraction/analytical procedures.