Fig. 1

The transformation status affected the metabolic profile of mesothelial cells at steady state and after pemetrexed (pem) treatment. Mass spectrometry-based analysis of extracellular metabolites. A. PCA plot illustrating the distribution of human mesothelial untransformed cells (HMC, from 4 healthy donors) and of three mesothelioma (MPM) cell lines after ctrl (saline)-treatment for 24 h B. PCA plot showing the distribution of the same cell cultures after a short pulse of both ctrl and pemetrexed (pem) at a clinically relevant dose (see text, please). C. Representative box plots of three classes of metabolites selected because modulated in 3/3 MPM cell lines and unchanged in the HMC cultures after pem treatment. Upper panel: thymine (left) and uracil (right). Middle panel: glucose (left) and lactate (right). Lower panel: glutamine (left) and leucine (right). Please note that “ctrl” refers to spent media at 24 h in absence of cells (see methods please). Statistics: * p < 0.05. ns = not significant (p > 0.05)