METAP1 and cancer: We used a targeted mass spectrometry technique (selected reaction monitoring, SRM) to confirm this finding and to identify and quantify, with high levels of sensitivity and precision, the MetAP1 and MetAP2 proteins in three cell lines: the most sensitive cell line from cancer tissue (U87), the sensitive reference endothelial cell line (HUVEC) and a non-sensitive cell line (K562).