RRAS2 and neoplasm: Since this cell line derives from a tumor isolated in R26-RRAS2fl/fl x Wap-Cre mice and in these mice the human R-RAS2 is tagged at the N-terminus with an hemagglutinin (Hag) epitope [36], associated proteins could be recovered by immunoprecipitation with anti-Hag and identified by probing western blots with different antibodies.