Phosphospecificity: Whole cell extracts of control (lane 1), EGF stim ulated (lane 2) or pervanadate treated (lane 3) SKOV3 tumor cells were applied to SDS-PAGE (ca 20.000 cells per lane) and transferred to a PVDF membrane. The immunoblot was probed with mab 11E6 (0.5 ug/ ml) for 1h at RT and developed by ECL (exp.time: 30 sec).