tokens: Both 468 . siMUC1 and BT . siMUC1 also showed reduced activation of ERK1 / 2 ( dpERK1 / 2 ; 0 . 21 and 0 . 27 relative to siLuc , respectively ) , as would be expected with diminished signaling through MEK1 / 2 ; total ERK1 / 2 levels remain unchanged .