NFKB1 and breast cancer: Downstream mediators linked to LYN activation of NFκB include MEK, IKKα (or CHUK) (Cooper et al., 2013), PI3K (Toubiana et al., 2015), MAPK and IκB (Avila et al., 2012), and there is also support for a role of NFκB activation in BRCA1 loss-of-function-associated breast cancers.