NOTCH1 and B-cell chronic lymphocytic leukemia: Key signaling pathways for CLL have been identified on the basis of various gene mutations: In addition to BCR (CARD11, NFKBIE), TLR (MYD88) and MAPK (BRAF, RAS) receptor signaling, NOTCH (NOTCH1, FBXW7) and the non-canonical NF-kb signaling pathway (BIRC3, TRAF3) play an important role.