On the other hand, targeting RAF1 with selective inhibitors synergizes with MEK inhibition in MSS CRC cell lines harboring a KRAS mutation [22], with a prominent role of RAF1, as also described in human colonosphere cultures in which genetic depletion of RAF1 impairs clonogenic and tumorigenic properties of CRC cells [23]. The gene discussed is MAP2K7; the disease is colorectal carcinoma.