DDR2 and neoplasm: DDR1 and DDR2 have key implications in cell survival, growth and adhesion/migration via the downstream signaling through Ras/Raf/MAPK, PI3K/Akt/NFκB, JAK/STAT and Rho pathways.456 Rac/JNK, PI3K/Akt and Ras/Raf/MEK/ERK1/2 pathways are also regulated by the RET receptor signaling which is responsible for an enhanced proliferation and differentiation in normal and tumor cells.457,458