MMP1 and cancer: Our recently study has suggested that, under conditions of DR5 suppression, available FADD and caspase-8 may recruit and stabilize tumor necrosis factor receptor-associated factor 2 (TRAF2), resulting in the activation of ERK and JNK signaling and subsequent AP-1-dependent expression and activation of MMPs (e.g., MMP1) and final promotion of invasion and metastasis of cancer cells [11].