This foundational review provides specific molecular details. It explicitly states that JNK2 and p38 MAPK activity are required for macrophage foam cell formation, a key immune event in atherosclerosis. It also details how ERK1/2, JNK1/2, and p38 MAPK are all required for vascular smooth muscle cell (VSMC) proliferation and neointima formation after vascular injury. For CMVD, this provides a detailed molecular basis for how MAPK signaling directly controls the behavior of key immune (macrophages) and structural (SMCs) cells involved in adverse vascular remodeling. Here, MAPK9 is linked to atherosclerosis.