MAPK3 and breast cancer: For example, when the BC cells MCF-7 and MDA-MB-231 and the adipocytes 3T3-L1 were co-cultured, the highly secreted exosomal microRNA-144 (miR-144) increased the development of CAAs by binding with mitogen-activated protein kinase kinase kinase 8 (MAP3K8), which lowered extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation and PPARγ levels to promote adipocyte dedifferentiation [24].