MAP2K1 and liver dysplastic nodule: miR-378 suppresses apoptosis of podocytes through TRAF5 and thereby represses diabetic nephropathy (DN) progression, and it also regulates the protective function of mitogen-activated protein kinase 1 (MAPK1) in the stimulation of kidney cell fibrosis, as well as mesangial hypertrophy [23, 24].