JNK activation in HSCs in response to TGF-β and platelet-derived growth factor (PDGF) activates Smad2/3 leading to α-smooth muscle actin (αSMA) expression, migration of resident HSCs and myofibroblasts, and fibrosis in NASH [17]. The gene discussed is MAPK8; the disease is metabolic dysfunction-associated steatohepatitis.