SMAD3 and carcinoma: According to these studies, Smad2 linker phosphorylation (on residues 245, 250 and 255) correlates with fibrotic EMT, while Smad2 (on residue 220) and Smad3 (on residue 179) linker phosphorylation correlate with the invasive behavior of fibrotic liver cells that progress to carcinoma development.