SERPINE1 and neoplasm: Further characterization of TGF‐β1/Smads signalling was performed by evaluating Smad2 and Smad3 phosphorylation, as well as the mRNA expression of tumour‐promoting TGF‐β1 target genes such as plasminogen activator inhibitor (PAI1),37, 66 ZEB66 and the high‐mobility group A2 (HMGA2),67, 68 in the same experimental conditions described above, in both DU145 and PC3 cells (Figure S3).