SERPINE1 and neoplasm: Therefore, although uPA, PAI1, and PAI2 are TGFβ-responsive genes and final changes in the uPA activity and other EMT-like features in H4 cells correlated only with ATRA treatment, H4 cells did not exhibit all of the EMT-like features but it could be ascribed to partial EMT or similar process found in both physiological processes and in tumour biology [29,36].