SERPINE1 and cancer: FOSB regulates SERPINE1 directly, which is in line with our previous finding that truncated FOSB was able to regulate its own transcription,21 as well as via SMAD3. Both exhibit a self-regulatory mechanism, which could further activate many genes in the network of cellular growth and proliferation and cancer processes directly or indirectly through the activation of the TGF-β signaling pathway (Figure 3E).