TGFB1 and cancer: During cancer differentiation and metastasis processes, upregulation of integrins has been linked to cancer invasiveness.79, 80 Among others, the β1‐integrin subunit is expressed in metastatic cells and can be considered as indicator for metastasis.81 Xu et al82 observed that TGF‐β1 had obviously increased the expression of integrin α5β1.