Fig. 7a, b, ECM stiffening elevated mutp53 protein levels and resulted in a p53-dependent increase in the expression of SLC7A5 and PSAT1. Conversely, BC cells grown on plastic (a hyperstiff substrate) exhibited reduced mutp53 protein levels and decreased transcription of SLC7A5 and PSAT1 genes when treated with mechanosignaling inhibitors that target focal adhesion signaling (e.g., FAK inhibitor PF573228, Src family inhibitor Dasatinib)66,67 and actin polymerization (e.g., Cytochalasin D and Latrunculin A)68 (Suppl. This evidence concerns the gene PSAT1 and breast cancer.