EGFR and cancer: As shown in Figure 4A, PBSA treatment markedly inhibited mitogen‐induced expression of integrin β1, which plays important roles in cell adhesion, migration and invasion associated with cancer growth and progression.5, 25, 26 However, PBSA did not modulate the expression of receptor tyrosine kinases (RTKs) including VEGFR‐2, FGFR‐1 and EGFR, raising the possibility that anti‐cancer activity of PBSA might be mediated by the regulation of downstream signalling components of RTKs and integrins.