TWF1 and prostate cancer: Among the several integrins, α2β1 integrin, which is a receptor for collagen, is abundantly expressed in prostate cancer cells [11], and the invasiveness of PC3 cells could be attenuated by administration of α2 and β1 neutralizing antibodies, but not α1 and α6 neutralizing antibodies [12], indicating that prostate cancer cells may primarily use α2β1 integrin during migration and adhesion.