Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays a vital role in many oncogenic pathways. Defactinib is a dose-dependent inhibitor of FAK, with maximal inhibition of FAK autophosphorylation in cells achieved at 10 μM. It is less effective against the related kinase Pyk2. Defactinib restores the chemosensitivity of taxane-resistant cells to paclitaxel , although it is not cytotoxic alone. Defactinib decreases YB-1 phosphorylation and nuclear accumulation in an Akt-dependent manner. It is orally bioavailable, inhibiting FAK and augmenting paclitaxel action in suppressing the growth and number of ovarian cancer cell tumors in mice.
