Given that PXDN depletion using siRNA reduced FAK phosphorylation in HUVEC cells, it could be speculated that PXDN expression and/or activity, and FAK signalling may work together to play a role in the invasion of breast cancer cells, although the direct interplay between FAK inhibitors and PXDN expression and activity should be further explored in this setting. Here, PTK2 is linked to breast carcinoma.