PTK2 and cancer: Another study showed that expression of the T-cell co-stimulatory ligand CD80 on cancer cells sensitises tumours to FAK inhibition, and that in the absence of CD80, targeting alternative T-cell co-stimulatory receptors OX-40 and 4-1BB in combination with FAK, can drive enhanced anti-tumour immunity and even complete regression in syngeneic mouse models [41].