To determine whether Psmb8 upregulation contributed to the growth defect of FAK-/- tumours, 0.5×106 FAK-wt, FAK-/-, FAK-/-Psmb8-/-C23 or FAK-/-Psmb8-/-C34 cells were implanted into the pancreas of C57BL/6 mice and tumours harvested and weighed after 2 weeks. This evidence concerns the gene PTK2 and neoplasm.