We examined whether FAK was activated in leukemia cells from patients and showed by Western blot analysis (Fig. 1a(i)) and confirmed by quantitative real-time polymerase chain reaction (PCR) analysis (Fig. 1a(ii)) that FAK protein expression is higher in leukemia cells from patients (n = 10) than in lymphocytes from normal volunteers (n = 3). This evidence concerns the gene PTK2 and leukemia.