Antibodies against pFAK Tyr576/577, pSrc Tyr419, pLyn Tyr397, or pFyn Tyr420 were used to immunoprecipitate the lysates from paired primary and metastatic ESCC cells or KYSE410 and KYSE510 cells from the primary site and lymph nodes, and the expression of pACLY Tyr542 and Tyr652 and pALDOA Tyr174, Tyr302, and Tyr328 in FAK/SFK complexes was evaluated by immunoblotting. This evidence concerns the gene PTK2 and esophageal squamous cell carcinoma.