The results showed that the levels of the activating receptors NKG2D and NKp30 (Fig. 3e and f) and the levels of the effector molecule granzyme B (Fig. 4a and b) were suppressed in the ESCC#1 and ESCC#2 co-cultured supernatants in comparison with those in the RPMI1640 medium (NC) supernatant of healthy oesophageal cell lines KYSE150 and EC9706. This evidence concerns the gene KLRK1 and esophageal squamous cell carcinoma.