IFN-γ played a role here as demonstrated in the study by Rowe and Payne, inducing the expression of PD-L1 on non-resting Ki67 +/Ki67-low cells, and the high expression of PD-L1 attenuated T-cell activation, constituting a factor of immunosuppression in ESCC tissues[23–25]. This evidence concerns the gene MKI67 and esophageal squamous cell carcinoma.