Activation of ZEB1 or Snail leads to an increase in PDL1 expression (41); thirdly, in patients with cholangiocarcinoma, high expression of EMT markers, such as ZEB1, N-cadherin, and Vimentin, along with low expression of E-cadherin, are associated with increased PDL1 expression (42); lastly, similar results are observed in esophageal squamous cell carcinoma, patients with elevated levels of EMT marker ZEB1 and positive PDL1 have the worst prognosis (43). This evidence concerns the gene CD274 and esophageal squamous cell carcinoma.