Emerging data underscore the regulatory role of various tumor microenvironmental stimuli in PDL1 expression [49,50], which is observed in several cancer types, including renal cell carcinoma, pancreatic cancer, ovarian cancer, gastric cancer, esophageal cancer, and breast cancer, while it remains absent in healthy epithelial tissues [51,52]. The gene discussed is CD274; the disease is familial pancreatic carcinoma.