Currently, PD-L1 positive expression as a biomarker for pembrolizumab 3rd-line treatment regimen in GC has been approved by the FDA [27], and nivolumab has been approved in many regions as a treatment regimen for unresectable late or recurrent GC, regardless of PD-L1 expression, which indicates that the potential and application range of immunotherapy are expanding. Here, CD274 is linked to gastric cancer.