Levels Of PD-1, PD-L1 And CTLA-4 In The Peripheral Blood Of Patients With Esophageal Squamous Cell Carcinoma And Its Clinical Implications

Objective: Esophageal cancer is a deadly disease,ranking sixth among all cancers in mortality.Although incremental advances in diagnostics and therapeutics,esophageal cancer is still poor prognosis.We can get new ideas for the treatment of esophageal cancer through the immune escape mechanism exploration.In recent years,the role of inhibitory costimulatory molecules in tumor immune response has drawn much attention,especially for the programmed cell death-1(PD-1),programmed cell death ligand-1(PD-L1)and cytotoxic T-lymphocyte-associated antigen 4 programmed death-1(CTLA-4).It has been reported that the expression of PD-1,PD-L1 and CTLA-4 in esophageal cancer tissue,but their expression in peripheral blood are rarely reported.So we check the the expression of PD-1,PD-L1 and CTLA-4 in the peripheral blood of patients with esophageal squamous cell carcinoma(ESCC)and discuss its clinical implications.We hope the result can provide a theoretical basis for the research and application of esophageal cancer immune targeting drugs.Methods: A total of 90 esophageal squamous cell carcinoma patients and 40 healthy people were enrolled in the study.Among the 90 patients,there were 50 patients underwent surgery.By using the coagulant vacutainer tubes to collect 5ml of blood(peripheral blood)and standing for 30 min,centrifuged at 3000*g,10 min,we got the supernatant.And then store them in-80? refrigerator.The expression levels of soluble PD-1(s PD-1),soluble PD-L1(sPD-L1)and soluble CTLA-4(s CTLA-4)in the serum were tested by enzyme-link immunology method.The data were tested and analyzed with SPSS 24.0 software.Results:1.The expression levels of s PD-1,s PD-L1 and sCTLA-4 in the esophageal squamous cell carcinoma group was significantly higher than that in the healthy people(P<0.05).2.The expression levels of sPD-L1 in preoperative patients was higher than that in postoperative patients(P<0.05),whereas difference was not observed between the expression levels of s PD-1(P>0.05).3.sPD-1 and sPD-L1 expression had no related to clinical significance,while s CTLA-4 expression was related to TNM stage(P<0.05),but not related to T stage,N stage,tumor size,tumor location,tumor cell differentiation,sex,age.4.The expression levels of s PD-1 and s CTLA-4 had no correlation.Conclusion:1.The expression levels of sPD-L1 was higher than that in healthy people and after surgery the sPD-L1 expression declined.It suggested that s PD-L1 may be associated with esophageal squamous cell carcinoma development.2.The expression levels of sCTLA-4 was higher than that in healthy people and the sCTLA-4 expression was related to TNM stage.It suggested that sCTLA-4 may be related with severity of esophageal squamous cell carcinoma.